Research On Sensorless Control Of Permanent Magnet Synchronous Motor At Full Speed

The excellence of Permanent magnet synchronous motor is good energy saving,high power density,stable current operation,simple structure,and sensitive dynamic response.They are widely used in wind turbines,various pumps,and new energy vehicles.In order to continuously obtain accurate and effective speed and rotor position information to achieve a closed loop,the use of mechanical sensors is a common method in engineering practice.This not only increases the cost of the components,the installation is relatively difficult,and the stability in the environment of extremely high low temperature,high acid and alkali,high corrosion,and high frequency vibration cannot be guaranteed.In order to solve the above problems,the position sensorless control system should appear,and it has become a research hotspot.In the dissertation,the permanent magnet synchronous motor is used as the controlled object,and the position sensorless control is researched on the basis of vector control.In order to solve the problem that the position sensorless control strategy of permanent magnet synchronous motor is heavy reliance on motor model parameters between the middle and high speed phases,the estimation accuracy of rotor state information is low in the start-up phase or the low-speed operation phase.The mathematical model of the motor is constructed and the coordinate system is converted,and the principle of SVPWM control is described in detail on the basis of vector control.A composite control strategy combining the rotating high-frequency voltage signal injection method and the model reference adaptive method is used to construct a position sensorless speed switching area algorithm,and the stability or excellent control of the permanent magnet synchronous motor in the full speed range is realized by the weighting method of the two.Through Matlab/Simulink simulation,dspace platform semi-physical simulation,MMC motor controller platform test,and dynamometer test platform verification,and dynamometer test platform verification.The method can realize smooth switching between low rotating speed and high,improve the dynamic stability of the control system,and has the advantages of strong dynamic adjustment ability and good robustness.