Q. 39 The speed of a 4-pole induction motor is controlled by varying the supply frequency while maintaining the ratio of supply voltage to supply frequency (V/f) constant. At rated frequency of 50 Hz and rated voltage of 400 V its speed is 1440 rpm. Find the speed at 30 Hz, if the load torque is constant
(A) 882 rpm
(B) 864 rpm
(C) 840 rpm
(D) 828 rpm
Answer:(C)
Explanation:
