Research On Sensorless Control Technology And Direct Torque Control Technology Of PMSM

Permanent Magnet Synchronous Motor(PMSM) have been applied widely in electric vehicle, railway and urban rail transit, new energy development and utilization and other fields, for merits such as high power density, high power factor, high efficiency, small rotor fever, Strong overload capacity. PMSM will be more widely applied.Direct Torque Control(DTC) technology has a simple structure, fast torque response and good robustness. And when the motor starting, the precision requirements for the rotor initial position angle is lower. The together of sensorless control technology and direct torque control technology can effectively make up for some shortcomings, Such as estimation error is large at low speed and it is difficult to start motor.Firstly, this paper deduces the model of traditional and based on PI controller PMSM DTC. The corresponding matlab simulation models are established. The simulation results show that based on PI controller PMSM DTC can reduce the torque and flux ripple of traditional PMSM DTC. The control performance of PMSM is improved.And then, the mathematical model of traditional PMSM Sliding Mode Observer(SMO) was deduced. Based on the mathematical model of the traditional PMSM SMO, the mathematical model of the modified PMSM SMO is established. The modified PMSM SMO weakens jitter problem in the traditional SMO, reduces the impact of the system interference, enhances the robustness of the system and improves the control performance of the system. The simulation results show that the feasibility and effectiveness of based on the modified sliding mode observer of the PMSM sensorless control technology.At last, a two-stage matrix converter experimental platform based on DSP28335and FPGA was built in this paper. The experiment of based on PI controller PMSM DTC and based on modified PMSM SMO sensorless control were completed. The experimental results show that the feasibility and effectiveness of based on the modified sliding mode observer of the PMSM sensorless control technology.