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In: Electrical Engineering

A three-phase, 11.2-kW, 1750-rpm, 460-V, 60-Hz, four-pole, Y-connected induction motor has the following parameters: Rs =...

A three-phase, 11.2-kW, 1750-rpm, 460-V, 60-Hz, four-pole, Y-connected induction motor has the following parameters: Rs = 0.53 Ω, R’r = 0.38 Ω, Xs = 1.23 Ω, X’r = 1.45 Ω, and Xm = 25.2 Ω. The motor is controlled by varying both the voltage and frequency. The volts/hertz ratio, which corresponds to the rated voltage and rated frequency, is maintained constant.

a) Calculate the maximum torque, Tm and the corresponding speed, ꞷm for 60 Hz and 30 Hz.

b) Repeat (a) when Rs is negligible.

c) Draw a graph of torque–speed characteristics with volts/hertz control with the range of β between 0.4 and 1.

Expert Solution

Before solving relevant equations regarding the equivalent circuit of a induction motor is given below

moving on to answers

a)

b)

c)

hope this helps....reference made from theory and performance of electrical machines by JB Gupta

Manojponduru answered 4 months ago

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