The use of capacitor phase separation has a better effect. It is possible to make the synthetic magnetic field of the motor close to the circular rotating magnetic field at a certain operating point of the motor, so as to obtain better working characteristics. In order to make the split-phase asynchronous motor obtain better starting performance or better operating characteristics or both, the required capacitance (value) is different, which can be divided into three types. (open loop) stepper motor It is an open-loop control motor that converts electrical pulse signals into angular displacement, and is widely used. In the case of non-overload, the speed and stop position of the motor only depend on the frequency and number of pulses of the pulse signal, and are not affected by the load change. When the stepper driver receives a pulse signal, it drives the stepper motor to rotate. A fixed angle, called “step angle”, the rotation of which runs step by step at a fixed angle.