SPWG SHORT CIRCUIT CASE BUILDINGAND DEVELOPMENT - 2014

July 17, 2014

Qiuli Yu and Jay Teixeira

ERCOT

2

Topics

•Case Building Process for Current Year and Future Year Cases

o Current Year Case Process

o Future Year Case Process

o Software Requirement/Update

•Case Development and Achievement in 2014

o Generator Synchronization with SSWG

o Sequence Impedance

o Grounding Impedance

o Voltage Profile

o Current Limit

• Wind Farm Modeling—WTG Equivalent Circuit

Jul 17, 2014

3

Case Building Process – Current Year

• Time Span

o From Mid-December (Previous Year) to Mid-April (Current Year)

o Total 6 Passes – Pass 0, 1-4, and Final Pass

o Two Weeks for TSP to Submit Change Files

o One Week for ERCOT to Develop Short Circuit Model

• Base Case

o Future Year Final Pass created last year

o Example: 2015 CY base case = SPWG_2015_FY_UPDATED_07032014_FINAL

July 17, 2014

4

Case Building Process – Future Year

• Time Span

o From Mid-April (Current Year) to Mid-July (Current Year)

o Total 6 Passes – Pass 0,1-4, and Final Pass

o One Week for TSP to Submit Change Files

o One Week for ERCOT to Develop Short Circuit Model

• Base Case

o Current Year Final Pass created in current year

o Example: 2016 FY base case = SPWG_2015_CY_UPDATED_04xx2015_FINAL

July 17, 2014

5

Summary – Base Cases for CY and FY

This Year’s Base Case

Base Case to be Used for Creating the New Base CaseWhen the Base Case is Created

2015_CY SPWG_2015_FY_Updated_07032014_Final.DXT Last Year (2014)

2016_FY SPWG_2015_CY_Updated_xxxx2015_Final.DXT This Year (2015)

2017_FY SPWG_2015_CY_Updated_xxxx2015_Final.DXT This Year (2015)

2018_FY SPWG_2015_CY_Updated_xxxx2015_Final.DXT This Year (2015)

2019_FY SPWG_2015_CY_Updated_xxxx2015_Final.DXT This Year (2015)

2020_FY SPWG_2015_CY_Updated_xxxx2015_Final.DXT This Year (2015)

July 17, 2014

6

Summary – Change Files for 2016-2020 FY Cases

2015 FY 2016 FY

2016 CHF

2015 FY 2017 FY

2017 CHF

2015 FY 2018 FY

2018 CHF

2015 FY 2019 FY

2019 CHF

2015 CY

2016 CHF

2016 FY

2015 CY

2017 CHF

2017 FY

Cases Built Last Year

July 17, 2014

7

Software Requirement and update

• ERCOT and TSPs:o PSSE v33o ASPEN OneLiner V12.4

• ERCOT:o RARF Databaseo MODFileBuilder v33

July 17, 2014

8

Case Development and Achievement in 2014

• Add generators to synchronize with SSWG caseso Grandview, PH1, PH2, WindThorst, Stephens Ranch, Spinning

Spur Wind 3, Long Horn, RenTech Project, Hereford,……o Most new gens are wind farmso Some gens with incomplete RARF data have not been modeled

• Sequence Impedance Data (P.U.)o Come from RARF submitted by REs o Some verification rules:

X”<X’<X

R0 &X0 may be 99999 for WTG

o Process: Query out from RARF database and manually copy/paste to PSSE file

Jul 17, 2014

Direct Axis Subtransient Reactance (Saturated) X"Direct Axis Transient Reactance (Saturated) X'Positive Sequence resistance R1

Positive Sequence reactance X1

Negative Sequence resistance R2

Negative Sequence reactance X2

Zero Sequence resistance R0

Zero Sequence reactance X0

9

Case Development and Achievement in 2014 (continue…)

July 17, 2014

10

Case Development and Achievement in 2014 (continue…)

• Voltage Profileo Voltage profile is the Vsched (pu) in the Machine Tab in

PSSE

o Come from SSWG base case (PSSE raw file)o Process: Manually copy from SSWG base case and paste into SPWG PSSE file

July 17, 2014

Bus Number Bus Name Id Area Num Area Name Code VSched (pu)1007 AAAA 1 1 XXXX 4 11031 BBBB 1 1 XXXX 4 11035 CCCC 1 1 XXXX 4 11036 DDDD 1 1 XXXX 4 11037 EEEE 1 1 XXXX 4 11038 FFFF 1 1 XXXX 1 11349 GGGG 1 901 YYYY 2 1.0141863 HHHH 1 1 XXXX 4 16034 IIII F 6 ZZZZ 2 1.0256103 JJJJ EQ 14 QQQQ 3 1.0457018 KKKK N2 7 RRRR 2 1

11

Case Development and Achievement in 2014 (continue…)

July 17, 2014

12

Wind Farm Modeling—WTG at Different kV

• Currently WTG are modeled at different kV levels in SPWG:

o 0.575 kV

o 0.690 kV

o 34.5 kV

July 17, 2014

IND PK D69.kV 940

BUFF_G_UNIT134.5kV 180451

BUFF_G_UNIT334.5kV 180453

BUFF_GAP_2_8138.kV 180455

BUFGGEN0A13.8kV 60092

IND PK D69.kV 940

BUFF_G_UNIT134.5kV 180451

BUFF_G_UNIT334.5kV 180453

BUFF_GAP_2_8138.kV 180455

BUFGGEN0A13.8kV 60092

13

Wind Farm Modeling—WTG Equivalent Circuit (Future Work)

• Equivalent Circuit and Parameters (One Feeder):

• Individual WTG will be aggregated per feeders• Topology and Parameters – RARF• Hope to complete December of 2014, depending on RARF data

submission

July 17, 2014

14

Possible Methods for WTG Equivalent Circuit Development

• Method 1 – Fault Current Simulation Using PowerWorld

July 17, 2014

Fault Current Magnitude: 1.468 p.u.Fault Current Angle: -88.98 degrees

15

Possible Methods for WTG Equivalent Circuit Development

• Method 2 – Equivalent impedance calculation based on Wind Farm topology and collector system parameters

July 17, 2014

16

Possible Methods for WTG Equivalent Circuit Development

• Method 3 – Use equivalent network function in PSSE/PowerWorld?

• Any Comments?

July 17, 2014

17

Questions

July 17, 2014