60Hz, 380V, 4 pole 30kW induction motor,
When its driving under full load condition, the speed is 1746rpm,
input current 56.2A power factor 90%.
Under no-load condition, input current 17.3A, power factor
13.5%.
(In full load operation, assume that the mechanical loss is 25% of
the total loss and no other losses.)
a) Efficiency under full load
b) Find a rotor copper loss under full load
c) Core loss
d) Find a fixed stator copper loss under full load
e) Find the percentage of each stator copper loss, core loss, rotor
copper loss and machine loss in total losses.
answer -
a) 90.1%
b) 953W
c) 714W
d) 801W
e) 24.3%
60Hz, 380V, 4 pole 30kW induction motor, When its driving under full load condition, the speed...
For full load operation of 60Hz, 380V, 4 pole 30kW induction motor, the speed is 1746rpm, input current 56.2A power factor 90%. In no load operation, input current 17.3A, power factor 13.5%. In full load operation, assume that the mechanical loss is 25% of the total loss and no other losses. a) Iron loss load efficiency b) Find a rotor copper loss under full load c) Iron loss d) Find a fixed automatic hand under full load e) Find the...
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