ZLV

1© ZIV Aplicaciones y Tecnología S. A.

Distance Protection


PROTECTION FUNCTIONS

Function Description21+21N Distance protection for phase and ground faults

50Sup Overcurrent for distance monitoring

Load encroachment logic

Protection schemes for distance elements

Fuse failure detector

Close onto fault logic

Remote breaker open detector

Dead Line Detector

68/78 Power swing blocking and/or tripping (out of step t ripping)

25 Synchronism check

79 3-pole/1-pole recloser

50BF Breaker failure protection


Function Description46 Open phase detector

49 Thermal image protection

50F Three phase instantaneous overcurrent elements (A,B ,C)

50N Three ground instantaneous overcurrent elements

50Q Three negative sequence instantaneous elements

51F Three phase time delay overcurrent elements (A,B,C)

51N Three ground time delay overcurrent elements

51Q Three negative sequence time delay overcurrent elem ents

67 Phase directional unit (A,B,C)

67N Ground directional unit

67Q Negative sequence directional unit

Protection schemes for 67N/67Q



Function Description50STUB Stub bus protection

59 Three phase overvoltage elements (A,B,C)

27 Three phase undervoltage elements (A,B,C)

59N Two ground overvoltage elements

81M Three overfrequency elements

81m Three underfrequency elements

81D Three rate of frequency change elements

Single/three pole tripping for 21+21N and 67N/67Q

Suitable for cables and overheadlines with series capacitor compensation

Mutual coupling compensation for parallel lines



DescriptionBreaker supervision

Fault locator (compensates for load flow and mutual coupling)

Trip masks for distance zones or for auxiliary units

Programmable logic (executed each 2 ms)

Oscillography with analog and digital signals

Records: events, fault reports and metering logs

Measurement

Control

Communications

User interface (alphanumeric display and keypad/pro grammable push bottons for operations or commands)

Integrated simulator

ADITIONAL FUNCTIONS


4 x V + 5 x I ó 5 x V + 8 x I (depending on the mod el)

1 alarm output (watchdog)

Digital inputs (all programmable):

10 in 2 U box

22 in 3 U box

34 in 4 U box

37 in 6 U box

Outputs (all programmable and strong: anyone can be used as trip / close output)

10 in 2 U box (4 can be fast for teleprotection)




Connectors with ring lugs

INPUTS / OUTPUTS


5 distance zones (all reversible)

6 independent measuring elements for each zone

Impedance reaches, resistive reaches and time delay s independent for ground and phase units

Selectable characteristic independent for phase and ground faults:

Mho (dynamic and variable)

Quadrilateral

Both combined (AND / OR)

Reaches (Z1) and zero sequence compensation factors (K0=Z0/Z1) independent for each zone in module and a ngle

DISTANCE PROTECTION


Dynamic characteristic (memory action):

Variable characteristic (V1 action):

Advantages of polarizing with V1M:

Proper operation for zero voltage three phase faults and for voltage inversions (series compensation)

Proper operation for zero voltage single phase and two-phase faults

MHO CHARACTERISTIC


ZSLESL ZL

V1IX ⋅⋅⋅⋅

IR⋅⋅⋅⋅

IZSL⋅⋅⋅⋅

IX ⋅⋅⋅⋅

IR⋅⋅⋅⋅

IZLZSR ⋅⋅⋅⋅++++ )(

V1F1

ZSR

F2

IF2

V2

IF1

F1

IrelayIF2F2V1

IF1=Irelay

F1V1F2V2

-jXC

MHO CHARACTERISTIC


V

φ

Ieq1

V

φ

1M

IX ⋅

IR ⋅)( cargaIIeqZSL φ−⋅

111 ZIeq ⋅

RFIF ⋅F F’

I

1M

IX ⋅

IR ⋅

F F’

Vφ φ

Vφ φ

φ φ

)( cargaIIZSL φφφφ −⋅

2

RFIF ⋅φφ

Z11⋅Iφφ

PHASE-GROUND FAULTS [ ] φφ VnZnKIIFop −⋅−⋅+= 1)10(0

MVFpol 1φ=

( ) ( )[ ] 90ºFpolargFopargº90 ≤−≤−

PHASE-PHASE FAULTSφφφφ VnZIFop −⋅= 1

MVFpol 1φφ=

MHO CHARACTERISTIC


QUADRILATERAL CHARACTERISTIC

θθθθ1

Zr

Directional unit

Reactance element (load and non homogeneity compensation)

Resistive limiters


REACTANCE ELEMENT

SINGLE PHASE TO GROUND FAULT

Z1SL Z1SRESLA ESRA

Z1SL Z1SRESLB ESRB

Z1SL Z1SRESLC ESRC

ZSN ZSN’ZN

Z1LF Z1LF’

Z1LF Z1LF’

Z1LF Z1LF’

ZN’

Ic

Ib

Ia

Ic’

Ib’

Ia’IFa

RF

RFIFaLFZIeqVa ⋅+⋅= 1 ( )100 −⋅+= KIIaIeq

VaVbVc


PHASE-PHASE (TO GROUND) FAULT

2/1 RFIFabLFZIeqVab ⋅+⋅= IbIaIabIeq −==

Z1SL Z1SRESLA ESRA

Z1SL Z1SRESLB ESRB

Z1SL Z1SRESLC ESRC

Z1LF Z1LF’

Z1LF Z1LF’

Z1LF Z1LF’

Ic

Ib

Ia

Ic’

Ib’

Ia’

VaVbVc

RF/2

RF/2 RgIFb

IFa

IFbIFaIFab −=

REACTANCE ELEMENT


IF RF⋅

VrIeq Z LF⋅ 1

Ieq

αααα

Z1FIeq ⋅IX ⋅

IR ⋅

RFIFLFZIeqVr ⋅+⋅= 1 RFIeq

IFLFZZr ⋅+= 1

ZrZ1LF

ααααZ1FX

R

RFIeq

IF ⋅ Fr

F

ERROR

F

Fr

REACTANCE ELEMENT


α α α α depends onLOAD FLOW

HOMOGENEITY

0≈αLOAD FLOW AND HOMOGENEOUS SYSTEM

FORWARD LOAD FLOW 0<αREVERSE LOAD FLOW 0>α

NO LOAD FLOW AND NON HOMOGENOUS SYSTEM

NO LOAD FLOW AND HOMOGENOUS SYSTEM

REACTANCE ELEMENT

( )Z1LF Z1SLα arg

Z1L Z1SL Z1SR

+=

+ +


LOAD FLOW AND HOMOGENOUS SYSTEM

F

Z1F

α

Fr

ZrZ1LF

R

X

Underreaching effect ( α>0) Overreaching effect ( α<0)

F

Z1F Fr

Zr

Z1LF

R

X

RFIeq

IF ⋅RF

Ieq

IF ⋅α

Ieq

Fpol

Avoid

Ieq

Fpol

Avoid

Fpol parallel to IF

2φIFpol =

pfIIFpol φφφφ −=

Single line to ground fault

Phase-phase fault (with or without ground)

pfIIFpol φφ −=

REACTANCE ELEMENT


NO LOAD FLOW AND NON HOMOGENOUS SYSTEM

Fpol NON parallel to IF (angle= α)

Faults at 100% γ = α

Zr

Z1LF

α

Z1F

X

R

RFIeq

IF ⋅

Ieq

Fpol

F

Fr

REACTANCE ELEMENT

( )Z1LF Z1SLα arg

Z1L Z1SL Z1SR

+=

+ +

γ

Tilting angle is introduced

( )Z1L Z1SLarg

Z1L Z1SL Z1SRγ

+=

+ +


⋅

Ieq1

Z11

α C1

C2

Fpol

Vφ

F

F’

α

⋅Ieq1

I φ

IX ⋅

IR ⋅

RF⋅IF

FopZ11

αC1

C2

Fpol

V

F

F’

α

⋅

I

φφI

φφ

φφ

IX ⋅

IR ⋅

Fop

2/IF RF⋅φφ

[ ] φφ VnZnKIIFop −⋅−⋅+= 1)10(0 φφφφ VnZIFop −⋅= 1

2φIFpol = pfIIFpol φφ −= pfIIFpol φφφφ −=

REACTANCE ELEMENT

PHASE-GROUND FAULTS PHASE-PHASE FAULTS

( ) ( )[ ] 180ºFpolargFoparg0 ≤−−≤ γ


Dynamic line (memory action):

Variable line (V1 action):

Advantages of polarizing with V1M:

Proper operation for zero voltage three phase faults and for voltage inversions (series compensation)

Proper operation for zero voltage single phase and two-phase faults

DIRECTIONAL UNIT


IX ⋅⋅⋅⋅

IR ⋅⋅⋅⋅

DIRECTIONAL UNIT

IX ⋅⋅⋅⋅

IR⋅⋅⋅⋅V1F1 IrelayIF2

F2V1

IF1=Irelay

F1V1 F2V2

IZSL⋅⋅⋅⋅

IZLZSR ⋅⋅⋅⋅++++ )(

ZSLESL ZL

V1

ZSR

F2

IF2

IF1

F1

-jXC

V2


( ) ( ) ( )[ ] ( )αα −≤−≤+− º90argargº90 FpolFop

DIRECTIONAL UNIT


V

φ

Iφ

V

φ

1M

Iφ

IX ⋅

IR ⋅

α

)( cargaIIeqZSL φ−⋅

C3

F

V

I

V 1M

I

IX ⋅

IR ⋅

α

φ φ

φ φ

φ φ

φ φ

)( cargaIIZSL φφφφ −⋅

C3

F

φIFop= φφIFop=MVFpol 1φ= MVFpol 1φφ=


φφ VRGnIFop −⋅= RGnIFpol ⋅= φ φφφφ VRPnIFop −⋅= RPnIFpol ⋅= φφ

[ ])arg()arg( IeqnInbucle −−== φθθθ nθθ =

RESISTIVE LIMITER


C4

V

F’

Z11⋅Ieq1

Ieq1

φ

IX ⋅

IR ⋅

F

Iφ

11θ

1bucθ

RFIF ⋅

1RGI ⋅φ

C4

V

F’Z11⋅

I

IX ⋅

IR ⋅

F

11θ

φφ

φφ

Iφφ 2

RFIF ⋅φφ

1RPI ⋅φφ

( ) ( ) ( )[ ] θθ ≤−≤+− FpolFop argargº90


QUADRILATERAL: PHASE-GROUND FAULTS


QUADRILATERAL: PHASE-PHASE FAULTS


Based on angle between Ia2 and Ia1 fault currents

For faults with zero sequence infeed uses phase undervoltage units

Allows:

Single pole tripping on single-phase-ground faults

Blocking leading phase on phase-phase-ground faults

For phase-phase-ground faults the lagging phase-ear th loop can not be blocked: helps phase-phase loop in some kind of faults

PHASE SELECTOR


( ) ( )f_1Iaarg2Iaarg −=φ

InIa ⋅> 05.02 %101

2 >Ia

IaInIa ⋅> 05.00 %8

1

0 >Ia

Ia

PHASE-PHASE FAULT GROUND FAULT

PHASE SELECTOR


PHASE-PHASE-GROUND FAULTS

Z1LF

Z1LF

RF

Rg

IFbIFa

RF

IFT

A

B

ZN

Va Vb

Ib

Ia

Z1LF

Z1LF

RF

IFbIFa

RF

IFT

A

B

ZN

Va Vb

Ib

Ia

ABG FAULT:AG unit overreachesBG unit underreaches

AG BG FAULT:AG and BG units operate correctly

The AB unit can be complemented with the BG unit


FAULT DETECTOR

Sequence currents increment detection ( ∆I0, ∆Ia1, ∆Ia2)

Sequence currents levels exceeded (I0, Ia2)

Sealed-in by operation of distance units, overcurre nt units, close onto fault detector and stub bus protection

Supervises the tripping produced by distance units, overcurrent units, close onto fault detector, stub bus protection and remote breaker open detector

Determines the fault inception time (allows the sel ection of prefault and postfault values: current and voltage)


FAULT DETECTOR


α1α1α1α1α2α2α2α2

R1R2

X

R

R: minimum Rloadα: minimum PF

LOAD ENCROACHMENT


Activation when:

Phase undervoltage units pick-up without

activation of fault detector

Input coming from MCB activates

Inhibited when any pole is open

Can block distance elements, weak infeed trip,

synchronism, dead line detector and voltage units

FUSE FAILURE DETECTOR


FUSE FAILURE DETECTOR


Detects what pole of the breaker has opened

Detection based on breaker contacts plus undercurre nt

detectors

Outputs used by phase selector, distance units, fau lt

detector, power swing detector, fuse failure detect or,

ground and negative sequence overcurrent units, rec loser,

etc

OPEN POLE DETECTOR


OPEN POLE DETECTOR


OPEN POLE DETECTOR


DISTANCE UNITS OPERATION

SINGLE PHASE UNITS


DISTANCE UNITS OPERATION

PHASE-PHASE UNITS


DEAD LINE DETECTOR

Operated based on undervoltage and undercurrent uni ts

Only applicable when the VT is on the line side

Allows detecting the breaker closing without the ne ed from

external contacts

Can be used to activate the close onto fault functi on


Activated with manual close or reclose commands:

internal or external

Phase overcurrent units with second harmonic

restraint ( inrush stabilization)

Zone 1 extension:

Always activated for close commands

Adjustable for reclose commands

CLOSE ONTO FAULT DETECTOR


CLOSE ONTO FAULT DETECTOR


X

R

Stable oscillation

Unstable oscillation

A

ZONE INT

ZONE MED

ZONE EXT

δ

ZB

ZA

ZL

Slow trip

Fast trip

T

POWER SWING DETECTOR


Selectable zones to be blocked

Unblocking of blocked distance zones when a fault is

detected:

Ground or phase-phase fault detection (phase select or)

Time the impedance remain inside the external zone

Tripping for unstable swings: slow/fast trip





Basic Scheme:

Stepped distance

Schemes without communication channel:

Zone 1 extension

Remote breaker open detector

DISTANCE PROTECTION SCHEMES


Schemes with communication channel:

Permissive underreach transfer trip ( PUTT)

Direct transfer trip ( DTT)

Permissive overreach transfer trip ( POTT)

Directional comparison unblocking ( DCUB)

Directional comparison blocking ( DCB)

User defined (programmable logic)

Binary information transmission (virtual inputs/out puts)




Complementary logics:

Echo and weak infeed trip logic

Transient blocking for current reversal (parallel lines)


STEPPED DISTANCE

Independent timers for phase and ground faults

Timers do not drop out for evolving faults

Blocking signals coming from:

Power swing detector

Fuse failure detector

Series compensated lines logic


STEPPED DISTANCE


ZONE 1 EXTENSION

Zone 1 extended to overreaching zone (zone 2 or 3)

Requires fast reclosing to restore the supply as fa st as

possible

Inhibited when the breaker opens; enabled again whe n

the breaker remains closed for a settable time

Avoids zone 1 extension when reclosing


ZONE 1 EXTENSION


PUTT

Carrier sending by zone 1 (underreaching)

Settable carrier time

Can be complemented by weak infeed logic (trip)

Optional carrier sending by open breaker



Digital input


PUTT


DTTSimilar to PUTT but with direct trip by carrier rec eption


Settable security time to avoid erroneous operation s

due to noise in the communication channel



Power swing detector (only blocks carrier sending)

Digital input


DTT


POTTCarrier sending by overreaching zone


Can be complemented by weak infeed (echo or

echo+trip) and current reversal logics




Digital input


POTT


DCUBSimilar to POTT but allows instantaneous tripping f or a

time window (150 ms) even if the carrier is lost

Requires frequency-shifted PLC equipment


Can be complemented by weak infeed (echo or echo+tr ip) and current reversal logics




Digital input


DCUB


DCBCarrier sending by reverse zone (zone 4 or zone 5) or non-

directional overcurrent units (fast carrier sending )

Settable time delay for overreaching zone operation

Implicit current reversal logic

Carrier stop input / output

Blocking signals (inhibite tripping and generate ca rrier) coming from:


Digital input


DCB


WEAK INFEED LOGIC

Selectable logic output: NON, ECHO or ECHO+TRIP

Settable security time to avoid erroneous echo send ings

due to noise in the communication channel

Implicit current reversal logic

Settable voltage threshold for weak infeed trip

Phase selector based on undervoltage units

Optional weak infeed trip blocking by fuse failure detector


WEAK INFEED LOGIC


CURRENT REVERSAL LOGIC

Can be applied in any permissive overreaching schem e

Blocking signal for overreaching zone is activated b y

reverse zone (zone 4 or zone 5) pick-up

Settable blocking time delay


CURRENT REVERSAL LOGIC


REMOTE BREAKER OPEN DETECTOR

Allows zone 2 instantaneous tripping once the remote

breaker is detected as open (three-phase):

Loss of load (undercurrent detectors)

Capacitive current detection (long lines)

( ) ( ) ( )[ ] ( )δφφδ +≤−≤− º90argargº90 VI


REMOTE BREAKER OPEN DETECTOR


OVERCURRENT UNITSPhase, ground and negative sequence / instantaneous and

time delayed

Selectable torque control: non-directional / forwar d / reverse

Selectable directional unit (torque control type)

Torque control disable input

Time delay reset input


Digital input

Open pole detectors (ground and negative sequence units)

Series compensated lines logic


PHASE INSTANTANEOUS

OVERCURRENT UNITS


GROUND INSTANTANEOUS

OVERCURRENT UNITS


NEGATIVE SEQUENCE

INSTANTANEOUS OVERCURRENT UNITS


PHASE TIME-DELAYED

OVERCURRENT UNITS


GROUND TIME-DELAYED

OVERCURRENT UNITS


NEGATIVE SEQUENCE

TIME-DELAYED OVERCURRENT UNITS


Phase directional units:

Polarized by quadrature memory phase-phase voltage

Ground directional units:

Polarized by zero-sequence voltage

Polarized by current coming from an earth clamp

Negative sequence directional units:

Polarized by negative sequence voltage

Distance zone 2 can act as directional unit for o/c

Two setting options available in case of loss of po larization (can be applied to fuse failure ): blocking/permission

DIRECTIONAL UNITS


DIRECTIONAL UNITS


Polarization voltage compensator factor for ground and negative sequence directional units:

)67_00(_ 67_67 NANGKIVPOLF NCOMPN ∠⋅+−=

)67_22(_ 67_67 QANGKIVPOLF QCOMPQ ∠⋅+−=

Applications:

Increase polarization voltage: makes it higher than minimum level for polarization (strong zero/negative sequence sources)

Invert polarization voltage: compensates inversions in series compensated lines

DIRECTIONAL UNITS


ZA0 ZB0p x ZL0 (1-p) x ZL0

IF

I0

V0

ZA0 ZB0 ZL0

IF

I0

V0

-V0

I0

COMP_67NKI0 ⋅ ANG_67N

Forward

Reverse

)0(00 IZAV −⋅= 0)00(0 IZBZLV ⋅+=Forward fault Reverse fault

DIRECTIONAL UNITS


jXSL2 jmXL2-jXC

j(1-m)XL2 jXSR2

V2

I2 IF

I2

)2(22 jXCjXSLIV −−−−⋅⋅⋅⋅====−−−−

22 jXSLI ⋅⋅⋅⋅

)(2 jXCI −−−−⋅⋅⋅⋅

QCOMPKI 67_2 ⋅⋅⋅⋅FORWARD FAULT

Negative sequence voltage inversion if, with line side CT : XC>XSL2

Vpolarization CompensationXCK QCOMP >>>>67_

DIRECTIONAL UNITS


jXSL2 jXL2-jXC

jXSR2

V2

I2IF

REVERSE FAULT

I2

)22(22 jXSRjXLIV ++++⋅⋅⋅⋅====−−−−

QCOMPKI 67_2 ⋅⋅⋅⋅

¡Attention with reverse faults!: do not overcompensate Vpolarization

2267_ XSRXLK QCOMP ++++<<<<

DIRECTIONAL UNITS


For ground or negative sequence directional O/C (67 N/67Q)

Permissive underreach transfer trip (PUTT)

Direct transfer trip (DTT)

Permissive overreach transfer trip (POTT)

Directional comparison unblocking (DCUB)

Directional comparison blocking (DCB)

User defined (programmable logic)

Echo and week infeed tripping

Transient blocking for current reversal

O/C PROTECTION SCHEMES


OPEN PHASE DETECTOROnly operates with series faults (broken conductor)

Independent from load current (I2/I1 ratio)


Includes logic to check voltages on both sides of t he breaker. Setting options that allow reclose or manu al close:

Dead line/live bus

Live line/dead bus

Dead line/dead bus

In case of live line/live bus three conditions can be checked:

Voltage magnitudes difference

Voltage angles difference

Frequency difference

Compensation for the breaker closing time

Synchronism for two breakers

SYNCHROCHECK UNIT


SYNCHROCHECK UNIT


Current detection levels and timers are independent for single and three phase trips

Breaker failure pick ups initiated by single pole t rips include phase segregated current detectors and time rs

Non overcurrent breaker failure detection ( trips from overvoltage, frequency, Buchholz etc)

Retrip command (single/three phase)

Initiation by external protection trip: single/thre e pole

Breaker arc detection

Supervision of two breakers

BREAKER FAILURE


BREAKER FAILURE


TRIP LOGIC

Can trip single pole for a single phase to ground f ault with:

Any distance zone

Accelarated overreaching zone

Instantaneous ground or negative sequence unit 1

Accelarated overreaching overcurrent units

Includes the following inputs:

Programmable trip

Trip Blocking

Pole n (n=A, B, C) trip blocking

Three pole trip preparation blocking


RECLOSER

Single/three pole reclose

4 reclosing modes: 1p, 3p, 1p/3p and dependent

Up to three reclose cycles

Can operate with external protections

Internal or external synchronism check

Programmable recloser initiation masks

Can control two breakers

Independent timers for single and three pole recloses


RECLOSER


Breaker supervision:

Excessive number of trips

Maintenance (accumulated kA 2)

Supervision of trip and/or close circuits (up to 6)

Pole discrepancy detector

SUPERVISION


BREAKER AND A HALF FUNCTIONALITY

B1

B2

L1

52-1

52-2

I1

I2

ILÍNE=I1+I2

L2

IA2 IB2 IC2

IA1 IB1 IC1VA VB VC

VSINC2

VSINC1


Programmable directional unit

Stub bus protection more secure for CT saturation

2 breaker failure units

2 synchrocheck units

2 coordinated reclosers

Supervision (accumulated kA N) for 2 breakers

BREAKER AND A HALF FUNCTIONALITY


CT-2

CT-1

WEAK SOURCE

STRONG SOURCE

I-2

I-LINEI-1

Directional unit more stable for CT saturation duri ng external faults (created with the programmable logic)

I-2 I-1

I-LINE

WITHOUT CT-1 SATURATION

NEW DIRECTIONAL UNIT

-90º<arg(I-1)-arg(I-2)<90º

ZL

I-2 I-1

I-LINE

WITH CT-1 SATURATION

NEW DIRECTIONAL UNIT


TI-2

TI-1

I-2

I-1

STUB BUS PROTECTION

89-L1

L1

WITHOUT CT SATURATION: I LINE=0

WITH CT SATURATION: I LINE≠0

2

21 −+− II

LÍNEAI

IMINα

Overcurrent unit only in operation when the line is olator opens

Retraint by through –fault current

ZONA DE OPERACIÓN

ZONA DE NO OPERACIÓN


BREAKER FAILURE

B1

B2

L1

52-1

52-2

I1

I2

L2

52-3

52-1 failure

B1 Open and intertrip

Detection with I1

52-2 failure

52-3 open and intertrip

Detection with I2


SYNCHROCHECK UNIT

Position 89-2

89-1

89-2

B1

B2

L1

L2

B1

B2

89-B1 89-B2

Position 89-B1 Position 89-B2

Breaker and a half Double busbar

52-B1

52-B2

52-0 52

VA VB VC

VSINC2

VSINC1

VSINC1 VSINC2

VA VB VC IN-1 IN-2


RECLOSER

Possibility for sequencial reclosing to avoid closing onto fault both breakers

Selection of the master and slave reclosers

Permission / blocking of the slave recloser when the master one is blocked

Blocking of the recloser associated to a manually open breaker

B1

B2

L1

52-1

52-2

I1

I2

L2

52-3

Documents

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