1. Explain what is meant by standstill reactance of induction motor rotor. How does it vary with speed?
2. The stator of a slip-ring induction motor with slip-ring terminals open-circuited has a stator excited from 3-phase source. The rotor is run by a prime mover. What will be the frequency of rotor induced emf at the following speeds?
(a) Half synchronous speed in the same direction as the air-gap field (AGF)
(b) Half synchronous speed in opposite to AGF
(c) At synchronous speed in opposite direction to AGF