Power Electronics A single phase one pulse controlled circuit has a resistance R and counter emf E load 400 sin(314 t) as the source voltage. For a load counter emf of 200 V, the range of firing angle control is 30° to 150°. 60° to 120°. 30° to 180°. 60° to 180°. 30° to 150°. 60° to 120°. 30° to 180°. 60° to 180°. ANSWER DOWNLOAD EXAMIANS APP
Power Electronics What happen due to high di / dt? None of these. Local hot spot. Insulation failure. Breakdown of junction. None of these. Local hot spot. Insulation failure. Breakdown of junction. ANSWER DOWNLOAD EXAMIANS APP
Power Electronics A thyristor string is made of a no. of SCR connected in series and parallel. The string have volume and current of 11 KV and 4 KA. The voltage and current rating of available SCRs are 1800 V and 1000 A. For a string efficiency of 90 % let the number of SCRs in series and parallel are a and b respectively. Then the value of a and b will be 6, 4. 5, 7. 7, 5. 4, 6. 6, 4. 5, 7. 7, 5. 4, 6. ANSWER DOWNLOAD EXAMIANS APP
Power Electronics The turn-on time of an SCR with inductive load is 20 µs. The puls train frequency is 2.5 KHz with a mark/space ratio of 1/10, then SCR will Turn on if pulse frequency us increased to two times. Turn on. Turn on if inductance is removed. Not turn on. Turn on if pulse frequency us increased to two times. Turn on. Turn on if inductance is removed. Not turn on. ANSWER DOWNLOAD EXAMIANS APP
Power Electronics An SCR is considered to be a semi controlled device because it can be turned ON but not OFF with a gate pulse. it can be turned OFF but not ON with a gate pulse. it conducts only during one half cycle of an alternating current wave. it can be turned ON only during one half cycle of an AC. it can be turned ON but not OFF with a gate pulse. it can be turned OFF but not ON with a gate pulse. it conducts only during one half cycle of an alternating current wave. it can be turned ON only during one half cycle of an AC. ANSWER DOWNLOAD EXAMIANS APP
Power Electronics Which one is most suitable power device for high frequency (>100 KHz) switching application? Power MOSFET. BJT. Microwave transistor. Schottky diode. Power MOSFET. BJT. Microwave transistor. Schottky diode. ANSWER DOWNLOAD EXAMIANS APP
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