 # When the voltage rises and falls, how does the speed of the Taichung motor change?

Update:07 Nov 2019
Summary:

The stator generates a rotating magnetic field under th […]

The stator generates a rotating magnetic field under the action of three-phase current. The frequency of the rotating magnetic field is related to the frequency of the alternating current. The standard frequency is 50 Hz. If the motor is a pair of magnetic poles, the rotating magnetic field frequency is 50 Hz, ie 3000 rpm. If the motor is two pairs of magnetic poles, the rotating magnetic field frequency is 25 Hz, that is, 1500 rpm; if the motor is three pairs of magnetic poles, the rotating magnetic field frequency is 50/3 Hz, that is, 1000 rpm; and the asynchronous motor rotor speed Both are smaller than the rotating magnetic field. For example, if the rotating magnetic field rotates at 3000 rpm, the rotor speed is generally 2950-2800 rpm. This is determined by the accuracy of the motor structure.

It can be seen that the speed of the motor is determined by the number of magnetic poles of the motor and the frequency of the alternating current. The situation is that the motor is in abnormal operation. The motor supply voltage is insufficient, the input power is not enough, and the load is still overloaded, causing the speed to fall below the required speed, and the speed is lowered. At this time, the voltage is increased to provide the speed.