Effect of change in Frequency in Induction Motor

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The frequency of the supply voltage applied to an induction motor has a direct effect on the motor’s speed and torque. The speed of an induction motor is given by the equation:

Speed = (120 x Frequency) / Number of Poles

This equation shows that the speed of an induction motor is directly proportional to the frequency of the supply voltage. Therefore, if the frequency of the supply voltage is increased, the speed of the motor will increase. Conversely, if the frequency of the supply voltage is decreased, the speed of the motor will decrease.

The torque produced by an induction motor is also affected by the frequency of the supply voltage. The torque produced by an induction motor is proportional to the square of the supply voltage and inversely proportional to the frequency of the supply voltage. Therefore, if the frequency of the supply voltage is increased, the torque produced by the motor will decrease. Conversely, if the frequency of the supply voltage is decreased, the torque produced by the motor will increase.

In summary, changing the frequency of an induction motor has a direct effect on its speed and torque.

In next part I will explain with practical scenario which will help you to understand in better way that why should we be more careful while selecting the motor for a particular voltage and frequency.

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