Q-In a single-phase half wave inverter ________ SCR(s) are/is gated at a time.
a) one
b) two
c) three
d) none of the mentioned
………….
Answer: a
Explanation: Only one SCR is gated at a time, gating the both of them will short the supply.
Q-_________ based inverters do not require self-commutation.
a) IGBT
b) GTO
c) PMOSFET
d) SCR
………….
Answer: d
Explanation: All the devices can be turned off by their gate/base singles expect SCR. SCRs require external commutation circuits
Q-Line-commutated inverters have
a) AC on the supply side and DC on the load side
b) AC on both supply and load side
c) DC on both supply and load side
d) DC on the supply side and AC on the load side
…………..
Answer: b
Explanation: Line-commuted inverters are actually phase-controlled converters operated in the inverting mode. They cannot act as standalone inverters as they require a AC supply. It is to be noted that “line commutated inverter” is not the conventional inverter. The conventional inverters are forced or load commutated inverters.
Q-Below given is a
a) SCR based inverter
b) MOSFET based inverter
c) IGBT based inverter
d) None of the mentioned
……………….
Answer: b
Explanation: It is a half wave inverter with MOSFET switches. The diodes are used to bypass the negative current.
Q-The output current wave of a single-phase full bridge inverter on RL load is
a) a sine wave
b) a square wave
c) a triangular wave
d) constant dc
………….
Answer: c
Explanation: On RL load, the SCRs are revised biased due to the voltage drops across the diodes and negative current flows.
Q-Single-phase full bridge inverters requires
a) 4 SCRs and 2 diodes
b) 4 SCRs and 4 diodes
c) 2 SCRs and 4 diodes
d) 2 SCRs and 2 diodes
………….
Answer: b
Explanation: Full bridge inverters require 4 SCR and 4 diodes along with a two wire dc source.
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