The Research Of PMSM Control System Based On DSP

Servo control technology is one of most important components of the mechatronics, which is widely used in CNC machine tools, industrial robots, aerospace vehicles, electric vehicles, household appliances and other industrial products. Modern industrial production has proposed more and more demands for servo equipment and its performance. Therefore, it has a very important practical significance to develop the AC servo system with high performance and reliability.With the development of a new permanent magnet materials and improvement of permanent magnet synchronous motor's manufacturing, the servo system using permanent magnet synchronous motor as control object has attracted more and more attention.In the demand of high-precision, high-dynamic performance and small size, AC permanent magnet synchronous motor (PMSM) servo system has obvious advantages. PMSM itself does not require excitation current and does not need damper windings when the inverter supplies power. In addition, it has higher efficiency, power factors and smaller volume compared with the same capacity of PMSM. So the research on permanent magnet servo control system is becoming an inevitable trend and current focus.More and more AC servo systems use a digital signal processor (DSP) and Intelligent Power Module (IPM), which can complete the changes from analog control to digital control. And make AC servo systems turn to the development of digital, intelligence and network.This paper deeply studies the structure and characteristics of permanent magnet synchronous motor and establishes PMSM mathematical model in the corresponding reference frame according to the relations of three coordinate transformations. We detail and deduce theory of voltage space vector PWM technology (SVPWM) and give the software performance method based on DSP. PID control used widely now is improved combined with intelligent algorithm on the basis of the conventional PID control to achieve higher accuracy and better dynamic performance. In addition, the paper also explains the circuit in servo system, such as the current detection, intelligent power module, the module of under voltage and overvoltage protection, rotor speed testing and so on. The paper also studies why permanent magnet synchronous motor cannot automatic start on lack of starting torque and at last gives MATLAB simulation results.