PART-B

4 Describe the working of a single phase full converter both in the rectifier and inverter
mode with RLE load, Illustrate with waveforms for source voltage, load voltage,
source current and load current. Assume continuous conduction. (9)

5 Explain the operation of a Boost Converter with circuit diagram and relevant
waveform. Derive the expression for L and C. (9)

6 a) Discuss the effect of source inductance in a fully controlled converter. Draw the
relevant waveforms. http*./*'uww.kiilonline.com (5)
b) A buck converter has an input voltage, Vs=15 V. The required average output
voltage 5 V and the peak to peak output ripple voltage is 10 mV. The switching
frequency is 20 KHz The peak to peak ripple current of inductor is limited to 0.5 A.
Determine 1) the duty cycle ii) the filter inductance iii) the filter capacitance iv) the
critical values of LandC (4)

PART-C

7 a) Draw the circuit diagram and explain the operation of a forward converter for
continuous conduction mode. Give relevant waveforms. Derive the voltage transfer
ratio. (8) 0) Explain the advantages of flyback converter. (4)

8 Explain the operation of 3 phase inverter with 1 80 ° conduction with circuit diagram.

Draw the timing diagrams of the switches and the resulting phase and line voltages.
(12)

9 a) Describe a single phase capacitor commutated current source inverter with purely
resistive load. (6) 0) Explain the operation of a push-pull 60-60 converter with circuit
diagram and relevant waveforms. (6)