Research On Sensorless Control System Of Permanent Magnet Synchronous Motor

In recent years,with the development of power electronics technology and rare earth materials technology,the permanent magnet synchronous machines(PMSMs)has been widely used,and the control technology of the PMSM without position sensor is regarded as the current research hot issues.The technology can effectively reduce system costs,reduce system size and increase the power density.In this paper,sensorless control of PMSMs was studied.The purpose is to achieve that sensorless control of PMSM operates at full speed.In this paper,the structural characteristics,the mathematical model and the speed regulation method of PMSM were firstly analyzed,and i_d=0 of the vector control system and its Simulink model were established.Tthe simulation analysis was carried out.Then,for low-speed sensorless control technology,the high-frequency pulsed voltage injection method for surface-mount synchronous machine(SPMSM)was emphatically deduced and analyzed.Aiming at the signal amplitude attenuation caused by the band-pass filter in the traditional method,through the theoretical study and the improvement of signal processing,the attenuation of signal was reduced.The traditional method and the improved method were simulated and analyzed.The results show that the two can realize the sensorless control at low speed,which was in line with the theoretical analysis.What's more,the position sensorless control technology of model reference adaptive algorithm suitable for medium and high speed was analyzed and inverted.Based on thei_d=0vector control used in this system,a simplified algorithm was presented.According to the Popov's super stability theory,it is proved that the simplified system is asymptotically stable.The simulation analysis of the two methods had been carried out to verify the feasibility of the algorithm.And the research of sensorless control strategy in full speed range was carried out.The high-frequency pulse voltage injection method and simplified model reference adaptive algorithm were combined together,and the simulation results were in line with expectations.Finally,the system experiment platform was designed,and the hardware and software of the system were designed,and the experiment platform was debugged.The experimental results verify the efficiency and feasibility of the proposed control strategy.