Question 10.1: Calculate the ratio of starting torque to full-load torque o...

Electrical Machines [EXP-707]

Calculate the ratio of starting torque to full-load torque of a 3-phase induction motor having short-circuit current 4 times the full-load current with a full-load slip of 3%.

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Hence, $I_{sc } = 4 I_{fl}; S_{f} = 3\% = 0.03$

Ratio of starting to full-load torque, $\frac{T_{st}}{T_{fl}} = \left\lgroup\frac{I_{sc}}{ I_{fl}}\right\rgroup^{2} \times S_{f} = \left(4\right)^{2} \times 0.03 = \mathbf{0.48}$

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