Exercise :: Power Electronics - Section 2
| 1. | A dc circuit breaker must use |
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Answer: Option B Explanation: Natural commutation is possible only in ac circuits. |
| 2. | In a single phase full wave regulator feeding R-L load, the minimum firing angle can be zero. |
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Answer: Option A Explanation: Range of control of a is 0 ≤ a ≤ p. |
| 3. | An RC snubber circuit is used to protect a thyristor against : |
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Answer: Option C Explanation: Especially high |
during switching.| 4. | A DIAC has two terminals, anode and cathode. |
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Answer: Option B Explanation: They are designated as T1 and T2 because diac can conduct in both directions. |
| 5. | A single phase semiconverter has a freewheeling diode. If the firing angle is a and the load is purely resistive, the periods of conduction and freewheeling respectively are |
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Answer: Option A Explanation: Freewheeling diode conducts only when load is inductive. If load is purely resistive free wheeling diode does not come into operation. |