Transcript Slide 1
Group Meeting – Pepco Holdings, Inc.
July 17, 2014
Objectives
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
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1. Activities
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
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1. Activities
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
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1. Activities
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
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2. Accomplishments
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 Autoreconfiguration scheme circuits
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3. Roadblocks
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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4. Lessons Learned & Questions
Lessons Learned
Questions for the DOE
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PV Hosting Capacity Analysis
Existing Feeder
Classify circuits in terms of how much PV can
be added without violating operating criteria
Analysis: Phase balance, Cap Placement, Voltage
Regulator Placement & Settings, Check
protection/coordination
Quantify: Improvement cost, Feeder performance impact,
PV hosting impact
Optimized Feeder
Run optimized feeder setup to include:
Voltage Head Room Configuration
Autonomous Control
Central Control
Quantify: Improvement cost, Feeder performance impact,
PV hosting impact
Pilot Feeder Instrumentation
• Existing Monitoring
PV Systems. With
480 V monitors
Pole-Mount
Monitors
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Pilot Feeder Instrumentation
• EPRI Pole Mount voltage and irradiance monitors
installed March 2012
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Pilot Feeder Instrumentation
• To be installed
INSTALL
SCADA
Communications on
Regulator
PV Systems. With
480 V monitors
Pole-Mount
Monitors
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Pilot Feeder
• Voltage Regulation zones
Zone 4
Zone 2
Zone 3
V. Reg.
V. Reg.
V. Reg.
PV
Systems.
Zone 1
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PV Overvoltage at Low Load
• High voltage occurs
at PV systems in
Zone 2 during min
load
128.5
Voltage Plot to PV System #1
Voltage (120 V Base)
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127.5
127
126.5
126
125.5
125
124.5
124
123.5
0
5
10
15
20
25
30
Distance from Substation (1,000 ft)
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Min Load Feeder Profile
129
Voltage Plot by Voltage Regulation Zone
128
PV Site Overvoltage
Voltage (120 V Base)
127
126
125
Zone 1
Zone 2
124
Zone 3
123
Zone 4
122
121
120
0
10
20
30
40
50
60
70
Distance from Substation (1000 ft.)
• PV penetration limited by high voltage during
min load, when voltage profile is relatively flat
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Min Load Feeder Profile
126
Voltage Plot by Voltage Regulation Zone
Voltage (120 V Base)
125
124
Zone 1
123
Zone 2
Zone 3
122
Zone 4
121
• Reducing
voltage in
zone 2 solves
overvoltage
problem
without
creating low
voltage based
on model
predictions
120
0
10
20
30
40
50
60
70
Distance from Substation (1000 ft.)
• SCADA control of regulator allows for manual
reduction of voltage for demonstration of
concept
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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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Model-Based Simulator
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
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PV Operations Management (FSMA)
FSMA
– Control can be run
against simulator or real
system through
connection to SCADA
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