Explore topic-wise MCQs in Power Electronics.

This section includes 7 Mcqs, each offering curated multiple-choice questions to sharpen your Power Electronics knowledge and support exam preparation. Choose a topic below to get started.

1.

A_THREE-PHASE_M-3_CONVERTER_IS_OPERATED_FROM_A_3-PHASE,_230_V,_50_HZ_SUPPLY_WITH_LOAD_RESISTANCE_R_=_10_‚ÄÖ√Ñ√∂‚ÀÖ√´¬¨‚ÀÇ._FIND_THE_VALUE_OF_FIRING_ANGLE_IF_AN_AVERAGE_OUTPUT_VOLTAGE_OF_50%_OF_THE_MAXIMUM_POSSIBLE_OUTPUT_VOLTAGE_IS_REQUIRED.?$#

A.
B. 92.7°
C. 67.7°
Answer» C. 67.7¬¨¬®‚Äö√†√ª
Discussion
2.

A_three-phase_half-wave_controlled_converter_is_fed_from_a_3-phase,_400_V_source_and_is_connected_to_a_load_which_takes_a_constant_current_of_36_A._Find,the_value_of_average_output_voltage_and_average_current_rating_of_SCR_for_a_firing_angle_of_30°.$#

A. 234 V, 36 A
B. 234 V, 12 A
C. 135 V, 36 A
D. 135 V, 12 A
Answer» C. 135 V, 36 A
Discussion
3.

A three-phase three-pulse converter would operate as a line commutated inverter whe?

A. 30° < α < 60°
B. 90° < α <180°
C. 90° > α
D. it can never operate as a line commutated inverter
Answer» C. 90¬¨¬®‚Äö√†√ª > ‚âà√≠¬¨¬±
Discussion
4.

A three-phase three pulse type controlled converter is constructed using 3 SCR devices. The circuit is supplying an R load with α < 30°. As such, each SCR device would conduct for$

A. 60° each cycle
B. 120° each cycle
C. 180° each cycle
D. 360° each cycle
Answer» C. 180¬¨¬®‚Äö√†√ª each cycle
Discussion
5.

In a three-phase, three-pulse, M-3 type controlled converter T1 starts to conduct at 30 + n°. At what angles do T2 and T3 start to conduct? Assume that the conduction sequence is T1-T2-T3.$

A. 2n° and 3n°
B. 150 + n° and 270 + n°
C. n° each
D. 30 + n° and 60 + n°
Answer» C. n¬¨¬®‚Äö√†√ª each
Discussion
6.

A three-phase, three-pulse, M-3 type controlled converter has firing angle for one of the SCRs set as 15°. This SCR would start conducting at$

A. 0°
B. 15°
C. 30°
D. 45°
Answer» E.
Discussion
7.

A three-phase, three-pulse, M-3 type controlled converter uses ____________ number of SCRs.

A. 1
B. 2
C. 3
D. 4
Answer» D. 4
Discussion