VENKTESHWAR INSTITUTE OF TECHNOLOGY, INDORE BE- VI Semester, BRANCH: Electrical & Electronics Engg. Subject: Switchgear & Protection(EX-603) Faculty: Arvind Yadav Mobile No. of Faculty: +91-9893666587

e-Mail ID of Faculty Member: [email protected]

LESSON PLAN (Session:Jan-June’2011) Introduction:

Power systems are complex networks of generators and loads interconnected via transmission lines and various types of equipment and apparatus (transformers, switchgear, etc). An overview of modern power systems meeting present and future challenges involves understanding the fast changing structure of this system, the behavior of its components under steady state, dynamic and transient conditions, in order to be able to evaluate the response of this complex system to variation of loads, and to determine how this system can be controlled to supply the loads reliably while it is economical and safe to the environment.

Objective:

The course aims to provide the student with essential knowledge in high-voltage power system components and equipment such as their functions, physical design, factors affecting their operation, and diagnostic techniques to monitor their condition.

Course Contents:

Fault Analysis ,Proactive Relays ,Circuit Breakers ,System Protection ,Protection of Transformers,Surge Protection & insulation co-ordination

Application of the course:

Importance of the course:

The course will provide students with essential knowledge in power systems required for its analysis. Topics covered comprise: review of the basic concepts used in power system analysis: phasors, complex power, three phase systems and per-unit; introduction of equivalent circuit models for power system components including transformers, generators, transmission lines and loads; power system fault calculations including: symmetrical components, symmetrical faults, and unsymmetrical faults; surge propagation during transients in power system; power system stability by introduction of swing equation, and a multi-machine system; power system protection principles; power system control and economic dispatch. In this course we will discuss Protection of Electrical equipment from Dangerous Over Voltages or Short Circuit Faults using Protection systems ( such as Protective Relays; Circuit Breakers etc… ). At the end of this course the student is expected to be familiar with the Principles of Protective Systems and their application in real life. You are advised to read carefully through given material and attempt all quiz/questionaires in this course and dont forget to follow necessary safety code that will be outlined in this course. We hope you will enjoy this course in Electrical Engineering.

Special instructions for the students:

The course consists of the following elements: lectures, laboratory work, home work, and tutorials: Lectures: Students are expected to attend the lectures and prepare themselves for them. The lectures provide the students with a focus on the core material in the course. Generic features and functions of various types of major equipment and apparatus required in a typical power system network are explained. This is further illustrated with practical examples from Australian power utility installations. Mathematical tools and computer-aided analysis are then used to convey a qualitative understanding of critical issues affecting the operation of power system equipment. This in turn leads students to an appreciation of the equipment ratings, choice of particular insulation materials and designs. The basic principles covering the high-voltage testing and condition monitoring of equipment are presented and then illustrated by examining a wide array of diagnostic devices that are currently being used in the power industry. Laboratory work: The laboratory work provides the student with hands-on experience and exposure to practical high- voltage testing, measurement and reporting.The experiments will contain material that may not be covered in lectures until after the experiment is done. This requires that the laboratory sheets must be read thoroughly before the laboratory session. Students must come prepared for the laboratory sessions; the laboratory sessions are short, so this is only possible way to complete the given tasks. Tutorials: The tutorial sessions provide personal assistance to students in solving problems. A total of 5 problem sets will be presented throughout the semester and some of these will be worked through during the tutorials. The tutorials take the student through all critical course topics and aim to exercise the students’ analytical and critical thinking skills. Students are strongly encouraged to complete all the tutorial problems as these help to develop in-depth quantitative understanding of the course materials. During tutorials, students will also be invited to raise any concepts or topics covered in lectures with which they are experiencing difficulty and required another explanation. Tutorials are also opportunities for interactive discussion on any questions, issues or topics relevant to the course. Home work: The class lectures can only cover the course material to a certain depth; students must down-load the lecture notes (from the course web site) and reflect on its content as preparation for the lectures to fully appreciate the course material. Further research and reading from the recommended list of text/reference books are also required. The ability to read the literature, identify relevant parts and extract critical information with the aid of the lectures is regarded as an essential component of this course. Also, a significant component of home work is preparation for laboratory, tutorials, and writing laboratory reports.

Period No.

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2

3

4 5 6

7 8 9

10 11 12 13 14 15 16 17

Date held

Objective

To know about the per unit calculations. To analyse the faults in power systems To draw the line diagram of power systems. To analyse the faults in power systems with the help of symmetrical components.

Topic/Sub topic to be covered Unit-I Fault Analysis per unit, representation and its advantages

types of faults can be recognised.

Single line and equivalent impendence diagram representation of power system components

single line diagram can be drawn for complex power system.

Symmetrical components and its application to power systems fault analysis, fault analysis, Sequence networks and their interconnection for different types of faults Sequence networks and their interconnection for different types of faults

To calculate the short-circuit capacity of reactors

Effect of fault impedance Current limiting reactors, its location and application, Short circuit calculation. Unit-II Proactive Relays Requirement of relays,

To know about the components & working priciple of relays

p.u. calculations can be done for complex electrical parameters.

faults in power systems (Symmetrical & Unsymmetrical),

To draw the sequence network for various interconnected systems

To study about the requirement of relays for the power system protection To study the different characteristics of relays.

Skills to be developed

Primary & backup protection, Desirable qualities of relays, Concept of Pickup, reset & drop-off, Drop off/ Pickup ratio, invers inverse time & definite time charterstics, Attracted armature, Balanced Beam Induction disc, Induction cup, Moving coil & moving Iron, Rectifier ,

Reference

Book No.1: page 9-11

Book No.1: page 332-333

Book No.1: page305-307 Book No.1: page299-303

with the help of symmetrical components fault analysis can be done.

sequence networks can be drawn and analysed for different types of faults

short-circuit capacity can be calculated for variuos current limiting reactors.

Knowledge of power system protection can be developed.

characteristics of relays can be understood

working priciple of the relays can be understood.

Book No.1: page 308-325 Book No.1: page 308-325 Book No.1: page 329-333

Book No.1: page 329-332 Book No.1: page 333-335 Book No.1: page 338-339 Book No.1: page 340-342

Book No.1: page 359 Book No.1: page 360 Book No.1: page 361-363 Book No.1: page 364-365 Book No.1: page 366-369 Book No.1: page 370-376 Book No.1: page 377-380 Book No.1: page 381-386

Remarks

18 19 20 21 22

23 24 25 26

To study the different types of relays To study about the performance of relays. To classify the various relays based on the operating charecteristics

To know about the basic priciple of working of cicuit breaker.

To study about the various types of cicuit-breakers & fuses

27 28 29

30 31 32 33 34 35 36

To discuss the effect of reactors in CB ratings and testing of CB

To discuss the faults and failure in the generators and it's protection scheme

To study the faults in Transformers and it's protection

Thermal, Bimetal directional relay, Frequency, DC, all or nothing relays Pilot & negative sequence, Over current, Over Voltage, Directional, Differential and Distance relays, R-X diagram, Impedance mho & reactance relay. Introduction of static analog & digital relays, Classification of static relays. Unit-III Circuit Breakers Elementary principle of arc quenching, recovery & re-striking voltage, arc quenching devices, description and operation of Bulk oil, Minimum oil, Air break, Air blast, SF6, Vacuum circuit breakers and DC circuit breakers, their comparative merits, LT Switch gear, HRC fuses, current limiting reactor & influence of reactors in CB ratings, Testing of circuit breaker Unit-IV System Protection Protection of Generators - Earth Fault, percentage, differential, Loss of excitation, Prime mover failure, Over current, Turn to turn fault Negative phase sequence, heating, Reverse power protection schemes Protection of Transformers Internal & external fault protection, Differential, Earth fault, Over Current, Over heating, Protection schemes,

different types of relays can be recognised.

performance of the relays cane understood.

Students will be able to classify the various relays.

Book No.1: page 387-388 Book No.1: page 389 Book No.1: page 390 Book No.1: page 408 Book No.1: page 428

Students will be able to understand the working principle of circuit-breaker.

Types of circuit-breakers and fuses can be understood.

Book No.1: page 479 Book No.1: page 481-484 Book No.1: page 492495,500 Book No.1: page 496-499 Book No.1: page 461-464

Ratings of CB can be decided.

Students will be able to analyse the faults in the generators and which types of protection scheme can be used.

Students can detects the faults in the transformers and be able to understand

Book No.1: page 502-504 Book No.1: page 505-509

Book No.1: page 392-400 Book No.1: page 392-400 Book No.1: page 392-400 Book No.1: page 392-400 Book No.1: page 401-407 Book No.1: page 401-407 Book No.1: page 401-407

scheme.

37 38

39

To discuss the phenomenon of lightning , it's effect and protection against it.

40

To study about the various surge protection schemes like lightning arrestors,reactance earthing & earthing transformers etc

41 42 43 44 45

To determine the insulation level of sub-station equipments and transmission line

46 47

Protection of transmission lines, Over current, Distance and carrier current protection schemes. Unit-V Surge Protection & insulation coordination Switching surges, Phenomena of Lightning, over voltage due to lightning, Protection against lightning, Lightning arrestors, selection of lightning arrestors, Surge absorbers and diverters, Rod gap, Horn gap expulsion type & valve type lightning arrestors, solid resistance and reactance earthing, Arc suppression coil, Earthing transformers, Earthwires, Earthing of appliances, insulation co-ordination, Definitions determination of line insulation, insulation level of substation equipment, co- ordination amongst items of substation equipment

the varios protection schemes.

Book No.1: page 401-407 Book No.1: page 401-407

Students will be able to understood the concept of surge phenomenon due to lightning and switching and it's protection schemes

Book No.1: page 289-292

Students can recognise the surge effect and can be able to decide which tytpes of protection systems like rod gap,horn gap,reactors,earthing transformers can be used.

Book No.1: page 259-264

Students can understood the concept of insulation coordination and insulation lvel of substation equipments.

Book No.1: page 293-295

Book No.1: page 265-268 Book No.1: page 284-288 Book No.1: page 284-288 Book No.1: page 514-531 Book No.1: page 514-531 Book No.1: page 514-531

List of text and Reference books Title

Sr. No. Book No. 1 Book No. 2 Book No. 3

Authors C.L.Wadhwa

Electrical Power systems Electrical Power systems Power systems

Signature of Faculty Member

Ashfaq Hussain J.B. Gupta

Publisher New Age international (P) Ltd CBS Publication