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In: Electrical Engineering

A 60-Hz, 208-V, 2 pole wye connected induction motor is rated at 15hp. The equivalent parameters...

A 60-Hz, 208-V, 2 pole wye connected induction motor is rated at 15hp. The equivalent
parameters are as follows:
RS = 0.2 Ω RR’ = 0.120 Ω
XS = XR’ = 0.41 Ω Xm = 15 Ω
The machine has negligible miscellaneous losses but experiences mechanical loss
and core loss of 250 W and 180 W, respectively. For a slip of 5 %, determine
a) The line current. (44.8  -25.5  A)
b) The stator copper losses (1.205 kW)
c) The air-gap power (13.4 kW)
d) The converted power (12.73 kW)
e) The induced torque (35.5 N.m.)
f) The motor speed in rad/s (358 rad/s)
g) The load torque (34.3 N.m.)
h) The overall machine efficiency (84.5 %)

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