Electrical energy conversion is achieved by the synchronous rotation of the stator winding and the rotor permanent magnet magnetic field. Its rotor adopts a convex or embedded permanent magnet structure, which has the characteristics of high efficiency, high power factor and low loss, and is widely used in CNC machine tools, robots, new energy vehicles and rail transit.
The stator structure of this motor is similar to that of traditional motors, eliminating the excitation device. The power density and torque-to-inertia ratio are significantly better than those of asynchronous motors. The single-unit capacity exceeds 1000KW, and the speed ranges from 0.01 to 300000r/min [1] [5]. The power range of the product covers 4.4KW-408.4kW, and the torque can reach 485NM. It is equipped with a variety of encoders and has passed CE/UL certification. The control system adopts field-oriented control (FOC) and vector control technology, and realizes closed-loop regulation of position, speed and torque through DSP [6]. With the improvement of NdFeB material performance, products are developing towards higher power and intelligence. In high-speed rail permanent magnet traction systems, the conversion efficiency is more than 3% higher than that of asynchronous motors, and its application in rail transit has covered 53 projects.
The basic structure of a permanent magnet synchronous servo motor consists of a stator and a rotor.
The stator of a permanent magnet synchronous servo motor is similar to that of a traditional motor, but its number of slots is often different due to rigorous calculations.
Permanent magnet synchronous servo motors have a unique rotor structure, with permanent magnet poles mounted on the rotor.
Depending on the method of permanent magnet mounting, different rotor structures are classified as projectile-mounted, embedded (or surface-mounted, built-in), etc.