Top 250+ Solved Power Electronics MCQ Questions Answer
Q. A fully controlled converter uses
a. diodes only
b. thyristors only
c. both diodes and thyristors
d. none of the mentioned
Q. In a B-2 type full controlled bridge converter
a. one SCR conducts at a time
b. two SCRs conduct at a time
c. three SCRs conduct at a time
d. four SCRs conduct at a time
Q. In a step down chopper, if Vs = 100 V and the chopper is operated at a dutycycle of 75 %. Find the output voltage.
a. 100 V
b. 75 V
c. 25 V
d. none of the mentioned
Q. Find the output voltage for a step-up chopper when it is operated at a dutycycle of 50 % and Vs = 240 V.
a. 240 V
b. 480 V
c. 560 V
d. 120 V
Q. In the method of phase control, the phase relationship between ___ & ___ iscontrolled by varying the firing angle
a. supply current, supply voltage
b. end of the load current, end of the load voltage
c. start of the load current, start of the load voltage
d. load current, load voltage
Q. The AC voltage controllers are used in __________ applications.
a. power generation
b. electric heating
c. conveyor belt motion
d. power transmission
Q. A cycloconverter is a:
a. Frequency changer from higher to lower frequency with one-state conversion
b. Frequency changer from higher to lower frequency with two-stage conversion
c. Frequency changer from lower to higher frequency with one-stage conversion
d. Either a or c
Q. IGT stands for
a. Insulated gate bipolar transistor
b. Insulated gate bidirectional transistor
c. Inductive gate bipolar transistor
d. Inductive gate bidirectional transistor
Q. In a silicon controlled rectifier, the load is connected
a. Across anode
b. In series with anode
c. Across cathode
d. In series with cathode
Q. Anode of an operational SCR is
a. Always positive w.r.t cathode
b. Always negative w.r.t anode
c. Always positive w.r.t anode
d. Always negative w.r.t cathode
Q. If the gate voltage of an SCR is removed, then the
a. anode current decreases
b. anode current does not decrease at all
c. anode current increases
d. cathode current increases
Q. In a single phase full wave rectifier, during blocking state the peak inversevoltage of diode is
a. V m
b. 2 V m
c. V m / 2
d. 4 V m
Q. In a full wave rectifier, the rectification ratio is approximately equal to
a. 61%
b. 71%
c. 81%
d. 91%
Q. For power output higher than 15 kW, the suitable rectifier is
a. Single phase
b. 3 phase
c. Poly phase
d. Only (b) and (c)