A PRACTICAL TRAINING REPORT ON

“ 400 KV GRID SUB STATION ,HEERAPURA”

Submitted in partial fulfillment of the requirement for the award of the degree of

BACHELOR OF TECHNOLOGY IN ELECTRICAL ENGINEERING

SESSION:2015-16

Submitted By:

MOHIT KOTHARI

12ESKEE726

Submitted To: Department of Electrical Engineering

Swami Keshvanand Institute Of Technology,Management

& Gramothan, Jaipur(Raj.)

i

ii

SWAMI KESHVANAND INSTITUTE OF TECHNOLOGY MANAGEMENT AND GRAMOTHAN,JAIPUR 2014-2015

CANDIDATE’S DECLARATION

I hereby certify that the work is being presented in the practical training report on “400KV GSS HEERAPURA” in partial fulfillment of the requirements for the award of the degree of B.tech and submitted in the Department of Electrical Engineering of SWAMI KESHVANAND INSTITUTE OF TECHNOLOGY, MANAGEMENT AND GRAMOTHAN,JAIPUR is an authentic record of my own work carried out during a period from “18May 2015 to 18July 2015”.

The matter presented in this report embodies the result of my own work and studies carried out by me.

MOHIT KOTHARI

This is to certify that the above statement made by the candidate is correct to the best of my/our knowledge.

Date: 28 NOVEMBER 2015 Mr. Shobhit Ahuja

(Seminar Coordinator)

iii

ACKNOWLEDGMENT

I am grateful to my training guide in R.R.V.P.N.L. whose encouragement and cooperation

has been a source of great inspiration. I express my sincere thanks to Mrs. Nidhi Bhatnagar

(Executive Engineer R.R.V.P.N.L. 400KV GSS, Heerapura) for her painstaking efforts and

enthusiastic cooperation to make my training possible. I also cordially thank the Mr. A.P.

Vishnu for his valuable support and guidance during my practical training at 400kV GSS,

Heerapura, Jaipur. I am also thankful to our instructors and other technical and non-technical

staff, for helping in understanding the various aspects and constructional details of work and site

in 400kV G.S.S. Heerapura, Jaipur.     

I would like to express my deep gratitude to Training & Placement cell SKIT, Jaipur for

granting me the opportunity for vocational training and providing all the necessary resources for

this purpose.

I would like to thank God ,my colleagues, the entire faculty members and the training incharge

of SKIT, Jaipur for their effort of constant co-operation kind support and valuable guidance

which have been a significant factor in the accomplishment of my summer training.

MOHIT KOTHARI

B.tech VII Semester

12ESKEE726

iv

PREFACE

As per the requirement of B. Tech. Course, 400 KV GSS HEERAPURA, JAIPUR (RAJ.)

has been kind enough to permit me to complete my Practical Training of 60 days.

This report prepared during the practical training which is student’s first and greatest treasure

as it is full of experience, observation and knowledge.

The summer training was very interesting and gainful as it is close to real what has been

studied in all the years through was seen implemented in a modified and practical form.

GSS is means of connection between generating station and consumer by providing safety

and reliability of system in case of fault. 

400 KV Grid Sub Stations, a high voltage substation receiving electricity with minimum

transmission losses and forwarding the step down voltage levels for further distribution to

our house holds or GSS. A training session out there will help you understand the various

devices used in transmission, possible loses, and practical approach of various aspects of

transmission and distribution Arrangement of different feeder level and switch yards

information, bus bar arrangement are included.     

v

CONTENTS

Page No.

CERTIFICATE ii

CANDIDATE’S DECLARATION iii

ACKNOWLEDGEMENT iv

PREFACE v

CONTENTS vi

LIST OF FIGURES

LIST OF TABLES

Chapter 1 INTRODUCTION

1.1 Overview

1.2 Introduction of R.S.E.B.

1.3 Substations

1.3.1 Functions

1.3.2 Classification

1.4 Understanding Key Elements of the T&D Space

1.5 400KV GSS Heerapura

1.5.1 Incoming Feeders

1.5.2 Outgoing Feeders

1.6 Single Line Diagram

Chapter 2 TRANSFORMER

2.1 Introduction 2.1.1 Types of Transformer

vi

2.2 Parts and Fittings of Power Transformer

Chapter 5 CONTROL ROOM

5.1 Introduction5.2 CRT Display 5.2.1 Indicating System 5.2.2 Relay Section 5.2.3 Master Relay 5.2.4 Meter Section 5.2.5 Announcing Section 5.2.6 Event Logger 5.2.7 Scanning and Indication5.3 Measuring Instruments  5.3.1 Synchronizing Panel 5.3.2 Syncronoscope

vii

Chapter 6 POWER LINE CARRIER COMMUNICATION

6.1 Introduction6.2 PLCC Equipment 6.2.1 Wave trap 6.2.2 Coupling Capacitor 6.2.3 Line Matching Filter & Protective Equipments 6.2.4 Cables 6.2.5 Transmitter 6.2.6 Receiver 6.2.7 Transmission System6.3 Merits and Demerits of PLCC

LIST OF FIGURES

Fig NO. Figure Description Pg No.

df

f d

viii

ix

LIST OF TABLES

Table NO. Table Description Pg No.

x

Chapter 3

BUS BARS

4.1 INTRODUCTION

Bus bars are important components of substation. When numbers of generators or feeders

operating at the same voltage have to be directly connected electrically, bus bar is used as the

common electrical component. Bus bars are made up of copper rods operate at constant voltage.

The outdoor bus bars are of two types viz the rigid type or strain type.

In the rigid type of bus bars, pipes are used. The pipes are also used for making connections

among different connections. The pedestal insulators support the bus bars and the connections.

The equipments and the bus bars are spread out and it requires large space. The clearances

remains constant as the bus bars are rigid.

It has following advantages-

1. The maintenance is easy as bus bars and connections are not very high from the ground.

2. As pipe diameter is large corona loss is less.

3. Reliability is more than strain type.

Following are the limitations-

1. Larger area is required.

2. It requires comparatively higher cost.

In stain type, bus bars are an overhead system of wires between two supporting structures and

supported by strain type insulators. As per the size of conductor, the stringing tension can be

limited (500-900kg).

The advantage of this type is its economy and it is recommended presently due to general

shortage of aluminum pipes. The material used in case of rigid type bus bars is aluminum pipes.

The general size of pipes commonly used for voltages are as given below-

33KV 40mm

66KV 65mm

132KV 80mm

220KV 80mm

400KV 10mm

xi

Due to rapid oxidation of aluminum, proper care must be taken while doing connections. In order

to avoid strain of supporting insulators due to thermal expansion and contraction of pipe, joints

should be avoided.

In case of strain type arrangement material used is ASCR (Aluminum Conductors with Steel

Reinforcement) and all aluminum conductors. For high rating of bus bars Bundled conductors

are used.

66KV 37/2.79mm ACSR

132KV 37/2.79mm ACSR

220KV 613/3.99mm ACSR

400KV 62/4.27mm ACSR duplex

Fig.3.1 Pipe Bus Bar

xii

4.2 BUS BAR SCHEMES

There are many different electrical bus system schemes available but selection of a particular

scheme depends upon the system voltage, position of substation in electrical power system,

flexibility needed in system and cost to be expensed.

The Main Criteria’s to be considered during Selection of one Particular Bus – Bar Arrangement

Scheme among Others

(i) Simplicity of system. (ii) Easy maintenance of different equipments. (iii) Minimizing

outage during maintenance. (iv) Future provision of extension with growth of demand.

(v) Optimizing the selection of bus bar arrangement scheme so that it gives maximum return

from the system.

4.2.1 Single Bus System

Single Bus System is simplest and cheapest one. In this scheme all the feeders and transformer

bay are connected to only one single bus as show.

 a. Merits

1. Low Cost

2. Simple to Operate

3. Simple Protection

b. Demerits

1. Fault of bus or any circuit breaker results in shut down of entire substation.

2. Difficult to do any maintenance.

3. Bus cannot be extended without completely DE energizing substations.

c. Remarks

1. Used for distribution substations up to 33kV.

2. Not used for large substations.

3. Sectionalizing increases flexibility.

xiii

4.2.2 Double Bus System

1. In double bus bar system two identical bus bars are used in such a way that any outgoing or

incoming feeder can be taken from any of the bus.

2. Actually every feeder is connected to both of the buses in parallel through individual isolator.

By closing any of the isolators one can put the feeder to associated bus. Both of the buses are

energized and total feeders are divided into two groups, one group is fed from one bus and other

xiv

from other bus. But any feeder at any time can be transferred from one bus to other. There is one

bus coupler breaker which should be kept close during bus transfer operation. For transfer

operation, one should first close the bus coupler circuit breaker then close the isolator associated

with the bus to where the feeder would be transferred and then open the isolator associated with

the bus from where feeder is transferred. Lastly after this transfer operation he or she should

open the bus coupler breaker.

a. Merits

1. High flexibility

2. Half of the feeders connected to each bus

b. Demerits

1. Extra bus-coupler circuit breaker necessary.

2. Bus protection scheme may cause loss of substation when it operates.

3. High exposure to bus fault.

4. Line breaker failure takes all circuits connected to the bus out of service.

5. Bus couplers failure takes entire substation out of service.      

c. Remarks

Most widely used for 66kV, 132kv, 220kV and important 11kv, 6.6kV, 3.3kV

4.2.3 Main and Transfer Bus System

The main conception of Main and Transfer Bus System is, here every feeder line is directly

connected through an isolator to a second bus called transfer bus. The said isolator in between

transfer bus and feeder line is generally called bypass isolator. The main bus is as usual

connected to each feeder through a bay consists of circuit breaker and associated isolators at both

side of the breaker. There is one bus coupler bay which couples transfer bus and main bus

through a circuit breaker and associated isolators at both sides of the breaker. If necessary the

transfer bus can be energized by main bus power by closing the transfer bus coupler isolators and

then breaker. Then the power in transfer bus can directly be fed to the feeder line by closing the

bypass isolator. If the main circuit breaker associated with feeder is switched off or isolated from

system, the feeder can still be fed in this way by transferring it to transfer bus.

xv

a. Merits

1. Low initial & ultimate cost

2. Any breaker can be taken out of service for maintenance.

3. Potential devices may be used on the main bus.

b. Demerits

1. Requires one extra breaker coupler.

2. Switching is somewhat complex when maintaining a breaker.

3. Fault of bus or any circuit breaker results in shutdown of entire substation.

xvi

4.2.4 Double Breaker Bus System

In double breaker bus bar system two identical bus bars are used in such a way that any outgoing

or incoming feeder can be taken from any of the bus similar to double bus bar system. Only

difference is that here every feeder is connected to both of the buses in parallel through

individual breaker instead only isolator as shown in the figure. By closing any of the breakers

and its associated isolators, one can put the feeder to respective bus. Both of the buses are

energized and total feeders are divided into two groups, one group is fed from one bus and other

from other bus similar to previous case. But any feeder at any time can be transferred from one

bus to other. There is no need of bus coupler as because the operation is done by breakers instead

of isolator. For transfer operation, one should first close the isolators and then the breaker

associated with the bus to where the feeder would be transferred and then he or she opens the

breaker and then isolators associated with the bus from where feeder is transferred.

a. Merits

1. Each has two associated breakers

2. Has flexibility in permitting feeder circuits to be connected to any bus

3. Any breaker can be taken out of service for maintenance.

4. High reliability

b. Demerits

1. Most expensive

2. Would lose half of the circuits for breaker fault if circuits are not connected to both the buses.

xvii

4.2.5 One and A Half Breaker Bus System

This is an improvement on the double breaker scheme to effect saving in the number of circuit

breakers. For every two circuits only one spare breaker is provided. The protection is however

complicated since it must associate the central breaker with the feeder whose own breaker is

taken out for maintenance. For the reasons given under double breaker scheme and because of

the prohibitory costs of equipment even this scheme is not much popular. As shown in the figure

that it is a simple design, two feeders are fed from two different buses through their associated

breakers and these two feeders are coupled by a third breaker which is called tie breaker.

Normally all the three breakers are closed and power is fed to both the circuits from two buses

which are operated in parallel. The tie breaker acts as coupler for the two feeder circuits.

During failure of any feeder breaker, the power is fed through the breaker of the second feeder

and tie breaker, therefore each feeder breaker has to be rated to feed both the feeders, coupled by

tie breaker.

xviii

a. Merits

1. Flexible operation for breaker maintenance.

2. Any breaker can be removed from maintenance without interruption of load.

3. Requires 1 1/2 breaker per feeder.

4. Each circuit fed by two breakers.

5. All switching by breaker.

6. Selective tripping.

b. Demerits

1. One and half breakers per circuit, hence higher cost

2. Any breaker can be removed from maintenance without interruption of load.

c. Remarks

1. Used for 400kV & 220kV substations.

xix