per-006-1 operator training noxon rapids powerhouse - per... · per-006-1 operator training •...

PER-006-1 Operator Training

Noxon Rapids Powerhouse

08.07.2019


• Purpose

– To ensure that personnel are trained on

specific topics essential to reliability to

perform or support Real-time operations of

the Bulk Electric System (BES)

– This training is essential for supporting the

Real-time operations of the BES


• Requirements and Measures

– Each Generator Operator shall provide

training to personnel on the operational

functionality of Protection Systems and

Remedial Action Schemes (RAS) that affect

the output of the generating Facilities it

operates.


• Compliance

– Enforcement

• WECC is the Regional Entity responsible for

enforcement of NERC Reliability Standards.

– Evidence Retention

• The Generator Operator shall keep data or

evidence of Requirement R1 for the current

year and three previous calendar years.


• Applicability

– To accomplish this, applicable plant personnel

responsible for Real-time control of a generating

Facility must be trained on how the operational

functionality of Protection Systems and RAS are

applied and the affects they may have on a

generating Facility.

– The Generator Operator must also ensure it provides

applicable training that results from changes to the

operational functionality of the Protection Systems

and RAS that affect the output of the generation

Facilities.


• Considerations for operational

functionality may include, but are not

limited to the following:

– Purpose of protective relays and RAS

– Zones of protection

– Protection communication systems (e.g., line

current differential, direct transfer trip, etc.)

– Voltage and current inputs

– Station dc supply associated with protective

functions

– Resulting actions – tripping/closing of

breakers; tripping of a generator step-up

(GSU) transformer; or generator

ramping/tripping control functions


• What is not included:

– Protective systems which trip breakers

serving station auxiliary loads:

• pumps

• fans

• fuel handling equipment

• secondary unit substation

• low voltage switchgear

• low voltage transformers

• relays protecting other downstream plant

electrical distribution system components


• Plant Overview

– One-Line Diagrams

– Generator Unit Control and Protection

– Generator Bus Protection

– GSU Transformer Protection


• Zones of Protection



Each zone of protection contains:• Zone Specific Protection Plan

• One or more Components of a Power System

• Usually 2 Circuit Breakers with the exception of Generator Breakers

When a Fault Occurs within a Zone:• Circuit Breakers within the Zone will Trip

• Isolating all of the Equipment within that Zone from the rest of the System

• Protection Zones typically have Primary and Pack-up Protection



• Protective relays are designed around

several Zones of Protection in order to reduce

or limit the amount of equipment that would

be taken out of service by the operation of a

relay within that Protection Zone

• A relay operation in a Protection Zone will

only isolate electrical Equipment within that

Zone, thus minimizing equipment and unit

outages to only that equipment necessary to

isolate the fault and/or failure

• Zones of Protection are overlapped to ensure

all electrical equipment is protected


• Zones of Protection at Noxon Rapids

Generator Zone of Protection

• Spans from the Generator Wye Point to

the GSU side of the Generator Circuit

Breaker (GCB)

Generator Bus Zone of Protection

• Spans from the generator

side of the GCBs to the

GSU Transformer High

Voltage Bushing CTs

GSU Transformer Zone of Protection

• Spans from the Low

Voltage side busing

CTs on the GSU

Transformer to the

High Voltage side

Bushing CTs

Protective Relays

• Purpose of protective relays - Protect electrical equipment and

limit damage during electrical faults, equipment failure and/or

abnormal operating conditions such as:

• Abnormal Frequency

• Abnormal Voltage

• Overexcitation

• Loss of Field

• Loss of Synchronism

• Inadvertent Energization

• Breaker Failure

• Loss of Prime Mover

• Blown PT Fuses

• Open Circuits / Conductors

Protective Relays for Generator Tripping


Typical Relay Flow Chart

BKR 41

BKR A

SHUTDOWN PRIME

MOVER

ALARM

BKR S BFI

51TG1

78

81 71 UAT

71

64F

60

53

49

86T351TG2 UAT

87T UAT

4694G1

86G2

86G3

86T1

86T2

50/51 UAT

87O

21 or 51V

50/27

86G1

63

63UAT

24-2

40

59GN

87G

87T

51TG2

59

24-1

32

50/51G


Typical Avista Device List

2 – Time delay relay12 – Overspeed device21 – Distance relay23 – Temperature control24 – Volts/Hertz Relay 25 – Synchronism check relay27 – Undervoltage relay30 – Annunciator relay32 – Directional power relay37 – Underpower relay40 – Field relay41 – Field circuit breaker43 – Manual transfer or selective device46 – Reverse phase or phase balance47 – Phase sequence voltage relay.49 – Machine or transformer thermal relay.



50 – Instantaneous overcurrent relay51 – Time delay overcurrent relay52 – AC circuit breaker.52/a – Circuit breaker auxiliary switch closed when the breaker is closed52/b – Circuit breaker auxiliary switch closed when the breaker is open53 – Generator exciter59 – Overvoltage relay60 – Voltage or current balance relay62 – Time delay stopping or opening relay63 – Sudden pressure relay64 – DC ground relay67 – Directional overcurrent68 – Blocking relay for power swings69 – Permissive control device



72 – DC circuit breaker74 – Alarm relay other than an Annunciator76 – DC overcurrent relay78 – Out of step relay79 – AC Reclosing relay81 – Frequency relay85 – Carrier or pilot relay86 – Lock out relay87 – Differential relay89 – Line switch90 – Regulating device94 – Auxiliary tripping relay


Typical Generator

Relay Panel


Generator Protection Panel

Device: 87G-GR1

Function: Generator Protection

SEL-300G provides generator protection for Unit 1

Zone of Protection: Generator

Trip Elements:

• 24 Volts/Hz – Alarms to PLC• 27 Under Voltage

• 40 Loss of Field

• 46 Negative Sequence – Alarm to PLC• 59 Over Voltage

• 64 Generator Stator Ground

• 87 Generator Stator Differential

Trip Action:

• 86G1

• 86GD1

Reference Drawings:

One-Line Diagram 401E-20-030-00-02

Three-Line Diagram 401E-01-031-00-01



Device: 50BF

Function: Breaker Failure

The SEL-251 provides breaker failure protection on 52G1


Trip Elements:

• 50L Phase Definitive Time Instantaneous Overcurrent• 51P Phase Time Overcurrent• 51NTD Residual Ground Time Overcurrent• 51QT Negative Sequence Definitive Time Overcurrent• 51QTD Negative Sequence Time Overcurrent

Trip Action:

• 86A• 86G1

• Keys Direct Transfer Trip (DTT) to R-331 via 67/351



Device: 86G1


86G1 provides generator lockout protection for Unit 1


Trip Elements:

• GR1• GR2

• 50BF

• Station Service A• AVR Watchdog Timer

• RAS A Output

Trip Action:

• 52G1 Trip Coil 1

• 52G1 Trip Coil 2

• AVR to Normal Stop• 4 Master Relay Block



Device: 86GD1


86GD1 provides generator lockout protection for Unit 1


Trip Elements:

• GR1• GR2

Trip Action:

• 52G1 Trip Coil 1• 52G1 Trip Coil 2

• CO2 Trip

• AVR to Normal Stop• 4 Master Relay Block



Device: 87G-GR2


SEL-300G provides redundant generator protection for Unit 1


Trip Elements:






Trip Action:

• 86G

• 86GD

Protective Relays for GSU Transformer

Typical

Transformer

Relay Panel


Transformer Protection Panel

Device: 67A

Function: Directional Overcurrent Protection

SEL-351 provides directional overcurrent protection for the 14.4kV Bus A

Zone of Protection: GSU Transformer and 14.4kV Bus

Trip Elements:

• 51 AC Inverse Time Overcurrent

• 32 Directional Power

• 67A AC Directional Overcurrent

Trip Action:

• 86A

• 86GD1• Keys Permissive Overreach Transfer Trip (POTT) and

Direct Transfer Trip (DTT) schemes with SEL-351 on R-

331 in Switchyard using Mirrored Bits.



Device: 87A

Function: Transformer Differential

The SEL-387 provides differential protection for GSU A Bank internal fault and a fault on the 14.4kV “A” Bus. Zone of

protection is from the 230kV high voltage winding to the two

generator breakers. The 4th Winding is used for Station Service Overcurrent Protection


Trip Elements:

• 87A Current Differential• 51P Phase Time Overcurrent• 51NTD Residual Ground Time Overcurrent• 51QT Negative Sequence Definitive Time Overcurrent• 51QTD Negative Sequence Time Overcurrent

Trip Action:

• 86A

• Initiates Breaker Failure for Unit 1

• Initiates Breaker Failure for Unit 2• Keys Direct Transfer Trip (DTT) to R-331 via SEL-

351(67)



Device: 86A

Function: Transformer Lockout Protection

The 86A provides redundant generator protection for Unit 1


Trip Elements:






Trip Action:

• 86A

• Initiates Breaker Failure for Unit 1 • Initiates Breaker Failure for Unit 2

• Keys Direct Transfer Trip (DTT) to R-331 via SEL-351(67)



Device: 63X

Function: Transformer Sudden Pressure Seal-in

The 63X provides transformer protection for GSU Bank A

Zone of Protection: GSU Transformer

Trip Elements:

• 63SP

Trip Action:

• 86A

Protective Relay Communication

Systems Protective Really Communication Systems are

critical to ensure remote relay operations such as:

• PTT – Permissive Transfer Trip

• DTT – Direct Transfer Trip

• Remote Synchronizing of Noxon Unit 5 at

Switchyard

Protective Relay Inputs

Instrument Transformers:• Step down system voltage (PTs) and

current (CTs) to safe levels

• Allows for Real-time inputs to

protective relay and other control

devices

Typical Generator PT Typical Generator CT

Protective Relay Inputs

Typical Switchyard PT Typical Switchyard CT

Protective Relay DC Systems

125VDC System is

critical to the operation

of all protective

devices as shown on

this typical GCB

Schematic

Remedial Action Schemes

Definition of RAS (from NERC)

• A scheme designed to detect predetermined System

conditions and automatically take corrective actions that

may include, but are not limited to:

– Curtailing or tripping generation or other sources

– Curtailing or tripping load

– Reconfiguring a System


RAS Accomplish these objectives:

• Meet Requirements Identified in the NERC Reliability

Standards

• Maintain System Stability

• Maintain Acceptable System Voltages

• Maintain Acceptable Power Flows

• Limit the Impact of Cascading

• Address other BES Reliability Concerns


• RAS at Avista

• Problem arises when we have the following conditions:

– Heavy flows on the northern 230kV transmission system

– High generation output at Cabinet Gorge and Noxon Rapids

– 230kV System Line Fault (N-1) and (N-2)

• Transmission Corridors of Concern are:

– Noxon – Bell

– Noxon – Beacon

– Noxon – Benewah

– Noxon – Hot Springs


• The Avista RAS is intended to mitigate the stability

problem caused by a system disturbance on the 230kV

grid during heavy flows out of Noxon.

• Mitigation consists of generator tripping at Noxon Rapids

Powerhouse

• A second stability problem exists for Cabinet Gorge

Powerhouse when we have high generation output and

One 230kV Line Out Of Service

• The loss of a second 230kV line (N-2) will cause the

Cabinet Gorge Generators to go unstable

• This is mitigated by dropping generation at Cabinet Gorge

to below 70MW


• Questions?

per-006-1 operator training noxon rapids powerhouse - per... · per-006-1 operator training •...

Documents