ur protect

7/29/2019 Ur Protect

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Protection Overview

Universal Relay Family


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Power Management The Universal Relay

Contents...

Configurable Sources

FlexLogic and Distributed FlexLogic

L90 Line Differential Relay

D60 Line Distance Relay

T60 Transformer Management Relay

B30 Bus Differential Relay

F60 Feeder Management Relay


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Configurable Sources


4/139


A W 51P

V

I

Source

Metering Protection

Universal Relay

I

Concept of Sources

Configure multiple three phase current and

voltage inputs from different points on thepower system into Sources

Sources are then inputs to Metering and

Protection elements


5/139


Sources:Typical Applications

Breaker-and-a-half schemes

Multi-winding (multi-restraint)Transformers

Busbars

Multiple Feeder applications

Multiple Meter

Synchrocheck


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Transformer

CT1 CT2

CT3

VT1

87T

50BF

50BF

W

50P

Sources Example 1: Breaker-and-a-Half Scheme


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Transformer

CT1 CT2

CT3

VT1

87T

50BF50BF

W

50P

50BF

RELAY

50BF

RELAY

50P

87T

AMPS

Transformer Differential

Relay

External

Summation

VOLT

WAMPS

Sources Example 1:Traditional Relay Application


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VT1

CT1

CT2

CT3

Sources Example 1: Inputs into the Universal Relay


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VT1

VV

II

I

VI

II

VCT1

CT2

VI

II

V

CT3

50BF

50BF

VI

II

V

50P W

87T

Source #1

Source #2

Source #3

Source #4

Physical 3-phase

I &V Inputs

CT1

CT2

CT1

CT2

ConfigureS

ources

(donevias

ettings)

VT1

CT3

Universal Relay

Sources Example 1: Universal Relay solution using Sources


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T1

CT1 CT2

CT3

VT1

87T

50BF50BF

W

50P

CT4

Sources Example 2:Breaker-and-a-Half Scheme with 3-Winding Transformer


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VT1

CT1

CT2

CT3

CT4



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VT1

VV

II

I

VI

II

VCT1

CT2

VI

II

V

CT3

50BF

50BF

VI

II

V

50P W

87T

Source #1

Source #2

Source #3

Source #4

Physical 3-phase

I &V Inputs

CT1

CT2

CT1

CT2

ConfigureS

ources

(donevias

ettings)

VT1

CT3

CT4

VI

II

V

CT4 Source #5

Universal Relay



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VT127P

W

50/

51

CT4

81

W

50/

51

CT3

81

W

50/

51

CT2

81

W

50/

51

CT1

81

W

50/

51

81

CT5

51W

Multiple Feeder + BusbarSources Example 3: Busbar with 5 feeders


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VT1

CT1

CT2

CT3

CT4

CT5



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VT1

VV

II

I

VI

II

V

CT1

CT2

VI

II

V

CT3

50/51 81

VI

II

V

Source #1

Physical 3-phase

I &V Inputs

CT1

ConfigureS

ources

(doneviasettings)

CT4

VI

II

V

CT5

VT1

VI

II

V

CT2

VT1

CT3

VT1

CT4

VT1

CT5

VT1

W

CT1..CT5

VT1

50/51 81Source #2

W

50/51 81Source #3

W

50/51 81Source #4

W

50/5181

Source #5W

51 27PSource #6

WUniversal

Relay



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FlexLogicTM

&

Distributed FlexLogicTM

F i l A hi


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Analog

Inputs

Programmable

Logic

(FlexLogic)

Virtual

Outputs

Ethernet (Fiber)

Digital

Inputs

VirtualInputs Remote

Inputs

Digital

Outputs

Computed

Parameters

Metering

Protection & Control

Elements

Remote

Outputs

A/D

DSP

Hardware

Software

Ethernet LAN (Dual Redundant Fiber)

Universal Relay: Functional Architecture


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AND

AND

AND

OR

Remote Input: Trip Relay 2




Local: Trip

Local: Trip

ENABLE

ENABLE

ENABLE

0ms0ms

Remote

Output

Digital

Output

Substation LAN

LOCAL RELAY

RELAY 2 RELAY 3Local

RELAY

Distributed FlexLogic Example 1:2 out of 3 Trip Logic Voting Scheme


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Distributed FlexLogic Example 1:Implementation of 2 out of 3 Voting Scheme


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Distributed FlexLogic Example 2:Transformer Overcurrent Acceleration

UR-F60

Feeder IED

UR-F60

Feeder IED

UR-F60

Feeder IED

UR-T60

Transformer I ED

TIME

Current Pick-Up Level

Coordination

Time

Feeder TOC Curve

Transformer

TOC Curve

Accelerated

Transformer

TOC Curve

Substation LAN: 10/100 Mbps Ethernet

(Dual Redundant Fiber)

Transformer IED:IF Phase or Ground TOC pickup THEN send GOOSE message to ALL Feeder IEDs.

Feeder IEDs:Send No Fault GOOSE if no TOC pickup ELSE Send Fault GOOSE if TOC pickup.

Transformer IED:If No Fault GOOSE from any Feeder IED then switch to accelerated TOC curve.

Animation

Fl L i B fit
http://localhost/var/www/apps/conversion/tmp/scratch_7/urlogo.html


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FlexLogic: Benefits

FlexLogic

Tailor your scheme logic to suit the applicationAvoid custom software modifications

Distributed FlexLogic

Across the substation LAN (at 10/100Mpbs)allows high-speed adaptive protection and

coordination

Across a power system WAN (at 155Mpbs

using SONET system) allows high-speed

control and automation


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L90

Line Differential Relay

L90 C t Diff ti l R l Features


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L90 Current Differential Relay: Features

Protection:

Line current differential (87L)

Trip logic

Phase/Neutral/Ground TOCs

Phase/Neutral/Ground IOCs

Negative sequence TOC

Negative sequence IOC

Phase directional OCs

Neutral directional OC

Phase under- and overvoltage

Distance back-up

L90 C t Diff ti l R l Features


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L90 Current Differential Relay: Features

Control:

Breaker Failure (phase/neutral amps)

Synchrocheck & Autoreclosure

Direct messaging (8 extra inter-relay DTT bitsexchanged)

Metering:Fault Locator

Oscillography

Event Recorder

Data Logger

Phasors / true RMS / active, reactive andapparent power, power factor


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Direct point-to-point Fiber

(up to 70Km)

ORVia SONET system telecom multiplexer

(GEs FSC)

FSC(SONET)

FSC

(SONET)

(64Kbps)

(155Mbps)

- G.703- RS422

- G.703- RS422

L90 Current Differential Relay: Overview

L90 Current Differential Relay: LineCurrentDifferential


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L90 Current Differential Relay: Line Current Differential

Improved operation of the line current

differential (87L) element:dynamic restraint increasing security without

jeopardizing sensitivity

line charge current compensation to increase

sensitivity

self-synchronization

L90 Current Differential Relay: Traditional RestraintMethod


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Restraint Current

Opera

teCurrent

K1

K2

L90 Current Differential Relay:Traditional Restraint Method

Traditional method is STATIC

Compromise between Sensitivity and Security

L90 Current Differential Relay: Dynamic Restraint


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Dynamic restraint uses an estimate of a

measurement error to dynamically increasethe restraint

On-line estimation of an error is possible

owing to digital measuring techniques In digital relaying to measuremeans to

calculateorto estimatea given signal

feature such as magnitude from the rawsamples of the signal waveform

L90 Current Differential Relay: Digital Phasor Measurement


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L90 Current Differential Relay: DigitalPhasor Measurement

The L90 measures the current phasors

(magnitude and phase angle) as follows:digital pre-filtering is applied to remove the

decaying dc component and a great deal of high

frequency distortions

the line charging current is estimated and used

to compensate the differential signal

full-cycle Fourier algorithm is used to estimate

the magnitude and phase angle of thefundamental frequency (50 or 60Hz) signal



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Sliding Data Window

waveform magnitude

window

timetime

present

time



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Sliding Data Window

waveform magnitude

window

timetime

windowwindowwindowwindowwindowwindowwindow

L90 Current Differential Relay: Goodnessof Fit


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L90 Current Differential Relay: Goodness of Fit

window

time

A sum of squared differences between the

actual waveform and an ideal sinusoid overlast window is a measure of a goodness of

fit (a measurement error)

L90 Current Differential Relay: Phasor Goodnessof F it


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L90 Current Differential Relay: Phasor Goodness of F it

The goodness of fit is an accuracy index for

the digital measurement The goodness of fit reflects inaccuracy due to:

transients

CT saturationinrush currents and other signal distortions

The goodness of fit is used by the L90 to alter

the traditional restraint signal (dynamicrestraint)

L90 Current Differential Relay: Operate-RestraintRegions


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L90 Current Differential Relay: Operate Restraint Regions

ILOClocal current

IREMremote end current

Imaginary (ILOC/IREM)

Real (ILOC/IREM)

OPERATE

OPERATE

OPERATE

OPERATE

RESTRAINT



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Dynamic restraint signal =

Traditional restraint signal + Error factor

Imaginary (ILOC/IREM)

Real (ILOC/IREM)

OPERATE

REST.

Error factor is high

Error factor is low

L90 Current Differential Relay: ChargeCurrentCompensation


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L90 Current Differential Relay: Charge Current Compensation

The L90 calculates the instantaneous values

of the line charging current using theinstantaneous values of the terminal voltage

and shunt parameters of the line

The calculated charging current issubtracted from the actually measured

terminal current

The compensation reduces the spuriousdifferential current and allows for more

sensitive settings

L90 Current Differential Relay: ChargeCurrentCompensation


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L90 Current Differential Relay: Charge Current Compensation

The compensating algorithm:

is accurate over wide range of frequenciesworks 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)

L90 Current Differential Relay: Effectof Compensation


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L90 Current Differential Relay: 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

Voltage, V

time, sec

Localandremotevoltages



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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


Current, A

time, sec

Traditionalandcompensateddifferential

currents (waveforms)



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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

Traditionalandcompensateddifferential

currents (magnitudes)

L90 Current Differential Relay: Self-Synchronization


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L90 Current Differential Relay: Self Synchronization

t0

t1

t2

t3

tf

tr

Forward

travel

time

Return

travel

time

Relayturn-around

time

RELAY 1 RELAY 2

2

1203 tttttt rf

ping-pong

L90 Current Differential Relay: Ping-Pong (example)


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90 Cu e t e e t a e ay: g o g(e a pe)

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=8.33

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=16.66T2i=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=0T2i-2=2.3

T2i-1=16.66

T1i=21.76

a1=2.3-0=2.3b1=21.76-16.66=5.1

1=(2.3-5.1)/2=

= -1.4ms (ahead)

Speed up

Relay 2

300

L90 Current Differential Relay: Ping-Pong (example cnt.)


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y g g ( p )

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=49.93

Capture T1i=54.03

Store T2i-2=35.62

Store T1i-1=50.00

Capture T2i=53.16

T2i-3=33.32

T1i-2=38.28T1i-1=50.00

T2i=53.16

a2=38.28-33.32=4.96

b2=53.16-50.00=3.162=(4.96-3.16)/2=

= +0.9ms (behind)

T1i-3=33.32T2i-2=35.62

T2i-1=49.93

T1i=54.03

a1=35.62-33.32=2.3b1=54.03-49.93=4.1

1=(2.3-4.1)/2=

= -0.9ms (ahead)

Speed up

Relay 2

3019.50

8.14 ms

L90 Current Differential Relay:Digital Flywheel


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clock 1 clock 2

Virtual Shaft

y g y

If communications is lost, sample clocks

continue to free wheel

Long term accuracy is only a function of thebase crystal stability

L90 Current Differential Relay: Peer-to-Peer Operation


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y p

Each relay has sufficient information to make

an independent decision

Communication redundancy

L90-1 L90-2

L90-3

L90 Current Differential Relay: Master-Slave Operation


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y p

At least one relay has sufficient information to

make an independent decision

The deciding relay(s) sends a transfer-tripcommand to all other relays

L90-1 L90-2

L90-3 Data (currents)

Transfer Trip

L90 Current Differential Relay: Benefits


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y

Increased Sensitivity without sacrificing

Security:Fast operation (11.5 cycles)

Lower restraint settings / higher sensitivity

Charging current compensationDynamic restraint ensures security during CT

saturation or transient conditions

Reduced CT requirements

Direct messaging

Increased redundancy due to master-master

configuration

L90 Current Differential Relay: Benefits


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y

Self-Synchronization:

No external synchronizing signal requiredTwo or three terminal applications

Communication path delay adjustment

Redundancy for loss of communications Benefits of the UR platform (back-up

protection, autoreclosure, breaker failure,

metering and oscillography, event recorder,

data logger, FlexLogicTM, fast peer-to-peer

communications)


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D60

Line Distance Relay

D60 Line Distance Relay: Features


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Protection:

Four zones ofdistance protection

Pilot schemes



Negative sequence TOC

Negative sequence IOC

Phase directional OCs

Neutral directional OC

Negative sequence directional OC



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Protection (continued):


Power swing blocking

Out of step tripping

Control:

Breaker Failure (phase/neutral amps)

Synchrocheck

Autoreclosure



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Metering:

Fault Locator

Oscillography

Event Recorder

Data Logger

Phasors / true RMS / active, reactive and

apparent power, power factor

D60 Line Distance Relay: Stepped Distance


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Four zones of stepped distance:

individual per-zone per-element characteristic: dynamic memory-polarized mho

quadrilateral

individual per-zone per-element current

supervision

multi-input phase comparator:

additional ground directional supervision

dynamic reactance supervisionall 4 zones reversible

excellent transient overreach control

D60 Line Distance Relay: Zone 1 andCVT transients


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Capacitive Voltage Transformers (CVTs)

create certain problems for fast distancerelays in conjunction with high Source

Impedance Ratios (SIRs):

the CVT induced transient voltage components

may assume large magnitudes (up to about 30-

40%) and last for a comparatively long time (up

to about 2 cycles)

the 60Hz voltage for faults at the relay reachpoint may be as low as 3% for a SIR of 30

the signal is buried under the noise



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0.05 0.06 0.07 0.08 0.09 0.1 0.11 0.12

-1

-0.8

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

0.8

1

Voltage[pu]

time [sec]

"High-C CVT" (CVT-1)

"Extra-High-C CVT" (CVT-2)

0 0.01 0.02 0.03 0.04 0.05-0.1

-0.05

0

0.05

0.1

0.15

0.2

0.25

0.3

i

l

NOISE COMPONENT 2

60Hz SIGNAL

NOISE COMPONENT 1

Sample CVT output voltages

(the primary voltage drops

to zero)

Illustration of the

signal-to-noise ratio



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CVTs cause distance relays to overreach

Generally, transient overreach may becaused by:

overestimation of the current (the magnitude of

the current as measured is larger than its actual

value, and consequently, the fault appears

closer than it is actually located),

underestimation of the voltage (the magnitude

of the voltage as measured is lower than itsactual value)

combination of the above



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0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2-5

-4

-3

-2

-1

0

1

2

3

4

5x 10

5

voltagewaveform

estimatedamplitude

(a)

Estimated voltage magnitude

does not seem to be underestimated

0.04 0.05 0.06 0.07 0.08 0.09 0.1 0.11 0.12 0.13-4

-3

-2

-1

0

1

2

3

4

x 104

2.2% of the nominal =

70% of the actual value



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-10 -5 0 5 10-5

0

5

10

15

Reactance[ohm]

Resistance [ohm]

18

22

26

30

3442

44 Actual FaultLocation

LineImpedance

Trajectory(msec)

dynamic mhozone extendedfor high SIRs

Impedance locus may pass

below the origin of the Z-plane -

this would call for a time delay

to obtain stability



59/139


Transient overreach due to CVTs -

solutions:apply delay (fixed or adaptable)

reduce the reach

adaptive techniques and better filtering

algorithms



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0 5 10 15 20 25 300

10

20

30

40

50

60

70

80

90

100

MaximumRach[%]

SIR

Actual maximum reach curves

Relay A

Relay D

Relay S

D60



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D60 Solution:

Optimal signal filtering currents - max 3% error due to the dc component

voltages - max 0.6% error due to CVT transients

Adaptive double-reach approach

the filtering alone ensures maximum transient

overreach at the level of 1% (for SIRs up to 5) and

20% (for SIRs up to 30)

to reduce the transient overreach even further an

adaptive double-reach zone 1 has been implemented



62/139


The outer zone 1:

is fixed at the actual reachapplies certain security delay to cope with CVT

transients

DelayedTrip

InstantaneousTrip

R

X

The inner zone 1:has its reach

dynamically

controlled by the

voltage magnitude

is instantaneous



63/139


No Trip

Delayed

Trip

Instantaneous

Trip

Set reach



64/139


0 0.2 0.4 0.6 0.8 10.75

0.8

0.85

0.9

0.95

1

Elements Voltage, pu

Multiplierfortheinn

erzone1reach,pu



65/139


Performance:

excellent transient overreach control (5% up toa SIR of 30)

no unnecessary decrease in speed

D60 Line Distance Relay: Zone 1 Speed


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Phase Element

0

5

10

15

20

25

30

0% 10% 20% 30% 40% 50% 60% 70% 80%

Fault Location [%]

OperatingTime[ms]

SIR = 0.1

SIR = 1

SIR = 10

SIR = 20

SIR = 30

D60 Line Distance Relay: Zone 1 Speed


67/139


Ground Element

0

5

10

15

20

25

30

35

0% 10% 20% 30% 40% 50% 60% 70% 80%

Fault Location [%]

OperatingTime[ms]

SIR = 0.1

SIR = 1

SIR = 10

SIR = 20

SIR = 30

D60 Line Distance Relay: Pilot Schemes


68/139


Pilot Schemes available:

Direct Underreaching Transfer Trip (DUTT)

Permissive Underreaching Transfer Trip (PUTT)

Permissive Overreaching Transfer Trip (POTT)

Hybrid Permissive Overreaching Transfer Trip

(HYB POTT)

Blocking Scheme

D60 Line Distance Relay: Pilot Schemes


69/139


Pilot Schemes - Features:

integrated functions : weak infeed

echo

line pick-up

basic protection elements used to key thecommunication:

distance elements

fast and sensitive ground (zero- and negative

sequence) directional IOCs with

current/voltage/dual polarization

D60 Line Distance Relay: Benefits


70/139


Excellent CVT transient overreach control

(without unnecessary decrease in speed) Fast, sensitive and accurate ground

directional OCs

Common pilot schemes Benefits of the UR platform (back-up

protection, autoreclosure, breaker failure,

metering and oscillography, event recorder,data logger, FlexLogicTM, fast peer-to-peer

communications)


71/139


T60

Transformer Management Relay

T60 Transformer Management Relay: Features


72/139


Protection:

Restrained differential

Instantaneous differential overcurrent

Restricted ground fault




Underfrequency

T60 Transformer Management Relay: Features


73/139


Metering:

Oscillography

Event Recorder

Data Logger

Phasors / true RMS / active, reactive and

apparent power, power factor

T60 Transformer Management Relay: Restrained differential


74/139


Internal ratio and phase compensation

Dual-slope dual-breakpoint operatingcharacteristic

Improved dynamic second harmonic

restraint for magnetizing inrush conditions Fifth harmonic restraint for overexcitation

conditions

Up to six windings supported

T60 Transformer Management Relay: Differential Signal


75/139


Removal of the zero sequence component

from the differential signal:optional for delta-connected windings

enables the T60 to cope with in-zone grounding

transformers and in-zone cables with significant

zero-sequence charging currents

Removal of the decaying dc component

Full-cycle Fourier algorithm for measuring

both the differential current phasor and the

second and fifth harmonics

T60 Transformer Management Relay: Restraining Signal


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Removal of the decaying dc component

Full-cycle Fourier algorithm for measuringthe magnitude

Maximum of principle used for deriving

the restraining signal from the terminalcurrents:

the magnitude of the current flowing through a

CT that is more likely to saturate is used

T60 Transformer Management Relay: Operating Characteristic


77/139


Two slopes used to cope with:

small errors during linear operation of the CTs(K1) and

large CT errors (saturation) for high through

currents (K2)

differential

restrainingA

B1

K2

K1

B2

T60 Transformer Management Relay: Operating Characteristic


78/139


Two breakpoints used to specify:

the safe limit of linear CT operation (B1) andthe minimum current level that may cause large

spurious differential signals due to CT

saturation (B2)

differential

restrainingA

B1

K2

K1

B2

T60 Transformer Management Relay: Magnetizing Inrush


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0 1 2 3 4 5 6 7 8 9 10 11 Time (cycles)

0

500

1000

1500

-400

i [A] (a)

0 1 2 3 4 5 6 7 8 9 100

0.2

0.4

0.6

0.8

1

Time (cycles)

I2

/ I1

(b)

Sample magnetizing

inrush current

Second harmonic

ratio

T60 Transformer Management Relay: Magnetizing Inrush


80/139


New second harmonic restraint:

uses both the magnitude and phase relationbetween the second harmonic and the

fundamental frequency (60Hz) component

Implementation issues:

the second harmonic rotates twice as fast as the

fundamental component (60Hz)

consequently the phase difference between the

second harmonic and the fundamentalcomponent changes in time...

T60 Transformer Management Relay: New Inrush Restraint


81/139


Fundamental

phasor

2nd harmonicphasor

121

2

1

221 arg2arg II

I

I

eI

II

tj

Solution:

http://localhost/var/www/apps/conversion/tmp/scratch_7/T60_movie_inrush.mov


82/139


Inrush Pattern

3D View

http://localhost/var/www/apps/conversion/tmp/scratch_7/T60_movie_inrush.movhttp://localhost/var/www/apps/conversion/tmp/scratch_7/T60_movie_internal_faults.mov


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Internal Fault Pattern

3D View

http://localhost/var/www/apps/conversion/tmp/scratch_7/T60_movie_internal_faults.mov


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Basic Operation:

if the second harmonic drops magnitude-wisebelow 20%, the phase angle of the complex

second harmonic ratio is close to either +90 or

-90 degrees during inrush conditions

the phase angle may not display the 90-degreepattern if the second harmonic ratio is above

some 20%

if the second harmonic ratio is above 20% the

restraint is in effect, if it is below - the restraint

and its duration depend on the phase angle



85/139


0

30

60

90

12 0

15 0

18 0

21 0

24 0

27 0

30 0

33 0

0.4

0.3

0.2

0

0.1

0OPERATE

0

30

60

90

12 0

15 0

18 0

21 0

24 0

27 0

30 0

33 0

0.4

0.3

0.2

0.1

0

New restraint

characteristic

The characteristic is

dynamic



86/139




87/139


-0.2 -0.1 0 0.1 0.2 0.3

-0.25-0.2

-0.15

-0.1

-0.05

0

0.05

0.1

0.15

0.2

0.25

0

.1

0.1

0.1

0.1

0

.1

0.1

0.1

0.1

1

1

1

1

1

1

11

2

2

2

2

2

2

2

23

3 3 3

3

33

3

4

4 4

4

4

44

5

55

5

5

5

5

Effective restraint characteristic:

time (cycles) the restraint is kept

vs. complex second harmonic ratio



88/139


Effective restraint characteristic:

time for which the restraint is kept

vs. complex second harmonic ratio

3D View

T60 Transformer Management Relay: Benefits
http://localhost/var/www/apps/conversion/tmp/scratch_7/T60_movie_time_char.mov


89/139


Up to six windings supported

Improved transformer auto-configuration Improved dual-slope differential

characteristic

Improved second harmonic restraint Benefits of the UR platform (back-up

protection,metering and oscillography,

event recorder, data logger, FlexLogicTM

,fast peer-to-peer communications)


90/139


B30

Bus Differential Relay

B30 Bus Differential Relay: Features

C fi ti


91/139


Configuration:

up to 5 feeders with bus voltage

up to 6 feeders without bus voltage


P t ti


92/139


Protection:

Biased differential protection

CT saturation immunity

typical trip time < 15 msec

dynamic 1-out-of-2 or 2-out-of-2 operation

Unbiased differential protectionCT trouble


Metering:


93/139


Metering:

Oscillography

Event Recorder

Data Logger

Phasors / true RMS

active, reactive and apparent power, powerfactor (if voltage available)

B30 Bus Differential Relay: CT saturation problem


94/139


During an external fault

the fault current may be supplied by a numberof sources

the CTs on the faulted circuit may saturate

Saturation of the CTs creates a current

unbalance and violates the differential principle

The conventional restraining current may not be

sufficient to prevent maloperation

CT saturation detection and other operatingprinciples enhance the through-fault

stability

B30 Bus Differential Relay: DIF-RES trajectory

DIF diff ti l


95/139


External

fault: ideal

CTs

diffe

rential

restrainingA

B1

K2

K1

B2

DIF differentialRES restraining



96/139


External

fault: ratio

mismatch

diffe

rential

restrainingA

B1

K2

K1

B2



97/139


External

fault: CT

saturation

diffe

rential

restrainingA

B1

K2

K1

B2



98/139


Internal

fault: high

current

diffe

rential

restrainingA

B1

K2

K1

B2



99/139


Internal

fault: low

current

diffe

rential

restrainingA

B1

K2

K1

B2



100/139


External

fault:

extreme CT

saturation

diffe

rential

restrainingA

B1

K2

K1

B2

B30 Bus Differential Relay: Operating principles


101/139


Combination of

Low-impedancebiased differential

Directional (phase comparison)

Adaptively switched between

1-out-of-2 operating mode

2-out-of-2 operating mode

by

Saturation Detector

B30 Bus Differential Relay:Two operating zones


102/139


low currents

saturation possible

due to dc offset

saturation verydifficult to detect

more security

required

differential

restraining

A

B1

K2

K1

B2

DIF1

B30 Bus Differential Relay:Two operating zones


103/139


large currents

quick saturation

possible due to

large magnitude

saturation easierto detect

security required

only if saturation

detected

differential

restraining

A

B1

K2

K1

B2

DIF2

B30 Bus Differential Relay: Logic


104/139


DIF1

DIR

SAT

DIF2

O

RAND

O

R

TRIP

AND



105/139


diffe

rential

restrainingA

B1

K2

K1

B2

1-out-of-2 (DIF) if no saturation

2-out-of-2 (DIF+DIR) if saturation

detected

2-out-of-2

(DIF+DIR)



106/139


DIF1

DIR

SAT

DIF2

O

RAND

O

R

TRIP

AND

B30 Bus Differential Relay: Directional principle


107/139


Internal faults - all currents approximately

in phase



108/139


External faults - one current approximately

out of phase


h k ll h l


109/139


Check all the angles

Select the maximum current contributor andcheck its position against the sum of all the

remaining currents

Select major current contributors and checktheir positions against the sum of all the

remaining currents



110/139

Power ManagementThe Universal Relay

"contributor"(phasor)

differential less"contributor"

(phasor)

BLOCK

TRIP

TRIP

BLOCK

BLOCK



111/139


BLOCK OPERATE

BLOCK

BLOCK

pD

p

II

Ireal

pD

p

II

Iimag

Ip

ID

- Ip

External Fault Conditions

OPERATE

BLOCK

ALIM

-ALIM



112/139


BLOCK

BLOCK

BLOCK

pD

p

II

Ireal

pD

p

II

Iimag

Ip

ID

- Ip

Internal Fault Conditions

OPERATE

OPERATE

BLOCK



113/139


DIF1

DIR

SAT

DIF2

OR

AND

OR

TRIP

AND

B30 Bus Differential Relay: Saturation Detector

diff ti l t i i t j t


114/139


differential-restraining trajectory

dI/dt

differen

tial

restrainingA

B1

K2

K1

B2


S l E t l


115/139


0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45-40-20

0

20

40

Fe

eder1

0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45-40

-20

0

20

40

Feeder2

0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45-40

-200

20

40

Feede

r3

0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45-40

-20

0

20

40

Feeder4

0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45-40

-20

0

2040

Feeder5

Time, sec

Sample External

Fault (Feeder 1)


A l i f th DIF


116/139


0 5 10 15 20 25 30 350

5

10

15

20

25

30

35

Differential[A]

Restraining [A]

12 3 4 56

789

101112

13

1415

16

171819

2021222324252627282930313233

Phase A (Infms)

Analysis of the DIF-

RES trajectory enables

the B30 to detect CTsaturation


Sample E ternal


117/139


0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45-20

0

20

Feeder1

0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45-20

0

20

Feeder2

0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45-20

0

20

Feeder3

0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45-20

0

20

Feeder4

0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45-20

0

20

Feeder5

Time, sec

Sample External

Fault (Feeder 4) -

severe CT saturationafter 1.5msec


dI/dt principle enables


118/139


0 5 10 15 200

5

10

15

20

Differential[A]

Restraining [A]

12

3

4

56

7

8

9101112131415

16

1718

19

20

2122

23

24

252627282930

313233

Phase A (Infms)

d /dt p c p e e ab es

the B30 to detect CT

saturation



119/139


NORMAL

SAT := 0

EXTERNAL

FAULT

SAT := 1

EXTERNALFAULT / CT SAT

SAT := 1

DIF=1DIF=0for 100msec

IDI F

< K1*I

RES

for 200msec

"saturation"condition


Operation:


120/139


Operation:

The SAT flag WILL NOT set during internal

faults whether or not the CT saturates

The SAT flag WILL SET during external faults

whether or not the CT saturates

The SAT flag is NOT used to block the relaybut to switch to 2-out-of-2 operating principle

B30 Bus Differential Relay: Benefits

Sensitive settings possible


121/139


Sensitive settings possible

Very good through-fault stability Fast operation (less than 3/4 of a cycle)

Benefits of the UR platform (back-up

protection,metering and oscillography,event recorder, data logger, FlexLogicTM,

fast peer-to-peer communication)

B30 Bus Differential Relay: Extensions


122/139

Power ManagementThe

Universal Relay

6 feeders

6 feeders

6 feeders

fast

communication


123/139


F60

Feeder Management Relay

F60 Feeder Relay: Features

Protection:


124/139


Phase/Neutral/Ground IOC & TOC

Phase TOC with Voltage Restraint/Supervision

Negative sequence IOC & TOC

Phase directional supervision

Neutral directional overcurrentNegative sequence directional overcurrent

Phase undervoltage & overvoltage

UnderfrequencyBreaker Failure (phase/neutral supervision)

F60 Feeder Relay: Features

Control:


125/139


Manually Control up to Two Breakers

Autoreclosure & Synchrocheck

FlexLogic

Metering:

Fault Locator

Oscillography

Event Recorder

Data LoggerPhasors / true RMS / active, reactive and

apparent power, power factor, frequency

F60 Feeder Relay: Phase Directional Element

Directional element


126/139


Directional element

controls the RUN

command of the

overcurrent element

(emulation of

torque control)

Memory voltage

polarization held for

1 second

VBGVCG

VAG(Faulted) IA

IA = operating current

Phasors for Phase A Polarization:

ECAset @ 30o

VPol = VBC*(1/_ECA) = polarizing vol tage

BLOCK

ECA = Element Characterist ic Angle @ 30o

Fault angleset @ 60o Lag

VAG(Unfaulted)

VBC

VBC

VPol

+90o

-90o

F60 Feeder Relay: Neutral Directional Element

Single protection element providing both


127/139



forward and reverse looking IOC

Independent settings for the forward and

reverse elements

Voltage, current or dual polarization

Fast and secure operation due to the energy

based comparator and positive sequence

restraint

F60 Feeder Relay: Ground Directional Elements

Limitations of Fast Ground Directional


128/139


Limitations of Fast Ground Directional

IOCs:

Spurious zero- and negative-sequence voltages

and currents may appear transiently due to the

dynamics of digital measuring algorithms

Magnitude of such spurious signals may reachup to 25% of the positive sequence quantities

Phase angles of such spurious signals are

random factors

Combination of the above may cause

maloperations


Sample three-phase


129/139


0.05 0.1 0.15 0.2 0.25-25

-20

-15

-10

-5

0

5

10

15

20

25

time [sec]

fault currents


Sample three-phase


130/139


-10 -5 0 5 10

-10

-5

0

5

10

Real

Imag

inary

fault currents (phasors)

Pre-fault phasors

(symmetrical)

Fault phasors

(symmetrical)

Transient phasors

(slightly asymmetrical)Transient phasors

(slightly asymmetrical)


Sample three-phase


131/139


0.05 0.1 0.15 0.2 0.250

2

4

6

8

10

12

14

time [sec]

currents (symmetrical

components)

Positive Sequence

Negative Sequence

Zero Sequence


Solutions to the problem of spurious zero


132/139


Solutions to the problem of spurious zero

and negative sequence quantities:

do not allow too sensitive settings

apply delay

new approach:

energy based comparator

positive sequence restraint


Operating power is calculated as a


133/139


Operating power is calculated as a

function of:

magnitudes of the operating and polarizing

signals

the angle between the operating and polarizing

signals in conjunction with the characteristicand limit angles

Restraining power is calculated as a

product of magnitudes of the operating andrestraining signals


The powers are averaged over certain


134/139


The powers are averaged over certain

short period of time creating the operating

and restraining energies

The element operates when

Both forward and reverse operating

energies are calculated The factorK is lower for the reverse

looking element to ensure faster operation

EnergygRestraininEnergyOperating K


50

Forward looking


135/139


0.05 0.1 0.15 0.2 0.25-20

-10

0

10

20

30

40

time [sec]

0.05 0.1 0.15 0.2 0.25-15

-10

-5

0

5

10

15

20

time [sec]

Reverse looking

element

elementRestraining Energy

Restraining Energy

Operating Energy

Operating Energy

Despite spurious

negative sequence

neither the forward northe reverse looking

element maloperate


Positive Sequence Restraint:


136/139


Positive Sequence Restraint:

Classical Negative Sequence IOC:

Positive Sequence Restrained Negative

Sequence IOC:

K1 = 1/8 for negative sequence IOCK1 = 1/16 for zero sequence IOC

PICKUPI 2

PICKUPIKI 112

F60 Feeder Relay: Negative Sequence Directional Element



137/139



forward and reverse looking IOC

Independent settings for the forward and reverse

elements

Mixed operating mode available:

Negative Sequence IOC / Negative Sequence

Directional

Zero Sequence IOC / Negative Sequence Directional

Energy based comparator and positive sequence

restraint


138/139



139/139

ur protect

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