Discussion
Home ‣ Electronics and Communication Engineering ‣ Power Electronics Comments
- Question
Which of these devices is used in relaxation oscillator?
Options- A. UJT
- B. SCR
- C. DIAC
- D. TRIAC
- Correct Answer
- UJT
- 1. In auxiliary commutated chopper, the charging and discharging time of capacitor
Options- A. are constant
- B. depend on load current
- C. may be constant or may depend on load current
- D. none of the above Discuss
- 2. In a single phase semiconverter feeding a highly inductive load, the load current is
Options- A. sinusoidal
- B. nearly constant
- C. absolutely constant
- D. rectangular Discuss
- 3. In a single phase full wave ac regulator feeding R-L load, the gate pulses
Options- A. are always of short duration
- B. may be of short duration
- C. should be rectangular with width (p - a)
- D. cannot be rectangular with width (p - a) Discuss
- 4. In a semi converter feeding a resistive load,
Options- A. the waveshapes of input voltage and input current are always similar
- B. the waveshapes of input voltage and input current can never be similar
- C. the waveshapes of input voltage and input current are similar only if firing angle is zero
- D. the waveshapes of input voltage and input current are similar only if firing angle is high Discuss
- 5. In a power diode the reverse recovery time is the time from the instant the forward current is zero to the instant when reverse recovery current has decayed to
Options- A. 50% of peak reverse current
- B. 25% of peak reverse current
- C. 10% of peak reverse current
- D. zero value Discuss
- 6. The difference between resonant commutation and self commutation is
Options- A. both these methods are based on entirely different principles
- B. in resonant commutation, the commutating elements carry load current but in self commutation, the commutating elements do not carry load current
- C. resonant commutation uses L and C but self commutation uses only capacitor
- D. none of the above Discuss
- 7. A cycloconverter for single phase operation has
Options- A. one positive group and one negative group converters
- B. two positive group and two negative group converters
- C. three positive group and three negative group converters
- D. any of the above Discuss
- 8. Which of these commutation methods uses two leads?
Options- A. Class A
- B. Class B
- C. Class C
- D. Class D Discuss
- 9. In a controlled rectifier a freewheeling diode is necessary if the load is
Options- A. inductive
- B. resistive
- C. capacitive
- D. any of the above Discuss
- 10. The total number of leads in MOS controlled thyristor is
Options- A. 2
- B. 3
- C. 4
- D. 2 or 3 Discuss
Power Electronics problems
Search Results
Correct Answer: depend on load current
Correct Answer: nearly constant
Correct Answer: should be rectangular with width (p - a)
Correct Answer: the waveshapes of input voltage and input current are similar only if firing angle is zero
Correct Answer: 50% of peak reverse current
Correct Answer: both these methods are based on entirely different principles
Correct Answer: one positive group and one negative group converters
Correct Answer: Class D
Correct Answer: inductive
Correct Answer: 3
Comments
There are no comments.More in Electronics and Communication Engineering:
Programming
Copyright ©CuriousTab. All rights reserved.