This document provides an overview of the UWIG (Modeling & Interconnection User Group) evolution and focus, including: - UWIG was established in the early 1990s and has expanded its focus over time due to industry growth. - UWIG's current objectives are to identify urgent modeling and interconnection issues and make contributions to address these issues through member resources and coordination with other groups. - An example UWIG project timeline is provided showing development of wind turbine models over 24 months.

1. Overview of UWIG
Modeling & Interconnection User Group
Wind Generation in Power Systems: A Short Course on the Integration and
Interconnection of Wind Power Plants into Electric Power Systems
September 21-24, 2010
Sheraton Austin at the Capitol
Austin, TX
Robert M. Zavadil
Vice-President & Principal Consultant
620 Mabry Hood Road, Suite 300
Knoxville, Tennessee 37932
Tel: (865) 218-4600 ext. 6149
bobz@enernex.com
www.enernex.com
UWIG Evolution
 Established in early 1990’s
 Provided forum for exchange of information about wind
generation – utility focus
 Explosive growth of wind industry in later 1990’s
necessitated some modification to focus and objectives
 Users groups established to provide way for more specific
and detailed discussion of individual topics in industry
UWIG Short Course on the September 21‐24, 2010
Integration and Interconnection of Wind Power Plants into Electric Power Systems Slide 2

2. Modeling and Interconnection Users Group ‐
Focus and Objectives
 Identify most urgent needs related to wind plant modeling and
interconnection studies
 Determine where and how UWIG can make a contribution
– Direct contributions by UG (volunteer) resources
– Coordination with NREL technical resources
– Develop draft work scopes for larger questions; suggest ideas for funding
 Initiate specific activities to address questions with reach of UG
resources
 Collect, assimilate, and disseminate information from sources
outside the group
UWIG Short Course on the September 21‐24, 2010
Integration and Interconnection of Wind Power Plants into Electric Power Systems Slide 3
Time from
Milestone or Task Completion
Project Start
UWIG Wind Turbine Model Development Initiative
UWIG Project Kickoff Meeting and TRC #1; Cedar Rapids, IA 1 month
Application Guide Draft Outline
Recommended extensions to existing generic models
Construct benchmark test system(s)
Complete inventory of commercial wind turbine model documentation
TRC #2 Teleconference: 4 months
Perform parametric simulations for generic models on benchmark system(s)
Inventory available field data, test stand data, or detailed transient simulations
Devise program for collection of field data from archives, ongoing activities (e.g. NREL),
or new field measurements
UWIG Project Review Meeting and TRC #3; Portland, OR 7 months
Perform simulations on benchmark systems with commercial wind turbine models
Adapt generic model parameters to best fit commercial model behavior
TRC #4 Teleconference 10 months
Develop material for application guide and workshops
2 Regional Workshops; Dallas, TX and Minneapolis, MN 11 months
2 Regional Workshops; Columbus, OH and Salt Lake City, UT 12 months
UWIG Project Review Meeting and TRC #5; Boston, MA: 13 months
Develop draft application and users guide
TRC #6 Teleconference 16 months
Perform comparative simulations of generic, vendor‐specific, and other available
models for events with available data
UWIG Project Review Meeting and TRC #7; Bakersfield, CA 19 months
TRC #8 Teleconference 22 months
Test generic models in large system case studies
Complete assessment of wind plant modeling techniques
Develop addendum for application guide
Complete web site with project deliverables
Project Completion 24 months

3. This morning’s agenda
 Tools for “volts and vars” analysis
 Bulk system analysis
– PSS/E
– PSLF
 Transient Analysis
– PSCAD
– EMTP‐RV
– PowerFactory/digSilent
UWIG Short Course on the September 21‐24, 2010
Integration and Interconnection of Wind Power Plants into Electric Power Systems Slide 5
Model Hierarchy
 Bulk System Analysis ‐ Generic
Increasing fidelity and complexity
Increasing availability, ease of use
– Power flow
– Short‐circuit
– Positive sequence dynamic
 Bulk System Analysis – vendor or
equipment specific
 Transient Application Models, Generic
 Transient Application Models, vendor
or equipment specific
 Transient – Design Models
UWIG Short Course on the September 21‐24, 2010
Integration and Interconnection of Wind Power Plants into Electric Power Systems Slide 6

4. Popular Transient Simulation Programs
 EMTP‐RV (www.emtp.com)
 PSCAD (http://pscad.com)
 PowerFactory (www.digsilent.de)
UWIG Short Course on the September 21‐24, 2010
Integration and Interconnection of Wind Power Plants into Electric Power Systems Slide 7
Example Applications
for Wind Energy Studies
 Turbine modeling
– Transient models often used as analytical “benchmarks” for
reduced order models (e.g. PSS/E, PSLF)
– Design of challenging interconnections may require some
detailed simulation studies
 Harmonic studies
 General transient studies
– Capacitor switching
– Short‐circuit
– TOV
UWIG Short Course on the September 21‐24, 2010
Integration and Interconnection of Wind Power Plants into Electric Power Systems Slide 8

5. Type I Detailed Model
Vsrms
3 Phase
3 Phase
RMS
RMS
1.01
0
W MAIN
Te Wpu
1.0 [MVA] 1 [MVA]
34.5 [kV] / 0.600 [kV] 115 [kV] / 34.5 [kV]
Multimass
( IndM/c)
IM #2 #1 COUPLED #2 #1
Te I1
RRL
MAIN Vg V1 PI
TL SECTION
TL
ABC->G
Lf
Lf +
Lf +
0.29 [MVAR] 0.05 [MW]
B
A
Power
+
N TL
N/D
Tw TL
Q
P
542057.0 D Timed 1.0e-010
Q1 P1 Lf
Fault
Logic
Pref ABC
1000.0
Pitch Control
* Pact
Pin -1000. beta Timed
& Fault
wref theta Logic
1840.0
Actuator
* wg
wg 1800.0 V_turb
Vterm z wrot Aerodynamic
V_wind Twind
Vsrms *
Wind Source Torque
x vw -1.0 Tw
Mean wind_sp
Vw Cp Calculation
Lambda
vw lambda y Cp
turb_sp Calculation lambda y Rrot
wrot x Rrot
Rrot lamda valid range MWT1000A_Aero.txt
Rrot
UWIG Short Course on the September 21‐24, 2010
Integration and Interconnection of Wind Power Plants into Electric Power Systems Slide 9
UWIG Short Course on the September 21‐24, 2010
Integration and Interconnection of Wind Power Plants into Electric Power Systems Slide 10

6. UWIG Short Course on the September 21‐24, 2010
Integration and Interconnection of Wind Power Plants into Electric Power Systems Slide 11
UWIG Short Course on the September 21‐24, 2010
Integration and Interconnection of Wind Power Plants into Electric Power Systems Slide 12

7. Type III Detailed Model
(with simplification)
Ir A System ain : Graphs
,M
Ir Line Side Ira1 Vrca 0.7 Crow
Ica
Vr Ica Irb1 Vrcb B Compar-
Vr Converter Irc1 Vrcc Vgrms ator
Icb
Ic Icb
Pc
Current
Ic Icc Ir Vr
Q
P
Power
Vc Icc
0.01 [ohm]
Command D D D
Vg
A
B
Rcrow
0.030 [mH] 0.0015 [H]
vlcb vlcc
0.01 [ohm]
V
Rcrow 0.030 [mH]
V
Icc1
+
Iastar Vgrms
Vrms Rcrow
Ica Controller Rcrow 0.030 [mH] 0.0015 [H]
Vcab
Line Side
Iam vlca Ic Icb1
I 0.0015 [H]
Ica1 Vcbc vlca
0.01 [ohm]
Converter vlcb D D D
V
Ibstar Crow Ica1
Icb Vcca
Control vlcc Icrow
Ibm
Icb1
wg Vgrms Rcrow Vcrow
wg Vrms
0.0014 [H]
Iqs Ira Iarcmd
Rotor
Ipcmd Irb Var Ira1
V
Current Rotor Side
Ids Irc Ibrcmd vrca vrca
Iqcmd Controller Vbr Irb1
0.0014 [H]
Converter
Vterm Iar vrcb Ira1 Irb1 Irc1 I1 I2
Vg Ira1 Vcr Irc1 I1
0.0014 [H]
V
Controller
V
Ibr vrcc vrcc vrcb Vsrms 1
3 Phase
3 Phase
0 RMS
Irb1 MAIN
RMS
RMS
90.588 Rq
Gear ratio 2
1.0
W
Te Wpu
2.5 [MVA] 100 [MVA]
34.5 [kV] / 0.690 [kV] 115 [kV] / 34.5 [kV] 3
Multimass
( IndM/c)
IM #2 #1 COUPLED #2 #1
Te I1 I2
47.5 Rrot RRL
Rotor Radius MAIN V1 PI
SECTION
TL
ABC->G V1
Vg
Lf
Lf +
Lf +
0.05 [MW]
B
A
Power
+
N TL 1
N/D RMS
N Tw TL
Q
P
dw1 + +
D N/D wrot 2
1802244.0 D Timed 1.0e-010
F Q1 P1 Lf
D Fault
wrated Rq Logic 3
Tw * theta ABC
Pitch Control
theta Vg
TL Te wrot wg Ipcmd 1
& RMS
wg Ipcmd Timed Vga
Fault
Iqcmd V_turb Logic 2
Actuator Iqcmd wrot Vgb
*
wg 1200.0 V_wind Aerodynamic 3
Twind
Vterm vw * Vgc
Vgrms Torque -1.0 Tw
Ploss
Wind Source x vw Calculation
Mean z
wind_sp
Vw
Lambda Ploss.txt Cp
vw lambda y x y Cp Rrot
turb_sp Calculation lambda Rrot
Aero.txt
wrot
Rrot lamda valid range Ploss.txt P1 + -
D
Rrot F
Pc
Graphs
N
Q1 N/D ArcTan Cos pfm Aero.txt
D
P1
M : Graphs
ain
*
Tm
UWIG Short Course on the September 21‐24, 2010
wg
Integration and Interconnection of Wind Power Plants into Electric Power Systems Slide 13
Rotor Current - A Rotor Current - B Rotor Current - C
4.0
3.0
2.0
1.0
0.0
y
-1.0
-2.0
-3.0
-4.0
Turbine Line Current - RMS Turbine Line Current
4.0
3.0
2.0
1.0
0.0
(kA)
-1.0
-2.0
-3.0
-4.0
Turbine Term Voltage
inal
1.00
0.75
0.50
0.25
y (kV)
0.00
-0.25
-0.50
-0.75
-1.00
39.60 39.80 40.00 40.20 40.40
UWIG Short Course on the September 21‐24, 2010
Integration and Interconnection of Wind Power Plants into Electric Power Systems Slide 14

8. EnerNex Perspective
 All packages are used for wind energy consulting work
 Choice of program dependent on:
– Nature of problem
– Client preference
– Resource availability
 Typical Applications
– Wind plant collector studies: EMTP‐RV or DigSilent
– Turbine model prototyping, validation: PSCAD
– Vendor application model development: PSCAD, EMTP‐RV
» Unbalanced systems
» Control interactions
 Comments on MatLab
UWIG Short Course on the September 21‐24, 2010
Integration and Interconnection of Wind Power Plants into Electric Power Systems Slide 15