Question

A 25-hp three-phase induction motor
operates for a 440-Vrms (line-to-line)
three phase source and draws a line
current of 35 A rms at a power factor of
83 percent lagging under rated full load
conditions. The full load speed is 1750
rpm.
​

Answer 1

Explanation:

Step 1

This is a unity negative feedback system. For this system to oscillate at some frequency, we need two closed loop poles on the imaginary axis. The characteristics equation (C.E) of the system is shown below: