A 440-V, 3-φ 50-Hz, 4 poles, 37.3 kW, Y-connected induction motor has the following parameters: R1=...

A 440-V, 3-φ 50-Hz, 4 poles, 37.3 kW, Y-connected induction motor has the following parameters:

R1= 0.1 Ω, X1 = 0.4 Ω , R2′ = 0.15 Ω , X2′ = 0.44 Ω

Motor has stator core loss of 1250 W and rotational loss of 1000 W. It draws a no-load line current of 20 A at a p.f. of 0.09 (lag). When motor operates at a slip of 3%, calculate

a. input line current and p.f. [57.4@29°A, 0.875 lag]

b. electromagnetic torque developed in N-m [230 Nm]

c. output and [34075 W]

d. efficiency of the motor. [88.7%]

Expert Solution

Manojponduru answered 10 months ago

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