Switch Gear and Protection - [2170908]


Teaching Scheme

Tutorial Practical Total
4 0 2 6

Examination Scheme

Theory Examination Practical Examination Total
ESE (E) PA (M) ESE Viva (V) PA (I)
70 30 30 20 150

    ESE = End Semester Examination, PA = Progressive Assessment

Course Type   

Syllabus Content

Faults, Causes and Effects, Protective Zones, Primary and Backup Protection, Desirable Qualities and Terms of Protective Relaying, Basic Connection of Trip Circuit, Types of Relay Units, Relay Pick up, Reset or Drop out, Pick up/ Drop off Ratio, Construction and Working of Different Electromagnetic Relays [3]
Introduction, Fuse, Thermal Relays, Over Current Relays, Application of Definite Time & IDMT O.C. Relays for Protection of Feeder, Directional Over Current Relay, Limitations of O.C. Relays [1]
Simple Differential Protection, Zone of Protection and Actual Behavior of Simple Differential Protection, Percentage Differential Protection, Earth Leakage Protection[1]
Types of Faults, Over Current Protection, Percentage Differential Protection, Inrush Phenomenon, High Resistance Ground Faults in Transformers, Inter-turn Faults, Incipient Faults, Over-fluxing Phenomenon[1]
Drawbacks of O.C. Protection, Introduction to Distance Protection, Types of Distance Relay, Impedance, Reactance, MHO Relay, Performance of Distance Relay During Normal Load and Power Swing, Effect of Arc Resistance on Reach of Distance Relays, Comparison of Distance Relays, Distance Protection of Transmission line, Reasons for Inaccuracy of Distance Relay Reach, Three Step Protection, Trip contact configuration, 3-step protection of double and fed lines. [1]
Need for carrier aided protection of transmission lines, various options for carrier, Coupling and trapping the carrier into the desired line section, single line to ground coupling, line to line coupling, unit type carrier aided directional comparison relaying, carrier aided distance scheme for acceleration of zone II, transfer trip or inter trip, permissive inter trip, acceleration of zone II, pre-acceleration of zone II, phase comparison relaying (unit scheme) [1]
Various faults & abnormal operation conditions, stator & rotor faults, transverse differential protection, unbalanced loading, over speeding, loss of excitation, loss of prime mover [1]
Various faults & abnormal operation conditions, starting of induction motor, protection of small & large induction motor. [2]
Introduction, block diagram of numerical relay, numerical over current protection, numerical transformer protection, numerical distance protection of transmission line [1]
Introduction, Physics of arc phenomena, Maintenance of the arc, Losses from plasma, Essential properties of arc, Arc interruption theories. [4]
Introduction, Circuit breaker rating, Circuit constants & circuit conditions Re-striking voltage transient Characteristics of re-striking voltage, Interaction between the breaker & circuit, Current chopping, duties of switchgear.[4]
Automatic switch, Air-break circuit breakers, Oil circuit breakers, Single and multi break Construction, Air-blast circuit breaker, Performance of circuit breakers and system requirements, Modification of circuit breaker duty by shunt resistors, Power factor correction by series resistance, Comparative merits of different types of conventional circuit breakers, Modern trends, Vacuum circuit breakers, Sulphur hexafluoride (SF6) circuit breakers D.C. circuit breaker, auto-reclosing - definitions & features, 3-Phase versus 1-Phase auto-reclosing [4]
Magnetization curve of CT, Difference between measurement & protective CT, CT errors, calculation of CT accuracy, selection of CT, CT requirements for differential protection, specifications of CT, specifications of PT, CVT. [2]

Reference Books

SrTitleAuthorPublicationAmazon Link
1Fundamentals Of Power System ProtectionY. G. Parithankar & S. R. BhidePHI   
2Power system protection and switchgearOza, Nair, Mehta, MakwanaMcGraw Hill Education   
3Switchgear Protection and Power SystemsS. S. RaoKhanna Publication   
4Power System Protection And SwitchgearB. Ravindranath and M. ChanderNew Age International Private Limited   
5Art And Science Of Protective RelayingMassonWiley-Blackwell
6Computer relaying for power systemsA.G.Phadke, James S. ThorpWiley India Pvt Ltd   
7Protection and switchgearBhavesh Bhalja, R.P.Maheshwari, Nilesh hotaniOxford University Press   
8Power System ProtectionB. RamTMH Publication   
9Modern Power System ProtectionDivyeshOzaTMH Publication

Course Outcome

After learning the course the students should be able to:
1. Explain the purposes of protection, in relation to major types of apparatus, protection principle, dangers and criteria.
2. Choose and justify a suitable protection system for a specified application.
3. Analyze and compare specified protection systems
4. Compare merits of various principles, relay hardware and interrupting devices.
5. Compare the different type of circuit breakers performance based on which selection of circuit breaker can be made for a given application