How is the speed of a 3-phase induction motor varied?

How is the speed of a 3-phase induction motor varied?
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1 Answer

Answer :

The speed of a normal 3-phase induction motor is a function of the frequency of the supply voltage. Changing the speed of such a motor hence requires building a 3-phase power frequency convertor. This can be realised by using power MOSFETs (or IGBTs) capable of handling high voltages and fast switching speeds.
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