QI // The power input to a 440-V, 50-Hz, 3-plase, 6-pole induction motor is 60 KW. It is observed that the rotor e.m.f. makes 90 complete cycles per minute. The motor has a stator copper loss of Ikw and the fraction and windage loss of 2KW. Calculate (a) The rotor speed and rotor Cu loss per phase (b) The mechanical power developed and gross torque developed by rotor. (e) The rotor efficiency and motor efficiency. (d) The rotor resistance per phase if rotor current is 60 A.
Answers
Answered by
35
rotor copper loss
Rotor copper loss 0.04 x 2000 = 80
Forward slip S;
N, = 120 x f 120 x 50 P S;= 4 1500 - 1470 N, =2=S= 1.98
1500 rpm= 0.02
Backward slip =1500 (N, + N,)
Similar questions