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EndsemNov 20242019 patternBE Electrical

Switchgear and Protection SPPU Endsem Question Paper Nov 2024

All 8 questions from this SPPU endsem paper, as printed. Read them here or open the PDF.

Open the PDFMost repeated Switchgear and Protection questions
Subject code
403148
Pattern
2019 pattern
Exam
Endsem
Session
Nov 2024
Max. marks
70
Time
2½ Hours
Semester
VIII
Paper code
[6354]-518

Printed for: B.E. (Electrical Engineering )

Instructions to the candidates

  1. Solve Q1 or Q2, Q3 or Q4, Q5 or Q6, Q7 or Q8.
  2. Figures to the right indicate full marks.
  3. Neat diagrams must be drawn wherever necessary.
  4. Assume suitable additional data, if necessary.
  5. Use of non-programmable calculator is allowed.

Questions

  1. Q1

    1. a)

      Explain following ratings of circuit breaker. i) Making capacity ii) Breaking capacity iii) Short time rating

      Also asked:Nov 2025 ·May 2025 ·May 2024

      [6]
    2. b)

      State disadvantages of Air circuit breaker

      Also asked:May 2025

      [4]
    3. c)

      State properties of SF 6 gas

      [8]

  2. Q2

    1. a)

      Write a note on Auto - reclosing

      [4]
    2. b)

      Explain advantages of GIS over conventional substation

      [6]
    3. c)

      An 11 KV, 500 MVA, 3 sec CB suddenly closes on occurring of fault. Determine i) Symmetrical breaking current ii) Asymmetrical breaking current assuming 50% DC component iii) Peak making current iv) Short time current rating

      Also asked:Nov 2025 ·May 2025

      [8]

  3. Q3

    1. a)

      Draw block diagram of PMU.

      [3]
    2. b)

      State and Explain Sampling Theorem.

      [6]
    3. c)

      State advantages and disadvantages of static relay.

      Also asked:May 2024 ·Nov 2023

      [8]

  4. Q4

    1. a)

      State advantages of Numerical Relay.

      [3]
    2. b)

      Explain Antialising Filter with neat diagram.

      [6]
    3. c)

      Draw and explain block diagram of Numerical Relay. 2

      Also asked:Nov 2025 ·May 2025

      [8]

  5. Q5

    1. a)

      What are the problems encountered in differential protection.

      [4]
    2. b)

      Explain overload protection in case of three phase Induction motor.

      [6]
    3. c)

      The neutral point of a 3 phase , 20 MVA, 11 KV alternator is earthed through a resistance of 5 ohm. The relay is set to operate when there is an out of balance current of 1.5 Amp. The CT’s have a ratio of 1000/5. What is the percentage of winding protected? Also calculate the earthing resistance required to protect 90% of the winding.

      [8]

  6. Q6

    1. a)

      This part has equations that don’t show as text. Open the PDF to read it.

      [4]
    2. b)

      Explain short circuit protection in case of three phase Induction motor.

      [6]
    3. c)

      What is transverse protection of an alternator? What type of fault is this scheme of protection employed? With a neat sketch discuss the working principle of this scheme.

      [8]

  7. Q7

    1. a)

      What do you mean by term Directional and Non - Directional overcurrent relay.

      Also asked:Nov 2025

      [3]
    2. b)

      Explain the effect of Arc resistance on. i) Impedance relay ii) MHO relay

      Also asked:Nov 2025 ·May 2025 ·May 2024 ·Nov 2023 ·May 2023

      [6]
    3. c)

      Draw block diagram of PLCC scheme used for transmission line protection and briefly explain its components.

      Also asked:Nov 2023

      [8]

  8. Q8

    1. a)

      Draw flowchart of Numerical algorithm.

      Also asked:May 2025

      [3]
    2. b)

      Explain three stepped distance protection.

      Also asked:Nov 2025 ·May 2024 ·May 2023

      [6]
    3. c)

      Draw the characteristics of the following distance relays in the R-X diagram and explain. i) Mho - relay ii) Reactance relay iii) Quadrilateral - relay iv) Impedance-relay 

      [8]