l90 complete agenda

8/19/2019 l90 Complete Agenda

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L90 Line Differential Relay

Digital Energy

Multilin

Agenda


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Introduction

1) Reliability: has two aspects:

Dependability: the degree of certainty that the relay will operate

correctly.

Security: the relay will not operate incorrectly

2) Speed: Very high power during fault conditions: delays translate intoincreased damage: faster protection tends to compromise relay system

security and selectivity.

3) Sensitivity: The minimum operating quantities allows the relay to detect

an abnormal condition. High-impedance ground faults,voltage unbalance

and high source- to- line impedance ratio affect the sensitivity

4) Selectivity : or coordination: ability of the relay system to minimize

outages as a result of a fault by operating as fast as possible within their

primary zone.

5) Simplicity and ergonomics: simple to apply and to obtain maximum

protection for the minimum cost in one box

Terms: Coordination, Unit Protection/None Unit Protection, Primary/Back up

Transmission Line Protection Considerations

High voltage transmission lines have extremely high level of fault current and

low impedance characteristics. Over current protection can not be as fast as it’s

needed.

Solutions:

• Current Differential:

• Unit Protection

Measure the current phasors at both ends of the line. If you have a line fault

there will be a difference in the current magnitude at each end and/or a changein current phase angle with respect to applied voltage.

• Distance or (Impedance):

• None Unit Protection

Impedance known as Distance: The distance relay operates by using bothvoltage and current to determine if a fault is in a relay’s zone of protection. At

time of fault Current increases and voltage decreases which translates into a

change in impedance.

Introduction

Transmission Line Protection Considerations


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L90 Current Differential Relay:

• Protection:

– Segregated Line current differential (87L)

– 87L Trip logic

– Phase/Neutral/Ground TOCs

– Phase/Neutral/Ground IOCs

– Negative sequence TOC

– Negative sequence IOC

– Phase directional OCs

– Neutral and negative sequence directional OC – Phase under- and overvoltage

– 3-zone distance back-up with power swing detect,load encroachment, POTT and line pickup

Features


• Control:

– Breaker Failure (phase/neutral amps)

– Synchrocheck & Autoreclosure

– Direct messaging (8 extra inter-relay DTT bits exchanged)

• UR Metering:

– Fault Locator

– Oscillography

– Event Recorder

– Data Logger

– Phasors / true RMS / active, reactive and apparent power, powerfactor

• 87L Metering:

– actual differential current

– local and remote phasors

– communication channel status

Features


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Features

831706AS.CDR

L90 Line Differential Relay

52

Monitoring CLOSE TRIP

Data From/To Remote End(via Dedicated Communications) MeteringFlexElement

TM Transducer Inputs

50DD 51N(2)50N(2)67P(2)87L 21P 68 7850BF(2)51_2(2)51P(2)50_2(2)

79

50P(2) 21G67N/G

27P(2)

27X

59N

59X

59P

25(2)

3V_0

51G(2)50G(2)


Line Current Differential

• Improved operation of the line current di fferential (87L)element:

– Dynamic Restraint increasing security without jeopardizingsensitivity

– Line Charging Current Compensation to increase sensitivity

– Self-synchronization

– Channel Asymmetry Compensation to compensate forasymmetrical channel delay on multiplexed channels

– CT Saturation Detection

– Zero sequence current removal for applications on lines witha tapped transformers with a primary wye neutral grounded.

– Relay ID for secure applications on higher ordercommunication systems.


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Line Current Differential

L90 can be appliedon bo th 2-terminaland 3-terminalapllications:hardware andfirmware are thesame.

Direct point-to-point Fiber

(up to 100Km)

ORVia SONET system telecom multiplexer

(GE’s FSC)

FSC

(SONET)

FSC

(SONET)

(64Kbps)

(155Mbps)

- G.703

- RS422

- G.703

- RS422


Installation


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FIBER - LED & ELED

TRANSMITTERS

The above figure shows the 2-Terminal

configuration for the 7A, 7B, & 7C fiber-

only modules.

LASER FIBER MODULES

WARNING: When using a 1300/1550 nm

LASER Interface, attenuators may be

necessary to ensure that you do not exceed

Maximum Optical Input Power (-14 dBm) to

the receiver.

DIRECT FIBER


Installation

DIRECT FIBER


Installation


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DIRECT FIBER OPTICAL POWER BUDGET


Installation

Typical pin interconnection between two G.703 interfaces back-to-

back.

G.703 CO-DIRECTIONAL INTERFACE


Installation


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G.703 INTERFACE

G.703 module dip switches..


Installation

G.703 INTERFACE

Connection to higher order system

G.703 Timing Selection


Installation


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G.703 INTERFACE

Minimum Remote Loopback Test mode data processing


Installation

G.703 INTERFACE

Dual Loopback Test mode data processing


Installation


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Back to Back: Correct

Internal Timing mode

(S1=Off, S5=On, S6=Off)

Back to Back : Will work but not ideal.

G.703 INTERFACE

Loop Timing mode

(S1=Off, S5=Off, S6=Off)

Internal Timing mode

(S1=Off, S5=On, S6=Off)

Loop Timing mode (factory

default for connections to

higher order system

(S1=On, S5=Off, S6=Off)


Installation

Point to Point using Modems (for example RAD modem):

• Octet Timing

Disabled

• Loop Timing

mode

• Octet Timing

Disabled

•Internal

Loop Timing

mode

Loop Timing

mode

Rad Modem Rad Modem

Only one clock per system

generated by right L90.

G.703 INTERFACE


Installation


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Connection via multiplexers (higher order system):

The multiplexer provides the clock for all relays: again, one clock per

system:

Multiplexer Multiplexer • Octet Timingenabled

• Loop Timing

mode

• Octet Timing

enabled

• Loop Timing

mode

G.703 INTERFACE


Installation

Typical pin interconnection between two RS422 interfaces

RS.422 INTERFACE


Installation


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WARNING: When using a 1300 nm LASER Interface, attenuators may be

necessary to ensure that you do not exceed Maximum Optical Input Power

(-14 dBm) to the receiver.

RS422 & FIBER INTERFACE CONFIGURATION

MIXED INTERFACES


Installation

The IEEE C37.94 Standard defines a point to point opt ical link for

synchronous data between a multiplexer and a teleprotection

device. Designed to interface with IEEE C37.94 compliant digital multiplexer

and/or an IEEE C37.94 compliant interface converter for use wi thL90.

IEEE fiber C37.94 INTERFACE


Installation

Connected directly to

MUX

Connected to MUX

via converter


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For the Internal Timing Mode, the system clock is generatedinternally; therefore, the timing switch selection should be Internal

Timing for Relay 1 and Loop Timed for Relay 2. There must be only

one timing source configured. For the Looped Timing Mode, the system clock is derived from the

received line signal; therefore, the timing selection should be inLoop Timing Mode for connections to h igher order systems.

IEEE fiber C37.94 INTERFACE


Installation

G7X

G7R

Transmitted

data blocked

Local Loopback Test Mode

Local relay

COMMS CHANNEL TESTING


Installation


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G7X

G7R

Received data

echoed back.Remote Loopback Test

Local relay

COMMS CHANNEL TESTING

G7X

G7R

Remote

relay


Installation

COMMS CHANNEL ON-LINE DIAGNOSTICS

Current comms status is available

in Actual Values.History of comms di sturbances is l ogged

into event recorder .


Installation


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Installation

MAJOR COMMS ALARMS

1. 87L DIFF CH1/2 FAIL

2. 87L DIFF PFLL FAIL

3. 87L DIFF CH1/2 ID FAIL

87L DIFF BLOCKED

MINOR COMMS ALARMS

1. 87L DIFF CH1/2 CRCFAIL

2. 87L DIFF CH1/2 LOSTPKT

3. 87L DIFF TIME CHANGED

4. 87L DIFF ASYM DETECTED

5. 87L DIFF 1/2 ASYM MAX

6. 87L DIFF GPS1/2 FAIL


CHANNEL ID FAIL

1. Each packet carries relay

ID number per channel

2. Each received packet is

compared with ID

programmed L90 PowerSystem menu.

3. “0” means NO Channel ID

check is required (for

direct fibers).


Installation

Protection against:

1. Inadvertent loopback

2. Inadvertent connection to awrong L90 relay.


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Percent Current Differential

L90 Current Differential Function

IA @Timestamp2

IB @Timestamp2

IC@Timestamp2

ChargingCurrent

DATA FROMLOCALEND

ACTUALVALUES

SETTING

CURRENTDIFFPICKUP:

CURRENTDIFFRESTRAINT1:

CURRENTDIFFRESTRAINT2:

CURRENTDIFFBREAKPT:

SETTING

SETTING

SETTING

SETTING

SETTING

SETTING

SETTING

SETTINGS

Channel 1OK=1

Channel 2OK=1

IA @Timestamp2

IA @Timestamp2

IB @Timestamp2

IB @Timestamp2

IC @Timestamp2

IC @Timestamp2

DTTPHASEA

DTTPHASEA

DTTPHASEB

DTTPHASEB

DTTPHASEC

DTTPHASEC

CURRENTDIFFDTT:

CURRENTDIFFKEYDTT:

L90POWER SYSTEMXC0& XC1:

CURRENTDIFFSOURCE:

CURRENTDIFFTAP1:

CURRENTDIFFTAP2:

L90POWERSYSTEMNUM.OFTERMINALS:

L90POWERSYSTEMNUM.OFCHANNELS:

RUN

RUN

RUN

To RemoteRela yschannel 1& 2

827056A9.CDR

VCG

IC

VBG

IB

Enabled=1

Off

DATA FROMREMOTE1

DATA FROMREMOTE2

RUN

FLEXLOGICOPERANDS

87LDIFFOPA

87LDIFFOPB

87LDIFFOPC

87LDIFFRECVDDTTA

87LDIFFRECVDDTTB

87LDIFFRECVDDTTC

87LDIFF CH2CRCFAIL

87LDIFFKEYDTT

87LDIFFCH1 CRCFAIL

87LDIFF CH2LOSTPKT

87LDIFF CH1LOSTPKT

87LDIFFCH2FAIL

87LDIFFCH1FAIL

87LDIFFPFLLFAIL

87LDIFFOP

ORAND

ORAND

OR

OR

OR

OR

OR

OR

OR

OR

OR

AND

AND

AND

AND

AND

AND

AND

OR

VAG

IA

ComputeChargingCurrent

“3 ” =1

“2” =1

ComputePhasors& Variance(Local)

ComputePhasors& Variance(Remote1)

ComputePhasors& Variance(Remote2)

IC

IC

IC

IA

IA

IA

IB

IB

IB

IA Operate

IARestraint>1

2

2

IB Operate>1

IBRestraint

2

2

ICOperate>1

ICRestraint

2

2

FLEXLOGICOPERAND

STUB BUSOP

ToRemoteRelayschannel 1& 2

RUN

ProcessPhasorsComputations

IC

IA

IB

AND

ND

AND

87LDIFFCH1IDFAIL

87LDIFFCH2IDFAIL

87LBLOCKED

AND

Channel 1IDFail

Channel 2IDFail

AND

AND

AND

AND

AND

AND

ANDOR


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Restraint Current

O p e r a t e C u r r e n t

K1

K2


Traditional Restraint Method

• Traditional method is STATIC

• Compromise between Sensitivity and Security


Dynamic Restraint

• Dynamic restraint uses an estimate of a

measurement error to dynamically increase the

restraint

• On-line estimation of an error is possible owing to

digital measuring techniques

• In digital relaying to measure means to calculate or

to estimate a given signal feature such as magnitude

from the raw samples of the signal waveform


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Digital Phasor MeasurementSliding Data Window

waveform magnitude

windo

w

timetime

present

time

32 samples for

Transmission

of one phaselet

32 samples for

Transmission of

next phaselet


Phasor Goodness of Fit

window

time

• A sum of squared differences between the actual

waveform and an ideal sinusoid over last window is a

measure of a “goodness of fit” (a measurement error)


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Phasor Goodness of Fit

• The goodness of fit is an accuracy index for the digital

measurement

• The goodness of fit reflects inaccuracy due to:

– transients

– CT saturation

– inrush currents and other signal distortions

– electrical noise

• The goodness of fit is used by the L90 to alter the

traditional restraint signal (dynamic restraint)


Operate-Restraint Regions

ILOC – local current

IREM – remote end current

Imaginary (ILOC /IREM)

Real (ILOC /IREM)

OPERATE

OPERATE

OPERATE

OPERATE

RESTRAINT


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Dynamic RestraintDynamic restraint signal =

Traditional restraint signal + Error factor Imaginary (ILOC /IREM)

Real (ILOC /IREM)

OPERATE

REST.

Error factor is high

Error factor is low


Charge Current Compensation

• The L90 calculates the instantaneous values of the

line charging current using the instantaneous values

of the terminal voltage and shunt parameters of the

line

• The calculated charging current is subtracted from

the actually measured terminal current

• The compensation reduces the spurious differential

current and allows for more sensitive settings


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Charge Current Compensation

• The compensating algorithm:

– is accurate over wide range of frequencies

– works with shunt reactors installed on the line

– works in steady state and during transients

– works with both wye- and delta-connected VTs

(for delta VTs the accuracy of compensation is

limited)


Effect of Compensation

0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18-200

-150

-100

-50

0

50

100

150

200

0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18-200

-150

-100

-50

0

50

100

150

200

Voltage, V

time, sec

Local and remote voltages

Time ofenergization

Time of out of zone fault

~


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0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18-0.2

-0.15

-0.1

-0.05

0

0.05

0.1

0.15

0.2

0.25

0.3

0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18-0.2

-0.15

-0.1

-0.05

0

0.05

0.1

0.15

0.2

0.25

0.3



Current, A

time, sec

Traditional and compensated differential

currents (waveforms)

Time of

energization

Theoretical compensated

current

Actual none compensated

current

0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.180

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.180

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08



Current, A

time, sec

Traditional and compensated differential

currents (magnitudes)

Actual none compensated

current after filtering and

Fourier algorithm

Actual compensated current

after filtering and fourier

algorithm


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Self-Synchronization

t0

t1

t2

t3

tf

tr

Forward

travel

time

Return

travel

time

Relay

turn-around

time

RELAY 1 RELAY 2

2

1203 t t t t

t t r f

2

1203 t t t t

t t r f

“ping-pong”


Ping-Pong (example)

Communication path

Initial clocks mismatch=1.4ms or 30°

8.33 ms

8.33 ms

8.33 ms

Store T1i-2=5.1

8.33 ms

t1 t2

Slow down

Relay 1

0

5.1

0

2.3

8.33

8.33 Send T2i-2=2.3

Send T1i-2=5.1

Capture T1i-2=5.1

8.33 ms

Send start bit

Store T1i-3=0Send start bit

Store T2i-3=0

13.4310.53

Send T1i-1=16.66

Capture T2i-2=2.3

16.66

21.76

16.66

18.96

Send T2i-1=16.66

Store T2i-1=16.66

Capture T1i=21.76

Store T2i-2=2.3

Store T1i-1=8.33

Capture T2i=18.96

T2i-3=0

T1i-2=5.1

T1i-1=16.66

T2i=18.96

a2=5.1-0=5.1

b2=18.96-16.66=2.3

2=(5.1-2.3)/2=

= +1.4ms (behind)

T1i-3=0

T2i-2=2.3

T2i-1=16.66

T1i=21.76

a1=2.3-0=2.3

b1=21.76-16.66=5.1

1=(2.3-5.1)/2=

= -1.4ms (ahead)

Speed up

Relay 2

30°0°


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Ping-Pong (example continued)

8.52 ms

8.14 ms

8.14 ms

Store T1i-2=38.28

8.52 ms

t1 t2

Slow down

Relay 1

33.32

38.28

33.32

35.62

41.5541.55

Send T2i-2=35.62Send T1i-2=38.28

Capture T1i-2=38.28

8.52 ms

Store T1i-3=33.32

Store T2i-3=33.32

Send T1i-1=50.00

Capture T2i-2=35.62

50.00

54.03

49.93

53.16

Send T2i-1=49.93

Store T2i-1=49.93Capture T1i=54.03

Store T2i-2=35.62

Store T1i-1=50.00

Capture T2i=53.16

T2i-3=33.32

T1i-2=38.28

T1i-1=50.00

T2i=53.16

a2=38.28-33.32=4.96

b2=53.16-50.00=3.16

2=(4.96-3.16)/2=

= +0.9ms (behind)

T1i-3=33.32

T2i-2=35.62

T2i-1=49.93

T1i=54.03

a1=35.62-33.32=2.3

b1=54.03-49.93=4.1

1=(2.3-4.1)/2=

= -0.9ms (ahead)

Speed up

Relay 2

30°19.5°0°

8.14 ms


Digital “Flywheel”

clock 1 clock 2

“Virtual Shaft”

• If communications is lost, sample clocks continue

to “free wheel”

• Long term accuracy is only a function of the base

crystal stability


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Zero-sequence Current RemovalThe L90 protection system could be applied to lines with tapped

transformer(s) even if the latter has its windings connected in a grounded

wye on the line side and the transformer(s) currents are not measured by

the L90 protection system..

L90-1 L90-2

I_0


CT Saturation Detection

Current differential protection is inherently dependent on adequate CT

performance at all terminals of the protected line especially during

external faults. CT saturation, particularly if happens at one terminal of

the line only, introduces a spurious differential current that may cause the

differential protection to misoperate.


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Breaker-and-a-half The L90 has

advantages on

systems with breaker-

and-a-half or ring bus

configurations. In these

applications, each of

the two three-phase

sets of individual

phase currents (one

associated with eachbreaker) can be used

as an input to a

breaker failure

element.


Breaker-and-a-half

Benefits:

• For restraint forming, maximum of 2 (or more currents is

used). Conventional sum might not provide enough

restraint.

• CTs matching is done

internally, different CT

ratios possible

• Current are available

individually for BF,

metering etc


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Breaker-and-a-half

Distributed bus

differential

Up to 4 CTs can be

processed

individually and

summed up with

L90. For application

where buses are

located remotely,this is beneficial as

CT leads don’t allow

applying bus

differential.


Channel asymmetry

• On SONET/SDH system, transmit and receive channel

delays can be different. Normally, Tx_delay=Rx_delay.

• If one path is broken, it can be re-routed to another

physical fiber, resulting in Tx_delayRx_delay.

RELAY 1

ADM-2 ADM-3

ADM-4

RELAY 2

ADM-1

Tx Rx

TxRx


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Channel asymmetry• Difference in transmit-receive paths is causing

incorrect synchronization between relays as ping-pong is operating based on assumption that transmit-receive delays are the equal.

• That results in apparent differential current,proportional to the value of the channel asymmetry.

• If currents and channel asymmetry are high enough,relay misoperates.

IDIFFIA IB

Half of the channel

asymmetry in

electrical degrees


Channel asymmetry

• L90 can cope with channel asymmetry as high as upto 10 ms using GPS signal.

• No additional input is required-GPS clock isconnected to the regular IRIG-B UR input, providingaccurate clock to both events time-stamping andchannel asymmetry compensation algorithm.

RELAY 1

ADM-2 ADM-3

ADM-4

RELAY 2

ADM-1Tx Rx

TxRx

GPS clock GPS clock


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Channel asymmetry

| Ch1Assymetry | > MAX

REALTIM ECLOCK:IRIG-B SIGNALTYPE

None =0

O R 87LGPSStatus Fail

To Remote RelaysChannels 1and 2

DATA FROM REMOTE

TERMINAL 1

87LCh 1Status (OK=1)

L90POWERSYSTEM:CHNLASYM COMP:

Off = 0

O R

GPS COMPENSATION

Use CalculatedCorrection, Establish andUpdate Memory

Use MemorizedCorrection

RUN

FLEXLOGICOPERAND

87LDIFF GPS FAIL

87LDIFFGPS1FAIL

A N D

SETTINGS

L90POWER SYSTEM:MAX CHNLASYMMETRY:

L90POWER SYSTEM:ROUND TRIPTI MECHANGE:

RUN

|Ch1T-Time New -Ch1T-TIMEOld| > CHANGE

FLEXLOGICOPERAND

87LDIFF1MAX ASYM

FLEXLOGICOPERAND

87LDIFF1TIME CHNG

| Ch2Assymetry | > MAX

RUN

FLEXLOGICOPERAND

87LDIFF2MAX ASYM

FLEXLOGICOPERAND

87LDIFF2TIME CHNG

A N D

Ch1Assymtery

Ch1Round Trip Time

SETTINGS

L90POWERSYSTEM:BLOCK GPS TIMEREF:

Off = 0

FLEXLOGICOPERAND

IRIG-B FAILURE

87LGPS 1Status (OK=1)

FLEXLOGICOPERAND

A N D

O R

|Ch2T-Time New -Ch2T-TIM EOld| > CHANGE

ACTUALVALUES

87LDIFFGPS2FAIL

Ch2Assymtery

FLEXLOGICOPERAND

ACTUALVALUES

DATA FROM REMOTE

TERMINAL 1

A N D

O R

DATA FROM REMOTE

TERMINAL 1

A N D

O R

DATA FROM REMOTE

TERMINAL 2

87LCh 2Status (OK=1)

87LGPS2Status (OK=1) A N D

O R

RUN

ACTUALVALUES

RUN

Ch2Round Trip Time

ACTUALVALUES

GPS function


Channel asymmetry

• Important consideration is fallback mode if GPS signal is

lost: for example, relay can be programmed to continue

to provide sensitive differential function using memorized

value of last measured channel asymmetry until step

change in the communications path is detected.


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Channel asymmetry

Asymmetry-disabled

(about 3 ms of

asymmetry present)

Diff. Current

high

Asymmetry-enabled

(about 3 ms of

asymmetry present)Diff. Current

low


Channel asymmetry

It’s beneficial to monitor

differential current to

raise an alarm if it

becomes relatively high.

This can happen due toasymmetry is present,

problems in CT

secondary. Flexelements

are used for that.


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Synchronization

+

( 2 – 1)/2

time stamps

SystemFrequency

ComputeFrequencyDeviation

Ping-PongPhase

Deviation

Phase FrequencyLoop Filter

f

+

+

+

_

RELAY 1 RELAY 2

f1f – f1

GPSClock

GPSPhaseDeviation

1

( 2 – 1)/2

+

f

+

+

+

_

f2 f – f2

2

time stamps

ComputeFrequencyDeviation

Phase FrequencyLoop Filter

Ping-PongPhase

Deviation

GPSPhaseDeviation

GPSClock

( 2 – 1)/2

( 2 – 1)/2

Overall Relays synchronizationdiagram


Synchronization


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Frequency Tracking1. It is important for current differential to track the

frequency to fit exactly 64 samples within one powercycle and to provide synchronized sampling at eachL90 relay.

2. L90 starts tracking the frequency if current at anyterminal is above 0.125 pu

3. L90 tracks the frequency from positive- sequencecurrent from all terminals.

4. If positive-sequence current is below 0.125 pu, allrelays track to nominal frequency, 50 Hz or 60 Hz.

5. Tracking frequency is displayed in ActualValues\Metering menu.


Benefits

• Increased Sensitivity w ithout sacrif icing Security:

– Fast operation (11.5 cycles)

– Lower restraint settings / higher sensitivity

– Charging current compensation

– Unique precise synchronization with frequency tracking

– Channel Asymmetry Compensation

– CT saturation detection

– Dynamic restraint ensures security during noise, harmonics,CT saturation or transient conditions

– Reduced CT requirements

– Direct messaging

– Increased redundancy due to master-master configuration

– Reliable CRC-32 communication packet protection againstnoise

– Breaker-and-a half applications


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Lab: setting up 87L


Test Set 1 Test Set 2


Lab 1: Setting up 87L

(64Kbps)

Tx Rx

Rx Tx


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L90 Power System menu.



L90 system ischosen

Charging currentenabled/disabled

Channel IDenabled/disabled

Channel IDenabled/disabled

87L Current Differential menu.

87L enabled

Source chosen

Pickup

CT Tap




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87L Current Differential menu.

Slope 1

Slope 2

DTT

External DTT

L90 can accommodate CT ratios mismatch

up to 5 times even if CTs secondary

nominal current is different.

1000/1 2000/5



(64Kbps)

Tx Rx

Rx Tx


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Pickup

Breakpoint

(200% of I nominal)

Restraint 1

Restraint 2

Current Differential major

settings



This portion of logic will not

reset for a continuous

disturbance.

Disturbance Detector-logic

diagram


Lab 1: Setting up 50DD


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Disturbance Detector-element’s menu


Lab 1: Setting up 50DD


Lab 1 Comms Channel Check

Channel Status menu- Actual

Values\Statis\Channel Tests


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Lab 1: Faults Simulation


Test Set

(64Kbps)

Tx Rx

Rx Tx

87L should

operate at the

current…


Test Set

(64Kbps)

Tx Rx

Rx Tx

87L should

NOT operate


Lab 1: 87L Characteristics Check


Test Set 1 Test Set 2

(64Kbps)

Tx Rx

Rx Tx

Operate /

Restraint

Characteristics


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Lab 1: 87L Characteristics Check

User 87L settings

Operate currentRestraint current

Injected currents

Relays response

87LTRIPOP

FLEXLOGICOPERAND

FLEXLOGICOPERAND

FLEXLOGICOPERAND

FLEXLOGICOPERAND

87LTRIPOPA

87LTRIPOPB

87LTRIPOPC

87LTRIP FUNCTION:

AND

AND

AND

AND

SETTING

SETTING SETTING

SETTING

SETTING

SETTING

IA IA >PICKUP

IB IB >PICKUP

IC IC> PICKUP

Enable=1

50DDSV

1-Pole=0

3-Pole=1

87L TRIP SOURCE: 87L TRIP SEAL-IN PICKUP:

87LTRIPSEAL-IN:

87LTRIPSUPV:

FLEXLOGICOPERAND

FLEXLOGICOPERAND

FLEXLOGICOPERAND

FLEXLOGICOPERAND

FLEXLOGICOPERAND

FLEXLOGICOPERAND

87LDIFFOPA

87LRECVDDTT A

87LRECVDDTT B

87LRECVDDTT C

87LDIFFOPB

87LDIFFOPC

87LTRIPMODE:

Enable=1

Disable=0

OR

OR

OR

OR

AND

AND

AND

AND

SETTING

Off=0

87LTRIPFORCE3- :

FLEXLOGICOPERAND

OPEN POLEOP

OR

OR

OR

OR

OR0

50

OR

OR

OR

OR

AND

AND

AND


87L Trip element

87L Trip Logic

87L and DTTare OR-ed

Mode is hosen:

1P or 3P

Supervisingelement 50DD


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87LTRIPOP

FLEXLOGICOPERAND

FLEXLOGICOPERAND

FLEXLOGICOPERAND

FLEXLOGICOPERAND

87LTRIPOPA

87LTRIPOPB

87LTRIPOPC

87LTRIP FUNCTION:

AND

AND

AND

AND

SETTING

SETTING SETTING

SETTING

SETTING

SETTING

IA IA >PICKUP

IB IB >PICKUP

IC IC> PICKUP

Enable=1

50DDSV

1-Pole=0

3-Pole=1

87L TRIP SOURCE: 87L TRIP SEAL-IN PICKUP:

87LTRIPSEAL-IN:

87LTRIPSUPV:

FLEXLOGICOPERAND

FLEXLOGICOPERAND

FLEXLOGICOPERAND

FLEXLOGICOPERAND

FLEXLOGICOPERAND

FLEXLOGICOPERAND

87LDIFFOPA

87LRECVDDTT A

87LRECVDDTT B

87LRECVDDTT C

87LDIFFOPB

87LDIFFOPC

87LTRIPMODE:

Enable=1

Disable=0

OR

OR

OR

OR

AND

AND

AND

AND

SETTING

Off=0

87LTRIPFORCE3- :

FLEXLOGICOPERAND

OPEN POLEOP

OR

OR

OR

OR

OR0

50

OR

OR

OR

OR

AND

AND

AND


87L Trip element

87L Trip Logic

Logic to detectmulti-phaseevolving and

sequential faults

Seal-in outputs if

desirable

Open Poleforces 3P trip

if anotherfault occursduring open

poleconditions

Outputs perphase or 3-phase

Grouped elements


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Grouped elements


Grouped: Stub bus

Line disconnect

switch 52b contact

IOC trigger


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Breaker Breaker

LineStub Bus

zone

+ IOC


Grouped: Stub bus


Grouped: Distance

L90 phase and ground distance is the same as D60 elements.


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L90 backup distance is complimented by line pickup, power swing

detection, POTT and load encroachment.


Grouped: Distance


Grouped: Breaker Failure


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3- Pole Breaker Failure





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Grouped: Open Pole Detector

Control elements


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Control Elements

Control elements

available in L90

Synchrocheck

Logic


Control: Synchrocheck


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Control: Synchrocheck

3-phase

line VT

1-phase

bus VT

Time that the twovoltages remain withinthe admissible angledifference

AutoReclose sequence


Control: AutoReclose


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AutoReclose

logic

FLEXLOGICOPERAND

FLEXLOGICOPERAND

FLEXLOGICOPERAND

FLEXLOGICOPERAND

FLEXLOGICOPERAND

AR3-P/2RIP

SETTING

SETTING

AND

OR

OR

OR

OR

OR

OR AND

OR

AND

AND

AND

AND

AND

OR

OR

ARINCOMPLETESEQ.

TIMER:

ARLO

ARINCOMPLETESEQ

ARFORCE3PTRIP

ARZONE1EXTENT

RESET(tosheet 2)

827089AD.CDR

AR3-PDEADTIME2:

0

0

OR

OR

SETTING

SETTING

Off =0

AND

OR

OR

AREXTENDDEADTIME

1:

CLOSE(topage 2)

ARDEADTIME1

EXTENSION:

0

(Topage2, Reset ARTRANSFERTIMER)

To:ARFORCE3PTRIP

(Evolvingfault)

ARINITIATE

Evolvingfault

BKRFAILTORECLS(fromsheet 2)

ARDISABLED

FLEXLOGICOPERAND

FLEXLOGICOPERAND

FLEXLOGICOPERANDS

AR1-PRIP

AR3-P/1RIP

ARENABLED

ARDISABLED

SETTING

SETTING

LO

OR

OR

OR

AND

OR

AND

AND

OR

OR

OR

AND

AND

AR3-PDEADTIME1:

AR1-PDEADTIME:

0

0

SETTING

0

ARBLKTIMEUPON MAN

CLS:

FLEXLOGICOPERAND

ARRIP

0.5cycle

FLEXLOGICOPERAND

FLEXLOGICOPERAND

SETTING

ARSHOTCOUNT>0

PHASESELECTMULTI-P

D60Relay OnlyFromPhaseSelector

ARPAUSE

SETTING

SETTING

SETTING

SETTING

SETTING

BKRONEPOLEOPEN:

BKR3POLE OPEN:

ARRESET:

ARMULTI-PFAULT:

ARM0DE:

Off =0

Off =0

Off =0

Off =0

Off =0

1& 3Pole

1Pole

3Pole- A

3Pole-B

OR

OR

SHOTCOUNT=MAX

CLOSEBKR1ORBKR2

RESET

BKRONEPOLE OPEN

BKR3POLE OPEN

F r o m s h e e t 3

D 6 0 R e l a y O n l y F r o m T r i p O u t p u t

D60RelayOnly

F r o m S h e e t 2

FLEXLOGICOPERAND

FLEXLOGICOPERAND

SETTING

TRIP1-POLE

LINEPICKUP OP

TRIPARINIT3-POLE

AR3PTDINIT:

SETTING

SETTING

SETTING

SETTING

Enable=1

Disable=0

ARFUNCTION:

ARBLOCK:

ARBKRMANCLOSE:

BKRMA NUALCLOSE:

AR1PINIT:

Off =0

Off =0

Off =0

SETTING

AR3PINIT:

Off =0

Off=0

OR

(Fromsheet3)

FLEXLOGICOPERAND

5ms

0

ANDOR



AutoReclose

logic

BKRCLOSED(frompage3)

RESET

Tosheet 3

LO

LO

LO

LO

AND

AND

827090A9.CDR

2ms

2ms

OR

OR

OR

OR

S

ROR

Latch

AND

AND

AND

AND

OR

OR

OR

AND

AND

AND

AND

AND

AND

OR

AND

AND




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AutoReclose

logic



This piece of the AR is

reading status of

breaker(s) and feeds

main AR logic to

proceed action further

accordingly number of

breakers, mode chosen

and sequence chosen.

Breaker Function AutoReclosure Function

LEDs



Breakers are set inSystem Setup\

Breakers

AR is set per user ’srequirements (reads

breakers status

automatically) LEDs are needed to

know AR ststus


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CT Fail Detector is designed to detect

failures in CT secondary circui try


Control: CT Fail Detector


Control: VT Fuse Fail


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POTT scheme requires 1-bit

comms channel, for example

PLC.


Control: POTT

L90 1

Line 2

Line 1

C60 3

L90 1-2 LAN

L90 2

B3

B2

B1

B4

Substation 1

Ethernet

Substation

2

B5

Ethernet


Direct Inputs and Outputs


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This is activein 3-terminal

only

Defaultmeans state

whenchannel is

brokenDirect

Outputs areassigned with

Flexlogicoperands



Channel statuscontrols either

Direct Input is readfrom the received

data or set todefault


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Local Relay Remote Relay



Direct Input 1-1 (BFat remote S/S) isassigned to a trip

gate.

Example

Breaker Fail isassigned to Direct

Output 1-1

Monitoring & Metering


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Metering: 87L


Oscillography: 87L analogs


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Thank you.

l90 complete agenda

Documents