Q1. A 3.phase full wave controlled rectifier is fed from 3-phase, 400V,50HZ source and is connected to load taking a constant current of 35A. (a) Draw the waveform of output
voltage. (b) Calculate average value of load voltage for a firing angle of 20°
(c) average load power,
(30 mark)
Q2. Explain with necessary equation and drawing the principle operation of the boost
chopper
(35 mark)
Q3. A square wave output single phase bridge inverter supplies an 80 resistor with 40mH
inductance load. Load fundamental rms voltage is 135V at 60Hz. Calculate:
(a) voltage of the dc supply.
(b) rms value of load voltage, load current and third harmonic voltage.
(c) Load power
(35 mark)