Power Semiconductor Devices and Their Applications MCQs

Which of the following does permanent damage of an SCR?

In a 3-phase controlled bridge rectifier, with an increase of overlap angle, the output dc voltage

A single phase diode bridge rectifier supplies a highly inductive load. The load current can be assumed to be ripple free. The ac supply side current waveform will be

A dc to dc transistor chopper supplied from a fixed voltage dc source feeds a fixed resistive-inductive load and a freewheeling diode. The chopper operates at 1 KHz and 50% duty cycle. Without changing the value of the average dc current through the load, if it is desired to reduce the ripple content of load current, the control action needed will

An inverter capable of supplying a balanced three-phase variable voltage, not cause variable frequency output is feeding a three-phase induction motor rated for 50 Hz and 440 V. The stator winding resistance of the motor are negligibly small. During starting, the current in such can be avoided without sacrificing the starting torque be suitable applying

In a 3-phase, half-wave diode rectifier, the ratio of average output voltage to per phase maximum a.c. voltage as

If in a 3-phase, half-wave rectifier, if per phase input voltage is 200 V, then the average output voltage is

A voltage commutated chopper has the following parameters : Vs = 200 V, load circuit parameter la 2mH,5V.Commutation circuit parameter : L =25 pH, C = 50 p.F. For constant load current at 100A, the effective on period and peak current through the main thyristor respectively

In type A chopper source voltage is 100 V, d.c. on period = 100 RS, off-period = 150 itS and loadRLE consists of R = 20, L = 5 mH, E = 10V. For continuous conduction average output voltage and average output current for this chopper are respectively