(1) A two-pole, 50-Hz,6.6-, cylindrical rotor three-phase, star-connected synchronous motor is working under the constant field current and is drawing 1000W with a leading power factor of 0.8. The synchronous impedance is equal to the 1.5+12 phase. Calculate the power factor and output torque (shaft torque) when the input power increases to 1500W (Neglecting the rotational and mechanical losses).
(2) A 460-,60-Hz, 4-pole, three-phase induction machine with the following parameters is connected to a three-phase voltage source inverter (VSI) which implements the field-oriented control (FOC) scheme in synchronous reference frame. If the rotor speed is 1000rpm, the motor will deliver the maximum torque to the load under constant air-gap flux (equal to the machine-rated flux). What is the amplitude and frequency of the stator phase current?
A. Stator resistance: 0.087.
B. Stator leakage reactance: 0.302.
C. Magnetizing inductance: 13.08.
D. Rotor resistance: 0.228.
E. Rotor leakage reactance: 0.302.