Changing the parameters of a three-phase asynchronous motor. Scheme, description

ENCYCLOPEDIA OF RADIO ELECTRONICS AND ELECTRICAL ENGINEERING
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Changing the parameters of a three-phase asynchronous motor. Encyclopedia of radio electronics and electrical engineering

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Encyclopedia of radio electronics and electrical engineering / Electric motors

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As you know, our electrical networks do not have constant current parameters. Therefore, it is necessary to know how they change motor parameters under conditions other than nominal.

If the voltage in the power supply network of a three-phase asynchronous motor decreases (while maintaining the rated frequency of the alternating current), its torque decreases and the efficiency drops. As the voltage increases (while maintaining the rated frequency of the current), the torque increases, which leads to overheating of the motor and a decrease in efficiency.

As they say, changing the places of the terms does not change the sum. Therefore, if the voltage remains constant and the frequency of the alternating current decreases, then the efficiency still deteriorates: the engine speed decreases and it begins to heat up. An increase in the frequency of alternating current while maintaining the rated voltage leads to a similar result.

Author: Korshevr N.G.

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