IEEE ICC Education SessionOctober 23, 2019

Presenter: Michael Smalley, Principal Engineer, WEC Energy Group

Co Authors: Steven Schott, Ross Barrette, Michael Smalley

SMRP - System Modernization

and Reliability Project

System Information

• 446,000 Electric Customers

• 98% of Electrical System is 24.9 kV

• ASCC: 3,600 Amps, RMS, Sym.

1

Project background

2

SAIDI COMPARISONS

WPS 6-year SAIDI average (336.39)

was higher than the averages

of other state utilities

over the same period

(160.17 minutes)

3

Outage comparisons by territory• 33,167 customers (7.6%)

experienced an average of

5+ outages per year

• 72% of those outages were located

in high density forest areas

• 5,413 customers (1.2%)

experienced an average of

10+ outages per year

• 90% of those outages were located

in high density forest areas

4

Lines to be replaced

• Distribution feeders are radial

• Typical 24.9 KV distribution feeder in rural areas can

run up to 50 circuit miles in one direction

• Advantages

– Fewer substations

– Improved voltage profile

– Fewer losses

• Disadvantages

– Longer radial lines

5

SMRP Phase 1• Optimize performance and cost

• Reliability improvement of 25%

• Move from 3rd/4th quartile to 2nd

quartile

• Add Distribution Automation –

400 miles

• Replace overhead primary

distribution with underground,

focus on areas and feeders

with the worst SAIDI (1000 to

1200 miles over 5 years)

• Total project cost $218 million

• Construction in years 2014

through 2018

6

SMRP Phase 2

• Underground an additional 960 miles

• No distribution automation

• Reliability improvement of 17%

• Project cost $211.5 million

• Construction in years 2018 through 2021

• Yes, we’re in Phase 2 already!

7

PROJECT CYCLE

• Identify and prioritize the overhead

circuits that would provide the

maximum reliability benefit for the

cost investment

• Begin to contact customers and

gauge overall interest in project• Begin Field Design, Collecting

assets, and creation of Construction

Prints

• Environmental Walk-throughs

• General Permitting and Applications• Send out Easement Drawings to

Customers and Begin to Acquire

Necessary Easements• Staking and Construction

• Removal of Existing Overhead

Facilities

• Complete As-Builts and update

GIS

8

Project challenges• Safety

• Customer communications

• Easement obtainment

• No locates for design

• Environmental constraints

• Weather – local and nationwide

• Other facilities in the ground

9

Rock

Availability of skilled workforce

Contractors are performing energization

and cutovers

Quality of installations (PD testing)

Indian reservation construction

9

• Wood turtle

• Bald eagle

• Osprey

• Loggerhead shrike

• Red shouldered hawk

• Little brown bat

• Hine’s emerald dragonfly

• Blanchard’s cricket frog

• Spruce grouse

• Cerulean warbler

• Eastern ribbon snake

• Black tern, Foster’s tern

• Kirtland’s warbler

• Hooded warbler

• Henslow’s sparrow

Threatened and endangered animals encountered

10

Environmental monitoring

11

SMRP safety performance to date• 1,200,000 hours of installation

• 7 OSHA incidents

• 2 Lost Time Incident

• OSHA RIR = 1.19

• Industry avg. RIR = 2.80

12

Installation Techniques• Open Cutting (2%)

• Plowing (50%)

• Vibratory plowing(>75%)

• Plug plowing (<25%)

• Boring (48%)

• Directional

• Pneumatic boring

13

Vibratory Plowing

14

“Plug” Plowing Equipment

15

16

17

18

Typical DA Scheme

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Total

Phase I & II1994 382 434 155 (46%)

SMRP Year Miles URD

Cable

Miles Main

Line

w/DA

Spend

(million $)

Projected

SAIDI

(minutes)

Phase I

2012-2013 - - 6 -

2014 203 48 33 18

2015 229 103 47 19

2016 228 78 56 22

2017 283 99 61 23

2018 151 54 39 10

Phase II

2017 - - 2.5 -

2018 137 - 18 6

2019 274 - 64 26

2020 273 - 64 14

2021 216 - 35 17

2022 - - 2 -

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System Modernization and Reliability Project

• 2014 – 2021 Segments replaced with underground cable (all districts)

• Percent improvement 16% Outage events

34% CMI

11% CI

Actual 2017

Outage Events

Avoided 2017

Outage Events

Actual 2017

Customer

Minutes of

Interruption

(CMI)

Avoided 2017

Customer

Minutes of

Interruption

(CMI)

Actual 2017

Customers

Interrupted (CI)

Avoided 2017

Customers

Interrupted (CI)

8,986 1410 215,148,840 72,000,000 508,521 60,000

21

System Modernization and Reliability Project

• 2014 – 2018 distribution automation schemes (all 13 schemes)

• Percent improvement 0% Outage events

2% CMI

8% CI

Actual 2017

Outage Events

Avoided 2017

Outage Events

Actual 2017

Customer

Minutes of

Interruption

(CMI)

Avoided 2017

Customer

Minutes of

Interruption

(CMI)

Actual 2017

Customers

Interrupted (CI)

Avoided 2017

Customers

Interrupted (CI)

8,986 0 215,148,840 6,000,000 508,521 36,000

22

System Modernization and Reliability Project

• Total SMRP underground installation and distribution

automation

• Percent improvement 16% Outage events

36% CMI

20% CI

23

System Modernization and Reliability Project

24

Additional Estimates for PH I (2014 – 2018)

• 1015 route miles of primary circuit

• 2,533 actual miles of primary

cable

• 80 route miles of secondary

• 128 miles of secondary cable

• 6,400 easements

• 3,680 new underground services

• Warehousing material throughput

doubled for the entire WPS

company

25

SMRP Cable System Materials

• 1 PH Transformers (15, 25, and 50 kVA)• Set on fiberglass box pads

• But flat pads not completely off the table yet

• Formerly included under oil arresters; now using elbow arresters

• Joints• Cold shrink with integral metallic shield and jacket exclusively

• Some push on joints were used in earlier years of PH 1

• Recently converted CS joints to 100% shear bolt connectors

• Terminations• 100% cold shrink silicone rubber terminations

• Separable Connectors• 200 A Loadbreak

• 600 Amp Dead Break having 200 bushings for testing and grounding purposes

• Junction Enclosures - Fiberglass• 200 A and 600 A

26

SMRP Materials - Cable

• Cable Sizes/Designs (all use 100% insulation levels)

• #1 Sol Al (Full Neutral) 25 kV JCN – Most Common Cable used

• #4/0 Strd Al (90% neutral and 1/3rd neutral) 25 kV JCN

• 750 kcmil Al (1/6th Neutral) 25 kV JCN

• Basic cable design as shown below:

• Note: Insulation is mostly TRXLPE, but EPR is also used

27

Solid or Sealed

Conductor

Interesting SMRP Facts

1. Contract installers are certified for installation of cable

accessories prior to working on site.

2. Shunt reactors are sometimes employed on long cable

lengths to control the “Ferranti Effect” due to cable

capacitance

3. When the PSCW approved the project, the use of

unjacketed (bare) concentric neutral cable was allowed

(and used)

• BCN cable is no longer being installed

4. On the application for the CA, the expected life for new

cable was indicated as:

60 years

28

• Some Examples of what we find:

SMRP Materials – New Cable Inspection

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New Cable Inspection Data

30

• Inspecting new cable allows us

to monitor trends in cable

manufacture with time such as:

• Cable Insulation Thickness

• Eccentricity

• Insulation Cure

Project challenges

• Number 1 quality risk identified as

terminations and splices

• Put into place a system to hold

contractors accountable

• Partial discharge (PD) testing for all

personnel doing terminating

• Over 2,000 terminations/splices/ risers

tested

• One cable failure – due to backfill

material, one splice failure

• Contractors initialize each device they

terminate

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PD (partial discharge) testing

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Questions?

•

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