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20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 1
Vishay ESTA
Welcome To
Vishay ESTA Power Capacitors Division
Training for Suzlon Team
Pondicherry20th January 2005
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 2
Vishay ESTA
ESTA AC Capacitors in cylindrical aluminium casings have been designed especially
for Power Factor Correction in heavy duty applications
such as
wind turbine plants
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 3
Vishay ESTA
Required capacitor output for Power Factor Correction
Output, Capacitance & Current of Capacitors
Standards for Low Voltage (LV) Capacitors
Life Expectancy
ESTA LV Tubular Can Type Capacitors, MKP-Technology
Installation, Operating and Maintenance Instructions
Supplied Types
Table of Contents
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 4
Vishay ESTA
WHAT MAKES A CAPACITOR ??
ELECTRICAL ENERGY IN FORM OF “CHARGES” CAN BE STORED & WITHDRAWN FROM THIS DEVICE USING TERMINATION WIRES/LEAD WIRES
CAPACITOR BASICS
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 5
Vishay ESTA
dielectric layer,dielectric layer,thickness "d"thickness "d"
Conducting plate, Conducting plate, area "a"area "a"
Capacitors are made using two conducting plates(electrode), separated by an insulating (dielectric) layer
It is essential that the electrodes are in full contact with theentire dielectric area.
CAPACITOR BASICS
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 6
Vishay ESTA
CAPACITOR BASIC
BASIC FORMULA FOR CAPACITANCE
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 7
Vishay ESTA
CAPACITOR BASIC
Pe rmit t ivityVac uum 1 . 0D ry air 1 . 0 0 0 5 9
Plas t ic fi lm 2 . 0 - 3 . 5Impre gnate d pape r 2 . 5 - 6 . 0
Mic a and glas s 4 . 0 - 7 . 0Ce ramic ( s table ) up to 1 0 0
Ce ramic ( se mi-s table ) up to 1 2 0 0Aluminium o x ide 7 +
Tantalum o x ide 1 1 +
RELATIVE PERMITTIVITY
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 8
Vishay ESTA
CAPACITOR BASICS
BASIC CAPACITOR EQUATION
CAPACITANCE =AREA (of the dielectric)
THICKNESS OF DIELECTRIC
The Thickness of the dielectric is directly related to the voltage rating,
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 9
Vishay ESTA
ESTA LV Tubular Can Type
Capacitors
MKP-Technology
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 10
Vishay ESTA
MKP: „Metallized Polypropoylene Film“
Metallization(Electrode)
PP Film(Isolation)
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 11
Vishay ESTA
Winding Elements
A winding element consists oftwo displaced metallized polypropylene films,wound together.
PP Film(Isolation)
Metallization(Electrode)
Due to the displacement, only one film (electrode)will be electrically connected on one side of theelement.
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 12
Vishay ESTA
Electric contact of the electrodes is done by joiningeach front surface of the winding elements by means of metal spray process.
This process is called „Schooping“.
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 13
Vishay ESTA
Schooping is done here
Side view:
Top view:
PP-Film
Flame-sprayedcontact area(Schooping)
Metallizing
Cut on element:
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 14
Vishay ESTA
Winding elements with schooping
Top View
Side View
Mandrel
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 15
Vishay ESTA
PP Film
Metallization(Electrode)
TOP VIEW
Self Healing Film Technology
Decrease of capacitance per self-healing processis less than 100pF
Evaporated Area
Breakdown Puncture
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 16
Vishay ESTA
3-phase tubular can type capacitor:winding elements connected in DELTA
1
2
3
1
3
2
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 17
Vishay ESTA
Low - loss, self healing MKP film technology
ALL-PHASE overpressure tear-off fuses
Safety Features of ESTA L.V. Tubular Can Type Capacitors
At the end of service life, due to inadmissable electrical or thermal load, the active capacitor elements are totally disconnected from the supply. No risk of bursting capacitor.
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 18
Vishay ESTA
ALL-PHASE Overpressure Tear-Off Fuse System
Gasing caused by a Defect
Connection Stripesoutside the windingelements
Terminals
OverpressureWinding Element
Operating condition
All-Phase Disconnection
Torn-off condition
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 19
Vishay ESTA
ESTA‘s L.V. tubular can type capacitors are
burstproof,as confirmed by independent international
inspection centres such as UL and ULc
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 20
Vishay ESTA
• High pulse current withstand capability: 300 x In
• Overcurrent up to 50 A(84.4 mm diameter, oil-filled version, at maximum 65°C casing temperature)
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 21
Vishay ESTA
• Deep-drawn aluminium tubular casing 64 and 84.4 mm ∅∅∅∅ Highly resistant against passive inflammability. Threaded stud M12 at the bottom for easy mounting and
grounding. M5 screw terminal
• Any mounting position
• Hermetically sealed casings Protection against moisture and oxidation. LONG-TERM capacitance stability.
Design of ESTA L.V. Tubular Can Type Capacitors
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 22
Vishay ESTA
• “Stacked” assembly of the winding elements Neighboring contact areas of winding elements are
connected with the same line terminal. No risk of high energy short circuits between line
terminals. Same proper contact area for each winding
element to solder connections to the terminal.
• Internal connection, outside the winding elements Low thermal resistance to the capacitor’s surface. No heat concentration in the winding cores.
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 23
Vishay ESTA
A =π⋅π⋅π⋅π⋅(r - r )32
3 22
A =π⋅π⋅π⋅π⋅( r - r )22
2 12
Comparison between theESTA stacked assembly and “concentric” competitor design
Insulation between the windings
A =π⋅π⋅π⋅π⋅r2
1 1r1
r2
r3
r1
all contact areas of
same large size
smallest contact
area
A ≠≠≠≠1 A ≠≠≠≠ A32
Advantagefor the
stacked
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 24
Vishay ESTA
Two different diameters are available
• 64 mm diameter with double push-on connectors.
• 84 mm diameter with M5 screw-on terminal.
These small can diameters ensure excellent heat transfer to reduce inner temperature and to increase life expectancy of the capacitors.
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 25
Vishay ESTA
Additional Advantage of the 84 mm cans
• Cable cross sections up to 25 mm².
• Overcurrent up to 50 A (84.4 mm diameter, oil-filled version, at maximum 65°C casing temperature)
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 26
Vishay ESTA
Two different versions are available:
• Oil-filled ESTAprop PhMKP
• Dry version ESTAdry PhMKPg
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 27
Vishay ESTA
All oil-filled part types can also be produced in a PhMKPg dry version.
Dimensions and ratings are unchanged.
Dry types are not standard stock items, with production upon request.
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 28
Vishay ESTA
ESTAprop
MKP-tubular can type capacitors are filled with a specially treated oil:
• Highly fire-resisting: flash point 285°C,ignition point 315°C
and ...
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 29
Vishay ESTA
There are no legal regulations regarding its destruction. The oil can be safely disposed of along with ordinary refuse.
• NON-toxic
• NON-PCB
• Vegetable, natural base (castor oil)
• Fully biodegradable
• Environmental friendly
ESTAprop
field of rape-seed
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 30
Vishay ESTA
ESTAdry
MKP-tubular can type capacitors are filled with an inert gas:
• Environmental friendly
• NON-toxic
• NON-PCB
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 31
Vishay ESTA
Both versions, ESTAprop and ESTAdry comply with
The highest temperature class D (max. value of ambient temperature = 55°C),as specified by the standards.
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 32
Vishay ESTA
Its low thermal resistance provides excellent heat dissipation,which helps to overcome very high loads.
For comparison: thermal conductivity of
castor oil: approx. 0.18 W/(m·K)
gas: approx. 0.026 W/(m·K)
We recommend the use of our oil-filled standard version, especially for filter applications:
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 33
Vishay ESTA
Terminal of the 64 mm diameter casing:Double push-on connectors.
Benefit of the double connectors:
• One connection forthe supply.
• One connection for the discharge resistor.
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 34
Vishay ESTA
• Individual connection of each capacitor Single connection up to 25mm² cable cross section
• IN-LINE connectionbetween two capacitors of 84mm diameter.(„FEED-THROUGH terminal“)
Terminal of the 84mm type
• M5 screw-on terminal
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 35
Vishay ESTA
A flat „thickfilm“ discharge resistor unit is prefitted to our standard capacitor types of 84 mm diameter.
Benefits:
• Connection screws are not covered by the discharge resistor unit.
• Easy mounting andconnection to the supply byforked terminals onto the prefitted screws.
Discharging to 50V or less within 1 minute.
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 36
Vishay ESTA
IP20 protective covers prevent unintentional touching of live terminals
Proper ventilation by side slots and additional holes in thecover‘s top.
Accessory
64mm
84mm
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 37
Vishay ESTA
Type No., correspondingto the article No.
Lot or (Batch) No.
Jointed Flange Connection(in German: „Bördelrand“)
Crimping or Expansion Gap(in German: „Sicke“)
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 38
Vishay ESTA
Installation, Operating and Maintenance
Instructions
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 39
Vishay ESTA
Easy connection by prefitted screws & discharge resistor:
1) to loosen each of the 3 screws a little.
2) to come in
1
3) to fasten each of the 3 screws again.
4) Ready.
31
3
(and feed through)with forked connectors.
2 22
2
2 22
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 40
Vishay ESTA
Definition of ratings:
Ucn, rated voltage: the r.m.s. value of the alternating voltage ...
In, rated current: the r.m.s. value of the alternating current ...
Cn, rated capacitance: the capacitance value ...
... for which the capacitor has been designed.
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 41
Vishay ESTA
A) Maximum permissible current
ESTAprop MKP-type capacitors are suitable for continuous operation at an r.m.s. line current of 1.3 times the fundamentalcurrent that occurs at rated sinusoidal voltage and rated frequency, excluding transients. Taking into account the capacitance tolerances of 1.15 · Cn, the maximum current can reach 1.5 · In.These overcurrent factors are intended to take into account the combined effects of harmonics, overvoltages and capacitance tolerance.
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 42
Vishay ESTA
B) Maximum permissible voltage
ESTAprop MKP-type capacitors are suitable for operation at voltage levels as indicated in the table (extract of IEC 60831 - 1 clause 20 - Table 3) below:
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 43
Vishay ESTAMaximum permissible voltageFrequency Voltage
factor · Ucnr.m.s.
Maximumduration
Observation
Power frequency
1.0 Continous Highest average value during any period of capacitor energization.
Power frequency
1.10 8 hours in every
24 hours
System voltage regulation and fluctuations
Power Frequency
1.15 30 minutes in every 24
hours
System voltage regulation and fluctuations
Power Frequency
1.20 5 minutes Voltage rise at light load
Power Frequency
1.30 1 minute
Power Frequency
+ Harmonics
Such that the current does not exceed the value given above.
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 44
Vishay ESTA
Maximum permissible voltage
The amplitude of the overvoltages that may be tolerated without significant deterioration of the capacitor depends on their duration, the number of applications, and the capacitor temperature. It is assumed that the overvoltages given in table 3 and having a value higher than 1.15 · Ucn occur 200 times in the life of the capacitor.
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 45
Vishay ESTA
C) Harmonic distortionCapacitors can be overloaded in networks distorted by harmonics. This situation is even more critical in case of resonance. In case of resonance the capacitor current or voltage can be a few times as high as the nominal voltage. Therefore, special precautions (e.g. series filter circuit reactors) should be taken in networks distorted by harmonics. Vishay ESTA's warranty only applies for operating conditions in accordance with the above mentioned standards.
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 46
Vishay ESTA
D) Damping of inrush current
Switching devices especially suited for capacitor switching shall be used. For example, the device shall be such that restriking during breaking operations, which may result in high overvoltages, cannot occur.
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 47
Vishay ESTA
Damping of inrush current
High output densities and reduction of losses have resulted in reduced resistance of modern MKP-type capacitors. Especially switching capacitors in parallel to others being already energized, cause very high inrush currents which
should be reduced to ≤≤≤≤ 100 x In. As a consequence, the life cycle of contactors and also capacitors will be affected. In case of detuned capacitor banks the inrush current will partially be limited by the inductivity of the series filter reactors.
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 48
Vishay ESTA
Damping of inrush currentFor capacitor banks without filter reactors, it is strongly recommend to use capacitor contactors with series resistors.Vishay ESTA recommends these special contactors instead of damping the inrush current by coiling up the connection cable between contactor and capacitor. This is due to superior damping behavior and reduced losses in connecting cables, resulting in temperature reduction inside the cubicle.
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 49
Vishay ESTA
Damping of inrush current
The capacitor contactors will have to be replaced after about 100,000 switching operations. Modern PFC controllers are able to memorize the switching number per capacitor step.
A regular check of the contactors is strongly recommended. Detailed information on this will be given by the contactor supplier.
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 50
Vishay ESTA
E) Operating temperaturesCapacitors are classified for ambient temperature categories, each category being specified by a number followed by a letter. The number represents the lowest ambient-air temperature at which the capacitor may be operated.The letters represent upper limit of operating temperature, having maximum values specified in the table below.ESTA PhMKP and PhMKDg -types, CAPACITORS IN ALUMINIUM CASING are designed for category: -25 / D. Maximum average ambient temperature over 1 year: 35°C.
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 51
Vishay ESTA
Operating temperatures
Ambient temperature °C
Maximum Average over
Maximum 24 hours 1 year
A 40 30 20
B 45 35 25
C 50 40 30
D 55 45 35
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 52
Vishay ESTA
Operating temperatures
A measure for life expectancy of the capacitor is also the max. permitted casing temperature, not to exceed 65°C(measured on top of the can). For this temperature indicators may be used, placing on the capacitors, about 3cm below their top.
Such self-adhesive strips will last for about 6 months before expiration. Then they have to be replaced.
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 53
Vishay ESTA
Supplied types: Ratings, Terminals,
Torques, Discharging
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 54
Vishay ESTA
Terminal screw-terminal M5 for max. 25mm²single cable cross section
Tightening torque of M5 terminal screws
2 Nm
Tightening torque of M12 mounting stud
10 Nm
Discharge resistor≤≤≤≤ 50V within 60 sec
3 x 360kΩ (Delta), IP00Thickfilm technology PR = 690² / 360k = PR = 1.32 W/Phase
Capacitor UL/ULc approved
Article NO. Capacitancedelta
connection
Dimensions
∅∅∅∅ * H mm
Weightkg
5343-44522-02 3 * 55.8 µµµµF 84.4 * 340 1.9
ESTAdry PhMKPg660.3.22,90
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 55
Vishay ESTA
ESTAdry PhMKPg660.3.22,90
Un 50 Hz 60 Hz
660 V 22,90 kvar 27,48 kvar
600 V 18,90 kvar 22,70 kvar
690 V 25,00 kvar 30,00 kvar
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 56
Vishay ESTA
How to measure the decrease in capacitance?
3UQ
In ⋅⋅⋅⋅
====Y
2n
2n C
3U3CU3Q ⋅⋅
⋅=⋅⋅⋅=
Due to overloading and consequent self-healing processes, there is a decrease of capacitance over the lifetime of the capacitor.
According to IEC 60831-1, the acceptable „minus“-tolerance for units and banks is „-5%“ of the nominal capacitance value. Easy way to measure is by „Clamp-A-meter“, as there is a linear function between output Q, capacitance (no matter, star or delta) and nominal (fundamental) current I:
and
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 57
Vishay ESTA
How to measure the decrease in capacitance?
Un 50 Hzfundamental In
60 Hzfundamental In
660 V 22,90 kvar 20.03A
27,48 kvar 24.04A
600 V 18,90 kvar 18.19
22,70 kvar 21.84A
690 V 25,00 kvar 20.92A
30,00 kvar 25.10A
ESTAdry PhMKPg660.3.22,90
Make sure to measure only the fundamental current and on all three lines separatelly.
All other parameters unchanged, deviation in % in current is the same as in capacitance.
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 58
Vishay ESTA
How to calculate the required
capacitor output for Power Factor Correction
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 59
Vishay ESTA
What is Power Factor?What is Power Factor?
AC power is transmitted with the least losses if the current is undistorted and exactlysynchronized with the voltage. Light bulbs and resistance heaters draw current exactlysynchronized and proportional to voltage, but most other loads tend to draw current with a timelag (i.e. phase shift) or to distort it (i.e. introduce harmonics). It takes more current to deliver afixed amount of power when the current is phase shifted or distorted. The ratio of the actualpower transmitted (“real power”) to the apparent power that could have been transmitted if thesame current were in phase and undistorted is known as the power factor. It is always less than orequal to 1.
Power Factor = Real Power / Apparent power
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 60
Vishay ESTA
Capacitive Reactance / Inductive Reactance Effect Of Power factor Correction
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 61
Vishay ESTA
P
Q1 Q1
Qc
Qc
Q2
ϕϕϕϕ 2
S2
ϕϕϕϕ 1
S1
Required Capacitor Output
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 62
Vishay ESTA
P: real power / W
Q2: reactive power after improvement / kvarS2: apparent power after improvement / kVAϕϕϕϕ2: phase angle of target power factorcos ϕϕϕϕ2: target power factor
Qc: required capacitor output / kvar
Q1: reactive power before improvement / kvarS1: apparent power before improvement / kVAϕϕϕϕ1: phase angle of actual power factorcos ϕϕϕϕ1: actual power factor
Required Capacitor Output
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 63
Vishay ESTA
Out of the gradients:
And: Qc = Q1 - Q2
= tan ϕϕϕϕ1 Q1 = P · tan ϕϕϕϕ1
Q1
P
= tan ϕϕϕϕ2 Q2 = P · tan ϕϕϕϕ2
Q2
P
Qc = P · (tan ϕϕϕϕ1 - tan ϕϕϕϕ2)
Qc = P · (tan (cos-1 (cos ϕϕϕϕ1)) - tan (cos-1 (cos ϕϕϕϕ2)))
= P · k
Required Capacitor Output
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 64
Vishay ESTA
TARGET POWER FACTOR0.70 0.75 0.80 0.85 0.90 0.92 0.94 0.96 0.98 1.00
ActualPower Factor
0,40 1.27 1.41 1.54 1.67 1.81 1.87 1.93 2.00 2.09 2.290,45 0.96 1.10 1.23 1.36 1.50 1.56 1.62 1.69 1.78 1.980.50 0.71 0.85 0.98 1.11 1.25 1.31 1.37 1.44 1.53 1.730,55 0.50 0.64 0.77 0.90 1.03 1.09 1.16 1.23 1.32 1.520,60 0.31 0.45 0.58 0.71 0.85 0.91 0.97 1.04 1.13 1.330,65 0.15 0.29 0.42 0.55 0.68 0.74 0.81 0.88 0.97 1.170,70 0.00 0.14 0.27 0.40 0.54 0.59 0.66 0.73 0.82 1.02
0.75 0.00 0.13 0.26 0.40 0.46 0.52 0.59 0.68 0.880,80 0.00 0.13 0.27 0.32 0.39 0.46 0.55 0.750.85 0.00 0.14 0.19 0.26 0.33 0.42 0.620,90 0.00 0.06 0.12 0.19 0.28 0.48
Qc = P · k
Values for k:
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 65
Vishay ESTA
TARGET POWER FACTOR0.70 0.75 0.80 0.85 0.90 0.92 0.94 0.96 0.98 1.00
ActualPower Factor
0,40 1.27 1.41 1.54 1.67 1.81 1.87 1.93 2.00 2.09 2.290,45 0.96 1.10 1.23 1.36 1.50 1.56 1.62 1.69 1.78 1.980.50 0.71 0.85 0.98 1.11 1.25 1.31 1.37 1.44 1.53 1.730,55 0.50 0.64 0.77 0.90 1.03 1.09 1.16 1.23 1.32 1.520,60 0.31 0.45 0.58 0.71 0.85 0.91 0.97 1.04 1.13 1.330,65 0.15 0.29 0.42 0.55 0.68 0.74 0.81 0.88 0.97 1.170,70 0.00 0.14 0.27 0.40 0.54 0.59 0.66 0.73 0.82 1.02
0.75 0.00 0.13 0.26 0.40 0.46 0.52 0.59 0.68 0.880,80 0.00 0.13 0.27 0.32 0.39 0.46 0.55 0.750.85 0.00 0.14 0.19 0.26 0.33 0.42 0.620,90 0.00 0.06 0.12 0.19 0.28 0.48
The required capacitor output (Qc)may be calculated as follows:
• select the factor k(matching point of actual and target power factor)• calculate the required capacitor rating with the formula: Qc = k * P
Example: actual power factor = 0.70target power factor = 0.96real power P = 35 kW capacitor output Qc = ?
Qc = k * P = 0.73 * 35 kW = 25.5 kVAr
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 66
Vishay ESTA
Example:
A) actual cos ϕϕϕϕ1 = 0.84, target cos ϕϕϕϕ2 = 0.95
How close should one come to cos ϕϕϕϕ = 1 („Unity“)?
Qc ≈≈≈≈ 0.3173 ·P
B) actual cos ϕϕϕϕ1 = 0.95, target cos ϕϕϕϕ2 = 1.00
Qc ≈≈≈≈ 0.3287 ·P
Step B requires in addition approx. the same capacitor output as step A!
Economical Power Factor Improvement
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 67
Vishay ESTA
Output, Capacitance
& Current of
Capacitors
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 68
Vishay ESTA
Output/Reactive Power of a Capacitor:Output/Reactive Power of a Capacitor:
In general: Active Power P = U · IactiveIn general: Active Power P = U · Iactive
Voltage U and Current I are r.m.s. values.Voltage U and Current I are r.m.s. values.
valuepeak:U;2
UU ˆˆ
= valuepeak:I;2II ˆˆ
=
In sinusoidal conditions: In sinusoidal conditions:
same definition: Reactive Power Q = U · Ireactivesame definition: Reactive Power Q = U · Ireactive
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 69
Vishay ESTA
Output of a 3-phase CapacitorOutput of a 3-phase Capacitor
Three times the output per phase:
Q = U · I Q = U² · ωωωωC (Ohmic Law)
Three times the output per phase:
Q = U · I Q = U² · ωωωωC (Ohmic Law)
Voltage U (between phase/neutral):Voltage U (between phase/neutral):
phases.betweenvoltage:U;3
UU nn=
Y
2n C3
U3Q ⋅⋅
⋅= Y
2n C
3U3 ⋅⋅⋅= Y
2n CU ⋅⋅=
UUn
CY
„Star“-Connection
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 70
Vishay ESTA
Output of a 3-phase CapacitorOutput of a 3-phase Capacitor
Y
2n
2n C
3U3CU3Q ⋅⋅
⋅=⋅⋅⋅=
„Delta“-Connection
Un
Un
C∆∆∆∆
(((( ))))2
n CU3Q ⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅====
3CC Y
=
or:
If Output is the same:
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 71
Vishay ESTA
Capacitance & Current of
Capacitors
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 72
Vishay ESTA
Measured Capacitance
does not depend on
DELTA or STAR connection
Measured Capacitance
does not depend on
DELTA or STAR connection
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 73
Vishay ESTA
Measured Capacitance on STAR connection:Measured Capacitance on STAR connection:
C-meter
CY
Ymeasured C21
C ⋅=
CY
„Star“-Connection
C-meter
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 74
Vishay ESTA
Measured Capacitance on DELTA connection:Measured Capacitance on DELTA connection:
„Delta“-Connection
C∆∆∆∆
measured C23
C ⋅=
C-meter C-meter
C∆∆∆∆
Ymeasured C21
C ⋅=3
CC Y
=
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 75
Vishay ESTA
For both:For both:„Delta“-Connection
C∆∆∆∆
C-meter
Ymeasured C21
C ⋅=
As a Result:As a Result:
CY
„Star“-Connection
C-meter
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 76
Vishay ESTAMeasured Capacitance on DELTA connectiontwo terminals short-circuited:Measured Capacitance on DELTA connectiontwo terminals short-circuited:
„Delta“-Connection
C∆∆∆∆
measured C2C ⋅=
C-meter
Ymeasured C32
C ⋅=3
CC Y
=
C-meter
C∆∆∆∆
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 77
Vishay ESTA
Measured Capacitance on STAR connectiontwo terminals short-circuited:Measured Capacitance on STAR connectiontwo terminals short-circuited:
Ymeasured C32
C ⋅=
CY
„Star“-Connection
C-meter C-meter
CY
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 78
Vishay ESTA
For both:For both:
As a Result:As a Result:
„Delta“-Connection
C∆∆∆∆
C-meter
„Star“-Connection
Ymeasured C32
C ⋅=
CY
C-meter
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 79
Vishay ESTA
Discharge Resistor Value
does not depend on
DELTA or STAR connection of the capacitor
Discharge Resistor Value
does not depend on
DELTA or STAR connection of the capacitor
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 80
Vishay ESTA
Discharge Resistor Value does not depend on DELTA or STAR
connection of the capacitor
Discharge Resistor Value does not depend on DELTA or STAR
connection of the capacitor
R
Cn
R
Cn
n CC =n
Yn
CC31
C3CC
=⋅
⋅==
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 81
Vishay ESTA
As shown for the capacitance measurement and the discharge resistor value, there is
no reason to insist on either a star or
a delta connection of the capacitor.
Both connections are equal in result.
The capacitor is just a black box, providing the same output while operating on same
voltage and frequency.
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 82
Vishay ESTA
Capacitor output (KVAr) changes w.r.t change in voltage and / or frequency .
Capacitor output (KVAr) changes w.r.t change in voltage and / or frequency .
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 83
Vishay ESTA
Capacitor output (KVAr) in case of voltage and / or frequency different to the rated values :Capacitor output (KVAr) in case of voltage and / or frequency different to the rated values :
Note Unew < UcnNote Unew < Ucn
Ucn = rated capacitor voltage (V)fcn = rated capacitor frequency (Hz)Qcn = rated capacitor output (KVAr) at Ucn and fcn
Unew = New Supply voltage applied on the capacitorfnew = New frequency applied on the capacitorQnew = New Capacitor output at Unew and fnew
Ucn = rated capacitor voltage (V)fcn = rated capacitor frequency (Hz)Qcn = rated capacitor output (KVAr) at Ucn and fcn
Unew = New Supply voltage applied on the capacitorfnew = New frequency applied on the capacitorQnew = New Capacitor output at Unew and fnew
(Never Apply more than rated voltage to the Capacitor)
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 84
Vishay ESTA
Capacitor output (KVAr) in case of voltage and / or frequency different to the rated values :Capacitor output (KVAr) in case of voltage and / or frequency different to the rated values :
Ycn2cn Cf2UQ ⋅⋅⋅⋅= ) f2 ( ⋅⋅=
Ynew2newnew Cf2UQ ⋅⋅⋅⋅=
cn2cn
cn
new2new
newY
f2UQ
f2UQC
⋅⋅⋅=
⋅⋅⋅=
cncn
2cn
new2new
new Qf2Uf2UQ ⋅
⋅⋅⋅⋅⋅⋅= cn
cn
new2
cn
new Qf
fU
U ⋅⋅
=
The capacitance CY (uF) of the capacitor is a physical value & will remain unchanged,
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 85
Vishay ESTA
Capacitor output (KVAr) in case of voltage and / or frequency different to the rated values :Capacitor output (KVAr) in case of voltage and / or frequency different to the rated values :
cncncn
new2
cn
newnew Q
5060Q
ff
UUQ ⋅=⋅⋅
=
For example:
60Hz instead of 50Hz
20% increase of the capacitor output and the current.An additional thermal load must be taken into account.
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 86
Vishay ESTA
Phase-Current of a 3-phase capacitor:Phase-Current of a 3-phase capacitor:
Remember:Three times the output per phase:
Q = 3 · U · I
Remember:Three times the output per phase:
Q = 3 · U · I
I3
U3Q n ⋅⋅=
UUn
CY
„Star“-Connection
I
3UQI
n ⋅=
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 87
Vishay ESTA
Life expectancy of Power Factor Correction
Capacitors
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 88
Vishay ESTA
Statistical life expectancy in operating hours:
The Rated Specs of Life Are
≥≥≥≥ 150 000 (ESTAprop)≥≥≥≥ 130 000 (ESTAdry)
At Rated Temp (65 deg C) & at Rated Un / fn
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 89
Vishay ESTA
Statistical life expectancy in operating hours:
Note: service life of a capacitor strongly depends on the operating (i.e. casing) temperature.
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 90
Vishay ESTA
Measures to extend the Service Life:
• Capacitor design (capacitor supplier)- proper design, e.g. on slim diameters, providing
excellent heat dissipation etc.
• Capacitor bank design (switch-board manufacturer)- sufficient cooling- usage of special capacitor contactors etc.
• Environmental conditions (user)- maintenance in general, - replacement of contactors in time etc.
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 91
Vishay ESTA
Mean-Time-Between-Failure (MTBF)of Vishay ESTA Low Voltage tubular capacitors, series PhMKP/PhMKPg is 30,000,000 hours *
*) based on statistical evaluations on production numbers, returns and information from customer's side on failures without returns during the time interval of January 1998 till August 2003.
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 92
Vishay ESTA
• VDE 0560, part 46+47 (German)
• EN 60831, part 1+2 (European)
• IEC 60831, part 1+2 (International)
Standards of
Low Voltage Capacitors
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 93
Vishay ESTA
Thank You For Your Kind Attention !
20 January 2005 Vishay ESTA - Low Voltage Capacitors - Training for Suzlon 94
Vishay ESTA
For further questions please contact:
Vishay Electronic GmbHDivision ESTAP.O. Box 588
D-84003 Landshut, Germany
www.vishay.com/brands/esta/main.html
Low Voltage DepartmentPhone: + 49 - 8 71- 86 25 79
Fax: + 49 - 8 71- 86 25 12e-mail:[email protected]