STUPIDSID
1 (a)
What are the important applications of power electronics?
6 M
1 (b)
Explain peripheral effects of power converter system.
6 M
1 (c)
Explain different types of power electronic converter circuits.
8 M
2 (a)
Draw the equivalent model of BJT and explain the switching characteristics of power transistor.
8 M
2 (b)
Compare the BJT and MOSFET.
5 M
2 (c)
Discuss the different methods of providing isolation of gate drive circuits from power circuit.
7 M
3 (a)
Explain the two transistor analogy of an SCR. Derive an expression for anode current. Also explain the process of regeneration cycle.
10 M
3 (b)
Write a short note on dv/dt and di/dt protection.
5 M
3 (c)
A UJT is connected across a 20 V DC supply. A valley and peak point voltages are 1 V and 15 V. The period of relaxation oscillation is 20 ms. Find the value of charging capacitor, if a charging resistor of 100 kΩ is used.
5 M
4 (a)
Explain with the help of wave forms,1-Φ semi-converter (half bridge converter) with R-load. Derive an expression for V0(avg) and V0(rms).
10 M
4 (b)
A single phase dual converter is operated from 120 V, 50 Hz supply and the load resistance R=10Ω the circulating inductance LT=40 mH delay angle are α1=60° and α2=120°. Calculate the peak circulating current and peak current of converter.
6 M
4 (c)
What is the use of wheeling diode in a converter circuit?
4 M
5 (a)
Explain the self communication with the help of neat sketch and obtain the expression for the capacitor voltage and current.
10 M
5 (b)
Distinguish between the natural and forced communication.
5 M
5 (c)
In the parallel capacitor turn-off circuit shown in fig.Q5(c), the main SCRT, is to be reverse biased for at least 40 µs for proper communication and holding current of auxiliary SCRT2 is 2 mA. Determine the value of R and C.
5 M
6 (a)
With the help of circuit diagram, explain the operation of single phase AC regulator using ON-OFF control. Derive the expression for ms value of load voltage.
10 M
6 (b)
Explain the single phase bidirectional AC voltage controller with resistive load with waveform.
10 M
7 (a)
With neat circuit diagram and explain the four quadrant chopper.
8 M
7 (b)
With neat circuit diagram, explain the principle of operation of step up chopper.
8 M
7 (c)
A chopper circuit is operating on Time Ration Control (TRC) at a frequency of 2 kHz on a 460 V supply of the load voltage of 350 V. Calculate the conduction period of the thyristors in each cycle.
4 M
8 (a)
Explain the performance of inverters.
6 M
8 (b)
With a neat circuit diagram, explain the principle of variable DC link.
8 M
8 (c)
Write a short note on CSI (Current Source Inverter).
6 M
More question papers from Power Electronics