System Protection

Technical Specification for Volume Ⅱ-1

±660kV HVDC Project from Matiari to Lahore in Pakistan System Protection

TECHNICAL SPECIFICATION

FOR

±660kV HVDC PROJECT

FROM MATIARI TO LAHORE IN PAKISTAN

VOLUME Ⅱ-1

SYSTEM PROTECTION

CHINA ELECTRIC POWER EQUIPMENT AND TECHNOLOGY CO., LTD.

September 2015, Beijing, P.R. China



1

±660kV HVDC PROJECT

FROM MATIARI TO LAHORE IN PAKISTAN

GENERAL LIST OF CONTENTS

VOLUME I GENERAL REPORT

VOLUME II SECONDARY SYSTEM

Volume II-1 System Protection

Fig.Volume II-1-1 Single Line Diagram of 500kV Protection System of Matiari

Fig.Volume II-1-2 Single Line Diagram of 500kV Protection System of Lahore

Volume II-2 System Communication

Fig.Volume II-2-1 Schematic Diagram of System Communication Channel Assignment

Fig.Volume II-2-2 Configuration Diagram of System Communication Equipments

VOLUME III HVDC CONVERTER STATION

Volume III-1 Matiari Converter Station

Fig.Volume III-1-1 Single Line Diagram of Matiari Converter Station

Fig.Volume III-1-2 General Layout Diagram of Matiari Converter Station

Fig.Volume III-1-3 Site Location Plan Diagram of Matiari Converter Station

Fig.Volume III-1-4 Conceptual Configuration for Substation Automation System of Matiari

Fig.Volume III-1-5 Configuration Diagram of HVDC System Protection of Matiari

Volume III-2 Lahore Converter Station

Fig.Volume III-2-1 Single Line Diagram of Lahore Converter Station

Fig.Volume III-2-2 General Layout Diagram of Matiari Converter Station

Fig.Volume III-2-3 Site Location Plan Diagram of Matiari Converter Station

Fig.Volume III-2-4 Conceptual Configuration for Substation Automation System of Lahore

Fig.Volume III-2-5 Configuration Diagram of HVDC System Protection of Lahore

VOLUME IV HVDC TRANSMISSION LINE

Fig.Volume IV-1 Site Location Plan from Matiari to Lahore

Fig.Volume IV-2 Tower Outlines

Fig.Volume IV-3 Foundation Outlines

Annex Volume IV-1 Conductor Choice Report

VOLUME V ELECTRODE AND ELECTRODE LINE

Volume V-1 Electrode and Electrode Line of Matiari Converter Station

Volume V-2 Electrode and Electrode Line of Lahore Converter Station

VOLUME VI HVDC SYSTEM FUNCTIONAL SPECIFICATION

Annex Volume VI-1 System Losses

Annex Volume VI-2 System Reliability



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TECHNICAL DEFINITIONS

The following technical definitions apply to this Specification:

Purchaser National Transmission And Despatch Company Limited (NTDC)

Company The project company for development, investment, construction,

operation and maintenance of the ±660kV HVDC project from

Matiari to Lahore in Pakistan.

HVDC System All of the relevant equipments and systems in bipolar operation,

including converter transformers, convertor valves, DC yard

equipment, AC filter, control& protection system, DC transmission

line, electrode and electrode line, etc.

HVDC Project HVDC System and the relevant construction works in this project.

the relevant construction works including outlet and inlet line of

converter station, buildings and structures, related auxiliary

production facilities and living facilities.

M-L T/L Matiari-Lahore Transmission Line

AC yard AC switchgear area in converter station

DC yard DC switchgear area in converter station

Life yard Living facilities and part of auxiliary production facilities area in

converter station

T area Transformer area

M-E T/L Matiari Electrode Grouding Transmission Line

M E/G Matiari Electrode Grouding

L-E T/L Lahore Electrode Grouding Transmission Line

L E/G Lahore Electrode Grouding

M C/S Matiari Convertor Station

L C/S Lahore Convertor Station

M AC busbar Matiari AC busbar

L AC busbar Lahore AC busbar

M AC system Matiari AC system

L AC system Lahore AC system



3

P I Pole I

P II Pole II

The following abbreviations apply to this Specification:

AC Alternating Current

ACI American Concrete Institute

A/D Analog to Digital

AN Audible Noise

ANSI American National Standards Institute

ASCE American Society of Civil Engineers

ASTM American Society for Testing Material

BIL Basic Impulse Insulation Level

BS British Standard

BSL Basic Switching Impulse Insulation Level

CB Control Building

CCITT International Consultative Committee on Telephone and Telegraph Systems

CT Current Transformer

CTV Capacitive Voltage Transformer

D/A Digital to Analog

DC Direct Current

DIN Deutsches Institute fur Normung

EEI Edison Electric Institute

EIA Environmental Impact Assessment

ESCR Effective Short Circuit Ratio

ESDD Equivalent Salt Deposit Density

FAT Factory Acceptance Tests

HF High Frequency

HVDC High Voltage Direct Current

IEC International Electrotechnical Commission



4

IEEE Institute of Electrical and Electronics Engineers

I/O Input/Output

ISO International Standards Organization

LED Light Emitting Diode

MMI Man Machine Interface

MVU Multiple Valve Unit

NFPA National Fire Protection Association

OPGW Optical Fiber Composite Overhead Ground Wire

P&C Protection and Control

PLC Power-line Carrier

PT Potential Transformer

RF Radio Frequency

RI Radio Interference

RIV Radio Interference Voltage

RTU Remote Terminal Unit

RPC Reactive Power Controls

SCADA Supervisory Control and Data Acquisition

SER Sequence of Events Recorder

SLG Single Line to Ground Fault

SMC Station Master Clock

SPC Software Production Control

SWC Surge Withstand Capability

TFR Transient Fault Recorder

UPS Uninterruptible Power Supply

VDT Video Display Terminal

VDU Video Display Unit

VF Voice Frequency

VT Voltage Transformer



Volume Ⅱ-1 -i

VOLUME Ⅱ-1 CONTENTS

1. General ................................................................................................................ 1

1.1 Design Basis ............................................................................................................. 1

1.2 Project Overview ...................................................................................................... 1

1.3 Scope of Design ........................................................................................................ 1

2. Relay Protection and Security........................................................................... 2

2.1 Current Situations of Relay Protection ..................................................................... 2

2.2 Principles for Configuration of AC System Protection ............................................ 2

2.3 Configuration Scheme of Relay Protection .............................................................. 4

2.4 Basic Requirements for Protection Devices ............................................................. 5

3. System Dispatch Automation ............................................................................ 7

3.1 Dispatch Administrative Relations ........................................................................... 7

3.2 SCADA system Information ..................................................................................... 7

3.3 SCADA System Scheme ........................................................................................... 9

3.4 Energy Metering System .......................................................................................... 9



Volume Ⅱ-1 -1

1. General

1.1 Design Basis

(1) Program for Feasibility Study on ±660kV HVDC PROJECT FROM MATIARI

TO LAHORE IN PAKISTAN

(2) NTDCL Specification P-204:2008

1.2 Project Overview

It is planned to complete the two poles of ±660kV HVDC PROJECT FROM

MATIARI TO LAHORE IN PAKISTAN in 2017 which has a bipolar capacity of

4000MW for transmitting power from Matiari converter station to Lahore converter

station.

1.3 Scope of Design

The scope of design for the Project covers the AC system protection (including 500kV

AC transmission line protection, 500kV Busbar protection, 500kV Breaker Failure

protection， 500kV shunt reactor protection), dispatch automation, and energy

measurement system for Matiari and Lahore converter station systems.

DC protection and DC/AC filter protection will be considered in the secondary design

of electrical system.

NTDCL Specification P-204:2008 shall be followed for only 500kV AC transmission

line protection, 500kV Busbar protection, 500kV Breaker Failure protection, 500kV

shunt reactor protection. Other AC protection and control (including 500/35kV

step-down transformers protection, 35kV reactor protection , 35kV bus bar protection,

35 kV transformers protection, 10kV transformers protection, fault recorder, etc.) shall

not followed NTDCL Specification P-204:2008.



Volume Ⅱ-1 -2

2. Relay Protection and Security

2.1 Current Situations of Relay Protection

At present, the 500kV lines in Pakistan power grid are provided with distance

protection and multiplex carrier channels are used to transmit the protection

information. The models of audio interface devices of the multiplex carriers include

ISWT3000, NSD550, and DIP5000.

Recently built 500kV power plants or substations in Pakistan employ computer-based

500kV line protection, bus protection, 500kV circuit breaker protection and fault

recorders.

2.2 Principles for Configuration of AC System Protection

2.2.1 Protection of 500 kV Lines

(1) R11 Distance Protection relay Panel – (Set-I).

The main equipment for relay panels are elucidated below:

Sr. No. Description. Quantity.

1. Distance Relay Set-I One

2. Auto-reclosure with

Built-in synchro-check

relay

One

3. Over voltage relay One

4. Multiple contact high

speed, high burden, self

reset tripping relay

Having (8NO + 2NC)

contacts with hand reset

flag.

Three Nos.

5. D.C. Supervision Relay One No.

6. Test block. Min five Nos. or as per

approved scheme.

(2) R12 Distance Protection relay panel – (Set-II).



1. Distance Relay Set-II a One No.

2. Auto-reclosure with

Built-in synchro-check

relay

One No.

3. Three phase and one

earth fault element

non-directional over

current and earth fault

relay

One No.



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speed, high burden, self

reset tripping relays

having (8NO + 2NC)

contacts with hand reset

flag as specified i

Four Nos.

5. D.C. Supervision Relay One No.

6. Test block. Min 6 Nos. or as approved

scheme.

2.2.2 Protection of 500kV Circuit Breaker

(1) R15 Breaker failure protection relay panel for three breakers.



1. Breaker failure relay with

two stage timers

Three Nos. for 500 KV

circuit breaker.


speed, high burden, hand

and electrical reset

lockout tripping relay

Three Nos. OR Six Nos. for

each bus bar breaker failure

protection.



and electrical lockout

tripping relay

Two OR Four Nos. for mid

breaker B.F.

4. Electrical Reset Relay One No.

5. DC supervision relay One No.

6. Test block. Quantity as required to suit the

scheme.

(2) R16 Trip circuit supervision relay panel for three breakers.



1. Trip circuit supervision

relay for each pole

18 Nos. for 500 KV circuit

breakers.

2. Auxiliary relays Quantity as required to suit the

scheme.

3. DC supervision relay Two Nos.

2.2.3 R17 Bus Protection

The main equipment for relay panels are elucidated below: High impedance bus differential OR

Optional low impedance bus differential relay.


1. Bus bar protection for 500

KV bus 1

.

One

2. Bus bar protection for 500

KV bus 2

.

One

2.2.4 Shunt reactor protection panel R20



Volume Ⅱ-1 -4


1. Percentage biased

differential relay as

specified

One No.

2. Restricted Earth fault relay One No.

3. Over current and earth

fault relay

One No.

4. Trip circuit supervision

relay for each pole of

circuit breaker.

Six Nos.

5. Breaker failure relay One No.

6. Multiple contact, high


and electrical reset lockout

tripping relay having

(8NO+2NC) contacts

Quantity required as suit

the scheme.

7. Test block. Three Nos.

2.2.5 Fault Recorder

To analyze the accidents of power system and the action of relay protection devices,

fault recorders should be provided in the relay rooms to record the line current and

voltage, action of protection devices, and operation of protection channels. These

information can be uploaded to the dispatch center via the protection and fault

information slave station.

(1) The fault recorders should be computer-based and in conformance to the

applicable industrial standards.

(2) The fault recorders in the substations should be of the same model and be

networked together, and connected to the relay protection and fault recording

information management slave station for uploading the information to the

dispatch department for accident analysis and resolution.

(3) The fault recorders should be equipped with multiple GPS synchronization

interfaces for better analysis on the occurrence time sequence of faults.

(4) The fault recorders should have optimum analysis and local networking

functions.

(5) The fault recorders should have optimum fault distance measurement function.

2.3 Configuration Scheme of Relay Protection

Refer to:

Fig.Volume II-1-1: Single Line Diagram of 500kV Protection System of Matiari;

Fig.Volume II-1-2: Single Line Diagram of 500kV Protection System of Lahore.



Volume Ⅱ-1 -5

2.4 Basic Requirements for Protection Devices

2.4.1 General Requirements

(1) The size of AC system protection panel (including 500kV line protection,

500kV Bus bar protection, 500kV Breaker Failure protection, 500kV shunt

reactor protection) shall be 800 x 800 x 2200 mm.

The size of Other protection & control panel (including 500/35kV step-down

transformers protection, 35kV reactor protection , 35kV bus bar

protection, 35 kV transformers protection, 10kV transformers protection,

fault recorder, etc.) shall be 800 x 600 x 2200 mm.

(2) The protection devices shall have the characteristics matching with those of the

connected current transformers and be adaptive to the CVT or bus PT on the

line side.

(3) The logic circuit of each protection device should be powered by independent

DC-DC converter, and when the DC voltage is lost, the protection device should

not act inadvertently and should provide output contact start event records and

alarm signals.

(4) The protection device should not act inadvertently even if any component is

damaged. In addition, automatic detection function should be provided to give

alarm signals when the circuit is abnormal.

2.4.2 Technical Requirements for Fault Recorder

(1) Digital fault recorders which can monitor the operation of power system

continuously should be used. The fault recorders should start recording when any

starting component acts. When the fault is eliminated or the system oscillation

stops, the starting component should return and stop recording after the pre-set

time. The recording function should works even during the single-phase reclosing

process.

(2) When a fault or oscillation occurs to the power system, the starting components

of the fault recorders should be able to start. Manual starting buttons should be

provided separately.

(3) The fault recorders should record and save the electrical waveforms from 150ms

before the fault till the fault disappearance, and clearly record the waveforms of

at least five harmonics.

(4) The fault recorders should record the current, voltage, remote protection signals,

active power, reactive power, system frequency, and protection action signals.

The sampling frequency for analog signals should not be less than 2000Hz.



Volume Ⅱ-1 -6

(5) Each fault recorder should be provided with one display and its own printer to

print the recorded information when needed.

(6) The resolution of the event records should be less than 1.0ms.

(7) The fault recorders should be provided with synchronization device to receive the

GPS synchronization clock pulses. Such device should be able to indicate the

second, minute, hour, date, month, and year.



Volume Ⅱ-1 -7

3. System Dispatch Automation

3.1 Dispatch Administrative Relations

In accordance with the dispatch administrative principles of Pakistan, the operating

conditions of Matiari and Lahore Converter Stations and 500 kV lines will be subject

to the monitoring of the National Power Control Center (NPCC), and the telecontrol

information should be delivered to the NPCC.

3.2 SCADA system Information

The SCADA information shall satisfy the following principles:

(1) Complete telecontrol information should be collected in a timely manner to fully

reflect the operating conditions of the power grid.

(2) Information collection shall meet the needs of all levels of dispatch centers for

hierarchical management and independent accounting.

(3) Information collection shall meet the requirements of power grid security

monitoring and advanced application functions.

(4) The SCADA information shall be directly collected and transmitted.

3.2.1 Telemetering

● Current, voltage, active power and reactive power of 500 kV AC lines;

● Voltage and frequency of 500 kV AC busbar;

● Direct current and harmonic current per pole;

● Electrode line current, harmonic current and ampere-hours;

● DC busbar voltage and harmonic voltage per pole;

● Neutral bus voltage;

● Current active power, maximum and minimum transmitted power and power

ramp rate per pole;

● Firing angle α of the rectifier station/extinction angle γ of the inverter station;

● Reactive power and busbar voltage of AC filter bank;

● Reactive power of AC filter subbank;

● Current, voltage, active power and reactive power on the AC side of converter

transformer;



Volume Ⅱ-1 -8

● Current and voltage on the valve side of converter transformer;

● Tap changer positions of converter transformer;

● Oil temperature and winding temperature of converter transformer.

3.2.2 Telesignaling

● Position signal (two-position signal) of circuit breaker in AC switchyard;

● Position signal (two-position signal) of disconnector in AC switchyard;

● 500 kV AC busbar protection operation signal;

● 500 kV AC line protection operation signal;

● 500 kV AC circuit breaker failure protection operation signal and reclosing

operation signal;

● DC operation mode signal (bipolar/monopolar/MR/GR, power direction, reduced

voltage operation, additional control, etc.);

● DC control mode signal (power control/current control/joint control and

independent control, etc.);

● Position signal of circuit breaker in DC switchyard;

● Position signal of disconnector and earthing knife blade in DC switchyard;

● Converter transformer protection operation signal;

● Converter valve main protection operation signal;

● Pole main protection operation signal;

● Bipole main protection operation signal;

● Main alarm signals of converter valve.

3.2.3 Teleregulation/Telecontrol

● 500 kV AC circuit breaker opening/closing control;

● Switching of reactive power compensation device;

● Master/slave control station selection command;

● Lead pole selection command;

● DC circuit breaker closing/opening command;

● (Bipole) pole start/stop command;



Volume Ⅱ-1 -9

● DC operation mode selection command;

● DC control mode selection command;

● (Bipole) pole current/power step up, step down and stop command;

● Automatic power curve power and time setting command.

3.3 SCADA System Scheme

The SCADA system is configured in combination with the scheme for network

control system. The telecontrol system (RTU) and the network control system share

the data acquisition unit. Redundant telecontrol workstations are connected to the

SCADA system. The data is directly transmitted to the SCADA workstation without

being processed by the host station of network control system. The SCADA

workstation is operating independent of the background network control system

without interference.

The SCADA information of converter station should be transmitted to the NPCC

through RTU.

3.4 Energy Metering System

3.4.1 Provision of Metering Points

The metering points of Matiari and Lahore Converter Stations are tentatively provided

at the following locations:

● Outgoing line side of 500 kV AC line

● AC side of converter transformer

● Incoming line side of external auxiliary power supply

3.4.2 Configuration of Energy Metering System

Two (active and standby) bi-directional 0.2s multi-rate energy meters are installed at

each metering point. The active energy metering system is supplied by the purchaser;

And standby energy metering system is supplied by the company. Details are as

follows:



Volume Ⅱ-1 -10

Table 3.4-1: Configuration of energy meters at metering points

Metering Point Quantity of Energy Meters

Accuracy Matiari Lahore

Each circuit of 500 kV line 8×2 6×2 0.2s for active, 1.0s for reactive

AC side of converter transformer 2×2 2×2 0.2s for active, 1.0s for reactive

External auxiliary power supply 2×2 1×2 0.2s for active, 1.0s for reactive

Matiari and Lahore Converter Stations are provided with two sets of energy remote

terminals, to which energy meters are connected through serial ports. The energy

remote terminal shall reliably and accurately collect and store the metering data from

all energy meters and transmit to the network control system.

Documents

System Protection