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PROJECTENGINEERINGPreliminary Design Report
Substation Name: Sirius Substation Job ID: IPP147160851‐00001 Job Name: Sirius 132kV Substation Author: Trans‐Africa Projects Date: July 2015 Revision: 0
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INDEX:
SECTION A: GENERAL 4
SECTION B: POWER PLANT CONCEPTUAL DESIGN 14
SECTION C: CONTROL PLANT CONCEPTUAL DESIGN 27
SECTION D: CRA FORM 45
SECTION E: PROJECT SCHEDULE 49
SECTION F: KEY ROLE PLAYERS 51
SECTION G: BOM: PRIMARY PLANT 53
SECTION H: BOM: SECONDARY PLANT 64
SECTION I: BOQ 77
SECTION J: COST SUMMARY 80
SECTION K: PRIMARY PLANT DRAWINGS 83
SECTION L: SECONDARY PLANT DRAWINGS 91
SECTION M: ARCHITECTURAL LAYOUT 98
SECTION N: EARTHGRID DESIGN REPORT 100
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SECTION A: General
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UCONTENTS
1 EXECUTIVE SUMMARY 6
2 PROJECT SPECIFIC REQUIREMENTS 7
3 EXISTING NETWORK DIAGRAM 8
4 PROPOSED NETWORK DIAGRAM 9
5 SUBSTATION LOADING 10
6 GENERATION TECHNOLOGY 10
7 FAULT LEVELS 10
8 PROJECT MILESTONES 10
9 OPTIONS CONSIDERED 10
10 SCOPE OF WORK 11
11 ASSOCIATED PROJECTS 13
12 QUALITY OF SUPPLY IMPLICATIONS 13
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1 EXECUTIVE SUMMARY
Scatec Solar has been awarded 3 x 75MW solar PV projects, which are all located a short distance outside the town of Upington in the Northern Cape. The solar PV sites are called Dyasonsklip 1, Dyasonsklip 2 and Sirius 1. A substation will be constructed on the Sirius 1 site (called Sirius substation) and a separate substation will be constructed on the Dyasonsklip 1 site (Dyasonsklip substation). Sirius substation will act as a collector station for the power generated from the new Sirius 1 PV facility. The 132kV line from Dyasonsklip substation will also connect on the Sirius 132kV busbar. The outgoing 132kV line from Sirius substation to the new MTS will carry the power of all 3 x 75MW PV facilities.
There is an existing 132kV network in the region, but there is limited capacity for new connections and the nearest existing potential connection points are located some distance away from these sites. To facilitate the connection from these 3 x 75MW solar PV sites (and other future IPP projects planned for this region), Eskom will be constructing a new Main Transmission Substation just outside Upington.
This report addresses the proposed design of the Eskom side of the Sirius 132/33kV substation.
The Eskom side of the Sirius substation will consist of two fully equipped 132kV line feeder bays and one fully equipped 132kV transformer feeder bay. There will be a single 132kV tubular busbar, but no 132kV bus‐section at this stage. The layout will allow for the addition of future feeder bays and space will be allowed for a bus‐section
Figure 1 shows the substation location and the surrounding area.
Upington Town
Sirius SS location
Solar Park MTS (proposed)
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Figure 1: Geographical Location
2 PROJECT SPECIFIC REQUIREMENTS
There will be no available 3 phase AC supply on site during the construction phase, as this is a new substation and there is no existing AC supply. It will be the responsibility of the contractor to provide a suitable 3 phase generator that is adequately sized for all the load requirements during construction. Further to this the contractor will be responsible for maintaining and refuelling the generator throughout the construction phase. The generator will be required from the start of construction right up to the point when the substation is commissioned and the permanent auxiliary supply becomes available.
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3 EXISTING NETWORK DIAGRAM
Figure 2: Existing Network Diagram
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4 PROPOSED NETWORK DIAGRAM
Figure 3: Proposed Network Diagram
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5 SUBSTATION LOADING
Once constructed and commissioned the initial loading on the substation will be from the Sirius 1 75MW PV facility and from the 2 x 75MW Dyasonsklip PV facilities. The 132kV line from Sirius substation to the new MTS will have the capacity to carry the power from 5 x 75MW plants. The substation has place for an additional 2 line feeder bays.
As this is a new substation there is no historical substation load data available.
6 GENERATION TECHNOLOGY
The Sirius facility will generate electricity using Photovoltaic (PV) solar panels. PV panels effectively convert sunlight into DC electricity. To generate usable amounts of electricity several PV cells are connected together to create solar cells. The DC electricity produced is then converted to AC through the use of inverters and the power is then stepped up further from there.
The output power from the inverters at Sirius 1 and Sirius 2 PV facilities is at 400V AC. This power is then stepped up to 33kV via pad mounted transformers, which are located adjacent to each inverter station. At the substation the voltage is further stepped up from 33kV to 132kV before being distributed onto the Eskom Grid.
7 FAULT LEVELS
Table 1: Fault Levels
Busbars 1 Phase Fault (kA) 3 Phase Fault (kA) 132kV busbar at Solar Park MTS 39.9 32.5 132kV busbar at Sirius substation 21.6 24.2 Table 1 summarises the expected future fault levels. The given fault levels allow for standard equipment to be used.
8 PROJECT MILESTONES
Milestone Date TEF date July 2015
Financial Close November 2015
Detailed Design Phase (Eskom) December 2015 (Est.)
Energise substation (Eskom ready to energise) March 2018
Commercial Operation Date April 2018
The dates provided here assume that the necessary infrastructure at Solar Park MTS will be completely constructed and commissioned by December 2017/January 2018. These dates are approximate and may change.
9 OPTIONS CONSIDERED
The scope of the project is limited to 2 132kV line feeder bays and a single transformer bay. Space will be provided for 2 additional line feeder bays and 1 additional transformer bay in future.
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The only option considered was a single tubular busbar, as this limits the substation footprint as well as the overall cost of construction. The tubular busbar provides sufficient capacity for the current and potential future needs of the network in this region.
Option 1: ‐ A fully equipped transformer feeder bay with busbar side and IPP side isolators, circuit breaker
and CTs ‐ Fully equipped 132kV line feeder bays with busbar isolators, motorised line isolator (on the MTS
line feeder bay only), surge arrestors, circuit breaker, CTs and power VTs (for auxiliary power supply)
‐ 132kV tubular busbar with busbar VTs. Space will be allowed for the installation of bus‐section isolators in future
10 SCOPE OF WORK
Power plant
Install the following new HV equipment with foundations in the following bays as per Table 2:
Table 2: New Major Equipment
Install the following new equipment:
Earthgrid and connect the new equipment to the new earthgrid
120x4mm tubular aluminium busbar for 132kV busbar
Single Centipede conductor for all HV equipment jumpers in the transformer bay
Double Bull conductor for all HV equipment jumpers in the line feeder bays
Centipede conductor for the 132kV VT jumpers in the busbar bay
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6m medium equipment supports for the line and earth wire terminations
Lighting/lightning masts
Yard stoning, to be the standard 100mm thick
Clamps
Architectural
Construct a new Eskom control building with a toilet and store room.
Install an external water tank on the Eskom control building
Install a conservancy tank
Civil
Construct new access and internal roads.
Construct a new terrace with cut and fall with suitable drainage.
Control Plant
Install the following control plant equipment :
1 x Feeder scheme (4FZD3920) for the Solar Park 1 Feeder bay
1 x Feeder scheme (4FZD3920) for the Dyasonsklip 1 Feeder bay
1 x Motorised Isolator Control Module ( 4BC1900 ) for the Line Isolator
1 x Protection scheme (4RF1101 with High Z Diff – RMS 2V73 ) for the PV 1 & 2 Feeder bays
1 x HV Buszone protection scheme ( 4BZ5900 )
1 x AC panel for AC and DC Distribution Modules
1 x DC panel for the 20A Charger and Interface Module
1 x 110V DC, 100Ah NiCad battery bank
1 x Tariff metering panel fitted with QOS meters
1 x Stats metering panel
1 x Substation Automation & Tele-comms panel
1 x Security Systems panel
1 x D20 RTU and 40 way IDF
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3 x CTJB’s, 1 x VTJB & 1 x Power VT JB
1 x Interface JB & 1 x Yard AC Distribution Board
37B General
Install new:
Labelling and signage to standard
Steel mesh palisade perimeter fence with kerbing and stone
Diamond mesh HV yard fences
11 ASSOCIATED PROJECTS
IPP147160851-00003 – Dyasonsklip 132kV Substation IPP147160851-00002 – Solar Park MTS – Sirius 132kV line IPP147160851-00004 – Sirius - Sirius 132kV line IPP147160851-00005 – Solar Park MTS 1 x 132kV feeder bay for Scatec 3 x 75MW PV
(not done by TAP)
12 QUALITY OF SUPPLY IMPLICATIONS
A high level construction sequence for the Sirius substation is provided below.
Clear the site area of any vegetation and/or obstacles Construct the access road leading to the substation Construct the substation platform including drainage system Construct the internal substation road Construct the Eskom control building Install equipment foundations Erect steelwork and mount the HV equipment Jumper conductors between equipment in the bays Install control panels and cabling Energise and commission each bay in the Eskom side of the substation
No customers will be impacted during the construction of the substation, as this is a new substation.
There will be a separate constructability plan for the establishment of the Solar Park MTS and the 132kV feeder bay for the 3 x 75MW Scatec projects. This will form part of project IPP147160851‐00005.
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SECTION B: Power Plant Conceptual Design
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CONTENTS
1 DIAGRAMS 16
2 SITE CONDITIONS 16
3 GEOTECHNICAL INFO: 16
4 ENVIRONMENTAL INFO: 17
5 SUBSTATION YARD AND ASSOCIATED EQUIPMENT 17
6 MATERIAL FOR RECOVERY & SCRAPPING 24
7 FIRE PROTECTION SYSTEM 24
8 SECURITY 24
9 LABELLING 25
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1 DIAGRAMS
Station Electric Diagram – See SECTION K:
Conceptual Layout Drawings – See SECTION K:
Conceptual Earthgrid Drawing ‐ See SECTION K:
2 SITE CONDITIONS
Site location:
Sirius substation site is located approximately 3km west from the new Solar MTS and approximately 23km south‐west of Upington town in the Northern Cape. The site co‐ordinates are 28°33'6.48"S, 21° 6'20.07"E.
Site detail:
Site is a virgin piece of ground.
Existing substation access:
New solar PV facility roads will be constructed for the offloading of the equipment inside the PV
facility. The substation position will be adjacent to one of the internal roads. It will be necessary
to create a short access road from the internal road to the substation.
Existing infrastructure to be located:
None
3 GEOTECHNICAL INFO:
Drainage:
The drainage will be contained in the new site platform with a minimum fall of 1:100.
Soil resistivity:
Please refer to the separate preliminary earthgrid design report (see SECTION N) for further details on the soil resistivity for this substation.
Soil type:
In geological terms the area lies in the Gordonia Sub‐province forming part of the Namaqua Metamorphic Province and is underlain by metamorphic as well as intrusive (granite/gneiss) rocks. Soil on the site are thin (generally< 500 mm) red sands often containing calrete gravel, while denser honeycombed calcrete often occur near the upper bedrock surface. This bedrock is coarse grained gneiss of intrusive origin and contains mainly quartz, feldspar, biotite and garnet.
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The bedrock is partially covered by younger calcareous rock (calcrete) and sandy soil of limited thickness.
4 ENVIRONMENTAL INFO:
Coastal:
No
Snow/Ice:
No
Atmospheric conditions:
The hottest month of the year is January, with average daily temperatures swinging from 36 °C
to 20 °C, while in the coolest month of July temperatures range between 21 °C and 4 °C. Also the
dryest month of the year, July sees an average rainfall of only 2 millimetres, while the wettest
month of March sees 37 millimetres. Upington has been noted as being the sunniest location on
the planet for three months of the year, from November through January.
Environmental Sensitivity of the Area:
No. Refer to the environmental management plan for more detail.
5 SUBSTATION YARD AND ASSOCIATED EQUIPMENT
5.1 Earthing
The substation new earthing system will consists of buried interconnecting horizontal earthing grids,
connecting flat copper conductor from the buried earthing grid to metallic parts of structures and
equipment, connections to grounded system neutrals, and the ground surface insulating covering
material. New horizontal earthing will be installed 1000mm to 2000mm outside the perimeter security
fence where possible. The new earth grids and tails will be welded together where they cross. All joints
shall be oxy‐acetylene brazed using 3mm diameter silbralloy brazing rods (no flux is required). Note that
crimping shall not be used.
All the earthing in and around the substation must adhere to the Eskom standard D‐DT‐5240 (using the
latest revision).
5.1.1 Main earth grid:
A new main earth grid will be installed with 10mm diameter round annealed copper buried at least
500mm below finished ground level.
Where passing under deeper foundations and drains, it must be 150mm below the concrete. Back‐filling
around the earth conductors and rods is to be well compacted. Where a concrete blinding is cast under
building foundations, the earth grid meshes are to be installed on top of the blinding and under the
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concrete footing of columns etc. Where passing over drains with less than 1000mm of cover, they are to
be buried as deep as possible. The outer grid is to be a minimum of 1000mm outside the safety fence.
5.1.2 Corrosion protection:
Four new sacrificial anodes (a steel railway tract, see drawing in the Eskom standard D‐DT‐5240) will be
installed and connected to the substation main earth grid.
Eliminate any source of stray currents if possible (see SCSASABF9, Earthing of Sub‐transmission line
structures for shield wire connection strategies). If it is not possible to eliminate stray currents (e.g. the
substation is close to a DC railway system), extra sacrificial anodes needs to be installed even if the soil
is not highly corrosive.
5.1.3 Foundation reinforcing:
Connection of the reinforcement bars in the foundations to the earth grid shall be according to D‐DT‐
5240 sheet 10 and the relevant foundation details. The connections shall be done with a line tap clamp,
as per D‐DT‐3048. It is important to note that reinforcing mesh is to be bonded on one side only to the
main earth grid.
5.1.4 Bolted Connections:
All bolted down surfaces must be cleaned (wire brushed) and filled with a suitable joint compound (non‐
oxide grease) to prevent oxidation of the joint. No paint barrier is allowed. Any paint films which might
otherwise introduce a highly resistive joint should be removed. Any scraped area around the joint shall
be made good by using the original types and colours of paint.
5.1.5 Steelwork and main equipment:
All the equipment must be earthed in two places using a single 50 x 3mm flat copper earth strap
connected to the main earth grid.
5.1.6 Fencing and gates:
All fences must be earthed at an interval less than or equal to 20m. Reference must be made to the
earth grid layout for the details of all the points to which the fence is to be connected to the main earth
grid. The 50 x 3mm copper leads shall be bolted to the steel fence posts at the lug points provided, with
the instruction that these connections must not be visible above the final layer of yard stone.
Each gate leaf of all gates, installed in the security fence, shall be electrically coupled to the adjacent
gate post, via a 70mm2, UV stabilized, sheathed, stranded flexible copper conductor that is suitably
lugged and bolted at each end.
It is important to ensure that when opening the substation gates the operator is not at risk from mesh
potentials. To overcome this problem the following is to be done:
One meter personnel gate. The yard stone and curbing is to extend 1.5 meters outside the gate
entrance and one meter to the side of each gate post.
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Five meter double leaf gate. A concrete slab reinforced with reinforcing mesh top and bottom
shall extend 3.5 meters from the fence and 1 meter to the side of each gate post. It is important
to note that mesh is to be bonded on one side only to the main earth grid.
Five meter sliding gate. A concrete slab reinforced with reinforcing mesh top and bottom shall
extend 1 meter from the fence and 1 meter to the side of each gate post. It is important to note
that mesh is to be bonded on one side only to the main earth grid.
5.1.7 Ancillary equipment:
All ancillary equipment (CT and VT junctions boxes, etc.), shall be connected to the main earth grid via
50mm x 3mm flat strap between the earth stud of the equipment and the equipment steelwork. For the
earthing detail refer to the drawing set D‐DT‐5240 using the latest revision. Any foundation that does
not allow for earthing inside the foundation must be earthed in accordance with D‐DT‐5240 sheet 3
(using the latest revision).
5.1.8 Control building:
A new control building will be constructed to the Eskom standard. All reinforcing used in the floors of
the relay room and switch room in the substation building, shall be bonded to earth grid in accordance
with the standard.
Each new floor standing panel shall be bonded to the overhead rack, by means of a 16mm2,
green/yellow, insulated, stranded flexible copper conductor. These tails shall have one end securely
lugged and bolted to the 50 x 3mm earth bar and the other end securely lugged and bolted to the panel
earth bar, via an M12 brass set screw. The overhead rack must be continuously bonded and connect to
the earth grid and will then serve as the “earth bar” for the panels.
5.1.9 Yard stone and concrete kerbs:
100mm thickness of minimum 26mm grade granite, tillite or dolerite stone chips, depending on the
availability of the above stone types in the area concerned, shall be placed in the substation yard.
The stone chips must be derived from the crushing of solid, un‐weathered quarried rock. The material
must be free of dust and other deleterious substances. The material must comply with the specification
SANS 1200M : 1996 (Roads – General) – Table 1 – Single‐sized crushed aggregates. A 1200 mm to
2400mm border must extend beyond the perimeter with kerbing and yard stone to reduce electrical
touch potentials.
5.2 Fencing
A new medium risk fence will be installed around the perimeter of the site and a low risk fence around
the HV yard.
5.2.1 External security fence:
Category: medium risk fencing as per DISASADJ6.
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The fence will be installed with steel palisade in accordance with D‐DT‐5237 (using the latest revision). A
motorised palisade sliding gate will be installed at the main entrance in accordance with D‐DT‐5237.
Signage placed on the fence needs to be in accordance with D‐DT‐5237. For information on the intruder
alarm system, CCTV, armed reaction units and more see point 8.
Kerbing (300 mm x 75 mm x 1 000 mm) shall be set in concrete underneath the security fence to
prevent excavation under the fence in order to gain unauthorized access. The kerbing shall be set in
concrete immediately underneath the fence.
5.2.2 Substation internal fence (Low risk):
Category: low risk fencing as per DISASADJ6.
The fence will be installed with the standard 1.8m diamond mesh fence in accordance with D‐DT‐5237
(using the latest revision). This fence will only be used to demarcate the HV yard.
No kerbing is needed underneath the security fence to prevent excavation under the fence.
5.3 Foundations
All civil engineering construction must be to reference of SANS 1200 (Standardized specification for civil
engineering construction Section A – DM) and in accordance with Eskom Specifications. These aspects
include all the following: excavations, placement of reinforcing steel and embedded items, formwork,
backfilling, mixing and placement of concrete, construction joints, concrete curing and workmanship.
5.3.1 Excavations:
The following requirements shall apply to foundation excavations:
foundation excavations shall be dug as close as possible to the required size;
where the depth of the foundation excavation is deeper than 1,5 m, shoring shall be used;
shoring shall be used where the soil has a tendency to cave in: for example, in sandy soils or soft
cays;
the bottom of all foundation excavations shall be level and cut squarely with the sides of the
excavation; and
if there is loose soil, sand or mud in the bottom of the foundation excavation, it shall be
removed prior to concrete placement. The soil shall be moistened and compacted with a
mechanical plate compactor to ensure the bottom is firm and settlement is avoided.
Where muddy, loose or uneven material makes it difficult to get even and flat excavation
bottom surfaces a blinding layer of 10 MPa concrete, 50mm thick must be installed to ensure
even concrete cover to the reinforcing.
5.3.2 Reinforcing:
The required steel reinforcing for a foundation may only be placed after the correct excavation is done.
In order to protect the steel reinforcing against possible corrosion, the steel should be covered by a
concrete layer with a minimum thickness of 50 mm after the pouring of the concrete. As the bottom of
the foundation excavation is probably not smooth, the cover thickness at the bottom is increased to 75
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mm. This is done by placing the bottom steel on concrete spacer blocks of 75 mm and 50 mm spacer
blocks on the top steel.
Before casting the concrete the engineer should check whether the steel placed in each foundation is
correct according to the foundation design and if correct sign it off on the as constructed record. The
slump of the concrete mix must also be correct.
5.3.3 Concrete:
All applicable foundations shall be of a uniform strength of 25MPa at 28 days throughout unless
otherwise specified, and constructed in strict accordance with the relevant drawings and specifications,
The foundation tolerances must be in accordance with SANS 1200 G.6 Grade II.
Once the casting of a particular foundation is completed, all exposed surfaces should be sprayed with a
curing compound or covered with plastic (or wet sand) to ensure optimal curing of the concrete. Before
this is done the Engineer should check that the concrete is right up to the top of the top cover blocks or
the required cover is achieved.
5.3.4 Backfilling and compaction:
Backfilling and compaction of foundation excavations can only start after 3‐days providing that the 7 and
28 day crushing strengths of the concrete meets the specification requirements later on. To ensure that
the excavated material is optimally compacted the material should be moistened to Optimum Moisture
Content (OMC) and placed in layers of less than 300 mm thick and compacted with a mechanical plate
compactor. No particles (i.e. rocks) may be larger than 150 mm (or 2/3 of the compacted layer
thickness) to ensure proper compaction of the layers.
Where the excavated material is considered to be unsuitable for backfill, such as a material with high
clay content or a sandy material with little variation in particle size, the Contractor shall propose a
suitable method of soil improvement for consideration and acceptance by the Engineer prior to being
implemented. This material shall be properly mixed, moistened, placed and compacted in the same
manner as excavated material.
5.3.5 Holding down bolts:
All holding down bolts steelwork galvanizing shall be done in accordance to SANS ISO 1461. Only steel
templates may be used for setting out the holding down bolts. The holding down bolts must be aligned
to a tolerance of ±2mm. All the holding down bolts must be fitted with 2 nuts and 2 washers. All the
bolts, nuts and washers needs to be in accordance with SANS 1700. Refer to the specific foundation
drawing.
5.4 Oil drainage and fire protection
5.4.1 Oil drainage:
The layout and position of the oil dam and drainage layout are not part of this design. These aspects of
the design will be covered under the design of the IPP side of the Sirius substation.
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5.4.2 Fire protection:
Not applicable in this project.
5.5 Steelwork
All the equipment supports and substation steelwork must be galvanized to SANS ISO 1461 specification
and delivered to site as complete bundle sections, in accordance with the appropriate drawings
established for the relevant item.
All the structures shall be erected, aligned, squared, plumbed and levelled in accordance with SANS
1200 H 6.2.2.c) 2 – CLASS II. All the bolted connections shall be cleaned and filled with jointing
compound. No paint barrier will be allowed.
5.6 Electrical Equipment
All the primary plant equipment will have a minimum of 31mm/kV creepage.
An earth switch will be installed on the incoming line side of the isolator facing the MTS substation side.
Portable earths are being used as per SCSASABK3 Distribution Standard, Part 7: Substations, Section 2:
Generic Substation Design.
5.7 Clamps and Conductor
Equipment not fitted with 26mm or 38mm connection prongs must be fitted with tinned 26mm or
38mm brass prongs drilled and tapped to the appropriate sizes.
All surface areas of conductor or contact area of connection clamps must be treated as described in
drawing mentioned below prior to making a clamped or crimped connection.
The conductors types used in this project are the following:
twin bull conductor,
single centipede conductor,
120 x 4mm aluminium tubes,
Tube vibration damping for high wind conditions must be done for any 120mm diameter aluminium
alloy tube exceeding 5.5 metre in length. This is done by installing two single centipede conductors 2/3
of the length of the tube, fixing it at both ends. A drain hole of 10mm diameter should be drilled at the
bottom centre point of aluminium alloy tubes to facilitate drainage of condensate moisture.
Refer to the bay elevation detail drawings for the clamp and conductor details.
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5.8 Cabling and Termination
5.8.1 Cable trenching:
All the LV cables (≤ 1000V) shall be laid in the new cable trench.
All the trenching work shall be done in accordance with SANS 1200 DB: 1989 (using the latest revision).
Refer to the drawing set 0.54/390 sheet 15 for the LV protection multi‐core cable trenching details,
0.54/390 sheet 17A for the trench cover details, and SANS 927‐1969 figure 5 for the trenching wall
details. No special back‐fill material is required to close the trenches once all cables have been installed,
but any boulders, sharp objects, construction debris or other such objects likely to cause damage to the
cables, shall be removed from the trench and backfill material, before the trenches are closed. Danger
tape shall be laid in all cable trenches approximately 300mm below final ground level. Trenches from
the equipment to the cable trenches shall be hand excavated and backfilled once cables have been laid.
Backfilling shall be done by using the excavated sand.
The water from the trenches will be drained from the substation yard. For drainage details refer to the
storm water drainage drawing in civil section.
5.8.2 LV cable termination:
All the low voltage armoured cables shall be terminated by means of mechanical glands, fitted with
earth rings and shrouds. These cables shall be identified at both ends by punched or engraved brass tags
attached to the cable with galvanized wire. The cores shall be correctly identified with alphanumeric
ferrules and terminated with the correct size of hook blade connectors, as indicated on the relevant
electrical drawings.
5.8.3 MV Cable trenching and termination:
Not applicable in this project.
5.9 Lightning protection
The substation will be protected by five 21 metre lightning spikes that together will form a combine
protect zone for the equipment in the yard against direct lightning strikes. Refer to the site plan drawing
in section K for the placement details of the lightning masts.
5.10 Substation illumination
Combined operational and security lighting shall be provided by multiple 400 Watt high pressure sodium
(HPS) floodlights strategically placed within the substation yard and mounted on the lightning masts as
indicated on the reference drawing. The lighting system shall also provide a floodlighting effect, giving
an average illumination of 10 lux at yard stone level, with a maximum diversity factor of 5 throughout
the area.
The beam spread shall be H5V2 [71‐1000 horizontal, 19‐290 vertical] according to SANS 1279 – 1980.
The Lamp requirement shall conform to a 400 W clear tubular high pressure sodium lamp for normal
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operation and a 400 W clear tubular twin arc standby high pressure sodium lamp for when operational
floodlighting installation is controlled remotely by the security fence monitoring equipment. The
luminaire shall have an ingress protection rating of IP55 according to SANS 1222‐1985.
The light circuit(s) shall be protected by a suitably rated LV MCB and associated contactor, located in the
AC distribution board in the yard. The operation of the lights provide the combined operational /
security functionality, and shall be controlled by a "three stage switch". The switch can be selected to
operate either via a “Daylight” photocell installed on an external wall of the substation control building
or dry N/O output contact from the security alarm system for alarm operation during night time only or
manually operated. Each floodlight shall be isolated locally via a suitably rated LV single‐pole MCB
mounted in a box at the base of the relevant mast.
Please note: A compliance certificate must be issued by the contractor responsible for the LV installation
in the substation yard; to ensure that all the installations complies with the requirements of SANS 10142
in every applicable respect.
6 MATERIAL FOR RECOVERY & SCRAPPING
Not applicable in this project.
7 FIRE PROTECTION SYSTEM
Fire extinguishers: ‐ New.
Transformer fire walls: ‐ Not applicable in this project.
Oil retaining tank: ‐ New, but not part of the design of the Eskom side of the substation.
8 SECURITY
A new steel palisade fence (as per DISASADJ6) will be installed around the perimeter of the substation
site. Eskom requires that the main 5m vehicle access gate that provides access to the Eskom control
building yard is motorised. In addition there must be a 1m pedestrian gate in the perimeter fence
adjacent to the main gate to allow access in the event of failure of the gate motor.
An intruder alarm system will be installed, together with access control. The system shall be installed by
Eskom’s preferred security contractor and must adhere to the relevant Eskom specification 240‐
91190304.
The Eskom Substation security must comply with the following requirements:
An alarm monitoring system will be installed including video recording on site and
communications to a security control centre monitored by an Eskom approved contractor
Passive Sensors and a Dome camera mounted inside the relay house
A centrally located Pan Tilt Zoom (PTZ) camera mounted on the relay house
A fixed camera mounted on the relay house facing the gate
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Four fixed cameras on the perimeter of the Eskom side of the substation positioned to create a
‘virtual fence’
A cabinet for housing the equipment in the Eskom control room
There will be a DVR on site in order to record any incident on site. The DVR will be set up to
record when the alarm is triggered.
The electric gate will be controlled by the alarm system
The security system will be 110V DC and will be powered from the 110V batteries
All security equipment must undergo Factory Acceptance Testing (FAT), as specified in the
Eskom specification 240‐91190304
The Substation lighting will also be turned on when the alarm is triggered
The cameras in the yard will need to be mounted on either 5.7m spun concrete poles (as per D‐DT‐0010)
or 4.5m steel reinforced poles (as per D‐DT‐0011), according to Eskom specifications.
The alarm system will be housed in a ‘fibre panel’ which will be supplied and installed by the term
contractors. Space must be allocated in the relay room for the security panel. A 110VDC MCB must be
allocated for the power supply of the security panel.
The security cable will share the control cable trenches where possible. Security cable will be laid in
50mm Kabelflex conduit when in cable trenches and in security trenches. The security cables will enter
the relay house in the same way as control cables.
9 LABELLING
All the HV equipment will be labelled with new fibre glass equipment labels in accordance with the
following standards and specifications:
SCSSCAAP5 – Manufacturing specification for distribution equipment labels.
DISASAAN0 – Standard for the labelling of high voltage equipment.
Refer to the proposed station electric diagram for H.V. equipment label details and electrical phasing.
A substation name label, made from Chromadek as per D‐DT‐5047 sheet 1, shall be installed on the 5 m
perimeter access gate.
All new substation building and indoor labels shall be manufactured and installed according to
DISSCAAK9, Specification for labels on control panels, relay panels and other indoor and outdoor
equipment and D‐DT‐5049.
The substation label schedule can be seen in the following summary of the label schedule:
Sign A, B, C, Unauthorised Entry Prohibited D‐DT‐5015 sheet 1 – every 20 m along fence
Sign D, E, and Procedure in Case of Fire D‐DT‐5016 sheet 1 – every fence gate
Phase Disk – Red Plate Chromadek D‐DT‐5064 sheet 4
Phase Disk – Blue Plate Chromadek D‐DT‐5064 sheet 4
Phase Disk – White Plate Chromadek D‐DT‐5064 sheet 4
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Substation Name Labels D‐DT‐5047 Type Large
Substation Equipment Labels D‐DT‐5047 – Type 2
Substation Equipment Labels D‐DT‐5047 – Type 3
Phase Disk Mounting Bracket D‐DT‐5047 & D‐DT‐5273
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SECTION C: Control Plant Conceptual Design
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CONTENTS
13 INTRODUCTION 29
14 SUMMARY 29
15 PROTECTION 30
16 METERING 32
17 AUXILIARY SUPPLY 33
18 SUPERVISORY AND TELECOMMS 35
19 SECURITY SYSTEMS 36
20 PANEL FOOTPRINTS 36
21 DRAWINGS 37
22 SUBSTATION AUTOMATION 37
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13 INTRODUCTION
Sirius substation is required to integrate the IPP into the Eskom grid at Solar Park MTS. All the control plant equipment shall be housed in a new control building for the 132kV equipment in the substation. New trenches shall be installed and routed into the building via external cable ladders onto an overhead rack in the control room. New control plant shall be installed for the 132kV Feeder bays and space shall be allocated for 2 future outgoing line bays.
This report addresses the control plant requirements i.e. Protection, Tele‐control, Metering and DC equipment for the project.
14 SUMMARY
The following control plant equipment shall be installed under this project:
1 x Feeder scheme (4FZD3920) for the Solar Park 1 Feeder bay
1 x Feeder scheme (4FZD3920) for the Dyasonsklip 1 Feeder bay
1 x Motorised Isolator Control Module ( 4BC1900 ) for the Line Isolator
1 x Protection scheme (4RF1101 with High Z Diff – RMS 2V73 ) for the PV 1 & 2 Feeder bays
1 x HV Buszone protection scheme ( 4BZ5900 )
1 x AC panel for AC and DC Distribution Modules
1 x DC panel for the 20A Charger and Interface Module
1 x 110V DC, 100Ah NiCad battery bank
1 x Tariff metering panel fitted with QOS meters
1 x Stats metering panel
1 x Substation Automation & Tele-comms panel
1 x Security Systems panel
1 x D20 RTU and 40 way IDF
3 x CTJB’s, 1 x VTJB & 1 x Power VT JB
1 x Interface JB & 1 x Yard AC Distribution Board
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15 PROTECTION
15.1 Feeder Protection
15.1.1 Solar Park 1 132kV Feeder 1 & Dyasonsklip 132kV Feeder 5:
The 132kV feeder shall be protected by a Current Differential protection scheme (4FZD3920). Sirius substation is approximately 3km away from the Solar Park MTS and shall make use of fibre as the comms medium for protection. Dyasonsklip is approximately 6km away and shall also use Current Differential protection (4FZD3920) on that bay.
Current Diff and Back‐Up OC & EF protection shall be applied to Core 1 and 4 of the CT respectively in these feeder bays.
Both schemes shall provide the following functions:
RED670 IED – Protection functionalities include: Main protection (Current Differential/
Impedance protection) with Fibre REA communications.
REF615 IED – Protection functionalities include: Directional Back‐up protection relay with
O/C, E/F, BF and ARC operation.
Additional Supervisory Binary Output Card for wiring to the IDF.
IEC61850 Remote Engineering Access via Ethernet and local testing.
IEC61850 Remote Engineering Access Ethernet switch.
Digital measurements via serial communication to the Master Station.
Junction Boxes:
1 x CT JB shall be installed for the protection and metering circuits required for each feeder
bay.
1 x VT JB shall be installed for the 132kV Busbar VT’s
1 x Power VT JB shall be built for the Power VT JB using a VRW20 junction box fitted with 3 x
20A MCBs for the Solar Park 1 bay.
New control cables shall be installed from the panel to the respective equipment in the yard
(Breakers, Isolators, Earth Switches and CTJB).
The scheme conforms to DSP 34-1288: Specification for a Distribution Feeder Distance /Differential Protection Schemes.
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15.1.2 PV 1 132kV Feeder 2 Protection:
This Feeder shall have the 4RF1101 protection scheme installed .The 4RF1101 scheme shall be installed together with the High Impedance Diff Relay – RMS 2V73.
The scheme shall provide the following functions:
Overcurrent and Earth Fault protection shall be applied to Core 1 of the CT in this bay. This shall operate the Feeder 2 breaker. The 4RF1101 scheme shall be ordered with the following :
MiCOM P145 IED – the protection functionalities include: Non‐Directional/Directional O/C,
E/F, SEF, ARC, BF and Under‐Frequency
Rear RS485 communication port supporting DNP3 for Serial SCADA
2nd Rear communication port for Micom P145 relay for Remote Engineering Access
High Impedance Diff shall be applied across the 2 x 132kV CT’s (CT Core 2 of the Feeder and TRFR 1 bay ). This shall operate the Feeder Breaker and TRFR Breaker for each respective bay via the 4RF1101 scheme.
The requirements shall conform to 240-61268576: Standard for the Interconnection of Embedded Generation.
Junction Boxes:
1 x CT JB shall be installed for the protection and metering circuits required for the feeder
bay.
1 x Interface JB shall be installed for any breaker and isolator status indications, CT wiring,
busbar voltage supplies and protection tripping circuits required by Eskom from the IPP and
vice versa.
15.1.3 Solar Park 1 132kV Motorised Line Isolator:
This 1 Line Isolator shall be motorised and controlled by a 4BC1900 Isolator control module installed below the 4FZD3920 scheme on the Feeder 1 panel. This allows Control to remotely operate and isolate the bay for any fault conditions as well as to allow closure remotely of the Isolator onto the Power VT.
15.2 Busbar Protection
132 kV Single Busbar:
The 132 kV single busbar shall be protected by high impedance bus zone scheme (4BZ5900), providing single zone differential protection. Buszone protection is installed to protect the zone that’s not covered by the Feeder protection schemes. The scheme is suitable for application in substations with single busbars with up to 6 bays. The scheme consists of the following functionalities:
GE Multilin MIB‐II relay.
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Variable resistors. ( 2000 ohm resistors have been added due to the fault levels )
Current transformer buswire supervision.
Metrosils.
Protection not healthy indication/alarm.
Breaker fail/bus‐strip.
The Buszone trip will operate all Eskom’s Feeder breakers only.
The scheme conforms to DSP_34‐1294: Specification for a Distribution Bus Zone Protection Scheme.
16 METERING
Statistical & Tariff Metering:
Statistical metering shall be applied to 132kV Feeder 1 on a separate panel. Tariff Metering for PV 1 shall be applied on the 132kV Feeder 2 CT’s using 2 x CT Cores for Main and Check Metering. The following equipment shall be installed:
1 x Stats Measurements Panel that will consist of the 1 x 3MM01C Module with 2 ZMD meters
( 1A, Class 0.5 )
1 x Tariff Measurements Panel that will consist of the 1 x 3MM01C module, 2 x ZMD meters
( 1A, Class 0.2 ) , 1 x ION 8800 Meter and 2 x GSM modems.
Quality of Supply Measurements :
ION 8800 meters shall be installed for Feeder 2 Bay, to record the Quality of Supply of the 132kV supply at the PUC (Point of Utility Connection). These shall be installed on the Tariff Measurements panel. The QOS meters shall be supplied by 1 x 110V DC circuit. The meters shall be wired via the Tariff Metering Check CT core on the Feeder bay. VT supplies to the meter shall be from the 132kV Busbar VT’s.
Remote Interrogation:
A Smartoo GPRS modem shall be installed for the remote downloading of statistical and
tariff metering data. It shall have its own AC circuit from the AC/DC panel to supply the
modem.
A separate Smartoo modem shall be installed for the QOS meter. The QOS modem shall use
the same AC circuit as the Metering modem.
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17 AUXILIARY SUPPLY
DC Systems:
DC Supply:
An 110V, 100Ah Nicad battery bank shall be installed. The design was based on a 12 hour
standby rate. The design does not cater for future feeder bays.
DC Panel:
The new DC Panel shall consist of the following:
1 x 1.8m High 19” Swing frame cabinet
1 x 110V 20A battery charger
1 x DC Interface module
DC Distribution:
The new DC Distribution shall consist of the following:
2 x DC supply modules ( mounted on the AC panel )
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AC SUPPLY:
Station AC Supply:
The station AC supply shall be sourced from the 3 x Line Power VT’s via a Power VTJB. The JB shall have 3 x MCB’s – (20A for the AC Supply to the relay room AC panel, with an aux contact for the trip indication back to control). A 4mm2 4 core cable shall take the single phase AC supplies to the AC panel.
The Power Voltage Transformer is rated at 3,5kVA per phase with a secondary voltage of 230V. It provides 15.22 A at full load. 2 Phases shall be dedicated for the DC Charger. The remaining phase shall be used for all the protection panels, 132kV circuit breaker heaters, modems and a single phase plug socket on the AC panel.
Refer to the schematic attached which indicates the allocation of the circuits for the different loads at the substation. The loading has been calculated such that there isn’t too much of an imbalance between phases. The single phase AC Distribution module used contains 5 circuits for Red phase, 5 Circuit for White and 4 for Blue phase. This needs to be strictly adhered to for the loads coming off these phases.
A Day/Night sensor shall be fitted at the building for the control of the 4 yard lights fed from the Power VT. The yard light control switch shall be used to operate the contactor (mounted in the AC panel) for the 4 yard lights.
The IPP auxiliary supplies shall be used to supply a Yard AC DB ( downrated to 32A) fitted with the changeover which shall feed the yard lights, gate motor and control building lights (via the single phase control room DB ). This DB also caters for the future IPP incomer auxiliary supply input.
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AC Distribution:
The new AC Distribution board shall consist of the following module:
1 x 1Ø AC Module
1 x Plug Socket with Single phase Earth Leakage ( for Laptop use only )
18 SUPERVISORY AND TELECOMMS
Tele‐control equipment is required for communications between the Distribution Control Centre (Master Station) and the substation. All IED’s that are equipped with DNP3 for the serial communications will do so directly to the new D20 RTU. The conventional wall mounted Intermediate Distribution Frame (IDF) will be adopted as there are other alarms to be wired to control.
Supervisory:
System Control will have the following functions available:
Remote control of all breakers and motorised isolators.
Status indication of all breakers.
All the alarms from the applicable protection schemes.
The following shall be installed on site:
D20 RTU
40 way IDF frame
x MOXA RS232‐RS485 Convertors for the serial application
2 x SEL 2830 Single Mode Fibre Optic Transceiver Modems (Male and Female RS232 to Fibre
Convertors ) for the SCADA comms
This shall be achieved via the fibre link between the 2 buildings. Separate communication media convertors may be required for this application as the IPP RTU is then seen as Master and the Eskom RTU as the slave device.
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Telecommunications:
The 2 x 24 way fibre patch panels shall be housed in the Automation/Tele‐comms server cabinet for the incoming 24 core fibre. Fibre shall be ducted using HDPE pipe from the gantry to the building via the cable trenches. A 110/50V DC‐DC Convertor shall be installed in the Telecomms panel for the ADM 50V DC supply.
Single Mode Fibre links shall be installed between the IPP’s D20 RTU’s & Eskom’s Regional Control centre for status monitoring and measurements data. 24 way patch panels are to be provided for this fibre link. They shall link up to the Eskom Telecomms BME at the MTS.
19 SECURITY SYSTEMS
An external contractor shall provide for the supply and installation of the security system. An amount of R 400 000 has been budgeted for the Security systems equipment costs that are to be paid for by the IPP. A Security systems panel shall be provided for by the external contractor for the substation security equipment. This detailed specification shall be provided for in the final design.
20 PANEL FOOTPRINTS
Floor space is required for 16 panels incl. IDF and space for future panels. A Store room has been allocated in the building for the earthing gear and operating equipment.
DESCRIPTION PANEL QTY
AC/DC and Battery Cabinets 4
132kV Feeders 3
Metering Panels 2
Tele‐comms Cabinet / Automation 1
132kV Buszone 1
Security Systems 1
RTU 1
Future panels 3
TOTAL 16
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21 DRAWINGS
The following is a list of proposed drawings that are attached to the design:
Protection Schematic Diagrams
AC/DC Reticulation Schematic Diagram
SCADA Communications Diagram
Relay Panel Label Engraving Diagram
Control Building Panel Layout
22 SUBSTATION AUTOMATION
Refer to attached Design Document for the Automation Specifications.
Substation Automation
Reference Design Document
WCOU Substation Automation – Design Document Base Template – Rev 0 / May 2014
2
Contents 1. Introduction ............................................................................................... 3
2. Substation Automation Requirements ...................................................... 3
2.1 Substation automation scheme installation ......................................... 3
2.2 Bus Zone Protection ........................................................................... 4
2.6.1 4BZ-5600, 5700, 5750, 5800 & 5900 ............................................... 4
2.3 HV Feeder(s) ...................................................................................... 4
2.3.1 4FZ-3920, 3940 ............................................................................ 5
2.4 MV Feeders ........................................................................................ 5
2.4.1 4RF-1100 (Overhead Rural MV Feeder) ...................................... 5
2.5 Telecontrol D20 RTU .......................................................................... 6
2.6 Quality of Supply Meter....................................................................... 6
2.7 DC Cordex Charger ............................................................................ 6
2.8 Auxiliary 12V supply ........................................................................... 7
3. General design requirements .............................................................. 7
4. Commissioning ................................................................................... 7
WCOU Substation Automation – Design Document Base Template – Rev 0 / May 2014
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1. Introduction
Protection, Telecontrol, DC and Metering technologies have in recent years progressed to the
level where protection relays no longer just react to and indicate faults, but also record
detailed information about the state of the load, especially at the time a fault occurs. Detailed
fault information can prove invaluable when analysing the cause of faults and how the system
responds to these faults. Long term information from protection devices can also give
indications of the health of the distribution system which can be used in maintenance planning
and network design. Additionally, devices now provide remote access to internal settings and
controls, allowing a relay to be setup off site. These are all integral parts of substation
automation system currently being implemented in the Western Cape Operating Unit
(WCOU).
The enabling technologies include IP technologies, Data Concentrators, Serial device
servers, networking switches, etc. Typically a Data Concentrator is installed within the
substation as part of the Substation Automation System (SAS) for all data concentration,
protocol translation and as a point for remote access to the substation. In essence a Data
Concentrator is a device installed within the substation with the purpose of interfacing with all
Intelligent Electronic Devices (IEDs) within the substation to retrieve both operational and
non-operational data from the IEDs, and to subsequently communicate this data over to an
enterprise-based data historian which is accessible from the enterprise/corporate network.
Serial device servers are used to link devices at small brick-built substations to a HUB site’s
data concentrator which provides the gateway to the Secure Remote Access System (SRAS)
and data historian. For more details of which sites will have data concentrators or serial
device server, the reader must refer to the “Substation Automation Design criteria” document.
2. Substation Automation Requirements
2.1 Substation automation scheme installation
Substation automation equipment will be installed within the substation to facilitate Remote
Access and Data Retrieval. The site shall be a Hub and the communication medium utilised
shall be ADM. The Data Concentrator and all other Substation automation equipment are
installed within the substation relay room where Substation Automation is to be implemented.
(The Substation Automation drawings - Set 167 shall be completed during the design
phase)
• The Substation Automation equipment shall be housed in the Telecomms and
Substation Automation Panel (standard 19” glass door cabinet) which will be the
concentration point for all data communications.
• The Telecomms and Substation Automation Panel and all Substation Automation
equipment within shall be supplied with power from an 110VDC distribution board
(consisting of double pole MCB’s) in the cabinet. The distribution board itself will be
supplied with power via a dedicated 110VDC line from the AC/DC panel. (Please
refer to the Auxiliaries Cable Block diagram: DWC-Set 159)
• The Data Concentrator will be used to interface with all legacy equipment which
communicates through RS232 or RS485 standards.
• A 5U blanking plate shall be installed as a back plate of the cabinet and will have
installed on it a DIN rail and trunking for equipment and associated MCB’s and
terminals. A RS900 Switch used for Ethernet Communication will also be mounted to
this 5U blanking plate. (Please refer to the Auxiliaries Cable Block diagram - Set
159)
WCOU Substation Automation – Design Document Base Template – Rev 0 / May 2014
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The Substation Automation scheme is interfaced to all the schemes discussed in the following
sections. Should any of the schemes discussed below be used for Protection, DC and
Telecontrol, the requirements specified shall be applied for per scheme to ease the process
of systems integration.
2.2 Bus Zone Protection
Protection Scheme(s) Supplier(s) Relay(s) Protocol(s) Interface(s)
Bus Zone
IST GE Multilin F35 or
GE Multilin MIB II
Modbus Serial comms
RS232/RS485
Table 1 - Bus Zone protection schemes used by Eskom distribution
The schemes catalogued in Table 1 are used by Eskom distribution as the bus zone
protection. Should any of the schemes catalogued in Table 1 be used as the bus zone
protection scheme, the requirements stated in this section shall be applied per feeder
scheme.
2.6.1 4BZ-5600, 5700, 5750, 5800 & 5900
• All GE F35 and MIB II relays have rear EIA485 port to which the Substation
Automation scheme connects. The MIB II relay exposes this on terminals B12, A12
and B11 for the D+, D- and GND connections respectively, whilst the GE F35
exposes these connections on ports D1a, D2a and D3a respectively. Both CAT5E
FTP Solid Core cable(s) shall be pulled between the Bus Zone scheme and the
substation automation panel. Refer to SA drawing set “Cable Block - DWC-167-03”
• A CAT5E FTP Solid Core cable shall be terminated with a RJ45 plug only on the
serial concentrating side and terminated directly on the backplate terminal to which
the communication link has been wired.
• 1x Male RJ45 to DB9 convertors shall be purchased per bus zone scheme, to
connect the serial concentrating device.
• To accommodate this device, the Data Concentrator shall be ordered with the
Modbus communication protocol option.
2.3 HV Feeder(s)
The high voltage protection scheme(s) catalogued in are used within Eskom distribution.
Remote Access and Data Retrieval to these protection schemes is achieved through the
interfaces listed on the far right of Table 2.
Protection Scheme(s) Supplier Relay(s) Protocol(s) Interface(s)
Differential/
distance
protection
scheme
4FZD-
3920,3940
ABB RED670 IEC 61850 100Base-Fx (ST)
REF615 IEC 61850 100Base-Tx (RJ45)
Table 2 - HV Feeder protection schemes used by Eskom distribution
The interfaces listed in Table 2 shall be used to interface the HV feeder scheme(s) to the
SAS. For the successful integration of HV Feeder scheme(s), the requirements itemized in
this section shall apply:
WCOU Substation Automation – Design Document Base Template – Rev 0 / May 2014
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2.3.1 4FZ-3920, 3940
• All the 4FZ-3920, 3940 scheme(s) shall be installed with the optional Rear Mounted
RuggedCom RS900-Hi 8 Port Switch (6 Galvanic/3 Fibre Ports), to link the feeder to
the substation automation network.
• The switch(es) shall be wired into the protection scheme(s) as per the protection
drawing. I.e. The RED 670 protection relay(s) shall be connected to the Ethernet
switch connected within the panel using multimode fibre with ST connectors and the
REF 615 protection relay shall be connected to the Ethernet switch using a standard
RJ45 Ethernet cable
• Two Ethernet RJ45 links shall be connected between front panel And switch for ease
of connection to the substation network – this requirements shall be applied for each
feeder individually
• The feeder IP addresses and related settings shall be supplied by the Substation
Automation Control Plant design engineer(s) to the settings department to be issued
with the standard settings.
• The IEC 61850 option shall be enabled and the regional IEC 61850 datasets loaded
to allow integration to the SAS.
• The Switch within the panel shall be linked to the substation automation network as
detailed in the substation automation drawing “SA Cable Block - DWC-167-03_00”.
• The Data Concentrator shall be ordered with the IEC 61850 MMS Client
communication protocol option.
2.4 MV Feeders
The Medium Voltage protection scheme(s) catalogued in Table 3 are used within Eskom
distribution. Remote Access and Data Retrieval to these protection schemes is achieved
through the interfaces listed on the right of Table 3.
Protection Scheme(s) Supplier(s) Relay(s) Protocol(s) Interface(s)
OH MV
Feeder
Alstom MiCOM P145 Courier Serial comms
RS232/RS485
Cable MV
Feeder
ABB/VAMP Solkor RF/N
(MiCOM
P145)
Courier &
IEC 60870-5-
103
Serial comms
RS232/RS485,
Fibre
Table 3 - HV Feeder protection schemes used by Eskom distribution
The interfaces listed in Table 3 shall be used to interface the MV feeder scheme(s) to the
SAS. For successful integration of MV Feeder scheme(s), the requirements itemized in this
section shall be carefully followed and applied per feeder scheme.
2.4.1 4RF-1100 (Overhead Rural MV Feeder)
For all MiCOM P145 relay(s) used for MV rural feeder protection, the following shall apply:
• All MiCOM P145 relays shall be purchased with the second rear RS-485
communication port (SK4) supporting Courier protocol for remote engineering access.
• Applying the Substation Automation mods in the form of Microstation cells will expose
this port on X3.Kr1 as a standard RJ45 socket. In all instances these cells will be
used to modify the scheme.
• A CAT5E FTP Solid Core cable shall be pulled between each of these protection
panels and the Telecomms and Substation Automation Panel. Refer to SA drawing
set “Cable Block - DWC-167-03”
WCOU Substation Automation – Design Document Base Template – Rev 0 / May 2014
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• All the CAT5E FTP Solid Core cable shall be terminated with a RJ45 plug on both
ends as per the EIA-T568A standard.
• 1x RJ45 to Male DB9 convertor shall be purchased per feeder, to connect the device
to the serial concentrating device. Note that the relay end of this cable will connect
directly with the RJ45 plug into the X3.Kr1 socket.
• To accommodate this device, the Data Concentrator shall be ordered with the Courier
communication protocol option.
2.5 Telecontrol D20 RTU
The GE D20 Remote Terminal Unit (RTU) is the approved product used by the Eskom
Distribution Business to communicate operational data to the SCADA Master. To facilitate
remote access and data retrieval from the D20 RTU, the requirements itemized below shall
be applied:
• Communication to the GE D20 shall be accomplished with two physical connections;
one to the rear Wesmaint serial port (Note its non-standard EIA232 pinout) for remote
access and either a copper Ethernet connection or serial connection to an open rear
SIO port for data communication. In the latter regard the preference shall be towards
an Ethernet connection.
• Two CAT5E FTP Solid Core cables shall be installed from the RTU cabinet to the
Telecomms and Substation Automation Panel and terminate both ends with an RJ45
plug as per the EIA-T568A standard.
• The connection for the Wesmaint port shall require 2x RJ45 to Male DB9 convertors,
and if installed the connection to the SIO port will require an additional 1x RJ45 to
Male DB9 convertor and 1x RJ45 to Female DB9 convertor.
• A second DNP3 slave instance shall be setup on the D20 RTU on either the Ethernet
or SIO port, whichever is catered for.
• To support this device, the Data Concentrator shall support the DNP3 over serial (and
encapsulated over IP) protocol to slave devices.
2.6 Quality of Supply Meter
The ION8800 is the approved quality of supply meter used by the Eskom Distribution. The ION8800 is to be fitted with a standard RJ45 Ethernet port that is used for remote access and data retrieval. To facilitate remote access and data retrieval from the ION8800 quality of supply meter, the requirements itemized below shall be applied:
• The ION8800 quality of supply meter shall be purchased with the following:
a) Ethernet networking model option(s)
b) IEC 61850 MMS server
• A CAT5 cables shall be pulled between the Quality of Supply meter and the
Substation Automation panel. Refer to SA drawing set “Cable Block - DWC-167-03”
• To support this device, the Data Concentrator shall support the IEC61850 MMS client
protocol
2.7 DC Cordex Charger
The Cordex CXC charger is the approved product used by the Eskom Distribution Business.
The Cordex CXC charger is fitted with a standard RJ45 Ethernet socket that is used for
Remote Access and Data Retrieval.
• One CAT5 cables shall be installed between the DC cabinet and the Telecomms and
Substation Automation Panel. Refer to SA drawing set “Cable Block - DWC-167-03”.
• The CAT5E FTP Solid Core cable shall be terminated with an RJ45 plug on both
ends as per the EIA-T568A standard.
WCOU Substation Automation – Design Document Base Template – Rev 0 / May 2014
7
• To support this device, the Data Concentrator shall support the Modbus/TCP
protocol.
2.8 Auxiliary 12V supply
• A 110/12Vdc converter shall be purchased for all sites that require 12Vdc supply for
the MOXA RS232/485 media converter, LL422AB media converter or a Modem used
for the Substation Automation system. Please refer to Substation automation Bill of
Material
• Alternatively, if this is not possible / feasible, a 12V supply shall be sourced from the
RTU power supply through a 4 Core 2.5mm cable to the Telecomms and Substation
Automation Panel.
3. General design requirements
• When a Data Concentrator is installed, it shall always include the following protocols
for integration with enterprise systems:
o DNP3 Slave (Serial and IP)
o OSISoft PI Protocol (PI Interconnect / Native)
• Most current schemes are to be modified by dropping cells on the standard masters.
These mods enable the seamless installation of the SAS on-site by standardising on
the interface exposed by each scheme. Enquire with Project Engineering for which
schemes this will be required.
4. Commissioning
The “Substation Automation Installation Checklist document” shall be submitted to the
Substation automation group on completion of substation installation indicating all the work
done and the tests performed.
Sirius 132kV SubstationPreliminary Design Report
Document Number Revision No Date Page
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SECTION D: CRA FORM
Revision 0 Job Initiation Priority HIGH
General DetailsProject ID IPP147160851
Project Name SCATEC IPP PREFFERED BIDDERS
Job Name Sirius 132kV Substation Job ID IPP147160851-00001
Project Initiator ADMIN Form Registered Date 2015-06-29
Distribution Region / RED WESTERN_REGION
Field Service Area WEST COAST FSA Network Planning Area UPINGTON
Technical Service Area UPINGTON Energy Balancing Code
Customer Service Area WEST COAST Engineering Area WESTERN ENGINEERING AREA
District Municipal Area SIYANDA DISTRICT MUNICIPALITY Local Municipal Area KHARA HAIS (UPINGTON)
Business Process DIRECT CUSTOMER Job CategorySUB-TRANSMISSION S/S ( 44-165 KV )SUB-TRANSMISSION S/S ( 44-165 KV )
Project Description and Motivation
Executive Summary / Motivation
This project is released in order to provide and record the optimised Scope of Works that has been developed to connect the 3 x 75MW preferred bidders that were selected during the DoE's REIPP Round 4 announcement in April 2015. The 3 bidders are located on two properties adjacent to one another as well as being adjacent to the Eskom property where the Solar Park 400/132kV MTS will be located. For efficient use of grid connection assets, it has been agreed by Eskom and the developers, that a combined solution catering for all 3 projects is the technically preferred
option. The previous IPP CRA forms for each 75MW: 144510079, 144510095 and 144514107, will all revert back to this CRA form.
Scope of Work Description
Interdependent Job Details
Job ID Job Name Active Job Form Approved Job Value
IPP147160851-00001 Sirius 132kV Substation CRA FORM Rev: 0 0.00
IPP147160851-00003 Dyasonsklip 132kV Substation CRA FORM Rev: 0 0.00
IPP147160851-00002 Solar Park MTS - Sirius 132kV line CRA FORM Rev: 0 0.00
IPP147160851-00004 Sirius - Dyasonsklip 132kV line CRA FORM Rev: 0 0.00
IPP147160851-00005Solar Park MTS 1 x 132kV feeder bay for Scatec 3 x 75MW PV
CRA FORM Rev: 0 15,239,512.00
Total 15,239,512.00
Interdependent Transmission Assets
Job ID Job Name Value
Total 0.00
Total Parent Project Value 15,239,512.00
Job Dates Job Required Completion Date
2019-06-30
Contracted CRA Form Approval Date
2015-07-31
Project Initiator Manager Acceptance
Role User Type Date Sign Now
INITIATOR MANAGER Not Signed
Page 1 of 3CRA FORM Print
2015/06/29http://172.22.80.135/ACNAC/CAPITALASSIST/Form10/Form10Print.aspx?JobRevi...
Job Name Sirius 132kV Substation
Job ID IPP147160851-00001 WBS Root Element
Economic Sensitivity Analysis (In accordance to the latest FEM model)
Evaluation
Type<--None Selected-->
FEM
RevisionClassification <--None Selected-->
COSTING ASSUMPTIONS - ESCALATION RATES (%)2015/2016 9.00 2016/2017 9.00 2017/2018 9.00 2018/2019 9.00 2019/2020 9.00
Current Overhead % 10.00 Current IDC % 10.14
JOB COSTS (SUPPLY and CAPITAL COSTS including Escalation)WBS Level 2 Contingency Amount % Contingency Capital Amount (Rand) %
ENGINEERING COSTS 0.00 0 0.00 0.00
MATERIALS 0.00 0 0.00 0.00
INTERNAL CONTRACTS 0.00 0 0.00 0.00
EXTERNAL CONTRACTS 0.00 0 0.00 0.00
COMMISSIONING 0.00 0 0.00 0.00
OVERHEADS 0.00 0.00
IDC 0.00 0.00
LAND AND RIGHTS 0.00 0 0.00 0.00
Capital Cost Subtotal 0.00 0.00 0.00 0.00
Supply Cost Subtotal 0.00 0.00 0.00 100.00
Total Cost (CRA Form) 0.00 0.00 0.00 100%
Pre-Engineering Approved
Total Pre-Engineering Approved R 0.00
Long Lead Time Material Approved
Total Long Lead Time Material Approved (Refer to Power Office Long Lead details) R 0.00
Contributor/Customer Name
% Customer Contribution (Capital Only)
0.00 % Standard Supply 0.00
Guarantee Amount 0.00 Guarantee Status
JOB SCHEDULEContracted DRA
Form Approval Date
Job Required Completion Date
2019-06-30
Job Contracted Completion
Date
Schedule Variance Explanation
Environmental Status <--None Selected-->
Page 2 of 3CRA FORM Print
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Job Name Sirius 132kV Substation
Job ID IPP147160851-00001
Physical Statistics
NACVC KPIs KPI for this Job Comments
Cost per transformer (sub-transmission)
Cost per transformer (reticulation)
Cost per km line (44kV to 165kV)
Cost per km line (11kV to 33kV)
Electrification Quantity Total Cost Cost / Connection
Connections 0.00
Job Acceptance
Role User Type Date Sign Now
PROGRAM MANAGER Not Signed
DEFINITION MANAGER Not Signed
TEF Minutes
NSM / RIC APPROVAL FOR EXPENDITURE R 0.00 0.00 %
RIC Meeting Date RIC Meeting Number
NSM / RIC Minutes
Role User Type Date Sign Now
Page 3 of 3CRA FORM Print
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Sirius 132kV SubstationPreliminary Design Report
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SECTION E: Project Schedule
ID Task Name Duration Start Finish
0 Sirius Substation - IPP147160851-00001 740 days Mon 15/06/01 Sun 18/04/01
1 Plan 229 days Mon 15/06/01 Thu 16/04/14
2 CRA Approved 22 days Mon 15/06/01 Tue 15/06/30
3 TEF Approved 1 day Thu 15/07/30 Thu 15/07/30
4 Receipt of Budget Quotation (from Eskom) 1 day Tue 15/09/01 Tue 15/09/01
5 Financial Close 64 days Wed 15/09/02 Mon 15/11/30
6 Detailed Design Phase (Eskom Substation) 98 days Tue 15/12/01 Thu 16/04/14
7 Detailed Design Phase (IPP Substation) 65 days Fri 16/01/01 Thu 16/03/31
8 Do 29 days Tue 16/11/15 Fri 16/12/23
9 Site Establishment 5 days Tue 16/11/15 Mon 16/11/21
10 Mobilize Plant, Equipment and Personnel 24 days Tue 16/11/22 Fri 16/12/23
11 Execution Phase 326 days Mon 17/01/02 Sun 18/04/01
12 Platform Construction 108 days Mon 17/01/02 Wed 17/05/31
13 Control Room Construction (Eskom and IPP) and equipment installation 44 days Thu 17/06/01 Tue 17/08/01
14 IPP substation Commissioning 30 days Fri 17/09/01 Thu 17/10/12
15 Eskom substation Commissioning 31 days Mon 18/01/01 Mon 18/02/12
16 Energise Substation (Eskom ready to energise) 1 day Thu 18/03/01 Thu 18/03/01
17 Commercial Operation 1 day Sun 18/04/01 Sun 18/04/01
Robin Buske
TAP CONSULTANTS
Eskom
ConsultantsConsultants
ConsultantsConsultants
IPP Sub-contractorsIPP Sub-contractors
IPP Sub-contractorsIPP Sub-contractors
IPP Sub-contractorsIPP Sub-contractors
IPP Sub-contractorsIPP Sub-contractors
EskomEskom
EskomEskom
IPPIPP
MayJun Jul AugSepOctNovDecJanFebMarAprMayJun Jul AugSepOctNovDecJanFebMarAprMayJun Jul AugSepOctNovDecJanFebMarAprMa5 Qtr 2 2015 Qtr 3 2015 Qtr 4 2016 Qtr 1 2016 Qtr 2 2016 Qtr 3 2016 Qtr 4 2017 Qtr 1 2017 Qtr 2 2017 Qtr 3 2017 Qtr 4 2018 Qtr 1 2018
Dyasonsklip SS and Sirius SS.mpp Page 1
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SECTION F: Key Role Players
WESTERN CAPE OPERATING UNIT Job ID: IPP147160851 - Key Role Players
Name Telephone Project Initiator: Robin Buske 021 980 3012 Project Engineer: Mike Stockdale 021 980 3086 Project Co-ordinator: Anthony Japtha 021 980 3458 Programme Manager: Ryan De Leeuw 021 980 3048 Electricity Delivery: Erlind Segers Leon Drotsché Field Services: Manie Kotze Mario Eygelaar (TSO for Responsible Depot) Koos Van Zyl (CNC supervisor for Upington) Plant: Khethiwe Nofuya Project Engineering: Zakes Mpela Land Development: Debbie Harding Network Operations: Llewellyn Bok Network Planning: Christopher Fakudze Technology & Quality: Vacant
Core members and their respective authorised representatives are shown in blue.
#Note: Telephone numbers only for the top 4 names!
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SECTION K: PRIMARY PLANT DRAWINGS
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SECTION L: SECONDARY PLANT DRAWINGS
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SECTION M: ARCHITECTURAL LAYOUT
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SECTION N: EARTHGRID DESIGN REPORT
Sirius Substation Earthgrid Design Rev 0
PROJECT NUMBER: P1902-3828 0
SIRIUS SUBSTATION EARTHGRID DESIGN NORTHERN CAPE REGION
PROJECT NO. : P1902-3828
Prepared by: Trans-Africa Projects
Rev 0 July 2015
COPYRIGHT IN THIS REPORT IS RESERVED. NO PUBLICATION OR DISSEMINATION OF ITS CONTENTS IS ALLOWED WITHOUT WRITTEN PERMISSION
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PROJECT NUMBER: P1902-3828 2
Contents
1 INTRODUCTION ...................................................................................................................... 3
2 NETWORK DIAGRAM ............................................................................................................. 4
3 SUBSTATION LOCATION ........................................................................................................ 5
4 FAULT CURRENTS .................................................................................................................... 6
5 APPROACH AND ASSUMPTIONS .......................................................................................... 7
5.1 SOFTWARE .............................................................................................................................. 7 5.2 SOIL MODEL ........................................................................................................................... 7 5.3 ADDITIONAL ASSUMPTIONS AND CRITERIA .................................................................................. 7
6 RESULTS AND CONCLUSION ................................................................................................. 9
7 WENNER DATA ..................................................................................................................... 10
8 SOFTWARE SUGGESTED SOIL MODEL (BASED ON WENNER DATA) .................................. 10
9 SIMULATION RESULTS (24KA FAULT CURRENT – 0.5M DEEP EARTHGRID) ......................... 11
9.1 TOUCH VOLTAGES PLOT ......................................................................................................... 11 9.2 UNSAFE TOUCH VOLTAGES PLOT ............................................................................................. 11 9.3 STEP VOLTAGES PLOT ............................................................................................................. 12 9.4 UNSAFE STEP VOLTAGES PLOT ................................................................................................. 12
10 SIMULATION RESULTS (40KA FAULT CURRENT – 0.5M DEEP EARTHGRID) ....................... 14
10.1 TOUCH VOLTAGES PLOT ....................................................................................................... 14 10.2 UNSAFE TOUCH VOLTAGES PLOT ........................................................................................... 14 10.3 STEP VOLTAGES PLOT........................................................................................................... 15 10.4 UNSAFE STEP VOLTAGES PLOT ............................................................................................... 15
11 PROPOSED EARTHGRID LAYOUT ....................................................................................... 16
12 SOFTWARE REPORT (24KA FAULT LEVEL – 0.5M DEEP EARTHGRID) ................................. 16
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1 INTRODUCTION
Scatec Solar has been awarded 3 x 75MW Solar PV projects, which are all located a short distance outside the town of Upington in the Northern Cape. The Solar PV sites are called Sirius 1, Sirius 2 and Sirius 1.
A substation will be constructed on the Sirius 1 site (called Sirius substation) and a separate substation on the Dyasonsklip 1 site (Dyasonsklip substation). Sirius substation will act as a collector station for the power generated from the new Sirius 1 75MW IPP solar PV generation facility, as well as for the 132kV infeed from Dyasonsklip substation. The output from Sirius substation will then be fed into the Solar Park MTS, which is located a short distance away.
There is an existing 132kV network in the region, but there is limited capacity for new connections and the existing connections are located some distance away from these sites. To facilitate connection from these 3 x 75MW Solar PV sites and other future IPP projects planned for the region, Eskom will be constructing a new Main Transmission Substation just outside Upington with appropriate step-up transformers (132kV to 400kV).
This report details the methodology that was used to evaluate and design the earthgrid at Sirius substation.
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2 NETWORK DIAGRAM
Figure 1: Existing Network Configuration
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Figure 2: Proposed Network Diagram
3 SUBSTATION LOCATION
The Sirius substation is located on the Sirius 1 PV plant property and is approximately 20km south west of Upington. The site is accessed via a gravel road.
The proposed approximate co-ordinates for Sirius substation are provided below:
Latitude: 28°33'6.48"S
Longitude: 21°6'20.07"E
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Figure 3: Sirius substation location
4 FAULT CURRENTS
The fault levels as obtained from the network planner are given below:
Busbars 1 Phase Fault (kA) 3 Phase Fault (kA) 132kV (at Solar Park MTS) 39.9 32.5 132kV (at Sirius) 21.6 24.2
Sirius SS location
Upington MTS (proposed)
Upington town
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5 APPROACH AND ASSUMPTIONS
5.1 Software
This design was simulated using AutoGrid Pro® version 14.0.380 with a uniform soil capacity. http://www.sestech.com/products/softpackages/autogridpro.htm
5.2 Soil model
The soil model based on the Wenner measured data indicated a 2 layer soil model with a top layer resistivity of approximately 212 Ω-m (to a depth of 3.9m) and a bottom layer resistivity of approximately 395 Ω-m.
The calculated soil resistivity model based on the measured data, as produced by the CDEGS software is shown in section 8.
5.3 Additional assumptions and criteria
The main assumptions/criteria used in performing the simulation are listed below:
- The fault level provided by Eskom Net Ops is 21.6kA at the 132kV busbar inside Sirius substation. In order to be more conservative a fault level of 24kA was used to determine the safety of the earthgrid under fault conditions
- The main source for the fault current would be from the Solar Park MTS - The soil model based on the Wenner measured data was used in the
simulations - The earthgrid spacing has been designed with 5m x 5m spacing
between conductors. The earthgrid has been designed to extend outside the perimeter fence by 2m. This was done to eliminate touch potential issues at the perimeter fence and to attempt to reduce the Ground Potential Rise (GPR).
- A geotechnical study that was done on the Sirius site indicated that there is a presence of hard rock not far below the surface (at approximately 1m depth). To avoid having to install the earthgrid in this hard rock all the simulations have been done assuming a depth of 0.5m for the earthgrid
- In doing the simulations the fault level was increased incrementally to determine the upper limit at which the Sirius earthgrid remains safe for step and touch potentials
- The 2 overhead earthwires on the Sirius-Solar Park MTS 132kV line were modelled as part of the circuit and have been included in all the simulations
- The 132kV line from Sirius to Solar Park MTS was assumed to be 3km long
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- Two different simulations were performed, as follows (including the overhead earthwires):
o Simulation with the earthgrid at a depth of 0.5m at 24kA
o Simulation with the earthgrid at a depth of 0.5m at 40kA (this is the limit at which the touch potentials start to become unsafe at the perimeter fence)
- The average soil resistivity along the transmission line between Sirius substation and Solar Park MTS was assumed to be 100 Ω-m.
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6 RESULTS AND CONCLUSION
The designed earthgrid with 5m x 5m spacing is safe for step and touch potentials at a fault level of 24kA. The GPR is however, at 6.8kV, which is above the safe limit of 5kV. The only means of lowering the GPR will be to increase the size of the earthgrid.
The touch potentials start to become unsafe at the perimeter fence when the fault current exceeds 40kA.
Both the overhead earthwires are a definite requirement in order to distribute most of the fault current away from Sirius substation. This helps to reduce the size and density of the earthgrid required at Sirius, as it does not have to be designed to carry the full fault current.
The earthgrid design proposed here is safe for the fault levels provided by Eskom and it has the capacity to withstand a fault current of up to 40kA from the source side before the touch potentials become unsafe. Unfortunately the GPR is above the safe limit, but possible solutions will be further investigated at the final design stage to determine if there is a feasible way of reducing the GPR. This may require the earthgrid design proposed here to be reviewed and amended at the final design stage.
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7 WENNER DATA
Soil resistance measurements were taken using a Megger DET4TC2. Two sets of measurements were taken as indicated in Figure 4. The measurement data is shown in the table below.
Spacing Resistance (Ω)
0.5m 63Ω
1m 31Ω
2m 23Ω
3m 17Ω
4m 9Ω
6m 4.89Ω
8m 10Ω
10m 7Ω
14m 7Ω
18m 15Ω
22m 7Ω
Figure 4: Wenner measured data
8 SOFTWARE SUGGESTED SOIL MODEL (BASED ON WENNER DATA)
Figure 6: Soil resistivity model derived from Wenner measurements
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9 SIMULATION RESULTS (24KA FAULT CURRENT – 0.5M DEEP EARTHGRID)
9.1 Touch Voltages Plot
Figure 7: Touch Voltages plot (All) for 0.5m deep earthgrid at 24kA fault current
9.2 Unsafe Touch Voltages Plot
Figure 8: Unsafe touch voltages plot for 0.5m deep earthgrid at 24kA fault current
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9.3 Step Voltages Plot
Figure 9: Step Voltages plot (All) for 0.5m deep earthgrid at 24kA fault current
9.4 Unsafe Step Voltages Plot
Unsafe step voltages plot for 0.5m deep earthgrid at 24kA fault currentFigure 10:
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Reviewing the Touch and Step potential plots shown in Figures 7 through 10 it is clear that there are no unsafe touch or step potentials across the substation under fault conditions. The GPR is higher than the safe limit at 6.8kV (refer section 12 for the software report).
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10 SIMULATION RESULTS (40KA FAULT CURRENT – 0.5M DEEP EARTHGRID)
10.1 Touch Voltages Plot
Figure 11: Touch Voltages plot (All) for 0.5m deep earthgrid at 40kA fault current
10.2 Unsafe Touch Voltages Plot
Figure 12: Unsafe touch voltages plot for 0.5m deep earthgrid at 40kA fault current
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10.3 Step Voltages Plot
Figure 13: Step Voltages plot (All) for 0.5m deep eathgrid at 40kA fault current
10.4 Unsafe Step Voltages Plot
Figure 14: Unsafe step voltages plot for 0.5m deep earthgrid at 40kA fault current
Reviewing the Touch and Step potential plots shown in Figures 11 through 14 above, it is clear that there are no unsafe touch and step potentials inside the substation under fault conditions (assuming a 40kA fault current from the
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source). The touch potentials at the perimeter fence are at the point of becoming unsafe.
11 PROPOSED EARTHGRID LAYOUT
Figure 15: Isometric view of the proposed Sirius earthgrid layout
12 SOFTWARE REPORT (24KA FAULT LEVEL – 0.5M DEEP EARTHGRID)
Report #1: ******************************************************************************************************************************* AUTOGRID PRO USER INPUT DATA REPORT Creation Date/Time: 17 Jul 2015/07:35:45 ******************************************************************************************************************************* ---------------------------------------------------------------- Graphics option chosen ---------------------------------------------------------------- Computation Plots Touch Voltages Show All Values Show Unsafe Values Above Selected Safety Threshold
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Step Voltages Show All Values Show Unsafe Values Above Selected Safety Threshold Soil Resistivity Measurement Interpretation No configuration plots requested ---------------------------------------------------------------- Types of plot selected ---------------------------------------------------------------- Computation Plots 2D Spot End of Report #1 Report #2: ******************************************************************************************************************************* AUTOGRID PRO SYSTEM INPUT DATA REPORT Creation Date/Time: 17 Jul 2015/07:35:45 ******************************************************************************************************************************* ------------------------------------------------------------------------------------------------------------------------------- Project Summary ------------------------------------------------------------------------------------------------------------------------------- Run Identification .......................... 0.5m deep grid (2m outside fence) - corrected EW (22kA) System of Units ............................. Metric Radius Measured in .......................... Meters Frequency ................................... 50 Hz ------------------------------------------------------------------------------------------------------------------------------- Soil Structure (deduce soil structure from field resistivity measurements) ------------------------------------------------------------------------------------------------------------------------------- Measurement method...........................Wenner Type of measurement..........................Resistance Probe depth option...........................Ignore Probe Depth Measurement (Meters) Apparent Resistance R Number (Meters) (Ohms) ---------------------------------------------------------------- R1 0.5 63 R2 0.5 63
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R3 0.5 63 R4 1 31 R5 1 31 R6 1 31 R7 2 23 R8 2 23 R9 2 23 R10 3 17 R11 3 17 R12 3 17 R13 4 9 R14 4 9 R15 4 9 R16 6 4.88 R17 6 4.9 R18 6 4.89 R19 8 10 R20 8 10 R21 8 10 R22 10 7 R23 10 7 R24 10 7 R25 14 7 R26 14 7 R27 14 7 R28 18 15 R29 18 15 R30 18 15 R31 22 2 R32 22 2 R33 22 2 ------------------------------------------------------------------------------------------------------------------------------- Network Fault Current Distribution ------------------------------------------------------------------------------------------------------------------------------- Average soil characteristics along electric lines: Resistivity(Ohm-m) .......................... 100 Relative Permeability (p.u.) ................ 1 Central site definition: Name ........................................ Sirius Ground Impedance (To be deduced from grounding computations) ------------------------------------------------------------------------------------------------------------------------------- Safety ------------------------------------------------------------------------------------------------------------------------------- Determine Safety Limits for Touch and Step Voltages Maximum GPR of Grid (Volts) ................. 5000 Safety Threshold for Touch Voltages ......... 670.4 V
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Safety Threshold for Step Voltages .......... 2218.1 V Automatic Generation of Observation Points. Grid Border Offset for Touch Voltages ....... 5 m Grid Border Offset for Step Voltages ........ 5 m End of Report #2 Report #3: =========< R E S I S T I V I T Y ( SYSTEM INFORMATION SUMMARY ) >========= Run ID......................................: 0.5m deep grid (2m o System of Units ............................: Meters Soil Type Selected..........................: Multi-Layer Horizontal RMS error between measured and calculated...: 37.6774 in percent resistivities (Note RMS=SQRT(average(Di**2)). <--- LAYER CHARACTERISTICS --> Reflection Resistivity Layer Resistivity Thickness Coefficient Contrast Number (ohm-m) (Meters) (p.u.) Ratio ====== ============== ============== ============ ============ 1 Infinite Infinite 0.0 1.0 2 211.3758 3.868677 -1.0000 0.21138E-17 3 394.6812 Infinite 0.30246 1.8672 End of Report #3 Report #4: **************************************************************** Resistivity Comparison Creation Date/Time: 17 Jul 2015/07:35:45 **************************************************************** Comparison of Measured & Computed Apparent Resistivities ======================================================== C1-C2 SPACING APPARENT RESISTIVITY DISCREPANCY POINT (meters) MEASURED COMPUTED Di (percent) ===== ============= ======== ======== =========== 1 1.50000 197.9 211.5 6.84 2 1.50000 197.9 211.5 6.84 3 1.50000 197.9 211.5 6.84 4 3.00000 194.8 212.2 8.92 5 3.00000 194.8 212.2 8.92 6 3.00000 194.8 212.2 8.92 7 6.00000 289.0 216.9 24.95 8 6.00000 289.0 216.9 24.95 9 6.00000 289.0 216.9 24.95 10 9.00000 320.4 226.3 29.39 11 9.00000 320.4 226.3 29.39 12 9.00000 320.4 226.3 29.39
Sirius Substation Earthgrid Design Rev 0
PROJECT NUMBER: P1902-3828 20
13 12.0000 226.2 238.7 5.51 14 12.0000 226.2 238.7 5.51 15 12.0000 226.2 238.7 5.51 16 18.0000 184.3 265.4 43.99 17 18.0000 184.7 265.4 43.70 18 18.0000 184.0 265.4 44.29 19 24.0000 502.7 288.9 42.52 20 24.0000 502.7 288.9 42.52 21 24.0000 502.7 288.9 42.52 22 30.0000 439.8 307.7 30.05 23 30.0000 439.8 307.7 30.05 24 30.0000 439.8 307.7 30.05 25 42.0000 615.8 333.7 45.80 26 42.0000 615.8 333.7 45.80 27 42.0000 615.8 333.7 45.80 28 54.0000 1696. 350.0 79.37 29 54.0000 1696. 350.0 79.37 30 54.0000 1696. 350.0 79.37 31 66.0000 276.5 360.7 30.48 32 66.0000 276.5 360.7 30.48 33 66.0000 276.5 360.7 30.48 ========= Average discrepancy: 31.62% RMS ERROR BETWEEN MEASURED AND CALCULATED RESISTIVITIES : 37.68 percent *NOTE* RMS = SQRT( average(Di**2) ) End of Report #4 Report #5: **************************************************************** List of Materials Creation Date/Time: 17 Jul 2015/07:35:45 **************************************************************** Interconnection / Bonding Nodes ....................... 460 Extent of Grounding System ............................ 6660 (Square Meters) Surface Layer Thickness ............................... 10 (Centimeters) Volume of Insulating Layer ............................ 666 (Cubic meters) Wet Resistivity of Insulating Surface Layer ........... 3000 (Ohm-m) Grounding System Data Number of Rods Length (m) Diameter (m) ---------------------------------------------------------------- None - - Number of Grid Conductors Length (m) Diameter (m) ----------------------------------------------------------------
Sirius Substation Earthgrid Design Rev 0
PROJECT NUMBER: P1902-3828 21
20 90 0.01 23 74 0.01 Total Length of Grid Conductors (m) Diameter (m) ---------------------------------------------------------------- 3502 0.01 End of Report #5 Report #6: Date of run (Start) = Friday,17 July 2015 Starting Time = 7:35:46 AM >>Safety Calculation Table System Frequency....................................: 50.000(Hertz) System X/R..........................................: 20.000 Surface Layer Thickness.............................: 10.000(cm) Number of Surface Layer Resistivities...............: 10 Starting Surface Layer Resistivity..................: NONE Incremental Surface Layer Resistivity...............: 500.00(ohm-m) Equivalent Sub-Surface Layer Resistivity........... .: 211.38(ohm-m) Body Resistance Calculation.........................: IEEE Std.80-2000 Fibrillation Current Calculation....................: IEEE Std.80-2000 (50kg) Foot Resistance Calculation.........................: IEEE Std.80-2000 User Defined Extra Foot Resistance..................: 0.0000 ohms ============================================================================== Fault Clearing Time (sec) | 0.125 | 0.250 | 0.500 | +----------------------------+---------------+---------------+---------------+ Decrement Factor | 1.224 | 1.120 | 1.062 | Fibrillation Current (amps)| 0.328 | 0.232 | 0.164 | Body Resistance (ohms)| 1000.00 | 1000.00 | 1000.00 | ============================================================================== ========================================================================== | Fault Clearing Time | | Surface |-----------------+-----------------+-----------------| Foot | Layer | 0.125 sec. | 0.250 sec. | 0.500 sec. | Resist | Resist |-----------------|-----------------|-----------------| ance | ivity | Step | Touch | Step | Touch | Step | Touch | 1 Foot | (ohm-m) |Voltage |Voltage |Voltage |Voltage |Voltage |Voltage | (ohms) | |(Volts) |(Volts) |(Volts) |(Volts) |(Volts) |(Volts) | | ========================================================================== NONE | 622.0| 356.5| 480.8| 275.5| 358.6| 205.5| 660.5| |---------+--------+--------+--------+--------+--------+--------+--------+ 500.0| 972.7| 444.1| 751.9| 343.3| 560.9| 256.1| 1315.1| |---------+--------+--------+--------+--------+--------+--------+--------+ 1000.0| 1554.4| 589.6| 1201.6| 455.7| 896.3| 340.0| 2400.5|
Sirius Substation Earthgrid Design Rev 0
PROJECT NUMBER: P1902-3828 22
|---------+--------+--------+--------+--------+--------+--------+--------+ 1500.0| 2129.5| 733.3| 1646.1| 566.9| 1227.9| 422.9| 3473.6| |---------+--------+--------+--------+--------+--------+--------+--------+ 2000.0| 2702.6| 876.6| 2089.1| 677.6| 1558.4| 505.5| 4543.1| |---------+--------+--------+--------+--------+--------+--------+--------+ 2500.0| 3274.9| 1019.7| 2531.5| 788.2| 1888.4| 588.0| 5610.9| |---------+--------+--------+--------+--------+--------+--------+--------+ 3000.0| 3846.8| 1162.7| 2973.6| 898.7| 2218.1| 670.4| 6678.0| |---------+--------+--------+--------+--------+--------+--------+--------+ 3500.0| 4418.4| 1305.6| 3415.4| 1009.2| 2547.7| 752.8| 7744.6| |---------+--------+--------+--------+--------+--------+--------+--------+ 4000.0| 4989.8| 1448.4| 3857.1| 1119.6| 2877.2| 835.2| 8810.9| |---------+--------+--------+--------+--------+--------+--------+--------+ 4500.0| 5561.1| 1591.3| 4298.8| 1230.0| 3206.6| 917.5| 9876.9| |---------+--------+--------+--------+--------+--------+--------+--------+ * Note * Listed values account for short duration asymmetric waveform decrement factor listed at the top of each column. End of Report #6 Report #7: DATE OF RUN (Start)= DAY 17 / Month 7 / Year 2015 STARTING TIME= 7:35:46:41 ===========< G R O U N D I N G ( SYSTEM INFORMATION SUMMARY ) >=========== Run ID......................................: 0.5m deep grid (2m o System of Units ............................: Metric Earth Potential Calculations................: Single Electrode Case Type of Electrodes Considered...............: Main Electrode ONLY Soil Type Selected..........................: Multi-Layer Horizontal SPLITS/FCDIST Scaling Factor................: 3645.7 1 1 MULTI-LAYER EARTH CHARACTERISTICS USED BY PROGRAM LAYER TYPE REFLECTION RESISTIVITY THICKNESS No. COEFFICIENT (ohm-meter) (METERS) ----- ------ ------------- ------------- ------------- 1 Air 0.00000 0.100000E+21 Infinite 2 Soil -0.999990 211.376 3.86868 3 Soil 0.302456 394.681 Infinite 1 CONFIGURATION OF MAIN ELECTRODE =============================== Original Electrical Current Flowing In Electrode..: 1.0000 amperes Current Scaling Factor (SPLITS/FCDIST/specified)..: 3645.7
Sirius Substation Earthgrid Design Rev 0
PROJECT NUMBER: P1902-3828 23
Adjusted Electrical Current Flowing In Electrode..: 3645.7 amperes Number of Conductors in Electrode.................: 43 Resistance of Electrode System....................: 1.8674 ohms SUBDIVISION =========== Grand Total of Conductors After Subdivision.: 1197 Total Current Flowing In Main Electrode......: 3645.7 amperes Total Buried Length of Main Electrode........: 3502.0 meters EARTH POTENTIAL COMPUTATIONS ============================ Main Electrode Potential Rise (GPR).....: 6808.1 volts End of Report #7 Report #8: DATE OF RUN (Start)= DAY 17 / Month 7 / Year 2015 STARTING TIME= 7:35:46:56 =======< FAULT CURRENT DISTRIBUTION ( SYSTEM INFORMATION SUMMARY ) >======= Run ID.......................................: 0.5m deep grid (2m o Central Station Name.........................: Sirius Total Number of Terminals....................: 1 Average Soil Resistivity.....................: 100.00 ohm-meters Printout Option..............................: Detailed 1 Central Station: Sirius Ground Resistance........................: 1.8674 ohms Ground Reactance.........................: 0.0000 ohms 1 Terminal No. 1 : Solar Park M Number of Sections..............: 15 Ground Impedance................: 10.000 +j 0.0000 ohms Source Current..................: 24000. Amps / 0.0000 degrees Neutral Connection Impedance....: 0.0000 +j 0.0000 ohms Span Length.....................: 230.00 m 1 TERMINAL GROUND SYSTEM (Magn./Angle) Term: 1 Total Earth Current...: 1339.4 Amps / -136.84 deg. Earth Potential Rise..: 13394. Volts / -136.84 deg. Average Resistivity...........: 100.00 Ohm-meters
Sirius Substation Earthgrid Design Rev 0
PROJECT NUMBER: P1902-3828 24
Grid Impedance................: 1.8674 +j 0.0000 Ohms < Magnitude / Angle > Total Fault Current...........: 24000. Amps / 0.0000 degrees Total Neutral Current.........: 21401. Amps / -6.4666 degrees Total Earth Current...........: 3645.7 Amps / 41.385 degrees Ground Potential Rise (GPR)...: 6808.1 Volts / 41.385 degrees End of Report #8 Report #9: ---------------------------------------------------------------- Report for Ampacity Function Creation Date/Time: 17 Jul 2015/07:35:46 ---------------------------------------------------------------- CDEGS Conductor Ampacity Calculation (per IEEE Standard 80) ---------------------------------------------------------------- Computation Results ---------------------------------------------------------------- Use 250°C if mechanical considerations do not allow annealing for the conductor (e.g., connections of aboveground conductors), no matter how the connections are made. Also for pressure type connections if no temperature data is available: Minimum Conductor Size: ==================== 195.1995 MCM 98.8852 mm² 0.2209 in (radius) 5.6104 mm (radius) Use 450°C for brazed conductors: Minimum Conductor Size: ==================== 157.4637 MCM 79.7689 mm² 0.1984 in (radius) 5.0390 mm (radius) Other temperatures may apply for pressured type conductors Use fusing temperature of conductor otherwise (e.g., direct-buried conductors with exothermic welded joints): 1083.0000 °C (fusing temperature) Minimum Conductor Size: ==================== 122.1500 MCM 61.8794 mm² 0.1747 in (radius) 4.4382 mm (radius) Input Data: ====================
Sirius Substation Earthgrid Design Rev 0
PROJECT NUMBER: P1902-3828 25
Symmetrical RMS Current Magnitude: 24 kA Maximum Fault Duration: 0.5 s Ambient Temperature: 20 °C Conductor Type: Copper, annealed soft drawn (100% conductivity) Decrement Factor: 1.0517 X/R: 20 Frequency: 60 Hz Material Constants of Conductor: ==================== Name: Copper, annealed soft drawn (100% conductivity) Reference Temperature for Material Constants: 20 °C Thermal Coefficient of Resistivity at Reference Temperature: 0.00393 1/°C Fusing Temperature of Conductor: 1083 °C Resistivity of Conductor at Reference Temperature: 1.72 mW×cm Thermal Capacity per Unit Volume: 3.42 J/cm³ · °C ---------------------------------------------------------------- End of Report #9