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S P P 2 0 1 4 T P L
D y n a m i c S t a b i l i t y A s s e s s m e n t
December 29, 2014
Engineering Research, Development, and Special Studies
Table of Contents Introduction ..................................................................................................................................................1
Study Scope...................................................................................................................................................1
Fast Fault Screening and Dynamic Assessment ........................................................................1
Dynamic Assessment of Member Specified Events ..................................................................1
Mitigation of Unstable Events ...................................................................................................2
Methodology .................................................................................................................................................2
Fast Fault Screening and Dynamics Analysis ..................................................................................2
Member Specified Events ................................................................................................................3
Results ...........................................................................................................................................................3
Fast Fault Screening (FFS) ..............................................................................................................3
Transient Stability Analysis of Most Severe FFS Events ................................................................4
Transient Stability Analysis of Member Submitted Events .............................................................4
Conclusion ....................................................................................................................................................4
APPENDIX A - Events ................................................................................................................................6
Table 1: NERC Category B, C, & D, Fast Fault Scan Results ................................................................. 6
Table 2: Member Submitted NERC Category B, C, and D Events .......................................................... 9
APPENDIX B - Results ...............................................................................................................................13
Table 3: Unstable Events........................................................................................................................ 13
APPENDIX C – Outaged Branches ...........................................................................................................14
Table 4: NERC Category B, C, & D, FFS Outaged Branches ............................................................... 14
APPENDIX D: Plots and and FFS Data ...................................................................................................22
2014 Stability Study 1
Introduction
The objective of this study is to report findings from the 2014 Stability Compliance Assessment
process to support compliance with NERC TPL-001, TPL-002, TPL-003, and TPL-004 Reliability
Standards for future years 2015 and 2020. This report, along with the Near-Term and Long-Term
Load Flow Assessments, fulfill requirements of applicable TPL Standards.
This report summarizes the potential transient stability violations anticipated by SPP and the
applicable mitigation plans developed by SPP Member Entities and SPP Engineering Staff.
A separate comprehensive report will be issued detailing the 2014 Transmission Planning
Compliance Statement for each TPL Standard. This report will address how each requirement
defined in the TPL Standards is fulfilled by one or more mechanism in the TPL Near-Term or
Longer-Term Compliance Assessments.
Study Scope
Compliance with TPL Standards with respect to system stability requires the following be
completed:
Fast Fault Screening and Dynamic Assessment
Perform a Fast Fault Screening analysis of the SPP Transmission System on the MDWG
2014 Series 2015 Light Load and 2020 Summer Peak Case. Provide a list of potential severe
fault locations, their ranking, and fault sequences for potential category B, C, and D
contingencies.
Perform a transient stability analysis on those FFS screened contingencies with steady state
stability violation, loss of generation, or a computed critical clearing times less than 9 cycles
for both the 2015 and 2020 case.
Dynamic Assessment of Member Specified Events
SPP Members provided SPP Staff with a list, shown in Table 4 of Appendix A, of fifty-six
(56) NERC Category B (Cat. B), Category C (Cat. C) and Category D (Cat. D) reliability
events for transient stability performance analysis. A transient stability analysis was
performed for both the 2015 Light Load and 2020 Summer Peak Cases using these member
submitted events.
2014 Stability Study 2
Mitigation of Unstable Events
Determine mitigation measures for any events found to be unstable that will, by
implementation, provide system stability.
Methodology
Fast Fault Screening and Dynamics Analysis
The Fast Fault Screening (FFS) tool in the POM-TS application screens potential transmission fault
locations for grid stability analysis and quickly identifies the most severe fault locations and ranks
them in the order of severity. The tool begins by identifying the most severe fault locations, above
100kV, which are considered the weaker points in the network. Faults at each of the identified
locations are then ranked according to severity using a Ranking Index (RI) for the loss of one (Cat.
B), two (Cat. C), or multiple (Cat. D) lines, transformers, or generators at each ranked bus. The fault
severity is classified as:
1. Most severe are the faults that lead to steady-state stability violation (e.g., post-fault regime does
not exist);
2. The next level of severity are faults leading to large loss of generation;
3. The rest of the locations are ranked based on the Ranking Index and CCT.
Once the RI is known, the critical clearing time (CCT) is computed. The Critical Clearing Time is
the maximum time during which a disturbance can be applied without generator units losing
transient stability. Details on the methodology are given in [1]. The RI and CCT are used as metrics
to determine fault locations that merit further examination.
Transient stability analysis was performed on ranked contingencies having a steady state stability
violation, a loss of generation, or a critical clearing time of less than 9 cycles using PTI’s PSS/E
Dynamics Package and the PSSPLT Plotting Package. The FFS identifies the fault bus and
associated “outaged branches” (see table 4); however, the fault sequence was determined by SPP,
and was as follows:
Category B: Apply fault at ranked bus for a time span of CCT cycles and open “outaged
branch”
Category C: Open first “outaged branch” and allow steady state system adjustments. Apply
fault at ranked bus for a time span of CCT cycles and open second “outaged branch”
2014 Stability Study 3
Category D: Apply fault at the ranked bus for a time span of CCT cycles and open all
“outaged branches” at the bus.
Generator rotor speed, rotor angle, real power, and reactive power output were monitored for all SPP
generators during the time domain simulation. Those generators exhibiting rotor speed and angle
instability were marked for further analysis. This analysis consisted of determining and correcting
the cause of instability and is further detailed in Results Section of this report.
Any unstable Category D event generator(s) were disconnected during the simulation and re-
simulated to determine stability for the remaining system.
Member Specified Events
These events were simulated in PTI’s PSS/E Dynamics Package and the PSSPLT Plotting Package.
Generator rotor speed, rotor angle, real power, and reactive power output were monitored for all SPP
generators. Those generators exhibiting rotor speed and angle instability were marked for further
analysis. This analysis consisted of determining and correcting the cause of instability and is further
detailed in Appendix B of this report.
Some events necessitated a change in generation differing from that amount in the powerflow
models. In such cases, an offset amount was included to balance generation prior to event
simulation.
Any unstable Category D event generator(s) were disconnected during the simulation and re-
simulated to determine stability for the remaining system.
Results
Fast Fault Screening (FFS)
The screening identified severe fault locations for the 2015 Light Load and 2020 Summer cases.
These locations (buses) were ranked according to their Ranking Index (RI) and Critical Clearing
Time (CCT) for NERC category B, C, and D contingencies. The results are shown in Appendix A,
Table 1. The outaged element(s) associated with each fault are shown in Appendix C, Table 4 and
are considered only if real power is leaving the faulted bus.
2014 Stability Study 4
Transient Stability Analysis of Most Severe FFS Events
Transient stability analysis was performed on the events identified in Appendix C, Table 4 using
PSS/E’s dynamics package. Those events resulting in instability are discussed below and are shown
in Appendix B, Table 3.
Event 20S-FFS-CATC_15 caused the LPLFUTURE unit owned by Lubbock Power and Light to be
unstable when, with a prior outage of the LPHOLLY - LPSOUTHEAST 230kV line, a fault occurs
on the LPHOLLY 230kV bus and the LPHOLLY - JONES 230kV line is opened. Therefore, an
operating guide is needed such that for a prior outage of the LPHOLLY - LPSOUTHEAST 230kV
line, the output of the LPFUTURE must be curtailed to 400MW until such time that the line is
returned to service. This assumes the LPHOLLY - JONES 230kV line will trip in 6 cycles should
the fault occur. It should be noted that this future generator has not been vetted through SPP’s
Generator Interconnection process and its location in the power flow as well as the dynamics data for
the generator associated with this unit are a proxy for a future unit(s).
Transient Stability Analysis of Member Submitted Events
Members provided eleven (11) Category B, twenty-six (26) Category C, and nineteen (19) Category
D events for examination. Transient stability analysis was performed on these events using PSS/E’s
dynamics package. There was no resulting system instability for member submitted events.
Conclusion
The MDWG 2014 Series 2015 Light Load and 2020 Summer Peak Load Cases were tested and
found to be stable during normal conditions prior to this study, satisfying NERC TPL Category A
requirements.
All Category B FFS and Member Submitted events were found to be stable when the clearing times
were tested, satisfying NERC TPL Category B requirements.
All Category C FFS and Member Submitted events were found to be stable, with the exception of
Category C Event 20S-FFS-CATC_15, which will require an operating guide as described in the
2014 Stability Study 5
results section of this document. The specified mitigation measure, together with all tested stable
events ensures that NERC TPL Category C requirements are satisfied.
All Category D FFS and Member Submitted events were found to be stable thereby satisfying NERC
TPL Category D requirements.
[1] [1] M. Y. Vaiman, A. Gaikwad, "Fast Fault Screening Methodology for Transient Stability Analysis of Bulk Power Systems", Presented at 2013
IEEE Power and Energy General Meeting, pp:1-5.
2014 Stability Study 6
APPENDIX A - Events
Table 1: NERC Category B, C, & D, Fast Fault Scan Results
FFS Event Bus
Number Bus Name BaseKV Transient Analysis Results Clearing
Time(cyc)
Fault-2014-15L-FFS-CATB_20 659101 ANTELOP3 345 Stable 5.0
Fault-2014-15L-FFS-CATB_1 659131 LARAMIE3 345 Stable 6.0
Fault-2014-15L-FFS-CATB_2 510406 N.E.S.-7 345 Stable 8.4
Fault-2014-15L-FFS-CATB_3 507454 TURK 4 138 Stable 7.2
Fault-2014-15L-FFS-CATB_4 532797 WOLFCRK7 345 Stable 6.0
Fault-2014-15L-FFS-CATC_1 659101 ANTELOP3 345 Stable 5.0
Fault-2014-15L-FFS-CATC_2 659131 LARAMIE3 345 Stable 5.0
Fault-2014-15L-FFS-CATC_3 652541 BIGBND24 230 Stable 6.0
Fault-2014-15L-FFS-CATC_4 510406 N.E.S.-7 345 Stable 7.2
Fault-2014-15L-FFS-CATC_5 507454 TURK 4 138 Stable 4.8
Fault-2014-15L-FFS-CATC_6 542982 IATAN 7 345 Stable 3.0
Fault-2014-15L-FFS-CATC_7 532797 WOLFCRK7 345 Stable *4.6
Fault-2014-15L-FFS-CATD_1 659101 ANTELOP3 345 Stable 5.0
Fault-2014-15L-FFS-CATD_2 659131 LARAMIE3 345 Stable 5.0
Fault-2014-15L-FFS-CATD_3 532797 WOLFCRK7 345 Stable 5.0
Fault-2014-15L-FFS-CATD_4 510406 N.E.S.-7 345 Stable 5.0
Fault-2014-15L-FFS-CATD_5 542982 IATAN 7 345 Stable 5.0
Fault-2014-15L-FFS-CATD_6 532766 JEC N 7 345 Stable 5.0
Fault-2014-15L-FFS-CATD_7 507454 TURK 4 138 Stable 8.0
Fault-2014-15L-FFS-CATD_8 645451 S3451 3 345 Stable 5.0
Fault-2014-15L-FFS-CATD_9 512650 GRDA1 7 345 Stable 5.0
Fault-2014-15L-FFS-CATD_10 532853 LAWHILL6 230 Stable 6.0
Fault-2014-15L-FFS-CATD_11 549954 JTEC 5 161 Stable 8.0
Fault-2014-15L-FFS-CATD_12 652509 FTRANDL4 230 Stable 6.0
Fault-2014-15L-FFS-CATD_13 652541 BIGBND24 230 Stable 6.0
Fault-2014-15L-FFS-CATD_15 509807 ONETA--7 345 Stable 8.4
Fault-2014-20S-FFS-CATB_51 507789 STLGENS4 138 Stable 8.0
Fault-2014-20S-FFS-CATB_52 659332 WATFRDCMBC4X 230 Stable 6.0
Fault-2014-20S-FFS-CATB_53 652540 BIGBND14 230 Stable 6.0
Fault-2014-20S-FFS-CATB_54 547503 RIV452T 5 161 Stable 8.0
Fault-2014-20S-FFS-CATB_55 547501 RIV453 5 161 Stable 8.0
Fault-2014-20S-FFS-CATB_56 533422 HEC U4 3 115 Stable 8.0
Fault-2014-20S-FFS-CATB_1 659131 LARAMIE3 345 Stable 3.0
Fault-2014-20S-FFS-CATB_2 532766 JEC N 7 345 Stable 4.8
Fault-2014-20S-FFS-CATB_3 532852 JEC 6 230 Stable 8.4
2014 Stability Study 7
Fault-2014-20S-FFS-CATB_4 542982 IATAN 7 345 Stable 8.4
Fault-2014-20S-FFS-CATB_5 523853 FINNEY 7 345 Stable 8.4
Fault-2014-20S-FFS-CATB_6 505502 TRUMAN 5 161 Stable 8.4
Fault-2014-20S-FFS-CATB_7 507454 TURK 4 138 Stable 7.2
Fault-2014-20S-FFS-CATB_8 547476 ASB349 5 161 Stable 8.4
Fault-2014-20S-FFS-CATB_10 659101 ANTELOP3 345 Stable 8.4
Fault-2014-20S-FFS-CATB_11 542981 LACYGNE7 345 Stable 8.4
Fault-2014-20S-FFS-CATB_13 532797 WOLFCRK7 345 Stable 6.0
Fault-2014-20S-FFS-CATC_1 659131 LARAMIE3 345 Stable 5.0
Fault-2014-20S-FFS-CATC_2 507789 STLGENS4 138 Stable 9.0
Fault-2014-20S-FFS-CATC_3 652216 WATFORD4 230 Stable 6.0
Fault-2014-20S-FFS-CATC_4 659332 WATFRDCMBC4X 230 Stable 7.0
Fault-2014-20S-FFS-CATC_5 652540 BIGBND14 230 Stable 7.0
Fault-2014-20S-FFS-CATC_6 547501 RIV453 5 161 Stable 9.0
Fault-2014-20S-FFS-CATC_7 547503 RIV452T 5 161 Stable 9.0
Fault-2014-20S-FFS-CATC_8 533422 HEC U4 3 115 Stable 9.0
Fault-2014-20S-FFS-CATC_9 505502 TRUMAN 5 161 Stable 9.0
Fault-2014-20S-FFS-CATC_10 532766 JEC N 7 345 Stable *4.6
Fault-2014-20S-FFS-CATC_11 542982 IATAN 7 345 Stable 7.2
Fault-2014-20S-FFS-CATC_12 531445 GRDNCTY3 115 Stable 6.0
Fault-2014-20S-FFS-CATC_13 532852 JEC 6 230 Stable 7.2
Fault-2014-20S-FFS-CATC_14 542981 LACYGNE7 345 Stable 4.8
Fault-2014-20S-FFS-CATC_15 522870 LP-HOLLY 6 230 Unstable 0.6
Fault-2014-20S-FFS-CATC_16 547476 ASB349 5 161 Stable 8.4
Fault-2014-20S-FFS-CATC_18 523853 FINNEY 7 345 Stable 8.4
Fault-2014-20S-FFS-CATC_19 507454 TURK 4 138 Stable 6.0
Fault-2014-20S-FFS-CATC_20 659101 ANTELOP3 345 Stable 7.2
Fault-2014-20S-FFS-CATC_21 645458 S3458 3 345 Stable 8.4
Fault-2014-20S-FFS-CATC_22 532797 WOLFCRK7 345 Stable *4.6
Fault-2014-20S-FFS-CATC_27 659105 LELANDO3 345 Stable 8.4
Fault-2014-20S-FFS-CATD_1 532766 JEC N 7 345 Stable 5.0
Fault-2014-20S-FFS-CATD_2 542981 LACYGNE7 345 Stable 5.0
Fault-2014-20S-FFS-CATD_3 542982 IATAN 7 345 Stable 5.0
Fault-2014-20S-FFS-CATD_4 645458 S3458 3 345 Stable 5.0
Fault-2014-20S-FFS-CATD_5 532797 WOLFCRK7 345 Stable 5.0
Fault-2014-20S-FFS-CATD_6 659101 ANTELOP3 345 Stable 5.0
Fault-2014-20S-FFS-CATD_7 510396 N.E.S.-4 138 Stable 8.0
Fault-2014-20S-FFS-CATD_8 532852 JEC 6 230 Stable 6.0
Fault-2014-20S-FFS-CATD_9 507454 TURK 4 138 Stable 8.0
Fault-2014-20S-FFS-CATD_10 659131 LARAMIE3 345 Stable 5.0
Fault-2014-20S-FFS-CATD_11 547498 STL439 5 161 Stable 8.0
Fault-2014-20S-FFS-CATD_12 645451 S3451 3 345 Stable 5.0
Fault-2014-20S-FFS-CATD_13 652519 OAHE 4 230 Stable 6.0
2014 Stability Study 8
Fault-2014-20S-FFS-CATD_14 507789 STLGENS4 138 Stable 8.0
Fault-2014-20S-FFS-CATD_15 522870 LP-HOLLY 6 230 Stable 6.0
Fault-2014-20S-FFS-CATD_16 510406 N.E.S.-7 345 Stable 5.0
Fault-2014-20S-FFS-CATD_17 549954 JTEC 5 161 Stable 8.0
Fault-2014-20S-FFS-CATD_18 520948 HUGO PP4 138 Stable 8.0
Fault-2014-20S-FFS-CATD_19 652216 WATFORD4 230 Stable 6.0
Fault-2014-20S-FFS-CATD_20 532853 LAWHILL6 230 Stable 6.0
Fault-2014-20S-FFS-CATD_21 520999 MOORLND4 138 Stable 8.0
Fault-2014-20S-FFS-CATD_22 542995 MONTROS5 161 Stable 8.0
Fault-2014-20S-FFS-CATD_23 652441 GARRISN4 230 Stable 6.0
Fault-2014-20S-FFS-CATD_24 541341 S.HARP 5 161 Stable 8.0
Fault-2014-20S-FFS-CATD_25 659332 WATFRDCMBC4X 230 Stable 6.0
Fault-2014-20S-FFS-CATD_26 652540 BIGBND14 230 Stable 6.0
Fault-2014-20S-FFS-CATD_27 546653 NEARMAN5 161 Stable 8.0
Fault-2014-20S-FFS-CATD_28 531445 GRDNCTY3 115 Stable 8.0
Fault-2014-20S-FFS-CATD_29 547501 RIV453 5 161 Stable 8.0
Fault-2014-20S-FFS-CATD_30 547503 RIV452T 5 161 Stable 8.0
Fault-2014-20S-FFS-CATD_31 533180 TEC E 3 115 Stable 8.0
Fault-2014-20S-FFS-CATD_32 547476 ASB349 5 161 Stable 8.0
Fault-2014-20S-FFS-CATD_33 511437 COMANC-4 138 Stable 8.0
Fault-2014-20S-FFS-CATD_34 533422 HEC U4 3 115 Stable 8.0
Fault-2014-20S-FFS-CATD_35 505502 TRUMAN 5 161 Stable 8.0
Fault-2014-20S-FFS-CATD_38 523853 FINNEY 7 345 Stable 8.4
Fault-2014-20S-FFS-CATD_39 659105 LELANDO3 345 Stable 4.8
Fault-2014-20S-FFS-CATD_40 505460 BULL SH5 161 Stable 7.2
* The individual member supplied this CCT
2014 Stability Study 9
Table 2: Member Submitted NERC Category B, C, and D Events
Event Contingency Description Transient
Analysis Results
Fault-2014-15L-MS-CATB_1 3-Ø fault on the 230 kV side of the Knoll 230/115 kV transformer with normal clearing.
Stable
Fault-2014-15L-MS-CATB_2 A 3 cycle, 3-phase fault at the 103rd & Rokeby 345 kV end of the 103rd & Rokeby – S3458 345 kV line.
Stable
Fault-2014-15L-MS-CATB_3 3-Ø fault at S3451 on T3 transformer. Normal clearing.
Stable
Fault-2014-15L-MS-CATB_4 3-Ø fault at S1206 on the S1206-S1232 line. Normal clearing.
Stable
Fault-2014-15L-MS-CATB_5 N01A : 3PH fault at GGS on GGS-Sweetwater 345 kV Circuit #1; Normal clearing; No reclose attempts
Stable
Fault-2014-15L-MS-CATB_6 N07A : 3PH fault at GGS on GGS-Red Willow 345 kV; Normal clearing; No reclose attempts
Stable
Fault-2014-15L-MS-CATB_7 N25A : 3PH fault at GGS on GGS-North Platte 230 kV Circuit #1; Normal clearing; No reclose attempts
Stable
Fault-2014-15L-MS-CATB_8 3PH fault at GGS on high side of GGS 345/230 kV T-1 transformer; Normal clearing; No reclose attempts
Stable
Fault-2014-15L-MS-CATB_9 Fault on FINNEY-HOLCOMB followed by Line 525832 to 511456 trip at 4 cycles
Stable
Fault-2014-15L-MS-CATB_10 Fault on POTTER_CO-HITCHLAND followed by Line 523961 TO BUS 523097 at 4 cycles
Stable
Fault-2014-15L-MS-CATB_11 Fault on HITCHLAND-WOODWARD followed by Line 523097 TO WOODWARD 345kV BUS 515375 trip at 4 cycles
Stable
Fault-2014-15L-MS-CATC_1
SLG fault w/stuck breaker at Stranger Creek 345 kV (532772); trip Stranger Creek 345-115 kV TX #1 at 4.6 cycles (532772-533268-532811); Clear fault and trip Stranger Creek 345-115 kV TX #3 (532772-533268-532816) at 14.6 cycles;
Stable
Fault-2014-15L-MS-CATC_2 3-Ø fault at Wolf Creek 345 kV (532797) for 4.6 cycles; Trip Wolf Creek-Benton line (532797-532791); No reclosing;
Stable
Fault-2014-15L-MS-CATC_3
Reduce Wolf Creek output to 800 MW (Transmission Operating Directive 300); 3-Ø fault for 4.6 cycles at Wolf Creek 345 kV (532797); Trip Wolf Creek-Waverly Wind farm 345 kV line (532797-532799); No reclosing
Stable
Fault-2014-15L-MS-CATC_4 3-Ø fault at Wolf Creek 345 kV for 4.6 cycles (532797); Trip Wolf Creek-Waverly Wind farm 345 kV line (532797-532799); No reclosing;
Stable
Fault-2014-15L-MS-CATC_5
Reduce Wolf Creek output to 800 MW (Transmission Operating Directive 302); 3-Ø fault at Wolf Creek 345 kV (532797) for 4.6 cycles; Trip Wolf Creek-Benton 345 kV (532797-532791); No reclosing
Stable
2014 Stability Study 10
Fault-2014-15L-MS-CATC_6 3-Ø fault at Wolf Creek for 4.6 Cycles (532797); Trip Wolf Creek-Rose Hill line (532797-532794) ; No reclosing;
Stable
Fault-2014-15L-MS-CATC_7
Reduce Wolf Creek output to 800 MW (Transmission Operating Directive 301); 3-Ø fault at Wolf Creek 345 kV (532797) for 4.6 cycles; Trip Wolf Creek-Waverly Wind farm 345 kV line (532797-532799); No reclosing
Stable
Fault-2014-15L-MS-CATC_8
SLG fault w/stuck breaker at Wolf Creek 345 kV (532797); trip Wolf Creek-Rose Hill 345 kV line (532797-532794) at 4.6 cycles; Clear fault at 10.1 cycles; Wolf Creek 345-40 breaker failure
Stable
Fault-2014-15L-MS-CATC_9
3-Ø fault at JEC 345 kV for 4.6 cycles (532766); Trip JEC-Summit 345 kV line (532766-532773); No reclosing; 3-Ø fault at JEC 345 kV (532766) for 4.6 cycles; Trip JEC-Morris 345 kV line (532766-532770); No reclosing;
Stable
Fault-2014-15L-MS-CATC_10
SLG fault w/stuck breaker at JEC 345 kV (532766); trip JEC-Hoyt 345 kV line (532766-532765) at 4.6 cycles; Clear fault at 13 cycles and trip JEC Unit 2 (532766-532652); (JEC 345-16 breaker failure)
Stable
Fault-2014-15L-MS-CATC_11 SLG fault on Knoll-Smoky 230 kV line with Knoll breaker 6001 failure.
Stable
Fault-2014-15L-MS-CATC_12 SLG fault on Rice-Circle 230 kV line with Rice breaker 6045 failure.
Stable
Fault-2014-15L-MS-CATC_13
SLG fault at S3458 on the S3458 - Cooper Line, followed by a stuck breaker and the opening of the west bus at S3458. Fault Admittance 643 - j 7971 MVA for 2015LL and 683 - j 8311 MVA for 2020SP for initial fault. Fault Admittance 430 - j 6449 MVA for 2015LL and 469 - j 6832 MVA for 2020SP after opening S3458 - Cooper.
Stable
Fault-2014-15L-MS-CATC_14 Prior outage of S3451 - Raun 345 kV. 3-Ø fault at S3451 on T3 transformer. Normal clearing.
Stable
Fault-2014-15L-MS-CATC_15
N915 : SLG fault at GGS on GGS-Sweetwater 345 kV Circuit #2, Stuck Breaker (GGS 3322), Drop GGS-Red Willow 345 kV line; Delayed clearing; No reclose attempts
Stable
Fault-2014-15L-MS-CATC_16 A 3 cycle, 3-phase fault at the Wagener 345 kV end of the Wagener – 103rd & Rokeby 345 kV line
Stable
Fault-2014-15L-MS-CATC_17 A 3 cycle, 3-phase fault at the 103rd & Rokeby 345 kV end of the 103rd & Rokeby – S3458 345 kV line
Stable
Fault-2014-15L-MS-CATC_18 Breaker #3003 fails, and the NW 68th & Holdrege 345/115 kV autotransformer is opened at 10 cycles to clear the fault.
Stable
Fault-2014-15L-MS-CATC_19 SLG Fault at GRDA 1, stuck breaker and trip line from Tonnece-GRDA, GRDA transformer #1 and GRDA-Tulsa and GRDA-Sportsman line trip
Stable
2014 Stability Study 11
Fault-2014-15L-MS-CATC_20 SLG Fault at GRDA 1, stuck breaker and trip line from Tulsa-GRDA, GRDA transformer #1 and GRDA-Tonnece and GRDA-Sportsman line trip
Stable
Fault-2014-15L-MS-CATC_21 SLG Fault at GRDA 1, stuck breaker and trip line from Sportsman-GRDA, GRDA transformer #1 and GRDA-Tulsa and GRDA-Tonnece line trip
Stable
Fault-2014-15L-MS-CATC_22 Prior outage of Northeastern Station - Tulsa North 345 kV; 3-phase fault and trip Northeastern Station - Oneta 345 kV. Northeastern generation at Pmax
Stable
Fault-2014-15L-MS-CATC_23 Prior outage of Northeastern Station - Tulsa North 345 kV; 3-phase fault and trip Northeastern Station - Delaware 345 kV. Northeastern generation at Pmax
Stable
Fault-2014-15L-MS-CATC_24 Prior outage of Riverside Station - Sapulpa Rd 345 kV; 3-phase fault and trip Riverside Station - Pecan Creek 345 kV. Riverside (Cogentrix) generation at Pmax
Stable
Fault-2014-15L-MS-CATC_25 3-phase fault and trip Northeastern Station - Tulsa North 345 / 138 kV DCT (90-909 & 81-822). Northeastern generation at Pmax.
Stable
Fault-2014-15L-MS-CATC_26
Phase-to-ground fault Oneta - Riverside Station 345 kV with CB (#3405A) at Oneta. 15-cycle delayed clearing removing Oneta - Clarksville 345 kV. Oneta generation at Pmax
Stable
Fault-2014-15L-MS-CATD_1
Phase-to-ground fault Riverside Station - Red Bud 345 kV with CB (#3405A) at Riverside. 15-cycle delayed clearing removing Riverside - Sapulpa 345 kV. Riverside (Cogentrix) generation at Pmax.
Stable
Fault-2014-15L-MS-CATD_2 Fault at TUCO-OKU followed by line 525832 TO BUS 511456 and Transformer 525832 TO BUS 525830 TO BUS 525824 CKT 1 trip
Stable
Fault-2014-15L-MS-CATD_3 Fault at TUCO-WOODWARD followed by line 515458 TO BUS 525832 CKT 1 and line trip 515458 TO BUS 515375 CKT 1
Stable
Fault-2014-15L-MS-CATD_4 3-Ø fault at South Hays 230 kV bus resulting in the loss of the South Hays 230 kV substation and 230/115 kV transformer.
Stable
Fault-2014-15L-MS-CATD_5 3-Ø fault on the 115 kV side of the Rice 230/115 kV transformer with Rice breaker 3062 failure.
Stable
Fault-2014-15L-MS-CATD_6 3-Ø fault at S3458 on the S3458 - Cooper line, followed by a stuck breaker and the opening of the west bus at S3458.
Stable
Fault-2014-15L-MS-CATD_7 3-Ø fault at JEC 345 (532766). Clear fault and all 345 kV lines and transformers at 4.6 cycles
Stable
Fault-2014-15L-MS-CATD_8 3-Ø fault at Wolf Creek 345 (532797). Clear fault and all 345 kV lines and transformers at 4.6 cycles
Stable
Fault-2014-15L-MS-CATD_9 3-Ø fault at Wichita 345 kV (532796). Clear fault and all 345 kV lines and transformers at 4.6 cycles
Stable
Fault-2014-15L-MS-CATD_10 A 23-cycle, 3-phase fault, with Delayed Clearing, on the Moore 345 kV end of Moore-103rd & Rokeby 345
Stable
2014 Stability Study 12
kV
Fault-2014-15L-MS-CATD_11 3-phase fault Tulsa SE 138 kV bus tie CB (#1345B) and clear entire station
Stable
Fault-2014-15L-MS-CATD_12 3-phase fault Tulsa PS 138 kV bus tie CB (#1349B) and clear entire station
Stable
Fault-2014-15L-MS-CATD_13 3-phase fault and trip Oneta 345 kV Station Stable
Fault-2014-15L-MS-CATD_14 3-phase fault and trip Oneta 138 kV Station Stable
Fault-2014-15L-MS-CATD_15 3-phase fault and trip Riverside 138 kV Station Stable
Fault-2014-15L-MS-CATD_16 3-phase fault and trip Pittsburg 345 kV Station Stable
Fault-2014-15L-MS-CATD_17 3-phase fault and trip Tulsa North 138 kV Station Stable
Fault-2014-15L-MS-CATD_18 3-phase fault and trip Valliant 345 kV Station Stable
Fault-2014-15L-MS-CATD_19 3-phase fault and trip Oklaunion - Lawton Eastside 345 kV with SPS failure
Stable
2014 Stability Study 13
APPENDIX B - Results
Table 3: Unstable Events
EVENT Unstable Units
Owner Mitigation
20S-FFS-CATC_15 LPLFUTURE Lubbock Power and Light
Should this unit be installed as modeled, an operating guide will be
required as described in the results section of this
document
2014 Stability Study 14
APPENDIX C – Outaged Branches
Table 4: NERC Category B, C, & D, FFS Outaged Branches
Event Bus Number Bus Name BaseKV Branch Outage
Power Flow, MW
Fault-2014-15L-FFS-CATB_20 659101 ANTELOP3 345 Branch 659101-659183 1 383
Fault-2014-15L-FFS-CATB_1 659131 LARAMIE3 345 Branch 659131-659135 1 277
Fault-2014-15L-FFS-CATB_2 510406 N.E.S.-7 345 Branch 509852-510406 1 504
Fault-2014-15L-FFS-CATB_3 507454 TURK 4 138 Transformer 507454-507455-507457 1 246
Fault-2014-15L-FFS-CATB_4 532797 WOLFCRK7 345 Branch 532794-532797 1 430
Fault-2014-15L-FFS-CATC_1 659101 ANTELOP3 345 Branch 659101-659183 1 383
Transformer 659101-659218 1 55
Fault-2014-15L-FFS-CATC_2 659131 LARAMIE3 345 Branch 659131-659135 1 277
Branch 659131-659133 1 188
Fault-2014-15L-FFS-CATC_3 652541 BIGBND24 230 Branch 652507-652541 1 188
Fault-2014-15L-FFS-CATC_4 510406 N.E.S.-7 345 Branch 509852-510406 1 504
Branch 510380-510406 1 261
Fault-2014-15L-FFS-CATC_5 507454 TURK 4 138 Transformer 507454-507455-507457 1 246
Branch 507454-508080 1 100
Fault-2014-15L-FFS-CATC_6 542982 IATAN 7 345 Branch 532772-542982 1 455
Branch 541400-542982 1 291
Fault-2014-15L-FFS-CATC_7 532797 WOLFCRK7 345 Branch 532794-532797 1 430
Branch 532791-532797 1 388
Fault-2014-15L-FFS-CATD_1 659101 ANTELOP3 345 Branch 659101-659183 1 383
Transformer 659101-659218 1 55
Transformer 659101-659212 1 42
Branch 659101-659105 1 39
Branch 659101-659105 2 39
Transformer 659101-659230 1 30
Branch 659101-659120 1 30
Fault-2014-15L-FFS-CATD_2 659131 LARAMIE3 345 Branch 659131-659135 1 277
Branch 659131-659133 1 188
Fault-2014-15L-FFS-CATD_3 532797 WOLFCRK7 345 Branch 532794-532797 1 430
Branch 532791-532797 1 388
Branch 532797-532799 1 367
Transformer 532797-533653 1 48
Fault-2014-15L-FFS-CATD_4 510406 N.E.S.-7 345 Branch 509852-510406 1 504
2014 Stability Study 15
Branch 510380-510406 1 261
Branch 509807-510406 1 164
Fault-2014-15L-FFS-CATD_5 542982 IATAN 7 345 Branch 532772-542982 1 455
Branch 541400-542982 1 291
Transformer 541150-541350-542982 11 153
Fault-2014-15L-FFS-CATD_6 532766 JEC N 7 345 Branch 532766-532773 1 197
Branch 532766-532770 1 168
Branch 532765-532766 1 91
Transformer 532766-532806-532852 1 79
Transformer 532766-532805-532852 1 79
Transformer 532652-532766 1 0
Fault-2014-15L-FFS-CATD_7 507454 TURK 4 138 Transformer 507454-507455-507457 1 246
Branch 507454-508080 1 100
Branch 507428-507454 1 98
Branch 507454-508105 1 97
Transformer 507454-507456-507458 1 73
Fault-2014-15L-FFS-CATD_8 645451 S3451 3 345 Branch 645451-645459 1 121
Transformer 645451-646251-648251 1 102
Transformer 645451-646251-648351 1 102
Branch 635200-645451 1 101
Branch 645451-645454 1 91
Fault-2014-15L-FFS-CATD_9 512650 GRDA1 7 345 Branch 512650-512750 1 137
Branch 300740-512650 1 122
Transformer 512650-512656-512826 2 115
Transformer 512650-512656-512821 1 114
Branch 509852-512650 1 8
Fault-2014-15L-FFS-CATD_10 532853 LAWHILL6 230 Branch 532853-532856 1 141
Transformer 532853-532882-533250 1 118
Branch 532853-532855 1 85
Fault-2014-15L-FFS-CATD_11 549954 JTEC 5 161 Branch 549954-549960 1 97
Branch 549954-549969 1 65
Branch 549954-549961 1 38
Branch 300348-549954 1 33
Transformer 549891-549954 1 0
Fault-2014-15L-FFS-CATD_12 652509 FTRANDL4 230 Branch 652509-652526 1 100
Branch 652509-652565 1 56
Branch 640540-652509 1 21
2014 Stability Study 16
Transformer 652509-652510 2 19
Transformer 652509-652510 1 19
Branch 652509-652516 1 5
Branch 652507-652509 1 0
Fault-2014-15L-FFS-CATD_13 652541 BIGBND24 230 Branch 652507-652541 1 188
Fault-2014-15L-FFS-CATD_15 509807 ONETA--7 345 Branch 509782-509807 1 252
Transformer 509806-509807-509874 3 207
Transformer 509806-509807-509881 1 202
Branch 509745-509807 1 199
Transformer 509806-509807-509868 2 199
Fault-2014-20S-FFS-CATB_51 507789 STLGENS4 138 Branch 507711-507789 1 506
Fault-2014-20S-FFS-CATB_52 659332 WATFRDCMBC4X 230 Branch 652216-659332 1 294
Fault-2014-20S-FFS-CATB_53 652540 BIGBND14 230 Branch 652507-652540 1 259
Fault-2014-20S-FFS-CATB_54 547503 RIV452T 5 161 Branch 547469-547503 1 210
Fault-2014-20S-FFS-CATB_55 547501 RIV453 5 161 Branch 547501-547503 1 210
Fault-2014-20S-FFS-CATB_56 533422 HEC U4 3 115 Branch 533413-533422 1 161
Fault-2014-20S-FFS-CATB_1 659131 LARAMIE3 345 Branch 659131-659135 1 330
Fault-2014-20S-FFS-CATB_2 532766 JEC N 7 345 Branch 532765-532766 1 647
Fault-2014-20S-FFS-CATB_3 532852 JEC 6 230 Branch 532852-532861 1 347
Fault-2014-20S-FFS-CATB_4 542982 IATAN 7 345 Branch 542980-542982 1 540
Fault-2014-20S-FFS-CATB_5 523853 FINNEY 7 345 Branch 523097-523853 1 204
Fault-2014-20S-FFS-CATB_6 505502 TRUMAN 5 161 Branch 505502-541314 1 116
Fault-2014-20S-FFS-CATB_7 507454 TURK 4 138 Transformer 507454-507455-507457 1 189
Fault-2014-20S-FFS-CATB_8 547476 ASB349 5 161 Branch 532932-547476 1 86
Fault-2014-20S-FFS-CATB_10 659101 ANTELOP3 345 Branch 659101-659183 1 270
Fault-2014-20S-FFS-CATB_11 542981 LACYGNE7 345 Branch 542968-542981 1 757
Fault-2014-20S-FFS-CATB_13 532797 WOLFCRK7 345 Branch 532794-532797 1 458
Fault-2014-20S-FFS-CATC_1 659131 LARAMIE3 345 Branch 659131-659135 1 330
Branch 659131-659133 1 240
Fault-2014-20S-FFS-CATC_2 507789 STLGENS4 138 Branch 507711-507789 1 506
Fault-2014-20S-FFS-CATC_3 652216 WATFORD4 230 Branch 652216-652400 1 207
Branch 652216-659302 1 47
Fault-2014-20S-FFS-CATC_4 659332 WATFRDCMBC4X 230 Branch 652216-659332 1 294
Fault-2014-20S-FFS-CATC_5 652540 BIGBND14 230 Branch 652507-652540 1 259
Fault-2014-20S-FFS-CATC_6 547501 RIV453 5 161 Branch 547501-547503 1 210
Fault-2014-20S-FFS-CATC_7 547503 RIV452T 5 161 Branch 547469-547503 1 210
Fault-2014-20S-FFS-CATC_8 533422 HEC U4 3 115 Branch 533413-533422 1 161
Fault-2014-20S-FFS-CATC_9 505502 TRUMAN 5 161 Branch 505502-541314 1 116
Branch 300071-505502 1 45
Fault-2014-20S-FFS-CATC_10 532766 JEC N 7 345 Branch 532765-532766 1 647
2014 Stability Study 17
Branch 532766-532767 1 491
Fault-2014-20S-FFS-CATC_11 542982 IATAN 7 345 Branch 542980-542982 1 540
Branch 532772-542982 1 444
Fault-2014-20S-FFS-CATC_12 531445 GRDNCTY3 115 Branch 531445-531480 1 96
Branch 531445-531448 1 48
Fault-2014-20S-FFS-CATC_13 532852 JEC 6 230 Branch 532852-532861 1 347
Branch 532851-532852 1 285
Fault-2014-20S-FFS-CATC_14 542981 LACYGNE7 345 Branch 542968-542981 1 757
Branch 542965-542981 1 563
Fault-2014-20S-FFS-CATC_15 522870 LP-HOLLY 6 230 Branch 522861-522870 1 210
Branch 522870-526337 1 198
Fault-2014-20S-FFS-CATC_16 547476 ASB349 5 161 Branch 532932-547476 1 86
Branch 547476-547491 1 71
Fault-2014-20S-FFS-CATC_18 523853 FINNEY 7 345 Branch 523097-523853 1 204
Fault-2014-20S-FFS-CATC_19 507454 TURK 4 138 Transformer 507454-507455-507457 1 189
Branch 507428-507454 1 140
Fault-2014-20S-FFS-CATC_20 659101 ANTELOP3 345 Branch 659101-659183 2 270
Branch 659101-659183 1 247
Fault-2014-20S-FFS-CATC_21 645458 S3458 3 345 Branch 645458-650189 1 413
Branch 645456-645458 1 368
Fault-2014-20S-FFS-CATC_22 532797 WOLFCRK7 345 Branch 532794-532797 1 458
Branch 532791-532797 1 402
Fault-2014-20S-FFS-CATC_27 659105 LELANDO3 345 Branch 659105-659160 1 148
Transformer 659105-659106-659201 1 128
Fault-2014-20S-FFS-CATD_1 532766 JEC N 7 345 Branch 532765-532766 1 647
Branch 532766-532767 1 491
Branch 532766-532770 1 303
Fault-2014-20S-FFS-CATD_2 542981 LACYGNE7 345 Branch 542968-542981 1 757
Branch 542965-542981 1 563
Branch 532793-542981 1 313
Fault-2014-20S-FFS-CATD_3 542982 IATAN 7 345 Branch 542980-542982 1 540
Branch 532772-542982 1 444
Branch 541400-542982 1 381
Transformer 541150-541350-542982 11 189
Fault-2014-20S-FFS-CATD_4 645458 S3458 3 345 Branch 645458-650189 1 413
Branch 645456-645458 1 368
Branch 645458-645740 1 210
Branch 640139-645458 1 191
Branch 541197-645458 1 144
Fault-2014-20S-FFS-CATD_5 532797 WOLFCRK7 345 Branch 532794-532797 1 458
Branch 532791-532797 1 402
2014 Stability Study 18
Branch 532797-532799 1 251
Transformer 532797-533653 1 76
Fault-2014-20S-FFS-CATD_6 659101 ANTELOP3 345 Branch 659101-659183 2 270
Branch 659101-659183 1 247
Branch 659101-659120 1 120
Transformer 659101-659218 1 55
Transformer 659101-659212 1 42
Branch 659101-659105 1 38
Branch 659101-659105 2 38
Transformer 659101-659230 1 30
Fault-2014-20S-FFS-CATD_7 510396 N.E.S.-4 138 Branch 510385-510396 1 153
Branch 300795-510396 1 116
Branch 509843-510396 1 111
Branch 510384-510396 1 111
Branch 509864-510396 1 108
Branch 509860-510396 1 101
Branch 509817-510396 1 74
Branch 510396-510413 1 67
Fault-2014-20S-FFS-CATD_8 532852 JEC 6 230 Branch 532852-532861 1 347
Branch 532851-532852 1 285
Transformer 532766-532806-532852 1 18
Transformer 532766-532805-532852 1 18
Fault-2014-20S-FFS-CATD_9 507454 TURK 4 138 Transformer 507454-507455-507457 1 189
Branch 507428-507454 1 140
Branch 507454-508105 1 124
Branch 507454-508080 1 113
Transformer 507454-507456-507458 1 49
Fault-2014-20S-FFS-CATD_10 659131 LARAMIE3 345 Branch 659131-659135 1 330
Branch 659131-659133 1 240
Fault-2014-20S-FFS-CATD_11 547498 STL439 5 161 Branch 547483-547498 1 224
Branch 547470-547498 1 164
Branch 547483-547498 2 152
Branch 547469-547498 1 48
Fault-2014-20S-FFS-CATD_12 645451 S3451 3 345 Transformer 645451-646251-648251 1 201
Transformer 645451-646251-648351 1 200
Branch 645451-645459 1 61
Branch 635200-645451 1 55
Branch 645451-645454 1 54
Fault-2014-20S-FFS-CATD_13 652519 OAHE 4 230 Branch 652507-652519 3 94
2014 Stability Study 19
Branch 652507-652519 4 94
Branch 652507-652519 2 92
Branch 652507-652519 1 92
Branch 652519-652521 1 75
Branch 652488-652519 1 50
Transformer 652519-652520-652589 1 41
Transformer 652519-652520-652589 2 41
Fault-2014-20S-FFS-CATD_14 507789 STLGENS4 138 Branch 507711-507789 1 506
Fault-2014-20S-FFS-CATD_15 522870 LP-HOLLY 6 230 Branch 522861-522870 1 210
Branch 522870-526337 1 198
Transformer 522865-522866-522870 1 92
Fault-2014-20S-FFS-CATD_16 510406 N.E.S.-7 345 Branch 510380-510406 1 270
Branch 509852-510406 1 180
Branch 509807-510406 1 18
Fault-2014-20S-FFS-CATD_17 549954 JTEC 5 161 Branch 549954-549960 1 202
Branch 549954-549969 1 152
Branch 300348-549954 1 76
Branch 549954-549961 1 25
Transformer 549891-549954 1 0
Fault-2014-20S-FFS-CATD_18 520948 HUGO PP4 138 Branch 520918-520948 1 118
Transformer 520948-521157-521189 1 107
Branch 520948-521036 1 99
Branch 510918-520948 1 67
Branch 520948-521079 1 49
Fault-2014-20S-FFS-CATD_19 652216 WATFORD4 230 Branch 652216-652400 1 207
Branch 652216-659302 1 47
Transformer 652216-652408-652472 1 19
Transformer 652216-652408-652471 1 19
Fault-2014-20S-FFS-CATD_20 532853 LAWHILL6 230 Transformer 532853-532882-533250 1 179
Branch 532853-532855 1 135
Branch 532853-532856 1 30
Fault-2014-20S-FFS-CATD_21 520999 MOORLND4 138 Branch 520201-520999 1 84
Branch 520999-521128 1 59
Branch 514788-520999 1 47
Branch 520957-520999 1 44
Branch 520848-520999 1 42
Branch 520999-521065 1 29
Transformer 520995-520999-521180 1 24
2014 Stability Study 20
Branch 515785-520999 1 12
Fault-2014-20S-FFS-CATD_22 542995 MONTROS5 161 Branch 300071-542995 1 193
Branch 541317-542995 1 57
Branch 541245-542995 1 31
Branch 541207-542995 1 24
Branch 542969-542995 1 20
Fault-2014-20S-FFS-CATD_23 652441 GARRISN4 230 Branch 652441-652444 1 145
Branch 652441-652466 1 107
Transformer 652441-652442 1 54
Branch 652441-659106 1 1
Fault-2014-20S-FFS-CATD_24 541341 S.HARP 5 161 Branch 541341-541344 1 116
Branch 541341-542969 1 89
Branch 541207-541341 1 78
Transformer 541341-541343 1 16
Fault-2014-20S-FFS-CATD_25 659332 WATFRDCMBC4X 230 Branch 652216-659332 1 294
Fault-2014-20S-FFS-CATD_26 652540 BIGBND14 230 Branch 652507-652540 1 259
Fault-2014-20S-FFS-CATD_27 546653 NEARMAN5 161 Branch 546653-546654 1 79
Branch 546653-546656 1 40
Branch 546652-546653 1 39
Branch 546653-546669 1 26
Branch 546653-546669 2 26
Fault-2014-20S-FFS-CATD_28 531445 GRDNCTY3 115 Branch 531445-531480 1 96
Branch 531445-531448 1 48
Transformer 531254-531421-531445 1 32
Branch 531445-531476 1 24
Transformer 531258-531423-531445 1 4
Fault-2014-20S-FFS-CATD_29 547501 RIV453 5 161 Branch 547501-547503 1 210
Fault-2014-20S-FFS-CATD_30 547503 RIV452T 5 161 Branch 547469-547503 1 210
Fault-2014-20S-FFS-CATD_31 533180 TEC E 3 115 Branch 533180-533182 1 146
Transformer 533180-533448-533462 1 31
Branch 533180-533192 1 18
Branch 533180-533252 1 2
Fault-2014-20S-FFS-CATD_32 547476 ASB349 5 161 Branch 532932-547476 1 86
Branch 547476-547491 1 71
Branch 547476-547477 1 27
Fault-2014-20S-FFS-CATD_33 511437 COMANC-4 138 Branch 511437-511488 1 80
Branch 511437-511494 1 51
Branch 511437-511467 1 38
Fault-2014-20S-FFS-CATD_34 533422 HEC U4 3 115 Branch 533413-533422 1 161
Fault-2014-20S-FFS-CATD_35 505502 TRUMAN 5 161 Branch 505502-541314 1 116
Branch 300071-505502 1 45
2014 Stability Study 21
Fault-2014-20S-FFS-CATD_38 523853 FINNEY 7 345 Branch 523097-523853 1 204
Fault-2014-20S-FFS-CATD_39 659105 LELANDO3 345 Branch 659105-659160 1 148
Transformer 659105-659106-659201 1 128
Transformer 659105-659106-659202 1 109
Branch 652506-659105 1 82
Fault-2014-20S-FFS-CATD_40 505460 BULL SH5 161 Branch 338123-505460 1 90
Branch 338813-505460 1 82
Branch 300081-505460 1 71
Branch 338120-505460 1 68
Branch 504440-505460 1 18
2014 Stability Study 22
APPENDIX D: Plots and FFS Data
Generator responses showing the six (6) largest excursions for rotor speed, rotor angle, electrical
power, and reactive power output were plotted in .pdf format and posted on TrueShare at:
TWG >TPL Compliance Reports>2014 TPL Assessment>Stability Results
The raw results of the FFS Scans are also posted on the Trueshare Site.