Q. In a 3 phase full wave regulator feeding a star connected resistance load, firing angle is 75°. Then the number of thyristors conducting at one time is

View solution

Q. In a single phase full wave ac regulator using two thyristors only, the gate circuits of the two thyristors

View solution

Q. In a single phase half wave converter feeding resistive load and full wave converter (M - 2 connection) feeding a resistive load the circuit conditions are similar. The firing angle is α. Then the waveshapes of voltages across thyristors

View solution

Q. In a 3 phase full converter feeding a highly inductive load, the average load current is 150 A. The peak current through thyristor is

View solution

Q. Multiphase choppers are used in

View solution

Q. In a single phase converter using a centre tapped transformer and with a highly inductive load, the firing angles is α. Each thyristor conducts for a period

View solution

Q. In a parallel inverter

View solution

Q. A step up chopper can give an output voltage

View solution

Q. The specified maximum junction temperature of thyristors is about

View solution

Q. A bridge type single phase cycloconverter changes the frequency f to f/3. Then one half wave of output contains

View solution

Q. A half bridge inverter

View solution

Q. A 3 phase series inverter has

View solution

Q. HVDC systems are preferable for only long distances.

View solution

Q. Surge current rating of an SCR is

View solution

Q. Which of the following devices has metal-silicon junction?

View solution

Q. In a series inverter

View solution

Q. When a power diode is conducting, the voltage drop across it is about

View solution

Q. In thermal ohm's law, temperature and power loss are analogous to

View solution

Q. A string of series connected thyristors needs equalising circuit to

View solution

Q. A surge voltage

View solution