King Abdul Aziz University King Abdul Aziz University College of Engineering College of Engineering

Electrical and Computer DepartmentElectrical and Computer Department

EE 454EE 454SWITCHG.& PROT. OF PWR. SYSSWITCHG.& PROT. OF PWR. SYS . .

Lectures BookLectures Book

Dr. ABDULRAHMAN ALMASOUDDr. ABDULRAHMAN ALMASOUD

Function Of Industrial Switchgear

Foreword

Purpose And Types

Switchgear & ProtectionSwitchgear & ProtectionLecture 2

System and substation layout:

System layoutSystem layout::

I- I- radial feeder feeder..

II- parallel feeder.

III- ring system.

Iv- combination of the past three kinds.

Substation layoutSubstation layoutSubstation layoutSubstation layout::

Substations usually different in size, construction, cost and complexity according to voltage, location and function.

The common feature they have is marshalling of all the associated circuits, through CB, switches on to bus bar as shown Fig (1-2-2A).

(From Protection Relaying by Blackburn Page 338)1-Single bus –single breaker Fig (10.1)2-Double bus – with bus tie single breaker Fig (10.2)3-Main & transfer bus – single breaker Fig (10.3)4-Double bus – single breaker Fig (10.4)5-Double bus – Double breaker Fig (10.5)6-Ring bus Fig (10.6)7-Breaker and a half bus Fig (10.7)8-Bus and transformer single breaker Fig (10.8)

Function of Substation

Introduction:

Functions of Substation

Voltage Transformer – function 1

Circuit Switching – function 2

Voltage Regulation – function 3

VAR Control – function 4

System Protection – function 5

Design Considerations

Safety

Simplicity

Reliability

Maintenance

Flexibility

Radial Systems

Introduction

Simple Radial Systems

Expanded Radial Systems

Single-Ended Unit Substations

Radial SystemsSimple And Expanded Radial Systems

Radial SystemsSingle-Ended Unit Substations

Loop Systems

Primary Loop Systems

Secondary Loop Systems

Loop SystemsPrimary Loop Systems

Selective Systems-:

Primary selective system

Secondary Selective System-: