ASSIGNMENT
CHAPTER: 1
Q: 1 Explain the arrangement of basic elements of protection using single line diagram. State &
explain desired functional characteristics of protection system.
Q: 2 Define ‘fault’. Explain the causes and consequences of fault.
Q: 3 Discuss normal operation of a power system and explain abnormal conditions of power system.
Q: 4 Explain back up protection. State reasons of failure of primary protection. Justify necessity of
back up protection & explain its types.
Q: 5 Justify the necessity of protective transformer & state advantages of using protective transformer.
Q: 6 Explain working principle and function of Current transformer and potential transformer.
Q: 7 Explain difference between instrument transformer and protective transformer.
Q: 8 Explain the construction of capacitor type and electromagnetic type PT.
Q: 9 State advantages of Neutral earthing & explain any ONE method.
Q: 10 Explain single line to ground fault in an isolated neutral system.
Q: 11 Explain the working and connection of Peterson coil for the grounding of Neutral.
Q: 12 Explain errors in CT.
CHAPTER: 2
Q: 1 Draw and explain construction and working of HRC Fuse.
Q: 2 Explain SF6 Circuit breaker.
Q: 3 List and explain any one method of arc extinction.
Q: 4 Explain construction, working and advantages of vacuum circuit breaker.
Q: 5 Explain air blast circuit breaker.
Q: 6 What are the reasons of arc formation. Explain how arc persist.
Q: 7 Explain low resistance arc interruption method.
Q: 8 Explain the breaking capacity and making capacity of circuit breaker.
Q: 9 Explain Drop out fuse.
CHAPTER: 3
Q: 1 State & explain principle of electromagnetic attraction relay & describe balanced beam type relay
with neat sketch.
Q: 2 Discuss gas operated relay used for protection of transformer.
Q: 3 State & explain working principle of electromagnetic induction relay & describe watt hour meter
type induction disc relay.
Q: 4 Discuss the following with respect to operation of a relay –
1. Plug Setting Multiplier.
2. Time Setting Multiplier.
3. I.D.M.T.Characteristics.
Q: 5 List advantages and disadvantages of static relays.
Q: 6 Explain working principle, construction and function of permanent magnet moving coil relay.
Q: 7 Explain any seven terms related to relay operation.
Q: 8 Draw the block diagram of microprocessor based over current relay and explain the function of
each block.
Q: 9 Write the maintenance schedule for a protective relay and ex plain in brief about primary current
injection test for relay.
Q: 10 Draw and explain directional power relay.
Q: 11 Describe directional over current relay and differentiate between direction o/c and directional
power relay.
Q: 12 Explain working of reactance type distance relay with diagram and its characteristics.
Q: 13 Explain working of MHO type distance relay with diagram and its characteristics.
CHAPTER: 4
Q: 1 Explain non directional time graded system for the protection of Transmission line.
Q: 2 Discuss Directional Time Graded Protection scheme for parallel feeder.
Q: 3 Explain Ring Mains Type Protective Scheme.
Q: 4 For the protection of Transmission line discuss the circulating current protection system.
Q: 5 Explain Transley Relay scheme for long transmission line.
Q: 6 With the help of diagram explain carrier current protection for long transmission line.
Q: 7 Give the difference between non-unit and unit type protection for line.
CHAPTER: 5
Q: 1 Draw and explain merz price protection scheme for motor winding.
Q: 2 Explain and draw differential protection scheme for the alternator.
Q: 3 Justify the statement: “The CTs should be connected in delta when power transformer winding is
connected in star and vice versa.”
Q: 4 Gives the protection of exciter failure of the alternator.
Q: 5 Write abnormalities occur in transformer and alternator. Also write protection provided against
them.
CHAPTER: 6
Q: 1 Define Over voltage. Discuss the causes of over voltage.
Q: 2 Give the external and internal reasons for over voltage and explain the effects of it on power
system. Which methods are used to reduce these effects.
Q: 3 With the neat sketch explain surge absorber.
Q: 4 Explain any two lightening arresters:
Horn gap arrester.
Protector tube type arrester
Valve type arrester.
Multi gap type arrester.
Lead Oxide type arrester.
Q: 5 Explain insulation coordination.
Q: 6 Explain protection against travelling waves.