How linear motors work

A linear motor is a transmission that directly converts electrical energy into linear motion mechanical energy without the need for any intermediate conversion mechanism. It can be seen as a rotary electric machine cut in a radial direction and spread out into a plane.

The side evolved from the stator is called the primary, and the side evolved from the rotor is called the secondary. In practical applications, the primary and secondary are manufactured to different lengths to ensure that the coupling between the primary and secondary remains unchanged within the required stroke range. Linear motors can be short primary long secondary, or long primary short secondary. Taking into account manufacturing costs and operating costs, short primary long secondary are generally used.

Linear motors work similarly to rotary motors. Take a linear induction motor as an example: when AC power is applied to the primary winding, a traveling wave magnetic field is generated in the air gap, and the secondary is cut by the traveling wave magnetic field to induce electromotive force and generate a current. The magnetic field interacts to generate electromagnetic thrust. If the primary is fixed, the secondary performs linear motion under thrust; otherwise, the primary performs linear motion.