In the operation and control of both naturally commutated and forced commutated SCR base converter, commutation plays an important role. The converters is / are ___________?

Related Mcqs:

1. Voltage commutation circuit can be converted into a current commutation by interchanging the positions of____________?

   A. Diode and capacitor
   B. Capacitor and SCR
   C. Inductor and capacitor
   D. Capacitor and load

2. During the commutation period in 3 phase converter, overlap time is_____________?

   A. Dependent on the load current
   B. Dependent on the voltage
   C. Dependent on both the load current and load voltage behind the short circuit current
   D. Independent on both the load current and load voltage

3. For commutation in three phase PAC, normally balanced three phase voltages VR, VY and VB are connected to the three legs of the converter via______________?

   A. Three inductances
   B. Three capacitances
   C. Three resistance
   D. Three transistors

4. During the commutation period in 3 phase converter, overlap time is____________?

   A. Dependent on the load current
   B. Dependent on the voltage
   C. Dependent on both the load current and load voltage behind the short circuit current
   D. Independent on both the load current and load voltage

5. In a flyback converter, the inductor of the buck-boost converter has been replaced by a_____________?

   A. Flyback capacitor
   B. Flyback resistor
   C. Flyback transformer
   D. Flyback transistor

6. 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___________?

   A. Turn on
   B. Not turn on
   C. Turn on if inductance is removed
   D. Turn on if pulse frequency us increased to two times

7. In current commutated DC-DC choppers, the voltage spike appears across the load when_____________?

   A. Voltage across the commutating inductances collapses
   B. The capacitance voltage adds to the supply voltage
   C. Both A. and B.
   D. None of these

8. In a load commutated DC – DC chopper, the capacitor has a_____________?

   A. Symmetric triangular voltage across itself
   B. Symmetric rectangular voltage across itself
   C. Symmetric trapezoidal voltage across itself
   D. Symmetric sinusoidal voltage across itself

9. The main objective of static power converters is to____________?

   A. Obtain an dc output waveform from a dc power supply
   B. Obtain an ac output waveform from a dc power supply
   C. Obtain an dc output waveform from a dc power supply
   D. Obtain an ac output waveform from a ac power suppl

10. The output current in PWM DC – DC converters is equal to___________?

    A. Average value of the output inductor current
    B. Product of an average inductor current and a function of duty ratio
    C. Either A. or B.
    D. None of these