B.TECH - Semester 4 electrical technology Question Paper 2020 (sep)
Practice authentic previous year university questions for better exam preparation.
Sample Questions
- 403 : ELECTRICAL TECHNOLOGY (MP) (2013 Scheme) Time : 3 Hours Max. Marks : 100 Answer all questions.
- Explain the principle of operation of DC motor.
- Draw and explain the torque-Speed and torque-armature current characteristics of DC series motor.
- Compare lap and wave winding.
- What is all day efficiency of transformer? Explain its significance.
- Explain auto transformer starting of induction motors.
- Explain the principle of operation of three phase induction motor.
- Why single phase induction motor is not self starting? Explain.
- What is synchronous condenser?
- Explain electric Arc Welding.
- What is regenerative braking? Explain. PART - B Answer any one full questions from each Module.
- (a) Derive the emf equation of a DC generator.
- (b) A four pole, lap wound DC shunt generator running at 1050 rpm has a useful flux per pole of 0.1 Wb . The armature winding consists of 210 turns each of $0.003 \Omega$ resistance. If the armature current is 45 A , calculate the induced emf and ter...
- (a) The open circuit characteristic of a DC shunt generator at 1500 rpm is given below. | $\mathrm{I}_{\mathrm{f}}(\mathrm{A}):$ | 0 | 0.4 | 0.8 | 1.2 | 1.6 | 2.0 | 2.4 | 2.8 | 3 | | :---: | :---: | :---: | :---: | :---: | :---: | :---: | :---: | :-...
- (i) no load emf fur a shunt field resistance of $100 \Omega$ (ii) Critical field resistance at 1500 rpm (iii) Open circuit characteristics and the open circuit voltage for a field resistance of $100 \Omega$ at 1000 rpm .
- (b) Derive the expression for torque in a DC motor.
- (a) Compare slip ring induction motors and squirrel cage induction motors. 10
- (b) Obtain the equivalent circuit of a $230 / 400 \mathrm{~V}, 50 \mathrm{~Hz}$, single phase transformer from the following test data : | | Voltage (V) | Current (A) | Power (W) | | :---: | :---: | :---: | :---: | | O.C. test (L.V. Side) : | 230 |...
- (a) Derive the expression for torque of a three phase induction motor. Obtain the torque-speed characteristics and explain each region of operation.
- (b) Draw the circle diagram for a $14.9 \mathrm{~kW}, 400 \mathrm{~V}, 50 \mathrm{~Hz}$, 4-pole three phase star connected induction motor from the following test data : | | Voltage (V) | Current (A) | Power (W) | | :--- | :---: | :---: | :---: | |...
- (a) Explain any two methods of starting synchronous motors.
- (b) Explain the working principle of
- (i) Capacitor start induction run motors (ii) Capacitor start and run motors
- (a) What is V curve? With neat sketch, explain the procedure of developing V curve.
- (b) With neat sketch, explain the working of any one type of stepper motor. 10 3
- (a) Explain the methods for speed control of DC motor. ..... 10
- (b) Draw the functional schematic of ac electric locomotives and explainfunctions of each.10
- (a) Compare the types of motors used in traction system. List out the advantages of each. ..... 10
- (b) What is electric braking? Explain the methods of electric braking. ..... 10