Research On Sensorless Control System Of Permanent Magnet Synchronous Motor For Electric Vehicle

Because the interior permanent magnet synchronous motor has the advantages of high power factor,high efficiency,and stable current,it is widely used in the field of electric vehicles.In the process of using a traditional motor,the acquisition of its speed and position information often requires the help of mechanical position sensors,but its installation in the motor system will cause many problems.The proposal of position sensorless technology undoubtedly solves this problem well.First,the current domestic and foreign research achievements in position sensorless technology are introduced in detail,and based on the comparison of existing different types of vehicle motors under various performances,permanent magnet synchronous motors are selected as the research object of this article.Secondly,according to the design principle of the motor controller algorithm,step by step,through simplification,a mathematical model suitable for the selected motor control system is obtained,and an in-depth study is carried out on the analysis of vector control technology,and a suitable control is selected through comparison ways.Finally,the principle analysis and simulation research on the algorithm of the position sensorless technology are carried out,and the verification is carried out on the d SPACE platform.Because the position sensorless control technology of permanent magnet synchronous motor has additional loss and position estimation delay in the zero-low-speed stage,and has a relatively large dependence on model parameters in the medium-high-speed stage.For this reason,on the basis of the high-frequency signal injection method,the pulsed high-frequency voltage signal injection method based on the position tracking observer is used as the algorithm of the motor controller in this paper.By combining the model reference adaptive method and the improved high-frequency signal injection method,a position sensorless compound control method for the full speed range is proposed.How to select the speed switching interval and adopt the appropriate switching algorithm has become the key to the compound control method.By using a weighting algorithm to calculate the speed and position of the switching interval,the problem of speed and position jumps in the two algorithms during the transition is effectively solved.And based on the analysis of the various position sensorless algorithm principles proposed in this paper,a simulation model is built on the Matlab/Simulink platform,and the simulation graphics obtained are compared and analyzed.The results show that the compound control method adopted in this paper can be The motor speed and rotor position information are detected quickly and accurately,and smooth switching between zero and low speed and medium and high speed is realized,so that the dynamic response performance of the system is improved,and the speed of dynamic adjustment is accelerated,and the robustness is also enhanced.