Research On Fully Digital Ac Servo System Based On DSP

With the the development of permanent magnet materials, power electronics technology and digital signal processors, AC servo system of permanent magnet synchronous motor (PMSM) obtain a wide range of applications. The excitation of permanent magnet synchronous motor's rotor is generated by the permanent magnets, PMSM has non-excited winding and slip rings, brush, has the advantages of high efficiency, high power density, a small moment of inertiaand and high reliability.In this paper, on the base of research of PMSM's mathematical models and control theory , full-digital AC servo control system is designed and developed based on TI's high-performance DSP—TMS320F2812.The hardware of the control system is mainly constituted by the digital signal processing chip (DSP) and intelligent power module (IPM). In the current sampling circuit design, in order to overcome the the temperature drift problem of A / D converter, current sensor chip IR2175 is used, and DSP's high-speed of data processing capabilities is used to achieve the motor phase current detection.In the software the control algorithm using id = 0 space vector pulse width modulation(SVPWM), a typical three-loop control system is used in the servo system,it contains the position loop, velocity loop and current loop, this three loops all use the programming method to achieve the digital in the DSP . Feedforward controller is used in the position loop and PI controller is used in the speed loop and current loop. Digtal gear and the software algorithms of dealing with optical encoder and current sensor signals are also designed. In addition, the paper also completed the development of computer monitoring software based on LabVIEW, and it monitors the motor running through the serial port.In the Matlab / Simulin environment the control model of servo system was established, and complete the simulation to verify the feasibility of the control algorithm, and preliminary get the parameters of the loop controller in order to facilitate the selection of parameters of the actual debugging. The experimental research is complete and the results show that the servo system has high stability and low cost.At last, the research and development work are summarized and further studies are prospected.