REPORT- RADIAL FEEDER PROTECTION PANEL DEVELOPMENT

“Radial feeder protection panel development
(INDUSTRIAL DEFINED PROJECT)”
Himanshu
Mr. Nayan
Prof. Manan M Desai
Dr. Subhash Technical Campus
A PROJECT REPORT SUBMITTED TO
GUJARAT
IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR
THE DEGREE OF BACHLOR OF ENGINEERING
DEPARTMENTOF
DR. SUBHASH TECHNICAL CAMPUS
KHAMDHROL ROAD, JUNAGADH
BY
ChiragKarsanbhaiDevaliya (120830109044)
HardikDilipkumarSolanki (120830109050)
Himanshu HasmukhbhaiPaghdal (120830109054)
Chirag PravinbhaiDholariya(120830109055)
UNDER THE GUIDANCE OF
NayanChhayaProprietor of Niyati Engineers&
Prof. Manan M DesaiHead of Department – Electrical,
Dr. Subhash Technical Campus – Junagadh
A PROJECT REPORT SUBMITTED TO
GUJARAT TECHNOLOGICAL UNIVERSITY
IN
ELECTRICAL ENGINEERING
2015-2016
EPARTMENTOF ELECTRICAL ENGINEERING
DR. SUBHASH TECHNICAL CAMPUS
KHAMDHROL ROAD, JUNAGADH - 362001
Devaliya (120830109044)
120830109054)
Dholariya(120830109055)
&
Electrical,
NGINEERING
362001

1
CERTIFICATE
This is to certify that research work embodied in this thesis entitled “RADIAL FEEDER
PROTECTION PANEL DEVELOPMENT” was carried out by Mr. CHIRAG DEVALIYA
- Enrollment No.120830109044, Mr. HARDIK SOLANKI - Enrollment No. 120830109050,
Mr. HIMANSHU PAGHDAL - Enrollment No.120830109054 and Mr. CHIRAG
DHOLARIYA - Enrollment No.120830109055 at Dr. Subhash Technical Campus, Junagadh
for partial fulfillment of B.E. in Electrical degree to be awarded by Gujarat Technological
University. This Project work has been carried out under our supervision and is to satisfaction of
the department. The student’s work has been accepted for publication.
Date:
Place:
Prof. Manan M. Desai Prof. Manan M. Desai
Supervisor HOD
Electrical department
Prof. D.D. Patel
Principal, DSTC - Junagadh

2
ABSTRACT
Power distribution systems are the portion of electrical systems that connects consumers
to the source of bulk power. Distribution system consists of several substations which includes
one or more feeders. Radial feeder system consists of having only one path for power to flow
from the source to each consumer.
The protective systems of radial feeder are essential for the same. In this project we are
develop various protective schemes to avoid malfunctioning of electromechanical relay. Through
this project we are preparing operating panel of radial feeder protection as real substation
environment.
Through this practical set-up, the students, in addition to getting familiar with the
fundamentals of protection, learned how different protection schemes are wired and how they
operate in a real power system.

3
ACKNOWLEDGMENT
“Whenever a man achieves anything he mainly achieves by the blessings of his elder and his
own endurance and hard work.”
We appreciate our colleagues and friends who have helped, inspired and given moral support and
encouragement, in various ways, in completing this task. We are pleased to acknowledge the
helpful comments and suggestion provided by our friends and colleagues.
We are special thanks to Prof. Manan Desai to provide us valuable guidance throughput the
project preparation and presentation.
We are greatly thankful to all faculty members of Electrical department.
Chirag KarsanbhaiDevaliya
Hardik DilipkumarSolanki
Himanshu HasmukhbhaiPaghdal
Chirag Pravinbhai Dholariya

4
INDEX
Chapter 1: Introduction
1.1 What is feeder? ………………………………………...……………………………......06
1.2 Types of Distribution System ...……………………...….………….…………………...06
1.2.1 Radial Electrical power system ….………….…...……………………………....07
1.2.2 Ring main Electrical power system.……………………….……………….……08
1.3 Radial feeder protection ...……………………………………………………………….10
1.3.1 Unite Scheme……………………………………...…………………………......11
1.3.2 Non Unit Scheme………………………………………………………………...11
1.3.3 Feeder Earth Fault Protection……………………………………………………13
1.4 Component Details……………………...………………………………………….…….14
1.5 Main Component Details……………………………………....…...…………….……...15
1.5.1 IDMT Electromechanical Relay………………………………………………....15
1.5.1.1 Features………………………………………………………………………16
1.5.1.2 Applications………………………….………………………………………16
Chapter 2: Literature surveys
2.1 Topic 1…………………………………………………………………………………...17
2.2 Topic 2…………………………………………………………………………………...18
Chapter 3: Project Working
3.1 Timer and Control Diagram…………………………………………………………......20
3.2 Power Wiring Diagram…………………………………..………….………………...…21
3.3 Current Injection Measurement Circuit……….….…………..………..………………...22
3.4 Component Price Quotation………………………….…………….………………….…23
Chapter 4: Work done
4.1 Testing and table………………………………………………………………………...26
4.2 Curve………………………………………………………………………….…………27
Chapter 5: Design: Analysis, Design Methodology
5.1 The Business Model Canvas………………………………………….…………………28
5.2 Components Mounting in Panel………………………………………………………...33

5
Chapter 6: Conclusion and Future Scope
6.1 Conclusion………………………………….……………………………………………….35
6.2 Future Scope………………………………..………………….………………………..…...35
Chapter 7: Bibliography
INDEX of Figure and Tables
SR. NO. FIGURE NAME PAGE NO.
1. Distribution System 06
2. Radial Distribution System 07
3. Ring Main Electrical Power Distribution System 08
4. Radial Distribution System 12
5. Feeder Earth Fault Protection 13
6. Type CDG 11 Overcurrent and Earth fault Relay 15
7. Type CDG 11 Overcurrent and Earth fault Relay 20
8. Timer Control Diagram 20
9. Power Wiring Diagram 21
10. Current Injection And Measurement Circuit 22
11. Radial Feeder Protection Panel Setup 25
12. Testing And Table 26
13. Curve 27
14. The Business Model Canvas 28
15. Components Mounting In Panel 33

6
Chapter 1: Introduction
1.1 What is Feeder?
 The word FEEDER may be referred as the connecting link between the two circuits. The
feeder could be in the form of transmission line that is short, medium or long or this
could be a distribution circuit
 Power is transferred through feeders from source to load.
Figure:1
1.2 Types of Distribution System
 There is a mainly two types of Electrical Power Distribution Systems
1) Radial Electrical Power Distribution System
2) Ring Main Electrical Power Distribution System

7
1.2.1Radial Electrical Power Distribution System
 In early days of electrical power distribution system, different feeders were radially come
out from the substation and connected to the primary of distribution transformer directly.
Figure:2
 But radial electrical power distribution system (Fig.2) has one major drawback that in
case of any feeder failure, the associated consumers would not get any power as there
was no alternative path to feed the transformer. In case of transformer failure also, the
power supply is interrupted.
 In other word the consumer in the radial electrical distribution system would be in
darkness until the feeder or transformer was rectified.

8
1.2.2Ring Main Electrical Power Distribution System
 The drawback of radial electrical power distribution system can be overcome by
introducing a ring main electrical power distribution system. Here one ring network of
distributors is fed by more than one feeder. In this case if one feeder is under fault or
maintenance, the ring distributor is still energized by other feeders connected to it.
 In this way the supply to the consumers is not affected even when any feeder becomes
out of service. In addition to that the ring main system is also provided with different
section isolates at different suitable points. If any fault occurs on any section, of the ring,
this section can easily be isolated by opening the associated section isolators on both
sides of the faulty zone.
Figure.3

9
 In this way, supply to the consumers connected to the healthy zone of the ring, can easily
be maintained even when one section of the ring is under shutdown
 The number of feeders connected to the ring main electrical power distribution
system(Fig.3) depends upon the following factors.
1. Maximum demand of the system: If it is more, then more numbers of feeders feed the
ring.
2. Total length of the ring main distributors: It length is more, to compensate the voltage
drop in the line, more feeders to be connected to the ring system.
3. Required voltage regulation : The number of feeders connected to the ring also depends
upon the permissible allowable, voltage drop of the line.
 The sub distributors and service mains are taken off may be via distribution transformer
at different suitable points on the ring depending upon the location of the consumers.
 Sometimes, instead of connecting service main directly to the ring, sub distributors are
also used to feed a group of service mains where direct access of ring distributor is not
possible.

10
1.3Radial Feeder Protection
 Overhead lines or cables which are used to distribute the load to the customers they
interconnect the distribution substations. This is an electrical supply line, either overhead
or underground, which runs from the substation, through various paths, ending with the
transformers. It is a distribution circuit, usually less than 69,000 volts, which carries
power from the substation with the loads.
 The modern age has come to depend heavily upon continuous and reliable availability 0f
electricity and a high quality of electricity too. Computer and telecommunication
networks, railway networks, banking and continuous power industries are a few
applications that just cannot function without highly reliable power source. No power
system cannot be designed in such a way that they would never fail. So, protection is
required for proper working.
 Power distribution systems are that portion of electrical systems that connects customers
to the source of bulk power (such as distribution substation). Radial distribution systems
are characterized by having only one path for power to flow from the source to each
customer. A typical distribution system consists of several substations which each
includes one or more feeders. A three-phase primary feeder extends away from a
substation, and there are many lateral feeders (three-phase, two-phase or single-phase)
extending away from the primary feeder. There are loads, transformers, shunt capacitor
banks, and protective devices in a distribution feeder. There are a large number of
components in distribution systems and these components age over time. Further most
distribution systems are overhead systems, which are easily affected by weather, animals,
etc.

11
 These two reasons make faults in distribution systems inevitable. To reduce operating
cost and outage time, fast and accurate fault location is necessary. The need to analyze
protection schemes has resulted in the development of protection coordination programs.
 Protection schemes can be divided into two major groupings:
(i) Unit schemes
(ii) Non-unit scheme
1.3.1 Unit Scheme
 Unit type schemes protect a specific area of the system, i.e., a transformer, transmission
line, generator or bus bar.
 The most obvious example of unit protection schemes is based on Kerchief’s current law
– the sum of the currents entering an area of the system must be zero. Any deviation from
this must indicate an abnormal current path. In these schemes, the effects of any
disturbance or operating condition outside the area of interest are totally ignored and the
protection must be designed to be stable above the maximum possible fault current that
could flow through the protected area.
1.3.2 Non Unit Scheme
 The non-unit schemes, while also intended to protect specific areas, have no fixed
boundaries. As well as protecting their own designated areas, the protective zones can
overlap into other areas.
 While this can be very beneficial for back up purposes, there can be a tendency for too
great an area to be isolated if a fault is detected by different non unit schemes.

 The simplest of these schemes measures current and incorporates an inverse time
characteristic into the protection operation to allow protect
operate first.
of these schemes measures current and incorporates an inverse time
characteristic into the protection operation to allow protection nearer to the fault to
Figure:4
12
of these schemes measures current and incorporates an inverse time
ion nearer to the fault to

1.3.3 Feeder Earth Fault
Earth-fault protection is used to protect feeder against faults involving ground. Typically,
earth faults are single line to ground and double line to ground faults. For
setting and coordination, only single lines to ground faults are considered.
Earth Fault Protection
fault protection is used to protect feeder against faults involving ground. Typically,
earth faults are single line to ground and double line to ground faults. For
Figure: 5
13
fault protection is used to protect feeder against faults involving ground. Typically,
earth faults are single line to ground and double line to ground faults. For the purpose of

14
1.4Components Detail
1) IDMT Electromagnetic Relay
2) Ammeter
3) Connecter
4) Indicator
5) Toggle switch
6) Terminals
7) Wire
8) Panel Cabinet Box

15
1.5Main Components Detail
1.5.1 IDMT Electromechanical Relay
Figure: 6
 A non-directional heavily damped induction disc relay which has an adjustable inverse
time/current characteristic with a definite minimum time. The relay has a high torque
movement combined with low burden and low overshoot. The relay disc is so shaped that
as it rotates the driving torque increases and offsets the changing restraining torque of the
control spring. This feature combined with the high torque of the relay ensures good
contact pressure even at currents near pick-up. Damping of the disc movement is by a
removable high retentively permanent magnet.
 The unique method of winding the operating coil ensures that the time/current
characteristics are identical on each of the seven current taps. Selection of the required
current setting is by means of a plug setting bridge which has a single insulated plug. The

16
maximum current tap is automatically connected when the plug is withdrawn from the
bridge, allowing the setting to be changed under load without risk of open circuiting the
current transformers.
 The IDMT relay has an auxiliary unit which is powered by a secondary winding on the
electromagnet through a rectifier and as such a separate auxiliary supply is not required.
The disc unit operates and closes its contacts, the auxiliary element connected across the
secondary winding on the electromagnet operates, one normally open contact of the
auxiliary element reinforces the disc contact. Two other contacts of the auxiliary element
are brought out to the terminals of the relay.
 The relay operating time can be adjusted by movement of the disc backstop which is
controlled by rotating a knurled molded disc at the base of the graduated time multiplier
scale.
 Electromechanical protective relays operate by either magnetic attraction, or magnetic
induction. Unlike switching type electromechanical relays with fixed and usually ill-
defined operating voltage thresholds and operating times, protective relays have well-
established, selectable and adjustable time/current (or other operating parameter)
operating characteristics.
 Protection relays may use arrays of induction disks, shaded-pole magnets, operating and
restraint coils, solenoid-type operators, telephone-relay contacts, and phase-shifting
networks.
1.5.2Features
 Identical time/current characteristics on all taps.
 Self-powered, no necessity for separate auxiliary supply.
 High torque, ensuring consistent timing even under adverse conditions.
 Very low overshoot.
 Simple construction, easily accessible.
 Comprehensive range of high-set unit ratings.
 Dustproof draw out case and tropicalized finish.
1.5.3Applications
 Selective phase and earth fault protection, in time graded systems for AC machines,
transformers, feeders etc.

17
Chapter 2: Literature Surveys of Feeder Protection in Power
Distribution
Topic-1:Power Engineering Society Winter Meeting, 2002. IEEE
Abstract: -The Micro Grid concept assumes a cluster of loads and micro sources (<100 kW)
operating as a single controllable system that provides both power and heat to its local area. This
concept provides a new paradigm for defining the operation of distributed generation. To the
utility the Micro Grid can be thought of as a controlled cell of the power system. For example,
this cell could be controlled as a single dispatch able load, which can respond in seconds to meet
the needs of the transmission system. To the customer the Micro Grid can be designed to meet
their special needs; such as, enhance local reliability, reduce feeder losses, support local
voltages, provide increased efficiency through use waste heat, voltage sag correction or provide
uninterruptible power supply functions. This paper provides an overview of the Micro Grid
paradigm. This includes the basic architecture, control and protection and energy management.
Published in:
Power Engineering Society Winter Meeting, 2002. IEEE (Volume:1 )
Date of Conference:
2002
Page(s):
305 - 308 vol.1
Print ISBN:
0-7803-7322-7
INSPEC Accession Number:
7386317

18
Topic-2:Industry Applications Magazine, IEEE
Abstract: -The emphasis of this article is on distributed generators that are interconnected
to with utility distribution systems. These will generally be units smaller than 10 MW.
Larger units are generally connected directly to transmission facilities and will most
likely be commercial power producers. The units installed on distribution systems will
typically be no larger than 1 or 2 MW. These would be installed mostly by the utility
itself or by end users. This method of generation is commonly referred to as "distributed
generation" (DG)
Published in:
Industry Applications Magazine, IEEE (Volume:8 , Issue: 2 )
Page(s):
19 - 25
ISSN:
1077-2618
INSPEC Accession Number:
7199285
DOI:
10.1109/2943.985677
Date of Publication:
Mar/Apr 2002
Date of Current Version:
07 August 2002
Issue Date:
Mar/Apr 2002
Sponsored by :
IEEE Industry Applications Society
Publisher:
IEEE

19
Chapter 3:Project Working
 Once Project defined, our team has searched and found an external guide who will guide
us to act further. We have decided the size of panel and finalized a list of required
components according to it.
 Then after we have enquired for lowest quotation of components. We got a many
quotations from different sources. Then after we summarized for a lowest price vender
and we have ordered for a component.
 And we got the components and panel cabinet we have mounted the components. And
then we were going for wiring work for panel.
 Hear we use two over current relay (inverse) type cdg and one earth fault relay (inverse)
type cdg.
 After wiring will completed we will do testing of this panel.
 For reference please find the project developing Image is under below.
 A non-directional heavily damped induction disc relay which has an adjustable inverse
time/current characteristic with a definite minimum time. The relay has a high torque
movement combined with low burden and low overshoot. The relay disc is so shaped that
as it rotates the driving torque increases and offsets the changing restraining torque of the
control spring. This feature combined with the high torque of the relay ensures good
contact pressure even at currents near pick-up. Damping of the disc movement is by a
removable high retentively permanent magnet.
 The unique method of winding the operating coil ensures that the time/current
characteristics are identical on each of the seven current taps. Selection of the required
current setting is by means of a plug setting bridge which has a single insulated plug. The
maximum current tap is automatically connected when the plug is withdrawn from the
bridge, allowing the setting to be changed under load without risk of open circuiting the
current transformers.
 The figure shows two over current relay (inverse) type cdg and one earth fault relay
(inverse) type cdg.

20
Figure:7
3.1: Timer Control Diagram
Figure:8

21
3.2:Power Wiring Diagram
Figure:9

22
3.3:Current Injection and Measurement Circuit
Figure:10

23
3.4: Components Price Quotation

25
Chapter 4: Work Done
 Once Project defined, our team has searched and found an external guide who will
guide us to act further. We have decided the size of panel and finalized a list of
required components according to it.
 Then after we have enquired for lowest quotation of components. We got a many
quotations from different sources. Then after we summarized for a lowest price
vender and we have ordered for a component.
 After we got the components and panel cabinet we have mounted the components.
And then we were going for wiring work for panel.
 A wiring of Panel is almost completed.
 After wiring will completed testing of this panel.
 For reference the project developing Image is under below.
Figure:11

26
4.1: Testing table
Figure:12
NOLOADNOLOAD
Sr. P.S. TMS StartingCurrent EndingCurrent TrippingTime
R1 3.75 0.25 4.1 6 3.74
R2 2.5 0.25 2.8 3.8 4.1
R3 1 0.25 1.5 1.73 2.16
ON LOAD2KONLOAD2K
Sr. P.S. TMS StartingCurrent EndingCurrent TrippingTime
R1 3.75 0.25 4.8 6.4 1.15
R2 2.5 0.25 3.9 4.8 1.8
R3 1 0.25 1.1 1.4 4.2

28
Chapter 5: Analysis, Design Methodology and
Implementation Strategy
5.1THE BUSINESS MODEL CANVAS
Figure:14

29
Key Partners
 Finance:
The financers are the persons who invests in our project for
Developing the project in time and develop it.
 Engineers
Engineers are the persons who help us to design the panel and
Also help to making wiring of panel.
 Developers
Developers are the persons who develop the product and make
Modifications.
 Manufacturer
The Manufactures are the persons who help to find required
elements like relay, toggle switch, MCB etc.
Key activity
 Wiring
Here we make the wiring in this panel with the help of External
guide
.
 Design
the product we design the product according to the requirement
of costumer.
 Purchase
We purchase raw materials from the sellers of the raw materials
in mass.
 Selling
The manufactured product is sold by deciding perfect price.

30
Key Resources
 Electromechanical relay
They help us in selling the developed product in market in a
large region.
 Protective relay
Here we used electromechanically relay for protection against
overcurrent, under current and earth fault.
 Tools
Tools such as meters, solders etc. are used in the development
of project.
 Safety Equipment
Different safety Equipment used for protection of plant
andworkers.
Value Proportions
Here we used electromechanically relay for protection against
overcurrent, under current and earth fault.
 Verica
It is used for tasting purpose in our project.
 Reduction risk
During the testing we have less risk.
 Panel
It is used to settle all the equipment.

31
 Sharp fault detection
In this project all equipment considers and to detect fault.
Consumer relationships
 Feedback
Here we take feedback from the consumer as they are
Satisfiedwith our service or not.
 Maintenance
Here we time to time take care of the product which we have
erected.
Channels
 Sellers
They are the persons which helps us to reach to the market.
 Advertisements
We advertise our product through the printing and the digital
Media
.
 Web
We reach to each and every people through the social media
andwebsite.

32
Costumer segments
 Power plant
 Industry:
Our product is well suited for power plants.
Our product can be customized for home usage also.
 Sub stations
For transmission and distribution of power efficiently
Our product can be used.
Cost structure
 Economical
Cost of this project is economical.
 Other materials
Other materials such as wires, toggle switch, Protective relay etc.
 Flexible
The cost also considerable as flexible
Revenue stream
 Product Sell
 Cost cutting
Most of the money is made by selling of the product Done by
decreasing cost of company a side income like can

33
5.2Components mounting in Panel
Figure:15

34
 Here is the GA drawing of Panel.
 Connector is the starting and ending point of all wires.
 At the connector we have to inject the current from current injection kit.
 Over current relay 1 and Over current relay 2 indicators are over load or under load
indications.
 Power On Light is indicating the Power is ON.
 A-meter is showing the running actual current.
 Over current relay 1is Over load current relay, Earth fault relay is Earth fault tripping
relay and Over current relay 2 is Under load current relay.

35
Chapter 6: CONCLUSION and FUTURE SCOPE
6.1 CONCLUSION
This Setup shows protection by reconfiguration of a radial distribution network. An 11-
bus system was used for the purpose.
From this project, we can protect in distribution system by three mostly affecting faults
like over current, under current and earth fault with the use of the electromechanical
relay. Also with the use of PSM (Plug Setting Multiplier) and TSM (Time Setting
Multiplier), we can trip the relay by different types of timing situation and current.
By this set-up, we can study and to understand the basics of terminology. In addition of
this project, the electromechanical relay has limited used purpose. But implement or
used Numerical, Digital or Static relay, we occupied the fault very accurately and make
healthy the distribution system.
6.2FUTURE SCOPE
 When Distributed Generation is added to your circuit, a savings in initial cost of
protective relaying, engineering design, installation time plus conservation of
physical space for mounting equipment and periodic maintenance will be realized if
a multifunction protection package with both current and voltage inputs is already in
place for feeder protection. The additional protective elements available in these
packages will solve the protection issues addressed, regardless of the size or
number of DGs added to your circuit.
 With the increasing loads, voltages and short-circuit duty of distribution substation
feeders, distribution over current protection has become more important today
Power systems that have evolved in the 20th century consist of generation plants,

36
transmission facilities, distribution lines, and customer loads, all connected through
complex electrical networks.
 In the United States, electrical energy is generated and distributed by a combination
of private and public utilities that operate in interconnected grids, commonly called
power pools, for reliability and marketing. Elsewhere in the world, generation is tied
to load through national or privatized grids. Either way, power flows according to
electrical network theory.
 Interconnection improves the reliability of each pool member utility because loss of
generation is usually quickly made up from other utilities. However, interconnection
also increases the complexity of power networks. Power pool reliability is a function
of the reliability of the transmission in the individual members.
 Protection security and dependability is significant in determining the reliability of
electrical service for both individual utilities and the interconnected power system
pool.

37
Chapter 7: Bibliography
Books
 Power system protection and switchgear (2nd
edition)
By Badri ram and D. N. Vishwakarma
 Digital power system protects and switchgear (4th
edition)
By Bhuvnesh A. Oza
 Power system protection (2nd
edition)
By Ravindranath M. Chander
Others
 Managers of electrical Magazine
 Electrical4u Magazine
 Radial Distribution System Reconfiguration for Loss Minimization using Exhaustive
Search Techniques, By Utkarsh Singh
 BVM Panel Development Paper
Patents
 Automatic fault reporting system
Inventor: Charles E. Crowin
Patent no.4675975
Date: Sunday,13,1987
Inventor: R Sterns, F Sutter
Patent no:US3777093A
Research paper
 Radial Distribution Test Feeders, IEEE
Keywords: distribution system analysis, test systems, computer programs, transformer
models
 Development and analysis of radial feeder protection for capacitor
Switching transient, Dr.N. Loganathan
Keywords: Radial feeder protection, Capacitor switching, Series reactor, Transient
current

38
 Development of Power System Protection Laboratory Through Senior Design Projects,
By Bhavesh A. Oza and Sukumar M. Brahma, Member IEEE
Websites
 www.ieee.com
 www. electrical-engineering-portal.com
 www.siemens.com
 www.electricals4u.com
 new.abb.com
 www.authorstream.com
 www.engpaper.com
 www.littelfuse.com

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