Question

Problem # 2: Induction Motor Analysis Using The Thevenin Theorem [37 points] A three-phase, two pole, 25hp, 460V (line-line), 60Hz, wye-connected, squirrel-cage induction motor has the following per-phase parameters: Ri 0.53 Ohm X2 0.80 Ohm Xi 1.80 Ohms R2 0.30 Ohm Re- 400 Ohms Xm 25.0 Ohms You cannot use any approximate circ uit or any approximation in the calculations. (1) Determine the parameters of the Thevenin equivalent circuit. Draw the equivalent circuit with the appropriate parameter values indicated on the diagram [10 points) nt circuit, calculate the starting rotor current and the starting torque [10 points] (3) Using the Thevenin equivalent circuit, calculate the maximum torque and corresponding output developed mechanical power. [10 points) (4) If the maximum torque is to be realized at the starting condition, what is the required additional rotor resistance? 17 points]

Answer 1

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