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In: Electrical Engineering

A 3 phase 460 V, 60 Hz, 4 pole, delta connected induction motor has the following...

A 3 phase 460 V, 60 Hz, 4 pole, delta connected induction motor has the following equivalent circuit parameters. Rs = 0.42 Ω, Rr = 0.23 Ω, Xs = Xr = 0.82 Ω. Xm = 22 Ω. The no load loss = 60 W and may be assumed constant. The rotor speed is 1750 rpm. Use the approximate equivalent circuit ( i.e. the Xm branch is at the very left of the circuit) determine the following

a. the synchronous speed

b. the slip s

c. the input current I1

d. the input power

e. the input power factor of the supply

f. the air gap power Pag

g. the rotor copper loss

h. the developed torque

i. the efficiency

j. the slip for maximum torque

k. the maximum developed torque

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