The difference between synchronous and asynchronous motors
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What are the differences between synchronous and asynchronous motors and what equipment are they used in?
Asynchronous motors have greater power but inaccurate speed, while synchronous speeds are more accurate. Generally, motors are three-phase asynchronous motors, and synchronous motors are used in places with smaller power.
The stator windings of synchronous motors and asynchronous motors are the same, the main difference lies in the structure of the rotor. The rotor of a synchronous motor has a DC excitation winding, so an external excitation power supply is required to introduce current through a slip ring. ； The rotor of an asynchronous motor is a short-circuited winding that generates current by electromagnetic induction.
Synchronous motors are mostly used in large generators. Asynchronous motors are almost exclusively used in electric motor applications. Synchronous motors can flexibly adjust the voltage and current phase on the input side through excitation, that is, the power factor ； The power factor of asynchronous motors is not adjustable and is used in some large factories. Synchronous motors are expensive to build and require a lot of maintenance work.
The upstairs is too incomplete； 1) The speed of the synchronous motor is accurate. The speed of the equipment driven by the asynchronous motor is a few turns slower. ； 2) "Synchronization is used in places with low power" is exactly the opposite, because synchronous motors have a large power factor and high efficiency, and are suitable for use on high-power motors, but the cost is slightly higher and an excitation cabinet is required.
The number of revolutions of a synchronous motor is fixed during normal operation and does not change due to changes in load. The number of revolutions of an asynchronous motor is not fixed during normal operation, but will change slightly due to changes in load. Synchronous motors have complex circuits and reversible energy (the motor and generator are theoretically interchangeable) and are often used as generators.