Diablo Canyon Special Protection Scheme (RAS) Presentation.pdf · relay to relay com redundant fiber ring (tx & rx 64 bit) relay to relay com sys - a sys - b dcpp_ dcsps 12-2005 dpe4

1

Diablo Canyon Special

Protection Scheme (RAS)

WECC RASRS Presentation2019-01-03

• Scheme Overview

• Operation (2018-12-01)

• Initial Functional Modification

Internal

Diablo SPS Overview

Internal

WECC Database Categorization

Reporting

Party

Scheme

Name

Classification:

WAPS, LAPS,

Safety Net

(SN) or Non-

BES PS

(NBPS) (7)

Major

WECC

RAS

OPERATING

PROCEDURE

Design Objectives —

Contingencies and system

conditions for which the

scheme was designed.

Operation — The actions

taken by the scheme in

response to Disturbance

conditions.

Modeling — Information on

detection logic or relay

settings that control

operation of the scheme.

Original

In

Service

Date

PG&E

Diablo

Canyon

SPS

Safety Net NA PG&E DOO

Prevent instability at

DCPP for loss of two of

three 500kV lines (Diablo-

Gates, Diablo-Midway #1

and Diablo-Midway #2).

Trip either DCPP Unit

#1 or DCPP Unit #2

The SPS monitors the

status of the three 500 kV

lines connected to Diablo

Canyon PP, as well the

DCPP unit outputs. If two of

three 500 kV lines are lost

on contingency and the total

plant output is above a

specific threshold, the SPS

trips one of the two Diablo

Canyon PP generating

units.

2006

Scheme has been in-service for 12 years with no

operation (correct operation or incorrect operation)

Internal

Local Area Transmission

≈ 160 mi

≈ 200

mi

Internal

Diablo Canyon

500kV Breaker and ½ (8 Breakers)

Three Lines

Two Units (2450 MW Combined Gross)

MIDWAY

BUS 2

GATES

BUS 1

DIABLO

CANYON

BUS 2

742642

DIABLO - MIDWAY #2 500kV LINE


GATES - DIABLO CANYON 500kV LINE

732

722622

812 912

802 902

652 552

542

DIABLO

CANYON

BUS 1

DIABLO

CANYON

UNIT 2

632532

DIABLO

CANYON

UNIT 1

ZZY Y

ZYX Y

ZYX YX YZ Y

Z YXY

DCPP_DCSPS 10-2005

Dpe4

Internal

Planning Study

Intensive Synchronous Swings

Possible Loss of Synchronism between Plant and WECC System for:

– Single Line Trip (or Outage) in a Double Line System (Event 1)

– Double Line Trip (or Outage) in a Three Line System (Event 2)

– Delayed Clearing Faults (Breaker Failure) (Event 3)

Internal

Planning Study (Original)

Possible Consequences of Swings

Loss of Plant (DUO) caused by:

– Plant Out-of-Step relay operation– Reactor Coolant Pump (RCP) Undervoltage

protection (delayed clearing faults cause motor stall)

Violation of NERC/WECC Planning Standard for Voltage Dips

Internal

Planning Study (Original)

Consequences of Swings and/or Separation

▪ Could Impose significant stress on WECC – Increase dependence on the adequate performance of protecting and regulating devices throughout the system.

▪ Introduce the possibility of a cascading affect.

▪ A loss of 2450 MW may cause a definite strain on the remaining generating resources.

Internal

Scheme Considerations

▪ Pulsing generator voltages upward immediately after a critical disturbance with full utilization of generator short-term overloading capabilities.

▪ Turbine main and intercept valve fast closing, initiated by an advanced overspeed control or by a disturbance detecting device.

▪ Tripping one generator immediately after indication of a critical disturbance.

– It was found that only the third measure is effective enough in the whole range of DCPP generation for the first swing suppression.

A loss of one unit does not affect WECC stability.

Internal

Solution

Diablo Canyon Special Protection Scheme

▪ Provides measures for preventing a loss of two DCPP

units on line/BF trips and unexpected Line Outages

▪ Results in preventing system instabilities on a loss of

two DCPP units.

Instability prevented by intentional tripping of one

Diablo Canyon Unit.

Internal

Instability Conditions

500kV line faults may cause dynamic instability, if

DCPP generates:

▪ above MWL1 for single line trips in a 2-line scheme (1808 MW)

▪ above MWL2 for double line trips in a 3-line scheme (1790 MW)

▪ above MWL3 for delayed clearing (12 cycles) AND V1 < .4 pu (1723

MW)

Post-transient stability – Double Line outage: ▪ DCPP output should be limited to L5 MW if dynamic stability is not

lost (O-23).

Scheme must issue trip within 70msec of line trips

and within 3 seconds for line outages

Internal

Unit Trip Effectiveness (Event 2)

No fault and 3 second delayed generator trip

( DCPP generator)

DCPP - 2,450 MW with 0.975 p.u. terminal voltage

3ph. fault and immediate generator trip

3ph. fault without remedial actions

Internal

System Throughput Time

Event Detection &

Transient suppression

20 msec

Data Communication 12-16 msec

Logic Execution 2 msec

Trip Decision Transmission 12-16 msec

System Coordination time 12-16 msec

Contact Output Time 4 msec

Total Throughput

Calculated Delay

62-74 msec

Internal

Overview of Events

System Protection (dpe4)2018-12-20 Rev 01

• DCSPS Events Categories 1 and 2: Line Outages

• DCSPS Event Category 3: Breaker Failure at Diablo

Internal

DCSPS Clearing Time for Second 500kV Loss

Due To Fault (Present Scheme Configuration)

Internal

DCSPS Clearing Time for BF Event (Present

Scheme Configuration)

Internal

500kV Line Outage Detection

The scheme is implemented only at Diablo 500kV and the

contingency detection part of the scheme monitors the “outage”

condition of the three 500kV export lines leaving Diablo. Each line

and has three outage detection methods. The three outage

detection methods, combined together, result in determination of a

Line Outage (“OR” of the following conditions) –

1. Protection Trip bus detection (does not sense manual opening of the

CB’s). This “pre-determines” a line outage 2-3 cycles before the

breakers open.

2. Local Outage Detection – Undercurrent and Breaker seals determine a

line outage (invoked for manual opening of the line CB’s.

3. Remote Outage Detection – Undercurrent monitored only at Diablo, and

has a time delay (1-second). This element is only enabled when the

aggregate plant output exceeds the reaches the minimal scheme arming

point (1720 MW).

Setting: 219 Amps

Internal

500kV Line Charging Currents (Actual Measured)

Internal

Trip Category Detection

DCSPS Event Definition

1

One Line Trip or One Line Outage in a Double line configuration (Two Lines Initially In-Service):

Twelve (12) Permutations:

OUTAGE (1st Line) → TRIP (2nd Line)

OUTAGE (1st Line) → OUTAGE (2nd Line)

Diablo – Gates 500kV Line Outage

Protection Trip (or Outage) of the Diablo Canyon – Midway #3 500kV line.

(Two Permutations)


(Two Permutations)

Diablo – Midway #3 500kV Line Outage


(Two Permutations)

Protection Trip (or Outage) of the Diablo Canyon – Gates 500kV line. (Two

Permutations)

Diablo – Midway #2 500kV Line Outage

Protection Trip (or Outage) of the Diablo Canyon – Gates 500kV line. (Two

Permutations)


(Two Permutations)

Internal



2

Double Line Trips or Double Line Outages in a Triple line configuration (Three Lines initially In-Service)

Twelve (12) Permutations:

TRIP (1st Line) → TRIP (2nd Line)

TRIP (1st Line) → OUTAGE (2nd Line)

A. Protection Trip (or Outage) of the Diablo Canyon – Gates 500kV line

AND a Protection Trip (or Outage) of the Diablo Canyon – Midway #3

500kV line within the TSIMULTANEOUS time window. (Four

Permutations)

B. Protection Trip (or Outage) of the Diablo Canyon – Midway #3 500kV

line AND a Protection Trip (or Outage) of the Diablo Canyon – Midway

#2 500kVline within the TSIMULTANEOUS time window. (Four

Permutations)

C. Protection Trip (or Outage) of the Diablo Canyon – Midway #2 500kV

line AND a Protection trip (or Outage) of the Diablo Canyon – Gates

500kV line within the TSIMULTANEOUS time window. (Four

Permutations)

Internal



3

500kV Circuit Breaker Failure

Four (4) Distinct Possibilities:

CB 622 Failure

CB 722 Failure

CB 532 Failure (Not Required)


CB 732 Failure



CB 742 Failure

Internal

1. All devices in the DCPP system are time synchronized either via IRIG-B Security (DC Shift

not Amplitude Modulated)

2. Power level transition (up or down) is 10 seconds

3. “Simultaneous” Trip is 10 Seconds

4. Dependability

1. Redundancy (in the form of “Duplication”)

2. Limit Single Points of Failure

3. Trip Coil 1 and Trip Coil 2

5. Security

1. Operation of either system will lock-out both systems

2. Input recognition time: 4 to 16ms (depending on input type)

3. Input sensitivity: 84 volts on a nominal 125VDC battery system.

4. Issue trip only when beneficial (System Topology Supervision)

5. A Line “Trip” is recognized when:

1. All Three trip signals on both breakers indicate a “Trip”

2. Three trip on one breaker with the adjacent CB in the Open/Maint. State

6. System A and B error detection comparison

7. Based on the existing arming levels, If either unit is off-line, the scheme will be

disarmed.

8. Scheme is Cut-Out during scheduled unit outages

9. A Voltage Failure alarm is provided

10. Two Trip contacts in series

DCSPS General Requirements2

2

Internal

6. The DCSPS will issue a Unit Trip when:

1. System A and System B decide to trip the same unit

2. Either system decides to trip and the other system has no trip decision within

16ms

1. Ex: Sys A is armed and Sys B is unarmed due to different power level

measurements

3. One System decides to trip and the other system has a critical error

7. If System A indicates one unit trip and System B indicates the other unit trip, NO

trip is issued.

8. A Line “Trip” is recognized when:

1. All 3-Phase trip signals on both breakers indicate “trip”

2. Three trip on one breaker with the adjacent breaker in the Open/Maintenance

state

Fail Safe Logic

Internal

Single Line and Meter Diagram

MIDWAY

BUS 2

GATES

BUS 1

DIABLO

CANYON

BUS 2

742642


537DCSPS-B


537DCSPS-A


732

722622

812 912

802 902

652 552

542

DIABLO

CANYON

BUS 1

DIABLO

CANYON

UNIT 2

632532

DIABLO

CANYON

UNIT 1

SYS - A GE UR-N60: Place in LFDC CURRENT CIRCUIT

SYS - B GE UR-N60: Place in PLS CURRENT CIRCUIT

ZZY Y

ZYX Y

ZYX YX YZ Y

Z YXY

537/511DCSPSA-1537/511DCSPSA-2

537/511DCSPSB-2 537/511DCSPSB-1

578/586DCSPSA-1578/586DCSPSA-2

578/586DCSPSB-1578/586DCSPSB-2

SYS-A

F1: DIABLO-GATES

M1: DIABLO-MID #3

M5: DIABLO-MID #2

SYS-B

F1: DIABLO-MID #2

M1: DIABLO-MID #3

M5: DIABLO-GATES

RELAY CONFIG AS

VIEWED FROM

BEHIND PANEL

UNIT #2 DCSPS RACK 3

RELAY CONFIG AS

VIEWED FROM

BEHIND PANEL


RELAY CONFIG AS

VIEWED FROM

BEHIND PANEL

LINES DCSPS RACK 1

DCPP_DCSPS 12-2005

Dpe4

Internal

Direct Communication and Panel Layout

RX

TX

W7IC

1

TX

RX

C

2

RX

TX

W7IC

1

RX

TX

C

2

RX

TX

W7IC

1

RX

TX

C

2

RX

TX

W7IC

1

RX

TX

C

2

REDUNDANT

FIBER RING (TX &

RX 64 Bit)

RELAY TO RELAY

COM

REDUNDANT

FIBER RING (TX &

RX 64 Bit)

RELAY TO RELAY

COM

SYS - A

SYS - B

DCPP_DCSPS 12-2005

Dpe4

RX

TX

W7IC

1

TX

RX

C

2

RELAY CONFIG AS

VIEWED FROM

BEHIND PANEL

UNIT #2 DCSPS RACK 3RELAY CONFIG AS

VIEWED FROM

BEHIND PANEL


RELAY CONFIG AS

VIEWED FROM

BEHIND PANEL

LINES DCSPS RACK 1

RX

TX

W7IC

1

TX

RX

C

2

RX

TX

W7IC

1

RX

TX

C

2

RX

TX

W7IC

1

RX

TX

C

2

RX

TX

W7IC

1

RX

TX

C

2

RX

TX

W7IC

1

TX

RX

C

2

578/586DCSPSA-1

DD 3

578/586DCSPSA-2

DD 4

537/511DCSPSA-1

DD 1

537/511DCSPSA-2

DD 2

537DCSPS-A

DD 5

578/586DCSPSB-1

DD 3

578/586DCSPSB-2

DD 4

537/511DCSPSB-1

DD 1

537/511DCSPSB-2

DD 2

537DCSPS-B

DD 5

Internal

CB Trip Detection and CB Fail Detection

BF

(A)

BF

(B)

BF

(C)

DSPS

SYS A

DSPS

SYS B

BF DC (-)

BF DC (+)

Protection Relay

Breaker Fail init

DCSPS BFI

UNIT CB’s

CB

BREAKER

FAIL RELAY

TIMER

TD-5

BREAKER

FAIL RELAY

TIMER

AR TRIPPING

RELAYS

DSPS

SYS A

DSPS

SYS B

TCO

RCO

DCPP_DCSPS 10-2005

Dpe4

Internal

Events 2a, 2a, 1d

0 = Open

1 = Closed

N = No Action

U1 = Trip Unit 1

U2 = Trip Unit 2

E = Either (Unit Selector Sw)

Internal

Event 1 and 2

BUS 2

742642

732

722622

542

BUS 1

632532

DIABLO - MIDWAY #2

500kV LINE

DIABLO - MIDWAY #3

500kV LINE

GATES - DIABLO

500kV LINE

DIABLO

UNIT 2

DIABLO

UNIT 1

BUS 2

742642

732

722622

542

BUS 1

632532

DIABLO - MIDWAY #2

500kV LINE

DIABLO - MIDWAY #3

500kV LINE

GATES - DIABLO

500kV LINE

DIABLO

UNIT 2

DIABLO

UNIT 1

BUS 2

742642

732

722622

542

BUS 1

632532

DIABLO - MIDWAY #2

500kV LINE

DIABLO - MIDWAY #3

500kV LINE

GATES - DIABLO

500kV LINE

DIABLO

UNIT 2

DIABLO

UNIT 1

DCSPS EVE-1A

DCSPS EVE-1D

DCSPS EVE-1C

DCSPS EVE-1F

DCSPS EVE-1B

DCSPS EVE-1E

DIABLO - MIDWAY #3 LINE OUTAGEDIABLO - MIDWAY #2 LINE TRIP

DIABLO - GATES LINE OUTAGEDIABLO - MIDWAY #2 LINE TRIP

DIABLO - GATES LINE OUTAGEDIABLO - MIDWAY #3 LINE TRIP

DIABLO - GATES LINE TRIPDIABLO - MIDWAY #3 LINE OUTAGE

DIABLO - MIDWAY #3 LINE TRIPDIABLO - MIDWAY #2 LINE OUTAGE

DIABLO - GATES LINE TRIPDIABLO - MIDWAY #2 LINE OUTAGE

DIABLO - MIDWAY #3 LINE TRIP or OUTAGEDIABLO - MIDWAY #2 LINE TRIP or OUTAGE

DIABLO - MIDWAY #2 LINE TRIP or OUTAGEDIABLO - GATES LINE TRIP or OUTAGE

DIABLO - GATES LINE TRIP or OUTAGEDIABLO - MIDWAY #3 LINE TRIP or OUTAGE

DCSPS EVE-2B DCSPS EVE-2CDCSPS EVE-2A

DCPP_DCSPS 10-2005

Dpe4

For DCSPS Event 2x, the breakers at Diablo on the linethat is OUT may not be open (Remote Open Detection).The Remote End breakers, instead, may be open. Thefigure above is equivalent to the remote end breakersOpen.

Diablo - Midway #2 Line is the only export Path

By inspection, Unit 2 will never be tripped in thiscondition.

DCSPS Trips UNIT #1, (if MW and VOLTAGEsupervision is satisfied), AND only if CB’s 532, 542,and 642 are closed. (742 position status is not relevant)(DCSPS will be restricted from tripping unless theconfiguration of the four breakers that are unaffected bythe event are in a configuration such that DCSPS willresult in a beneficial action. )

DCSPS Event - 1x and 2x: Unit Trip Selection as a function of BUS CONFIGURATIONN

OT

ES


Diablo - Gates Line is the only export Path

By inspection, Either Unit #1 or Unit #2 can be tripped.

DCSPS Trips by the Unit Selector Switch Preference, (ifMW and VOLTAGE supervision is satisfied), AND onlyif CB’s 532, 542, and 622 are closed. (722 position statusis not relevant)(DCSPS will be restricted from tripping unless theconfiguration of the four breakers that are unaffected bythe event are in a configuration such that DCSPS willresult in a beneficial action. )


Diablo - Midway #3 Line is the only export Path

By inspection, Unit 1 will never be tripped in thiscondition.

DCSPS Trips UNIT #2, (if MW and VOLTAGEsupervision is satisfied), AND only if CB’s 532, 542,and 632 are closed. (732 position status is not relevant)(DCSPS will be restricted from tripping unless theconfiguration of the four breakers that are unaffected bythe event are in a configuration such that DCSPS willresult in a beneficial action. )

UN

IT T

RIP

DE

CIS

ION

AS

A

FU

NC

TIO

N O

F R

EM

AIN

ING

50

0k

V B

RE

AK

ER

CO

NF

IGU

RA

TIO

N

BU

S C

ON

FIG

UR

AT

ION

AS

A

FU

NC

TIO

N O

F T

HE

EV

EN

T

N

N

N

N

N

N

N

N

U1

N

N

N

N

N

N

00 01 11 10

00

01

11

10

N

N

N

N

N

N

N

N

U2

N

N

N

N

N

N

N N N N

N N N N

N N E N

N N E N

00 01 11 10

00

01

11

10

00 01 11 10

00

01

11

10

622 532

722 542632 532

732 542642 532

742 542

U1 U2

1: CB is Closed at the time of Initiating Event (t0) 0: CB is Opened at the time of Initiating Event (t

0)

Diablo SPS will only trip if it results in a benefit. (Removal of one of two units that remain tied to the system after the initiating event.

U1: Unit #1 Tripped U2: Unit #2 Tripped E: Either - Unit Tripped based on Unit Selector Sw

Internal

Events 1 and 2 Implemented Logic

AND

CB 532 CLOSED

CB 542 CLOSED

CB 642 CLOSED

OR

AND

AND

AND

DG OUTAGE

DM#3 TRIP

DM#3 OUTAGE

DG TRIP

DM#3 (OUTAGE or TRIP)

DG (OUTAGE or TRIP)AND

UNIT #1 TRIP

AND

CB 532 CLOSED

CB 542 CLOSED

CB 622 CLOSED

OR

AND

AND

AND

DM#2 OUTAGE

DM#3 TRIP

DM#3 OUTAGE

DM#2 TRIP


DM#2 (OUTAGE or TRIP)AND

UNIT TRIP BY UNITSELECTOR

AND

CB 532 CLOSED

CB 542 CLOSED

CB 632 CLOSED

OR

AND

AND

AND

DG OUTAGE

DM#2 TRIP

DM#2 OUTAGE

DG TRIP


DG (OUTAGE or TRIP)AND

UNIT #2 TRIP

DCSPS EVE-1A

DCSPS EVE-1D

DCSPS EVE-1C

DCSPS EVE-1F

DCSPS EVE-1B

DCSPS EVE-1E

DCSPS EVE-2B

DCSPS EVE-2C

DCSPS EVE-2A

TRIP LOGIC DCSPS Event - 1x and 2x (SEE STATE TRANSITION DIAGRAMS)

Physical Topology ofthe 500kV Bus

(From Karnaugh Map)


(From Karnaugh Map)


(From Karnaugh Map)

DCPP_DCSPS 12-2005

Dpe4

Internal

Event 3

632

742

BUS 2

742642

732

722622

542

BUS 1

632532

DIABLO - MIDWAY #2

500kV LINE

DIABLO - MIDWAY #3

500kV LINE

GATES - DIABLO

500kV LINE

DIABLO

UNIT 2

DIABLO

UNIT 1

FAILBUS 2

642

BUS 1

632

DIABLO - MIDWAY #2

500kV LINE

DIABLO - MIDWAY #3

500kV LINE

GATES - DIABLO

500kV LINE

DIABLO

UNIT 2

DIABLO

UNIT 1

722

FAIL

622

732532

542 742

BUS 2

642

DIABLO - MIDWAY #2

500kV LINE

DIABLO - MIDWAY #3

500kV LINE

GATES - DIABLO

500kV LINE

DIABLO

UNIT 1

FAIL

532

542

BUS 1

722

732

622

DIABLO

UNIT 2

BUS 2

DIABLO - MIDWAY #2

500kV LINE

DIABLO - MIDWAY #3

500kV LINE

GATES - DIABLO

500kV LINE

DIABLO

UNIT 1

532

542

722622

DIABLO

UNIT 2

732632

642

FAIL

742

DCSPS Event - 3x: Unit Trip Selection as a function of BUS CONFIGURATION

DCSPS EVE-3ACB 622 Failure

DCSPS EVE-3BCB 722 Failure

BUS 1

DCSPS EVE-3ECB 732 Failure

DCSPS EVE-3HCB 742 Failure

BU

S C

ON

FIG

UR

AT

ION

AS

A

FU

NC

TIO

N O

F T

HE

EV

EN

T

N

N

N

N

N

N

N

N

E

N

N

N

N

00 01 11 10

00

01

11

10

732 632

742 642

E

E

E

UN

IT T

RIP

DE

CIS

ION

AS

A

FU

NC

TIO

N O

F R

EM

AIN

ING

50

0k

V B

RE

AK

ER

CO

NF

IGU

RA

TIO

N

Diablo - Midway #2 or #3 Lines can be anexport Path (Depending on Initial Busconfiguration)

Given the proper initial bus configuration,Either Unit Can be tripped.

DCSPS Trips by the Unit Selector Switch, (ifMW and VOLTAGE supervision is satisfied),AND only if CB’s 632, 642, are closed. (732and 742 Position is not relevant)

N

N

N

N

N

N

N

E

N

N

N

00 01 11 10

00

01

11

10

632 532

642 542

EE E

U1

U2

N

N

N

N

N

N

N

N

N

N

00 01 11 10

00

01

11

10

622 532

642 542

U1

U1

N N U1 U1

N

N

N

N

N

N

N

N

N

N

00 01 11 10

00

01

11

10

622 532

632 542

U2

U2

N NU2 U2

Diablo - Midway #2 or #3 Lines can be anexport Path (Depending on Initial Busconfiguration)

Given the proper initial bus configuration,Either Unit can be tripped (Provided the MWand VOLTAGE supervision are satisfied):

DCSPS Trips by the Unit Selector Switch, IfCB 632 and CB 642 are closed. (CB 532 and542 position status is not relevant)

DCSPS Trips UNIT #1, If CB’s 532, 542, and642 are closed AND 632 is opened.

DCSPS Trips UNIT #2, If CB’s 532, 542, and632 are closed AND 642 is opened.

NO

TE

S

Diablo - Midway #2 or Diablo - Gates Linescan be an export Path (Depending on InitialBus configuration)

Given the proper initial bus configuration,Only Unit 1 will be tripped.

DCSPS Trips UNIT #1 For (3) Conditions(Provided the MW and VOLTAGEsupervision are satisfied):

If CB’s 532, 542, and 642 are closed (CB 622position status is not relevant).



DCPP_DCSPS 10-2005

Dpe4

1: CB is Closed at the time of Initiating Event (t0) 0: CB is Opened at the time of Initiating Event (t

0)

Diablo SPS will only trip if it results in a benefit. (Removal of one of two units that remain tied to the system after the initiating event.

U1: Unit #1 Tripped U2: Unit #2 Tripped E: Either - Unit Tripped based on Unit Selector Sw

Diablo - Midway #3 or Diablo - Gates Linescan be an export Path (Depending on InitialBus configuration)

Given the proper initial bus configuration,Only Unit 2 will be tripped.

DCSPS Trips UNIT #2 For (3) Conditions(Provided the MW and VOLTAGEsupervision are satisfied):




Internal

Events 3 Implemented Logic

AND

CB 632 CLOSED

CB 642 CLOSED

ANDCB 622 Fail


AND

CB 542 CLOSED

AND

CB 632 CLOSED

CB 642 CLOSED

TRIP LOGIC DCSPS Event - 3x (SEE STATE TRANSITION DIAGRAMS)


(From Karnaugh Map)

PhysicalTopology of

the 500kV Bus (From

KarnaughMap)

DCSPS EVE-3A

CB 642 CLOSED

AND

CB 542 CLOSED

CB 632 CLOSED

AND

CB 632 OPENED

CB 642 OPENED

CB 532 CLOSED

CB 532 CLOSEDAND


UNIT #1 TRIP

ANDUNIT #2 TRIP

CB 722 FailDCSPS EVE-3B

OR

AND

CB 532 CLOSED

CB 542 CLOSED

CB 642 CLOSED

AND

CB 532 CLOSED

CB 542 CLOSED

CB 622 CLOSED

AND

CB 532 CLOSED

CB 622 CLOSED

CB 642 CLOSED

ANDCB 732 Fail

UNIT #1 TRIP

DCSPS EVE-3E

PhysicalTopology of

the 500kV Bus (From

KarnaughMap)

OR

AND

CB 532 CLOSED

CB 542 CLOSED

CB 632 CLOSED

AND

CB 532 CLOSED

CB 542 CLOSED

CB 622 CLOSED

AND

CB 542 CLOSED

CB 622 CLOSED

CB 632 CLOSED

ANDCB 742 Fail

UNIT #2 TRIP

DCSPS EVE-3H

PhysicalTopology of

the 500kV Bus (From

KarnaughMap)

DCPP_DCSPS 12-2005

Dpe4

Internal

Operator Interface

RESET

LINE OUT AT DC 2-LINES TRIP

LINE OUT / P > L1

2-LINES OUT

LINE OUT / LINE TRIP

System Unavailable

Sys DD Com Fail25

29

32

26

27

28

30

31

33

37

34

35

36

38

39

9

12

17

20

14

16

10

11

13

15

18

19

22

21

23

24

7

2

3

5

4

6

8 40

1

47

42

43

45

44

46

48

41

LINE OUT GATES

DC - GATES DC - MIDWAY #2 DC - MIDWAY #3

622 OPEN / MAINT.

722 OPEN / MAINT.

LINE TRIP ACTIVE

622 SYS A&B DISAG

722 SYS A&B DISAG

CB & UC DISAGREE

Operational Status Operational Status ALARMS

LINE TRIP / LINE OUT

BFT PLANT TRIP

UNIT #1 TRIP

UNIT #2 TRIP

LINE OUT AT DC

LINE OUT MIDWAY

642 OPEN / MAINT.

742 OPEN / MAINT.

LINE TRIP ACTIVE

642 SYS A&B DISAG

742 SYS A&B DISAG

CB & UC DISAGREE

LINE OUT AT DC

LINE OUT MIDWAY

632 OPEN / MAINT.

732 OPEN / MAINT.

LINE TRIP ACTIVE

632 SYS A&B DISAG

732 SYS A&B DISAG

CB & UC DISAGREE

622 BF

722 BF

532 BF

632 BF

732 BF

542 BF

642 BF

742 BF

ETHERNET Fail

MAINTENANCE ALARM

537DCSPS – (A or B) LED’s and Pushbuttons

Rack 1 Rack 2 Rack 3

Sys - A

Sys - B

537DCSPS-A

537DCSPS-B

Sys - A

Sys - B

Lines Rack Unit 1 Rack Unit 2 Rack

Internal

Trip Circuit

Trip Coil 1 DC (-)

Trip Coil 1 DC (+)

DCSPS Unit-1 Tripping Relays

U1

CB

TC 1

DCPP_DCSPS 01-2006

Dpe4

Cut-Out Switch

RCO/DCSPS-A

Cut-Out Switch

RCO/DCSPS-B

Trip Coil 2 DC (-)

Trip Coil 2 DC (+)

U1

CB

TC 2

Cut-Out Switch

RCO/DCSPS-A

Cut-Out Switch

RCO/DCSPS-B

OPEN

CLOSE

LATCH

SYS-A

BF DC (-)

BF DC (+)

Cut-Out Switch

RCO/DCSPS-B

Cut-Out Switch

RCO/DCSPS-A

PRI

TC-1

SYS-A

Mod-F

PRI

TC-1

SYS-B

Mod-F

OPEN

CLOSE

LATCH

SYS-B

OPEN

CLOSE

LATCH

SYS-BOPEN

CLOSE

LATCH

SYS-B

OPEN

CLOSE

LATCH

SYS-AOPEN

CLOSE

LATCH

SYS-A

BF INIT

SYS-A

SYS-B

CB

CLOSE

579H

Auto Reclose

DCSPS

TRIP COIL #1

TRIP

DCSPS

Reclose

Block

DCSPS

TRIP COIL #2

TRIP

DCSPS

Breaker Failure

Initiate

Unit #1 Sys - A Trip

Unit #1 Sys - B Trip

ORUnit #2 DCSPS

Lockout

Close

Close Close

Close

Ope

n

Unit #1 DCSPSLockout

(From U2 Trip bySys-A OR Sys-B)

SYS A RESET PB

Open Close

Clo

seSEC

TC-1

SYS-A

Mod-M

SEC

TC-1

SYS-B

Mod-M

PRI

TC-2

SYS-A

Mod-F

PRI

TC-2

SYS-B

Mod-F

SEC

TC-2

SYS-A

Mod-M

SEC

TC-2

SYS-B

Mod-M

PRI

BFI

SYS-A

Mod-F

PRI

BFI

SYS-B

Mod-F

SEC

BFI

SYS-A

Mod-M

SEC

BFI

SYS-B

Mod-M

Close

Close Close

Close

U1 Trip Lockout U1 Trip Lockout

Sys-B Reset

Close

Close

Close

Clo

se

SYS-BSYS-A SYS-BSYS-A SYS-BSYS-A

SYS B RESET PB

Sys-A Reset

Sys-B Reset

Sys-A Reset

Internal

Test Modes & Alarms

1. Design Validation & Commissioning1. System test – all conditions, all states, all transitions

2. Periodic (w/ system out of service)1. Breaker status information integrity

2. Trip circuit integrity (output contact and associated wiring)

3. BFI detection integrity

4. Aux relay integrity

3. Scheme Alarms1. System A / System B Consistency Alarm

1. Status & Decisions

2. Communication Alarms

3. Relay Alarms1. Critical – disable respective system

2. Operation alarm

4. Operator Interface1. LED

2. SCADA

3. Unit Selector Switch

4. Reset Pushbutton

Internal

Testing Document

EVE Scenario ARM LEVELS G→MW2 Test MW2→G Test G→MW3 Test MW3→G Test MW2→MW3 Test MW3→MW2 Test

UNIT SEL SW

1

LLO → TRIP

L3<MW<L1 No Trip No Trip No Trip No Trip No Trip No Trip

L1<MW U2 TRIP U2 TRIP U1 TRIP U1 TRIP

U1 TRIP U1 TRIP Unit 1 Selected


ROD → TRIP





LLO → LLO

MW<L1 & V1<Vdlos No Trip No Trip No Trip No Trip No Trip No Trip

MW>L1 & V1>Vdlos No Trip No Trip No Trip No Trip No Trip No Trip

L1<MW & V1<Vdlos U2 TRIP U2 TRIP U1 TRIP U1 TRIP



LLO → ROD






ROD → LLO






ROD → ROD






2

TRIP → TRIP Within 10 sec

MW<L3 No Trip No Trip No Trip No Trip No Trip No Trip





TRIP → LLO L3<MW<L2 No Trip No Trip No Trip No Trip No Trip No Trip

Internal

Testing Document

Internal

2018-12-01Scheme Operation

Internal

Unit #1 Ramping Down

Intake fouling followed by Coolant Pump Vibration

1h 50m

Internal

Conditions Immediately Prior to Scheme Actuation

MIDWAY

BUS 2

GATES

BUS 1

DIABLO

CANYON

BUS 2

742642




732

722622

812 912

802 902

652 552

542

DIABLO

CANYON

BUS 1

DIABLO

CANYON

UNIT 2

632532

DIABLO

CANYON

UNIT 1

ZZY Y

ZYX Y

ZYX YX YZ Y

Z YXY

DCPP_DCSPS 10-2005

Dpe4

796 Amps

1216 Amps

1603 Amps

210 Amps

210 Amps

Internal

Historical Data (2/26/2018)

Internal


Internal


Internal

PI Trend of the Event (12/1/2018)

Internal

Historical Data

Internal

Control Point Implementation & Monitoring

• The Control Point equations below will allow the Grid Control

Center to monitor the potential line flows if DCPP were to ramp

down to 1700 MW.

• Mitigation strategies considered if ROD were not removed.

Internal

Example – Risk for a Ramp Down

Internal

Example – Risk for a Ramp Up

Internal

Trend Comparison to Event Data

Internal

Logic Change

Internal

Logic Change (Relay Implementation)

Internal

Verbiage from Corresponding 5MM

1. Diablo Canyon Power Plant will be restricted to 1700 MW output under the

following conditions:

• Diablo-Gates 500kV line outage

• Diablo-Midway #2-500kV line outage

• Diablo-Midway #3-500kV line outage

• Midway #1-500kV bus outage

• Midway #2-500kV bus outage

• Any outage of Midway CB 802, 902, 912, or 812 that places the system in a

configuration where a single contingency with a breaker failure operation

would cause the open ending of both the Diablo-Midway #2 and #3 500kV

lines.

For any loss of the remote ends of the Diablo-Gates 500kV line, Diablo-Midway #2-

500kV line, and the Diablo-Midway #3-500kV line, the Grid Control Center would

deenergize the line from Diablo Canyon so that the local portion of the Diablo SPS

recognizes that the line is out of service. At the same time, Diablo Canyon will be

given the order to limit output to 1700 MW.

Internal

RASRS Approval Request

PG&E seeks approval to remove “Remote Open Detection” portion of

the logic and monitor with a control point calculation.

The scheme will be less dependable in detecting Open Ended lines.

A newly developed operating procedure covers the scenario with “Remote

Outage Detection” disabled.

PG&E requests two changes –

1. Short Term (Today): Disabling the Remote Outage detection. Cover via operating

procedure captured in a 5 Minute Meeting.

2. Longer Term (Six Months): Implement the Remote Outage detection in a more

secure manner. Place devices at the remote end of the line and implement logic

like the “local Outage detection”. Monitor with control point calculation and

documented procedure.

Documents

Diablo Canyon Special Protection Scheme (RAS) Presentation.pdf · relay to relay com redundant fiber ring (tx & rx 64 bit) relay to relay com sys - a sys - b dcpp_ dcsps 12-2005 dpe4