Permanent magnet low-speed synchronous motor is a novel synchronous motor that can directly obtain low speed and high torque without gear reduction device. The motor is a completely enclosed structure, and the magnetic field structure of the motor is axial magnetic field, which is completely different from the commonly used permanent magnet synchronous motor. The universal permanent magnet synchronous motor is radial magnetic field. Its performance is mainly for constant speed, low vibration, low noise and large starting torque, the motor in the load, start/stop, positive/reverse and the current change is small. The motor has a certain self-locking torque, such as the motor using DC excitation, can greatly increase the self-locking torque. The motor can instantly start/stop, forward/reverse and block rotation, and is widely used in industrial automation, electric valve actuators, machine feed and heat exchangers. With the special TDY controller GSI-02LF, stepless speed control can be obtained to meet the needs of various speed control systems.