Phased Refurbishment of Relays and Communication Channels

1G. Koch D Session 3 – Block 3 – paper 3.68 update

Barcelona 12-15 May 2003

Traditional panel with analogue relays and traditional control

Modern panel with numerical multi-function relay

Phased Refurbishment of Relays and Communication Channels



DCE DCE

DCE DCERM

RM

RR

DCE DCERM

RM

DCE DCERM

RM

Dedicated channel

FO shared

shared channel

non-switched channel

switched, time sharedpacket switching suitable?

Transportation network

DCE DCE MM

DCE DCE

WDM WDM

R R

Communication Channel Options



2 Options

A/D D/A

87L 87L

Digital channel

Digital channel

87L87L

Digital relay Digital relay

Analogue relay Analogue relay



%

I

O

V

0 50 100

Legend:DCE digital communication equipmentSCM supervisory control mimicR2R relay-to-relay comsR2S relay-to-subscriber coms

One feeder, one IED!

Protection

Metering

Control

Fee

der

dat

a b

ase

DCE

SCM

DCE R2R

R2S

Remote Interrogation and Data Acquisition for DMS



Bay Data publishingBay Data publishing

Enterprise subscribersEnterprise subscribers

Content providerRelay orbay controllerwith embeddedWEB server

Continuous event-driven inquiry

load data fault reports set points status indication

dynamic data static data

Web clients Relay engineermaintenance staff etc.

Ethernet TCP/ IP

Substation Substation

Router

Intra net

mobile

WEB Publishing



Scope of Functions

Channel to remote endLegend : 87L Differential relay50/51 Back-up overcurrent49 Thermal overload 85 Intertrip channels86 Lock-outFR Fault Recording MemoryM MeteringFC/SI Supervisory feeder controlRA Remote access (e.g. intranet)

508587L 51 49 79

86MFR FC SI RA

Option



87/49 87

FO

BH

Teleprotection and intertrip channel

Some 100m



87L 87L

EO

OE

EO

OE

EO

OE

Digital Coms network

ISDN

Optical fibres

Pilot wires

Optional communication media

Optional Communications Media



Latency, slot time (not necessarily data rate) latency band ( min. to max.), differential latency, critical net load, Propagation time Propagation time differential

dependability, Bit Error Rate BER BER for : <1 min, <1 sec, non-available if BER >10-3 for >10sec BER under fault conditions? measurement within time windows <100ms loss-of-channel, hot stand-by, back-up routes Route switching may cause nuisance alarm of relay monitor hostile environment, EMC, IEC 255

security inherent measures, e. g. permissive signals protocol security

Digital SDH-Communication- network

eoMuxMux

oe

oe

‘Quality of Supply, QoS’

G. Koch D Session 3 – Block 3 – paper 3.68 update


Induced Voltage along a Pilot Wire Pair

Legend

I earth fault current

0 flux generated by E/F - current

V induced voltage

V2

V1

V

V

I = fault current

V

2V

2

barrier transformer

E = 2f • M •I •L • r1 • r2



Induced Voltage, Calculation Example

Legendf frequency f = 50 HzM induction between power and pilot cable per km,

for a distance of 80 cm between cable and pilot wires,and for an earth conductivity of 0.02 s/m

e.g. M = 1.347 mH/kmI earth-fault current e.g. I = 15 kAL length of parallel running cables

e.g. l = 8.4 kmr1 reduction factor of h.v. cable

r1 = 0.2 - 0.4 for single conductor oil cablese.g. r1 = 0.3

r1 0.1 for cables in steel pipesr2 reduction factor of pilot cable

r2 = 1 for unscreened cablesr2 0.4 for best screening

e.g. r2 = 0.4

E = 2 f M r1 I L r2

E = 2 50 L / s 1.347 m s / km 15 kA 8.4km 0 3 0 4. .

E = .4 kV6



20 kV 500 V

relay panelpilot cablesealing end

barrier transformer prevents'dirty potential' to enter the relay panel

Galvanic Separation of Pilot Wire and Relay Potential

'dirty potential' 'clean potential'

Documents

Phased Refurbishment of Relays and Communication Channels