1
Validation of a Second Generation Type 3
Generic Wind Model
Matthew P. Richwine (Presenter)
matthew.richwine@ge.com
Juan J. Sanchez-Gasca
Nicholas W. Miller
July 30th, 2014
IEEE PES GM
Washington DC
2
Introduction
• GE in active in development of dynamic models
• Use for modeling dynamics of the bulk power system
• Always evolving, trade-offs
Regulated Bus Voltage
Terminal Voltage
Current Command, Ip
Converter
Control
Model
Voltage Command, Eq
Generator /
Converter
Model
Power
Order
Speed
Order
Pitch
Control
Model
GE Type 3 Wind Turbine Model
Shaft Speed
Blade Pitch
Pgen
Qgen
Real & Reactive
Power
Real
Power
Wind
Turbine
Model
First-Generation Type 3 Generic Model
3
Motivation for Testing
Represent installed behavior
Validation checks that models are reasonable
Highlights areas where models can be improved
Emerging Requirements ie. NERC MOD-025,-026,-027
4
Wind Turbine Model
Regulated Bus Voltage
Terminal Voltage
Generic Models v. GE Models
- Both models are similar in that they
neglect the generator flux
- GE models differ in the following
ways:
-
Voltage Droop
Active Power Control (APC)
WindINERTIA
LVRT, ZVRT
Current Command, Ip
Converter
Control
Model
Voltage Command, Eq
-
More input to model development
Pgen
Qgen
Real & Reactive
Power
Power
Order
Speed
Order
Pitch
Control
Model
Shaft Speed
Real
Power
Wind
Turbine
Model
Blade Pitch
First-Generation Generic Model
Vref/Vreg
or Qref/Qgen
Plant Level
Control
Vterm
Pgen
Qgen
fref/freq and
Plant_pref/Pgen
Qref
Changes from first generation to second
generation
- Modularity (7 modules v. 4 modules)
Generator /
Converter
Model
Pgen
Prefo
Pref
Torque
Control
Iqcmd
Electrical
Control
Pgen
Iq
Generator/
Converter
Pord
w
w ref
Ipcmd
Drive-Train
Pm
Pitch
Control
q
Aero
Second-Generation Generic Model
Ip
Model Validation Approach
Equipment
Representation
Model Validation
Actual Equipment
Wind Plant Model
Point of
Interconnection
(POI) Bus
Medium Voltage Bus
(e.g. 34.5kV)
Terminal Bus
P gen
Collector
Equivalent
Impedance
Vreg bus
Substation
Transformer
Q gen
Unit
Transformer
Substation transformers usually have FOA
rating roughly equal to total MVA of WTGs.
Switching shunt reactive compensation at
the substation may be used as a stimulus
for testing
Vterm
Unit transformers are typically
2-3 MVA, 6% leakage reactance
Multiple wind turbines are
delta-wye connected padmounts, modeled as a single
modeled as a single equivalent
equivalent wind turbine
transformer
The collector system may cover several miles, have different
topologies, and is modeled as an equivalent impedance.
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System Model
Physical Wind Farm Schematic
Equivalent Wind Farm Schematic
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Voltage Reference Step Test
Testing can be challenging
• Changing wind conditions
• Changing grid conditions
Voltage Reference Step Test
• Voltage regulation mode
• +2% step at POI (144kV bus)
• Near unit PF prior to step
• Power fluctuating with wind
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Capacitor Bank Switching Test
Shunt Capacitor Switching Test
• Voltage regulation mode
• 10MVAr capacitor switched in,
then out
• Near unit PF at the start of testing
• Power (wind speed) decreasing
10
System
Future Work
POR Bus
Shunt Cap
•
•
•
Capturing power fluctuations in simulation
Frequency response testing
Multi-plant volt/Var coordination
WF1
WF2
WF3
Active coordination
regulates POR
voltage (Red)
Active coordination
balances VARs
from all wind farms
Shunt Capacitor Opens with Active Coordination
applied on top of Droop Coordination
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Conclusions
• Staged testing shows a match among Generic models, GE
models, field test results
• Reactive power path is decoupled from the active power path
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References
[1] A. Ellis, E. Muljadi, J. Sanchez-Gasca, Y. Kazachkov, “Generic Models for Simulation of Wind Power Plants in
Bulk System Planning Studies”, Proc. IEEE Power Engineering Society General Meeting 2011, Detroit, MI,
USA, July 24-28.
[2] A. Ellis, Y. Kazachkov, E. Muljadi, P. Pourbeik, J.J. Sanchez-Gasca , Working Group Joint Report – WECC
Working Group on Dynamic Performance of Wind Power Generation & IEEE Working Group on Dynamic
Performance of Wind Power Generation of the IEEE PES Power Stability Controls Subcommittee of the IEEE
PES Power System Dynamic Performance Committee, “Description and Technical Specifications for Generic
WTG Models – A Status Report”, Proc. IEEE PES 2011 Power Systems Conference and Exposition (PSCE),
March, 2011, Phoenix, AZ.
[3] P. Pourbeik, A. Ellis, J. Sanchez-Gasca, Y. Kazachkov, E. Muljadi, J. Senthil and D. Davies, “Generic Stability
Models for Type 3 & 4 Wind Turbine Generators for WECC”, Proc. IEEE Power Engineering Society General
Meeting 2013, Vancouver, British Columbia, Canada. July 2013.
[4] T. Ackermann, A. Ellis, J. Fortmann, J. Matevosyan, E. Muljadi, R. Piwko, P. Pourbeik, E. Quitmann, P.
Sorensen, H. Urdal, B. Zavadil, “Code Shift – Grid Specifications and Dynamic Wind Turbine Models”, IEEE
Power and Energy, vol. 11, pp. 73-82, Nov./Dec. 2013
[5] E. Muljadi, C.P. Butterfield, A. Ellis, J. Mechenbier, J. Hocheimer, R. Young, N. Miller, R. Delmerico, R.
Zavadil, J.C. Smith, ”Equivalencing the Collector System of a Large Wind Power Plant”, presented at the
IEEE Power Engineering Society, Annual Conference, Montreal, Quebec, June 12-16, 2006.