Study On Direct Torque Control System For Permanent Magnet Synchronous Motor Basedon TMS320F2812

Along with the fast development of the motor production technology, power electronics and microelectronics, servo control system has been used in the field of industrial control and household appliances widely, and AC servo control system has become a development trend of servo control system. Therefore, to study the full-digital permanent magnetic synchronous AC servo control system whose executive motor is permanent magnetic synchronous motor, core component is DSP, and control strategy is direct torque control has an particularly important practical significance.Some research and amelioration on direct torque control system of permanent magnet synchronous motor has been done in this paper. Direct Torque Control (DTC) is a novel technology of frequency conversion after the vector control in the field of AC drive systems. Conventional DTC has some advantages, such as easy implementation, fast response and less effect of motor parameters'change, so a better dynamic performance can be obtained, but some large ripples of torque also exist. Aiming at the shortcomings of conventional DTC, a novel direct torque control system based on space-voltage vector pulse width modulation (SVPWM) is proposed in this paper. The SVPWM can help the inverter to realize continuous voltage vector modulation, decrease the current harmonic component, and restrain the torque ripples, and the DC bus voltage utilization can be improved and the speed range of the system can be expanded; meanwhile, fuzzy PI technology is applied in the speed controller to improve the response characteristic of the system .Based on the theoretical analysis of 3-phase permanent magnetic sinusoidal motor (PMSM), a mathematical model of PMSM and the simulation model of permanent synchronous motor system based on DTC have been built; furthermore, a lot of simulation researches have been done based on these models. To design the control system, the digital signal processor TMS320F2812 produced in TI Company is used as kernel control chip, and plentiful experimental tests have been done. The simulation and the experiment results show that the permanent magnet synchronous motor system designed in this paper not only can preserve the fast response performance of DTC, but also it can decrease the ripples of torque effectively.