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15. In a synchronous machine, hunting is predominantly damped by a) mechanical losses in the rotor b) iron losses in rotor c) copper losses of stator d) copper losses of rotor View Answer Answer: d Explanation: The hunting is damped by the copper losses in the rotor. This set of Electrical Machines Multiple Choice Questions & Answers (MCQs) focuses on “Measurement of Xd and Xq”. 1. The d-axis reactance is determined by a) OCC & SCC b) OCC c) Slip test d) SCC View Answer Answer: a Explanation: Both the OCC as well as short circuit test are used to calculate the d-axis reactance. 2. The slip test is used to determine a) Xq b) Xd c) Xd and Xq d) None of the mentioned View Answer Answer: a Explanation: Slip test is used to determine the q-axis reactance. 3. During slip test it would be observed that i) Swing of ammeter is wide ii) Swing of voltmeter is wide a) i is true, ii is false b) i is false, ii is true c) both true d) both false View Answer Answer: a Explanation: The impedance during slip test is low so the voltage drop will be less and the current will be more. 4. Slip test must be conducted at low armature terminal voltage. This is due to a) avoiding error due to large slip b) avoiding error due to small slip c) avoiding heating d) all of the mentioned
