Motors are devices that convert electrical energy into mechanical energy. It uses a energized coil (that is, a stator winding) to generate a rotating magnetic field and acts on a rotor squirrel-cage closed aluminum frame to form a magnetoelectric rotational torque. The electric motor is divided into a direct current motor and an alternating current motor according to the use of the power source. The electric motor in the electric power system is mostly an alternating current motor, and may be a synchronous motor or an asynchronous motor (the stator magnetic field speed of the motor and the rotational speed of the rotor are not kept at the synchronous speed). The motor is mainly composed of a stator and a rotor, and the direction in which the energized wire is subjected to the force in the magnetic field is related to the direction of the current and the direction of the magnetic induction line (the direction of the magnetic field). The working principle of the motor is that the magnetic field acts on the current to force the motor to rotate.