Protection coupler learning 8.3.13.pdf

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there is a woman……

Thanks to the woman behind me……….

who is my biggest critic, cheer leader,

support, guide & friend.

PLCC Protection coupler

Basic Concepts & Demonstration

S.V. Kulkarni DyEE PLCC MSETCL Pune

PLCC Protection coupler• Visit to Learning center PLCC 30 min

• PLCC introduction 15 min.

• PLCT 15 min.

• PLCC outdoor equipment 15 min.

• Coupling schemes 15 min.

• Tea Break 15 min

• Conventional & CAP 15 min.

• NSD 50 Transmitter & Receiver 15 min.

• G4AA G4AC 15 min.

• QA 15 min.

• Protection coupler demo 30 min.

To communicate is Human Nature

• We communicate to

–Convey feelings.

–Express

agreements.

–Express love.

–Learn/ Teach

–Share knowledge

–Communico (Latin)

PLCC & OPGW

The PLCC is a technology which uses power line

as physical media for speech, Data & protection

signal transmission.

PLCC Network

ExerciseLook at the pictures & write their names

PLCC Indoor & Outdoor equipment

Power Line Carrier Terminal• PLCT converts a input signal of 4 KHz bandwidth to the RF signal &

amplifies this signal to the desired output power levels up to 40

watts.

• The RF range in PLCC system is 50 KHz to 500 KHz

Modulation & Demodulation

• Modulation is a technique used to convert a low

freq signal( information signal) to a higher freq

signal ( modulated signal) using high freq signal

(carrier)

• Demodulation is the opposite technique where

information signal is extracted from the carrier.

• Modulation & Demodulation requires Carrier

frequency which is generated in PLCT.

PLCC Panel ( type: ABB ETL

41/42)

CabinetModules

( 428/456 U KHz)

Or (96/92 U KHz)

( 232/108 UL KHz)

Or 480/ 488 UL KHz

RxTxRx TxRx Tx

Frequency space

4 + 4 = 8 KHz required

Frequency space

4 + 4 +4 +4 = 16 KHz required

Telephone Bandwidth

•1000 Hz

•2000 Hz

•3000 Hz

•4000 Hz

•5000 Hz

•6000 Hz

Human voice 4 KHz, Music 15 KHz, TV 6 MHz BW

Single Channel

ABB Make ETL 41

PLCC Panel

( 96/92 U KHz)

Twin Channel

ABB Make ETL 42

PLCC Panel

( 480/488 UL KHz)

Tx band – 96-100 KHz

Rx band – 92- 96 KHz

Tx band – 476-480 K

Rx band- 484-488 K

Tx band – 480-484 K

Rx band- 488-492 K

Rx Tx RxTx RxTxFrequency Spectrum

U KHz

U KHz

L KHz

BW 4+4= 8 KHz BW 4 + 4 + 4 + 4 =16KHz

Adjacent FrequencyAdjacent Frequency

Single Channel

ABB Make ETL 41

PLCC Panel

( 428/456 U KHz)

Twin Channel

ABB Make ETL 42

PLCC Panel

( 232/108 UL KHz)

Tx band – 428-432 KHz

Rx band – 456-460 KHz

Tx band – 228-232 K

Rx band- 104-108 K

Tx band – 232-236 K

Rx band- 108-112 K

RxTx Rx TxRx TxFrequency Spectrum

U KHz

U KHz

L KHz

BW 4+4= 8 KHz BW 4 + 4 + 4 + 4 =16KHz

Separate FrequencySeparate Frequency

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Tx

/

Rx

Single channel Maximum 56 no. of PLCC panels for 50 to 500 KHz range

Tx/Rx I

Tx/Rx II

Tx/Rx I

Tx/Rx II

Tx/Rx I

Tx/Rx II

Tx/Rx I

Tx/Rx II

Tx/Rx I

Tx/Rx II

Tx/Rx I

Tx/Rx II

Tx/Rx I

Tx/Rx II

Tx/Rx I

Tx/Rx II

Tx/Rx I

Tx/Rx II

Tx/Rx I

Tx/Rx II

Tx/Rx I

Tx/Rx II

Tx/Rx I

Tx/Rx II

Tx/Rx I

Tx/Rx II

Tx/Rx I

Tx/Rx II

Tx/Rx I

Tx/Rx II

Tx/Rx I

Tx/Rx II

Tx/Rx I

Tx/Rx II

Tx/Rx I

Tx/Rx II

Tx/Rx I

Tx/Rx II

Tx/Rx I

Tx/Rx II

Tx/Rx I

Tx/Rx II

Tx/Rx I

Tx/Rx II

Tx/Rx I

Tx/Rx II

Tx/Rx I

Tx/Rx II

Tx/Rx I

Tx/Rx II

Tx/Rx I

Tx/Rx II

Tx/Rx I

Tx/Rx II

Tx/Rx I

Tx/Rx II

Twin channel Maximum 28 no. of PLCC panels for 50 to 500 KHz range

AM signal

fm fc

fc + fm

fc - fm

fc

Modulating signal

Speech

Data

Protection

Carrier Amplitude Modulated Signal

fm1 fc

fc

Modulating signal

Speech

Data

Protection

Carrier Amplitude Modulated Signal

fm2

Channel I Input signal

Channel II Input signal

Carrier signal

Carrier signal

Lower Sideband f c – f m 1

Carrier & USB removed

Upper Sideband f c – f m 2

Carrier & LSB removed

R

x

T

x

R

x

T

x

Speech signal

Protection signal

Data Signal Carrier

Amplitude

Modulated

Signal

AM

signal

fm

fm

fm fc

fc + fm

fc - fm

fc

PLCC Applications

PLCC link

• PLCT are used as a pair one at each end

• Each PLCT is designated for a set of Tx & Rx freq.

• These freq may be Separate Or Adjacent.

• The corresponding PLCT at the other end will be

designated for the reverse value of Tx/Rx freq.

• The ch freq. will be either in 4 KHz or 8 KHz BW

depending upon single ch or Twin ch.

Protection

FrequencyGuard

Frequency

Pilot

Frequency

Data Freq. Dial Freq. Speech Freq.

Carrier

Frequency

Exercise

7. Data frequency band ______________________KHz

Exercise

Hints – 1. Make ,Type & Frequency of PLCT

2. Selection of Pass band of LMU

3. Selection of Blocking band of LMU

4. PLCC Phase to phase coupling

5. Main HF cable & HF loop connection.

Coupling schemes---Economic ,Engineering & common sense…

• Mode 1 coupling

• Center ph to Outer ph (No Mode 3)

• Center ph to Ground ( No mode 2)

• Outer ph to outer ph with Ground

return (No mode 2)

• Outer ph to Ground ( All 3 modes)

Inter circuit

Phase-to-Ground

LMU

Cc

LT

PLC

Cc

LMDU LMUPLC

Cc

LT

LT

Cc

LMDU LMUPLC

Cc

LT

LT

Phase-to-Phase

PLCC Coupling

Modal analysis• Modal analysis is a mathematical tool similar to

symmetrical components used for analyzing

unbalanced faults on three ph power system.

• It can be shown that no. of natural Nodes is

equal to the no. of conductors involved in the

propagation.

• For example, 3 nodes in the case of a single

circuit line with 2 earth wires earthed at each

tower.

• The ph conductor V or I can be resolved into 3

sets of natural mode components at any point on

a lossy, reflection free three ph line.

Mode distribution for a 3 ph line

Mode 1 is least attenuated & least frequency dependent

more frequency dependent & has more attenuation than Mode1

Mode 3 is the highest attenuated mode & is propagated on all 3 phases & returns via

the ground

Mode components for various

types of coupling

a) Center phase to Ground coupling

b) Outer phase to Ground coupling

c) Center to Outer Push Pull coupling

d) Outer to Outer Push push coupling

Protection

Substation A

Substation B

Zone 1 (A & B)Zone 1 (A)

Zone 2 (B)Zone 1 (B)

Zone 2 (A)

Line Fault …PUTT…Distance relay( 21), Main I, Main II

Conductor snapping

Tree fault

Bird faultIn case of 400 KV line, Main I & Main II are parallel commands.

M I ,M II should be operated simultaneously.

Substation A Substation B

Substation Fault…Direct Trip Protection

Over Voltage

LBB

Reactor Protection

Busbar

Hand trip 86ROV all commands are routed through 86ROV except

Hand trip

85 LO receive command is routed through 85LO

relay.

Conventional 3 Zone Protection

Distance

Relay 21

Distance

Relay 21

400 220

Z 1 0 0

Z 2 300 400

Z3 500 700

Carrier aided Protection

Distance

Relay 21

Distance

Relay 21

Protection

CouplerProtection

Coupler

Trip logic

Conventional & Carrier aided protection

Carrier Aided Protection

Carrier aided Protection

• In the absence of communication link,

the operation of End zone fault is

longer & auto reclosing is not possible.

• Carrier aided protection scheme is used

for simultaneous tripping of near & far end

circuit breakers

• Protection Coupler equipments can be

used along with PLCC terminals for Tele

protection requirements.

Relay Interface 2

Opto coupler

Solid state C

Alarm Contact

Opto coupler

Solid state C

Relay Interface 1

Opto coupler

Solid state C

Opto coupler

Solid state C

DSP Card

G4AAG4AC G4AC

Protection Coupler ABB Make NSD 50 (Full version)

Alarm Contact

Slot no. 10 Slot no. 15 Slot no. 21

DSP

Protection coupler

At S/s A

Opto coupler

Alarm Contact

Protection coupler

At S/s B

Solid state

Contact

Alarm Contact

85X

Distance

Relay 21

Protection coupler

At S/s A

Solid state

Contact

Alarm Contact

Protection coupler

At S/s B

Opto coupler

Alarm Contact

85X

Distance

Relay 21

Protection coupler

At S/s A

Opto coupler

Solid state

Contact

Alarm Contact

Protection coupler

At S/s B

Opto coupler

Solid state

Contact

Alarm Contact

85X85X

30X30X

Principle of operation

• Under normal conditions, i.e. when there is no fault in the line, guard frequency or frequencies G1 & G2 will be continuously transmitted through the PLC channel for monitoring the healthiness of the equipment.

• In the event of operation of protection due to fault the guard signals will be cut & corresponding trip signals will be transmitted in the Speech band.

• Speech & any other Data transmission are interrupted while the trip signals are being transmitted.

Relay

Interfac

e

1

G4AC

Slot no.

15

Relay

Interfac

e

2

G4AC

Slot no.

21

DSP

DA

DA

DA

C

DSP Module G4AA Slot no.10Start A

Tx Command A AF Tx

BOOST

Pilot

Tx Speech

Relay

Interfac

e

1

G4AC

Slot no.

15

Relay

Interfac

e

2

G4AC

Slot no.

21

DSP

DA

DA

DA

C

Alarm

Tx,Rx,COM 1,2

DSP Module G4AA Slot no.10

Rx command A

Rx aux O/P A

AF Rx

Rx Speech

AGC

ALARM

NSD 50 Transmitter & Receiver

• Transmitter

• Applying DC voltage to the input Tx command interrupts the Pilot /Guard signal.

• Tx Speech cut off.

• Protection coupler will generate trip frequency which will be fed to PLCC panel & Tx Counter increments.

• Receiver

• Continuously monitor guard signal.

• When found any trip frequency with absence of guardsignal, Rx Speech is interrupted & Rx counter increments.

• At the same time Rx command on the protection relay is activated.

NSD 50 Trip Frequencies

• Command A 872 Hz

• Command B 1090 Hz

• A & B Permissive Trip/ Uncoded Commands

• Command C 654 Hz / 1526 Hz

• Command D 654 Hz / 1745 Hz

• C &D Direct Trip / Coded Commands

• A,B,C & D Commands are transmitted in

Speech band

Transmission time ,Security & Dependability

• The Performance of a protection coupler is

assessed by means of three criteria.

• The Transmission time

• The Security ( Unwanted command probability)

• The Dependability ( Missing command probability)

Permissive & Direct • This scheme is used for protection of power line with

Distance relay.

• Tripping can only take place at the receiving end if a tripping signal is being received and local protection relay detects a fault.

• Transmission Time – 12ms

• Command Prolongation (Trip Extension) time- 20ms

• The tripping command from the protection coupler goes

directly to the circuit breaker.

• Transmission Time – 26 ms

• Command Prolongation time- 100 ms

ABB ETL 41 ABB ETL 41 ABB ETL 41ABB ETL 41 ABB ETL 41

Main I Main II Direct Trip Sp Dialing Sp Express

M I Own M II Own Direct trip Own

M I Parallel

M II Parallelv

Utilization of PLCC panels (3P+2S)

A AB B C

Modified Utilization (2P+2/1S)

ABB ETL 41 ABB ETL 41 ABB ETL 41ABB ETL 41

Channel I Channel II Speech Dialing

A AB B

M II Own Direct trip Own

v

v

v

M I Parallel

M II Parallel

Direct trip Parallel

Speech Express

C C

OR

ABB ETL 41 ABB ETL 42

A AB B

M II Own

v

v

v

M I Parallel

M II Parallel

Direct trip Parallel

C C

Channel I Channel II Speech Dialing/Express

Twin Channel Panel

M I Own

M I Own

Direct trip Own

ABB ETL 41

I/P Volt 125 V DC…250 V DC CA,CC,CG,CI

I/P Volt 48 V DC…110 V DC CB,CD,CH,CK

Trip signal A / C CE,CP,CF,CQ

Rack slot N15/ N21 CN / CO

Com Prol. A 5ms/20ms/100ms CR/CS/CT

Relay Interface 1 G4AC

Trip signal B / D CL,CU,CM,CV

Com Prol. B 5ms/20ms/100ms CW/CX/CY

Stand-by Battery ON/OFF BA / BB

[ x ] (1)

[ x ] (2)

[ x ] (3)

[ x ] (4)

[ x ] (5)

[ x ] (6)

[ x ] (7)

[ x ] (8)

Programming DSP Switch S3 Command Settings

ON /OFF

Security : Step 2 (increased) / step 1

T03 nominal Transmission time T0 = 46 ms

T02 nominal Transmission time T0 = 26 ms

T01 nominal Transmission time T0 = 16 ms

Settings for Uncoded Tripping signals ( A,B)

Settings for Coded tripping signals (C,D)

Security : Step 2 (increased) / step 1

T03 nominal Transmission time T0 = 19 ms

T02 nominal Transmission time T0 = 12 ms

T01 nominal Transmission time T0 = 10 ms

[ x ] (1)

[ x ] (2)

[ x ] (3)

[ x ] (4)

[ x ] (5)

[ x ] (6)

[ x ] (7)

[ x ] (8)

Programming DSP Switch S4 Guard Setting

ON /OFF

Not used

Local Test ON / OFF

-10 dBm0 / -14 dBm0 unblocking threshold

200 Bd /100 Bd Pi filter

ETL Pilot / own guard

Setting of

Guard or Pilot Freq

(Default = 3780 Hz)

S4 (3) (2) (1) = pilot

0 0 0 = 3780 Hz

0 0 1 = 3600 Hz

0 1 0 = 3360 Hz

0 1 1 = 3120 Hz

1 0 0 = 2880 Hz

1 0 1 = 2640 Hz

1 1 0 = 2400 Hz

1 1 1 = 2160 Hz

[ x ] (1)

[ x ] (2)

[ x ] (3)

[ x ] (4)

[ x ] (5)

[ x ] (6)

[ x ] (7)

[ x ] (8)

Programming DSP Switch S5 Alarm Setting

ON /OFF

Not used

Not used

Interface in Slot N 21 ? Yes / No

Interface in Slot N 15 ? Yes / No

Command output latching status for

An alarm condition ( SNR/ Level Alarm)

S5 (4) (3) = statuses of the com O/P for an alarm

0 0 = no influence on receiver contacts

0 1 = uncoded tripped, coded contacts quiescent

1 0 = all receiver contacts quiescent.

1 1 = no influence on receiver contacts.

6 dB / 12 dB SNR alarm threshold

Cyclic loop test ON/ OFF

[ x ] (1)

[ x ] (2)

[ x ] (3)

[ x ] (4)

[ x ] (5)

[ x ] (6)

[ x ] (7)

[ x ] (8)

Programming DSP Switch S6 Alarm Delay

ON /OFF

27 6.5 s

26 3.3 s

25 1.6 s

20 0.05 s

21 0.1 s

22 0.2 s

23 0.4 s

24 0.8 sAlarm Relay delay =

Sum of ON values

(settings in steps of 50

ms)

Default setting = 10 s

Common alarm contacts ALARM 1, ALARM 2

Contact closes in alarm state ( N/C) AB,AD (default)

Contact opens in alarm state ( N/O) AA, AC

Signal Processor

Data & Program

MemoriesDigital

signals

Serial Interface

LEDs

Aux Alarm Relay

Tx command A

Start A

Tx command B

Start B

Rx command A

AUX A

Rx command B

AUX B

Unblocking 1

Unblocking 2

Relay Panel Protection coupler

Opto coupler

Solid state

Contact

Alarm Contact

Trip Send Contact in RP

Carrier Receive Relay in RP

Carrier Healthy relay in RP

85X

30X

RP K102

RP K877

RP K173

RP K169

RP K161

RP K169

Distance

Relay 21

Relay Panel Protection coupler

Opto coupler

Solid state C

Alarm Contact

Trip Send Contact in RP

CR relay in RP

Carrier Healthy relay in RP

85X

30X

Distance

Relay 21

Opto coupler

Solid state C

Trip Send Contact in RP

CR relay in RP

85X

Distance

Relay 21

WT WT

Relay PanelProtection coupler

Opto coupler

Solid state

Contact

Alarm Contact

Trip Send Contact in RP

Carrier Receive Relay in RP

Carrier Healthy relay in RP

85X

30X

RP K102

RP K877

RP K173

RP K169

RP K161

RP K169

21

Protection coupler

Opto coupler

Solid state

Contact

Alarm Contact

85X

30X

RP K102

RP K877

RP K173

RP K169

RP K161

RP K169

Relay Panel

Trip Send Contact in RP

Carrier Receive Relay in RP

Carrier Healthy relay in RP

21

ETL 41

PLCC

Panel

Having

Freq

84/80

KHz

with

NSD 50

ETL 41

PLCC

Panel

Having

Freq

80/84

KHz

with

NSD 50

M I

M II

DT

M I

M II

DT

84 + 0.872

=84.872 KHz

&

80 + 0.872

=80.872 KHz

Own Commands & Parallel commands

ETL 41

84/80

KHz

with

NSD

50

ETL 41

80/84

KHz

with

NSD

50

M I

M II

DT

M I

M II

DT

ETL 41

96/92

KHz

with

NSD

50

ETL 41

92/96

KHz

with

NSD

50

Exercise

Refer Fig A & B and Complete the following table

BPL DC 42 Protection Coupler• The DC 42 series Digital Protection coupler can be

directly inserted into the BPL Make 9505 V3 Power line carrier equipment.

• Under normal conditions i.e. when there is no fault in the line, two guard frequencies G1 & G2 will be continuously transmitted through the PLC channel for monitoring the healthiness of the equipment.

• When there is a fault the guard signals will be cut & corresponding trip signals will be transmitted in the speech band.

• Speech & any other Data transmission are interrupted while the Trip signals are being transmitted.

Guard & Trip frequencies of DC 42

• Guard 1- 2146 Hz

• Guard 2 – 2341 Hz

• Trip F1- 1171 Hz

• Trip F2 – 1366 Hz

• Trip F3 – 1561 Hz

• Trip F4 – 1756 Hz

• Trip F5 – 1951 Hz

• Loop Test Frequency – 3902 Hz

Block Diagram of DC 4

DC 42 Transmitter & Receiver When there is a fault, the trip signals will be extended to the

DC CPU through DC COMIO module.

The DC CPC sends the corresponding command to the DC REC module.

DC REC module decodes the command and corresponding frequency /frequencies are transmitted.

At the receiving end, the composite signals from the DC REC is fed to DC CPU module which detects the presence of trip signal ( only in absence of the guard signals ) & gives the corresponding command logic high /low & also logic lines corresponding to frequencies to DC CPU module.

DC CPU module decodes the logic lines and corresponding relays are activated.

The remote end breakers will be tripped only when the protection receiver depending on the nature of the fault receives the assigned combination of Trip frequencies.

•The DC PSU Module provides dual 12 V DC outputs & 5 V DC

output.

•DC CPU module provides the commands necessary to generate

the Guard & Trip frequencies.

•DC REC module is responsible for transmitting the frequency

corresponding to command issued by DC CPU as well detecting the

trip frequency and issuing corresponding trip command to DC CPU.

• DC COMIO consists of DC CIC & DC COC

•DC CIC provides the interface between the local distance protection

relays & protection relaying equipment.

•DC COC provides the necessary interface for transferring the trip

command received from the distant protection equipment to the local

distance protection relays.

Face plan of DC 42

Permissive & Direct Commands

• Command I – F1 + F3

• Command II – F2 + F4

• Command III – F5 F1 F5

• Command IV – F5 F2 F5

Permissive & Direct Commands

• The Transmission time permissive command is < 20 msec & for Direct command is < 30 msec.

• The trip frequency level is 11dB higher than guard frequency level in permissive & 17 dB higher in Direct scheme.

• The Direct commands are more secure whereas permissive commands are more dependable in nature.

Seek Excellence,

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