Research On Vector Control Of Sensorless Permanent Magnet Synchronous Motor Based On Double Sliding Observe

With the continuous development of society,permanent magnet synchronous motors are used in aerospace,rapidly developing new energy vehicles and other industries due to their simple structure,high power factor,wide speed range,fast dynamic response,and strong reliability.More and more widespread.The existing traditional permanent magnet synchronous motor control methods,commonly used incremental encoders and other mechanical sensors,not only increase the cost and system volume,but also worry about stability in some relatively harsh environments,and the later maintenance and repairs are cumbersome.It can be seen that the research on sensorless control methods of permanent magnet synchronous motors has a certain significance and is valued by scholars at home and abroad.Firstly,the mathematical model of permanent magnet synchronous motor is established through coordinate transformation and vector control theory.At the same time,it analyzes the space vector pulse width modulation technology that can provide stable and efficient inverter effects in the motor control process.Based on the in-depth study of theoretical knowledge,the system model is built on the commonly used simulation software MATLAB/SIMULINK,and the simulation analysis is performed.Next,the high-speed and low-speed operating conditions are studied separately.In the high-speed operation stage,in order to solve the problems of poor robustness,large error and slow response in the control process of the traditional sliding mode observer in the middle and high speed stage,a method based on the dual sliding mode observer is proposed.This method is different from the traditional sliding mode observer method.It uses sliding mode speed control instead of traditional PI adjustment to reduce the sensitivity of the control process to parameter changes and improve the speed of operation response;in the flux linkage observer part,with the help of an adaptive filter Filter out the harmonics generated in the detection process to make the results more accurate;in addition to phase locking and phasing,the quadrature phase-locked loop introduces rotational speed to improve response speed.When the motor is running at low speed,the back EMF of the surface mount permanent magnet synchronous motor is not easy to be detected because the back EMF is too small during the low speed operation stage,which leads to the excessive error of the sliding mode observer method,and the double sliding mode observer method cannot Be applicable.The pulsation high-frequency injection method is completely different from the sliding mode observer method when the motor is running at low speed,and the performance is more accurate and stable.Secondly,the methods mentioned above are only applicable to a specific speed range.When the specified speed range is exceeded,the robustness will be poor and the error will be too large.At present,there is no single motor control method that accurately calculates the motor speed and rotor position in the full speed range.The compound control strategy refers to the combination of the two methods,combining the advantages of the two control methods,and setting an optimal speed range as the transition zone,so that the two methods can be switched smoothly to estimate the rotor when the motor is running at full speed Information.Finally,through more in-depth study and research on the simulation model,a hardware experiment platform is built on its basis.The core part is the DSP28335 main control chip.Through the analysis of three related modules,the software design and hardware operation of the permanent magnet synchronous motor are introduced.