In: Electrical Engineering
A 50-Hz, 440-V, 2 pole wye connected induction motor is rated at
75 kW. The equivalent
parameters are as follows:
RS = 0.075 Ω RR’ = 0.065 Ω
XS = XR’ = 0.17 Ω Xm = 7.2 Ω
The losses associated with the machine are field and winding,
miscellaneous and
core loss with values of 1 kW, 150 W and 1.1 kW, respectively. For
a slip of 4 %,
determine
a) The line current. (150.39 -23.08 A)
b) The stator power factor. (0.9199 lagging)
c) The stator copper losses (5.089kW)
d) The air-gap power (99.249 kW)
e) The developed power (95.279kW)
f) The induced torque (315.91N.m.)
g) The motor speed in rad/s (301.6 rad/s)
h) The load torque (312.10 N.m.)
i) The overall machine efficiency (89.3%)