Following are some of the multiple choice questions on the Power Electronics with answers that will help the students in developing their knowledge.
Power Electronics MCQ
1. Which device can be used in a chopper circuit?
2. Which of the following statements is correct in connection with the inverters?
3. The major advantage of using dual converters is that
4. In AC voltage controllers the
5. The shape of the output voltage waveform in a single PWM is
6. In an inverter, if the fundamental frequency is 50 Hz, if third harmonic is eliminated, then frequencies of other components in the output voltage wave, in Hz, would be
7. In case of current commutation of SCR
8. The values of duty cycle (α) lies between..........
9. In case of TRC (Time Ratio Control), _________ is varied
10. A single phase half wave controlled converter always operates in the ________ conduction mode.
11. When the temperature increases, the inter-base resistance (RBB) of a UJT ___________.
12. A voltage source inverter is normally employed when
13. In the ___________ type of chopper, two stage conversions takes place.
14. Which of the following is not a characteristic of UJT?
15. Dual converters provide
16. In voltage source inverters
17. In the three-phase bridge inverter, each step consists of
18. The load voltage of a chopper can be controlled by varying the..................
19. All the modern AC-DC converters are using GTOs instead of SCRs because
20. What are rheostats used for?
21. A single-phase semi-converter is having continuous conduction, as such each thyristor will conduct for an angle of
22. In the continuous conduction mode if the firing angle of the converter is increased beyond _________ degrees the converter operates in the _______ mode.
23. When a UJT is turned ON, the resistance between emitter terminal and lower base terminal ___________
24. The series-inverter control method is a/an..........
25. When the temperature increases, the intrinsic stand off ratio ___________.
26. What is the duty cycle of a chopper ?
27. In a half wave bridge inverter circuit, the power delivered to the load by each source is given by
28. For a single phase thyristor circuit with R load & firing angle α, the conduction angle can be given by
29. In a UJT, the p-type emitter is ___________ doped
30. After peak point, the UJT operates in the ___________ region.
31. The TRIAC is most sensitive in the _________ quadrants
32. A diac has ___________ semiconductor layers
33. What is the purpose of a resistor?
34. Cycloconverter converts
35. A PWM switching scheme is used with a three phase inverter to
36. A UJT has ___________.
37. When the emitter terminal of a UJT is open, the resistance between the base terminal is generally ___________.
38. In case of circulating current type dual converters, the reactor is inserted between
39. The ____________ region in a power diode increases its reverse voltage blocking capacity.
40. Single phase half controlled converters are most suitable for loads requiring ___________________ voltage and current.
41. The UJT may be used as ___________.
42. The Gate-Drain transfer capacitance of a MOSFET has large value in the ________________ region and small value in the ________________ region.
43. The device that does not have the gate terminal is ___________.
44. The four quadrant operation of dual converters can be obtained by
45. A single phase full bridge inverter can operate in load commutation mode if load consists of
46. A single full converter alone can given a
47. A UJT is sometimes called ___________ diode.
48. 1. In case of three-phase dual converter, one of the converter circuits is fired at an angle of 60°. For both the converter circuits to have equal average output voltage, what is the value of the firing angle for the other converter circuit?
49. The process of commutating a SCR by applying a reverse voltage to an SCR through a previously charged capacitor is called as
50. How does resistance affect current?
Enjoyed the Quiz. Share this with friends
