Design And Implementation On Permanent Magnet Synchronous Motor Servo System

The most attractive points of permanent magnet synchronous motors (PMSMs) are simple structure, high efficiency, high power density. In recent years, AC servo systems are now being extensively applied in industry where high precision, high speed, large torque or other characteristics are required, thanks to PMSMs. Based on this background, the simulation model of the PMSM servo system controlled by space vectorl control technology and fuzzy control strategy is analysised in this paper. In addition, effort on hardware and software design has been done to implement the PMSM servo system.Firstly, the mathmatical models of PMSM are presented and deeply analysised. And the theory of space vector pulse width modulation (SVPWM) has been studied with the undersanding of decoupling control. In order to improve system performance, a fuzzy logic PID controller capable of optimising parameters online is proposed in this paper. And research has been done on whether this controller is superior to tranditional PID controller on system performance.Secondly, hardware of this PMSM servo system has been designed and debugged. According to the distribution of system's functions, three PCBs were made, including system control circuit, angle detecting circuit, driving and protecting circuit. System control circuit use TMS320F2812 as digital signal processor. Analog device AD2S80A is applied to decouple the angle data from output signals of resolver in angle detecting circuit. And IR2136 is used to drive three phase inverter in driving and protecting circuit. The hardware system adopts currrent sensor and AD976A to get values of motor's phase currents. Moreover, Analog signals are handled by amplification, correction, system protection or other processing.Finally, software of this PMSM servo system has been programmed and debugged. With the introduction of TI's Code Composer Studio 2.2 (CCS2.2), features and programming skilles about the files contained in this software are discussed in this paper. Software tool, such as IQmath library, is proposed to port a floating-point algorithm into fixed point code on DSP2812. The software program includes main function, interrupt service routines, functions, and macros. And functionalities, flow charts, methods of programming and debugging of the software program are discussed. The results of the experiment shows that the PMSM runs steady and reliable, which means the design of the PMSM servo system is correct and appropriate.