What is the difference between a synchronous and asynchronous motor?

Synchronous motors are characterized by their ability to maintain a constant speed that is directly proportional to the supply frequency. This means that the speed of a synchronous motor does not change with variations in load once it reaches its operating conditions. As a result, these motors are particularly suited for applications requiring precise speed control.

In contrast, asynchronous motors, also known as induction motors, do not maintain a constant speed relative to the supply frequency. Their speed can vary depending on the load, resulting in slip — a phenomenon where the rotor speeds slightly less than the synchronous speed. This fundamental difference in operational behavior underlies the distinction between the two types of motors.

Understanding this difference is crucial for selecting the appropriate type of motor for specific applications, particularly those that demand consistent timing or speed regulation.