Group Meeting – Pepco Holdings, Inc.July 17, 2014

2

Use common model and algorithms to:– Make PV analysis a standard part of:

• Planning• Operations Monitoring

– Evaluate impact of PV/DER at feeder and transmission level

Objectives

Topic A1 60 Study Circuits

Build and major validation/correction review complete Measurement collection complete Device setting collection continuing

Completed device setting for Voltage Headroom and DA circuits

Study feeder description Short and stiff, long with high impedance, highly loaded, lightly

loaded, mix of different type customers – residential, industrial, commercial, overhead, underground, feeders with high PV saturation, feeders that are part of a Distribution Automation scheme that can’t currently operate because of a large solar farm, and then a grouping of feeders and substations where high penetration will have an impact on the transmission system.

Remaining work Compare analysis for base case and Voltage Headroom

case

1. Activities

3

1. Activities

4

Topic A2 Voltage headroom circuit selected Utilizing existing monitoring equipment and equipping a

voltage regulator bank with SCADA communications and control

Remaining Year 1 Work Complete Voltage Headroom design and define test procedure

Topic A3 Significant analysis refinement completed

Running testing analysis using study circuits Refining displays and time-series use of measurements and

load data Remaining Year 1 Work

Update and test PV interconnect criteria Compare analysis results for new and old interconnect

criteria

1. Activities

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Topic B4 Have Forecast, Schedule, Monitor and Adjust

(FSMA) Running Conservation Voltage Reduction (CVR) using

capacitors, LTC’s and Voltage Regulators Forecasting operation Comparing against actual results Have method for defining load profile/scenarios

Have control parts of PV complete Adding PV to CVR control functionality Remaining Year 1 Work

Compare base case and controller case performance results

Accomplishments Held on site training and analysis code

feedback with PHI PV Group and Planners Completed model builds and model build

checks for 60 study circuits Collected circuit and load measurements

for analysis Time-series load measurements set for

automated attachment to all circuits Time-series circuit measurements set for

automated attachment to Voltage Headroom and Auto-reconfiguration scheme circuits

2. Accomplishments

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3. Roadblocks

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Model correction and validation

Critical part of making PV analysis a standard part planning and operation management

Taking more time to complete than planned

Breaking up into two parts: Initial model-build, automated

corrections Main work for this is complete. Plan to continue to

refine as this is used over the next 6 months Manual corrections

Need to simplify collection and automated use of corrections made by engineers as a part of running analysis on circuits

This will be the model build focus for the next 6 month

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Lessons Learned Questions for the DOE

4. Lessons Learned & Questions

PV Hosting Capacity Analysis

Existing Feeder

Optimized Feeder

Analysis: Phase balance, Cap Placement, Voltage Regulator Placement & Settings, Check protection/coordination

Quantify: Improvement cost, Feeder performance impact, PV hosting impact

Run optimized feeder setup to include: Voltage Head Room ConfigurationAutonomous ControlCentral Control

Quantify: Improvement cost, Feeder performance impact, PV hosting impact

Classify circuits in terms of how much PV can be added without violating operating criteria

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Pilot Feeder Instrumentation

PV Systems. With 480 V monitors

Pole-Mount Monitors

• Existing Monitoring

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Pilot Feeder Instrumentation

• EPRI Pole Mount voltage and irradiance monitors installed March 2012

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Pilot Feeder Instrumentation

INSTALLSCADA

Communications on Regulator

PV Systems. With 480 V monitors

Pole-Mount Monitors

• To be installed

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Pilot Feeder

V. Reg.

V. Reg.

V. Reg.

Zone 1

Zone 2Zone 3

Zone 4

PV Systems.

• Voltage Regulation zones

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PV Overvoltage at Low Load

• High voltage occurs at PV systems in Zone 2 during min load

0 5 10 15 20 25 30121122123124125126127128129

Voltage Plot to PV System #1

Distance from Substation (1,000 ft)

Volta

ge (1

20 V

Bas

e)

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Min Load Feeder Profile

• PV penetration limited by high voltage during min load, when voltage profile is relatively flat

10 20 30 40 50 60 70120

121

122

123

124

125

126

127

128

129

Voltage Plot by Voltage Regulation Zone

Zone 1Zone 2Zone 3Zone 4

Distance from Substation (1000 ft.)

Volta

ge (1

20 V

Bas

e)

PV Site Overvoltage

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Min Load Feeder Profile

• SCADA control of regulator allows for manual reduction of voltage for demonstration of concept

10 20 30 40 50 60 70120

121

122

123

124

125

126

Voltage Plot by Voltage Regulation Zone

Zone 1Zone 2Zone 3Zone 4

Distance from Substation (1000 ft.)

Volta

ge (1

20 V

Bas

e)

• Reducing voltage in zone 2 solves overvoltage problem without creating low voltage based on model predictions

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PV Operations Management (FSMA)

• FSMA: Forecast, Schedule, Monitor and Adjust– Use for:

• Operations Monitoring• Planning and control simulation

– Currently running coordinated control• LTC’s, voltage regulators and capacitors• Just added PV as controllable devices

• Simulator– Separate copy of Dew that uses same

model used for control, to play the role of the system

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Use simulator to:– See system response

to control, device state and load change

– Test & develop control– Test & develop display

User can set:– Load points/curve– Capacitor states– Voltage regulator states– PV inverter control

FSMA Control– Can be run against

simulator or real system

Model-Based Simulator

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FSMA– Control can be run

against simulator or real system through connection to SCADA

PV Operations Management (FSMA)