HAE SSR (RAS)

• Presentation to: WECC REMEDIAL ACTION SCHEME RELIABILITY SUBCOMMITTEE (RASRS) November 5, 2019

• Alex Fratkin– Transmission Planning

• Minghao Wu– System Protection

• Lee Onsager-Telecommunications

1

BACKGROUND PLANNING INFORMATION (GE SSR Study 2017-2018)

2

GENERATING PLANTS AT RISK

3

SUMMARY OF THE STUDY

4

• Crystal-Harry Allen

• Crystal-McCullough

• Harry Allen-Mead

5

SINGLE-LINE OF THE GROUP “A” LINES

SUMMARY OF THE STUDY

6

EXAMPLE: WORST DISTURBANCE MITIGATED BY RAS

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TRANSMISSION PLANNING INFORMATION FUNCTIONAL DESCRIPTION (RAS LOGIC)a) To activate the RAS: If one of the group “A” lines (Harry Allen-Mead,

Harry Allen-Crystal 500 kV, or Crystal-McCullough) is out of service (i.e., status “open” of the appropriate line circuit breakers is detected) the series capacitor on the HAE line must be bypassed within 10 to 20 seconds (at least 10 sec. delay is required).

b) To return the capacitor back into service [may be performed by operator]: if all three Group “A” lines are statused “on”, the capacitor bypass should be removed by opening the capacitor “bypass breaker”. This operation should have at least 20 seconds delay after the last relevant breaker “closed” status is detected.

8

TRANSMISSION PLANNING INFORMATION FUNCTIONAL DESCRIPTION (RAS LOGIC)

c) The scheme doesn’t require an “arming” condition (i.e., it should be armed all the time).

d) To prevent extraneous operations, prior to sending any signal to the series capacitor control system, the capacitor bypass status should be checked. If the desired status is already actual, no actions should be taken. This would prevent the RAS operation when, for example, the desired action is already taken by the operator (e.g., bypassing capacitor prior to taking a line out of service).

9

Management of Planned Outages (not RAS)

A MOA (“Manual Operator Action”) will be in place directing system operator for a planned outage of a group “A” line to:

• Prior to the outage ➢de-rate the relevant WECC paths (values will be pre-set in SCADA

accordingly);

• After implementing the outage ➢Validate that RAS operated & bypassed the HAE series capacitor.

NVE is also considering to allow the system operator to manually bypass the capacitor prior to the outage, which would result in no “bypass” signal from the RAS after the outage.

10

RAS FAILURE AND REDUNDANCY

• All single elements of the RAS will be redundant.

• If RAS fails to operate despite a valid pre-defined system condition (one of the group “A” lines is open), the operator will receive an alarm and shall perform manually:

a. If the capacitor is not bypassed by a TSR aux” signal (see next slide) try to bypass the capacitor as soon as possible.

b. If “a” is not successful, open HAE line.

11

SUPPLEMENTAL SSR PROTECTION, NON-RAS: “Line/aux” Procedure

a) All 15 turbine-generators at risk (10-CTs & 5-STs) will be equipped with TSRs (“torsional stress” protection relays).

b) An “auxiliary” SSR oscillation trip will be set for each TSR at a value below the “unit trip threshold” (approximately half unit trip time).

b) If the condition is detected by any TSR, a bypass signal will be sent to the HAE series capacitor.

12

COORDINATION WITH SSR RAS AT CRYSTAL

• Existing “Crystal SSR RAS”: Bypasses Crystal series capacitor (of Crystal - Navajo 525kV line) if both Crystal-McCullough and H. Allen- Mead 525kV lines are out of service.

• The RAS will remain in service post-HAE project; planning studies demonstrated no negative effects if both RAS operate.

• CRY-SSR RAS & HAE-SSR RAS will share line status of Crystal-McCullough and H. Allen-Mead lines for Bypass logic.

• Since HAE SSR RAS operates for outage of any of the above two lines + Crystal-H. Allen (after 12 seconds pickup delay), the RAS coordination is being discussed.

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COORDINATION WITH SSR RAS AT CRYSTAL (cont.)

• There are two situation where both RAS can operate within a 12 second time frame.

• If Crystal-McCullough goes out of service, HAE SSR will start 12 seconds timer and bypass HAE midline capacitor. If during that 12 seconds window, H. Allen-Mead goes out of service, existing SSR RAS will bypass Crystal-Navajo capacitor.

• If H. Allen-Mead goes out of service, HAE SSR will start 12 seconds timer and bypass HAE midline capacitor. If during that 12 seconds window, Crystal- McCullough goes out of service, existing SSR RAS will bypass Crystal-Navajo capacitor.

• Study shows no adverse effect from both RAS operating within 12 second time period.

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RAS CLASSIFICATION

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❑Violations of Table 1, LAPS/WAPS System Performance Criteria Outside a Transmission Operator Area• Yes

❑Maximum load loss of ≥ 300 MW for no RAS action?• No

❑Maximum generation loss ≥ 1000 MW for no RAS action?• Yes

❑Conclusion• This RAS is a Wide Area Protection Scheme (WAPS)

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• Redundant primary and backup systems

• Primary Action

• Close bypass breaker for Eldorado – Harry Allen 525kV midline capacitor.

• Backup Action

• Trip Eldorado – Harry Allen 525kV line if bypass breaker fails to close.

• RAS failure is a non-credible event

• Failure of a single component, element, or system will not effect successful operation of the RAS

RAS DESIGN – PHILOSOPHY AND CRITERIA

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RAS DESIGN – COMMUNICATIONS

System 1

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RAS DESIGN – COMMUNICATIONS

System 2

RAS DESIGN – COMMUNICATIONSHarry Allen 500kV

Multiplexer strings

Relay

C3794 /Serial

Telecom Mux

Relay

C3794 /Serial

Relay

C3794 /Serial

Relay

C3794 /Serial

Legend

Fiber Optic

Microwave Radio

Primary Path

Telecom provides two diverse geographical paths for each RAS system.

Telecom has multiple options for communication paths.NVEnergy owns and maintains the circuits and communication paths.

Telecom Mux

Telecom MuxTelecom Mux

Eldorado 500kVCRYSTAL FSCHA 500kV

Telecom Mux

Diverse Path

Eldorado 500kV

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RAS DESIGN – COMMUNICATIONSHarry Allen 500kV

Multiplexers string

Relay

C3794 /Serial

Telecom Mux

Relay

C3794 /Serial

Relay

C3794 /Serial

Relay

C3794 /Serial

Legend

Fiber Optic

Microwave Radio

Primary Path

Telecom provides two diverse geographical paths for each RAS system.

Telecom has multiple options for communication paths.NVEnergy owns and maintains the circuits and communication paths.

Telecom Mux

Telecom MuxTelecom Mux

MEAD 500kVHarry Allen 500kV

Diverse Path

MEAD 500kV

20

RAS DESIGN – COMMUNICATIONSCRY S

Multiplexers string

Relay

C3794 /Serial

Telecom Mux

Relay

C3794 /Serial

Relay

C3794 /Serial

Relay

C3794 /Serial

Legend

Fiber Optic

Microwave Radio

Primary Path

Telecom provides two diverse geographical paths for each RAS system.

Telecom has multiple options for communication paths.NVEnergy owns and maintains the circuits and communication paths.

Telecom Mux

Telecom MuxTelecom Mux

MCC 500kVCRY S

Diverse Path

MCC 500kV

21

RAS DESIGN – COMMUNICATIONSCRY N

Multiplexer strings

Relay

C3794 /Serial

Telecom Mux

Relay

C3794 /Serial

Legend

Fiber Optic

Microwave Radio

Primary Path

Telecom provides two diverse geographical paths for each RAS system.

Telecom has multiple options for communication paths.NVEnergy owns and maintains the circuits and communication paths.

Telecom Mux

Diverse Path

HA 500kV

CRY NMultiplexer strings

Relay

C3794 /Serial

Telecom Mux

Relay

C3794 /Serial

Telecom Mux

HA 500kV

22

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RAS DESIGN – LOGIC

CRY-HA Line Status52A line in service

HA-MD Line Status 52A line in service

10sec PU12sec pickup CLOSE/BFI

Series capacitor bypass bkr6 cycledropout

CRY-MC Line Status52B line OOS

ED-HA Line Status52B line OOS

Series Cap Status52B BYPASS OPEN

RAS DEFEAT OFF

Trip Eldorado-Harry Allen 525kV line if bypass breaker fails to close. (Backup logic)

RAS DESIGN – LOGIC HARDWARE

Detection: 1) Monitor line status of Crystal-McCullough via redundant RFL-9745 at

McCullough terminal using diverse communication channels. Output for line status for McCullough is then wired into redundant SEL-2440 relays at Crystal. Crystal terminal line status is hard wired into same redundant SEL-2440s at Crystal.

2) Monitor line status of Eldorado-Harry Allen via redundant SEL-2440 relays at Eldorado and at Harry Allen using breaker status contacts and diverse communication channels.

3) Monitor line status of Crystal-Harry Allen via SEL-421 relay and SEL-311L relay at both Crystal and Harry Allen using diverse communication channels. Outputs from SEL-421 relay and SEL-311L programmed for line status will be wired into redundant SEL-2440 relays at Harry Allen.

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RAS DESIGN – LOGIC HARDWARE

4) Monitor line status of Harry Allen-Mead via SEL-421 relay and SEL-311L relay at both Harry Allen and Mead using diverse communication channels. Outputs from SEL-421 relay and SEL-311L programmed for line status will be wired into redundant SEL-2440 relays at Harry Allen.

• Monitor series capacitor bypass breaker status via hard wire connection to redundant SEL-2440 relays at Crystal.

• Redundant SEL-2440 relays at both Crystal and Harry Allen communicate with redundant logic processors SEL-3555 RTACs at Harry Allen.

Logic Processing and RAS Trigger- Redundant SEL-3555 RTACs

• Sequential Event Recorder (SER)

• Indications to RTU and back to SCADA

Communication Logic Processing – SEL-3555 RTACs

• Communication to Harry Allen 500kV RTU via DNP3.

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• Eliminate SSR threat to generators at Harry Allen, Apex, Silverhawk, and Chuck Lenzie identified in transmission planning commissioned studies by bypassing series capacitor between Eldorado and Harry Allen 525kV if any of Crystal-Harry Allen, Crystal-McCullough or Harry Allen-Mead 525kV lines are out of service while Eldorado-Harry Allen 525kV line is in service and the series capacitor bypass breaker is opened.

• Classified as a Wide Area Protection Scheme (WAPS)

• RAS failure is a non-credible event

• Failure of a single component, element, or system will not effect successful operation of the RAS

• Scheme is fully redundant

CONCLUSION

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• Requesting Approval of HAE SSR RAS from RASRS

CONCLUSION