Research On Adaptive Backstepping Control System Of Permanent Magnet Synchronous Motor

With the rapid development of science and technologyy, permanent magnetsynchronous motor (PMSM) is widely used in the field of CNC, aerospace and electriclocomotive because of the advantages of small size, high power factor and high efficiency.The paper focuses on how to improve the response speed and robustness of PMSM speedcontrol system, and the following main contents are researched.Firstly, the paper reviews current development of PMSM speed control system andthe modern control theory, and describes several common methods and working principleof PMSM control by making research of a large number of related references.Secondly, based on the structural characteristics and working principle of PMSM, thepaper establishes a mathematical model of PMSM in three different coordinate systemswith method of coordinate transformation and analyzes many factors which could affectthe motor’s speed to make convenient for designing speed control system.Thirdly, focus on how to decrease the effect of the nonlinear and strong couplingcharacteristics of PMSM, this paper designs a dynamic inverse backstepping control speedcontroller and adaptive backstepping control of speed controller to weaken the loaddisturbance and time-varying parameters influence on speed. The dynamic inversebackstepping controller can decouple the relationship between stator current and speed inorder to ensure the stability of the control system by using the backstepping control. Onthis basis, fuzzy parameters approximator has the ability to eliminate the influence of loadtorque, viscous friction coefficient and the stator resistance on system stability. The speedcontroller of adaptive backstepping is based on the vector control strategy of id=0toincrease the speed response. The adaptive law of stator resistance and load torque canimprove the response speed and robustness of the control system further.At last, this paper analysis the results of the simulation of two kinds of controllerswhich treats surface mounted PMSM as the controlled object on the MATLAB simulationplatform through the M-file. Comparing with adaptive backsetpping controller, dynamicinverse backstepping controller can weaken the influence of load disturbance, resistance and viscous friction coefficient. However, the adaptive backstepping controller onlyreduces the influence of load disturbance and resistance on PMSM speed, but both of themhave a good ability of response speed and robustness.