Question

The starting torque of a three-phase synchronous motor is increased when SE O ou h atic tio co e rotor electromagnet is turned on. a. b. the rotor electromagnet is turned off. c, the power factor of the ac power network is unity. d. dc power is applied to one of the stator windings. 2. When a synchronous motor without load is connected to a three-phase ac power network, the resulting power factor depends on a. the speed of the motor. b. the active power consumed by the motor c. the amount of field current. d. the line current. le 3. Reactive power in a synchronous motor without load is minimum when the a. line current is maximum. b. line current is minimum. C. line current equals the field current d. field current is minimum. 4. Synchronous condenser is another name for a. an asynchronous motor. b. a squirrel-cage motor. c. a split-phase motor. d. a synchronous motor operating without load. 5. The squirrel cage in a synchronous motor a. minimizes the motor line current. b. prevents saturation of the rotor electromagnet. c. allows the motor to start when ac power is applied to the stator windings. d. makes the motor operate as a synchronous condenser.

Answer 1

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