Research On Sensorless Control And Chaos Control Of PMSM

PMSM has many advantages,such as high power density,high efficiency,low inertia,small size and energy saving.It has been widely used in new energy wind power generation,aerospace,shipbuilding industry and flexible manufacturing.At present,the common high-performance control methods of PMSM are vector control and direct torque control.However,the existence of sensors also brings many inconvenient restrictions.On the one hand,it increases the complexity of the system,leading to a substantial increase in manufacturing costs,on the other hand,it reduces the stability of the motor system in operation.The sensorless technology collects the rotor position information parameters through the control algorithm,and detects the rotor information of the motor accurately,avoiding the system misalignment caused by the sensor installation.At the same time,the complex nonlinear of PMSM mathematical model will lead to chaos phenomenon under certain parameters and working conditions,which is represented by the violent vibration of speed or torque,and the current noise will also be generated,which will directly affect the dynamic performance of the motor,and even lead to motor damage.Therefore,this paper studies the sensorless control technology and chaos control of PMSM.The main contents of this paper are as follows:(1)The mathematical model of PMSM is established,the principle of coordinate transformation is analyzed,the chaos model of PMSM is derived,and the basic theory of port controlled dissipation Hamiltonian system is analyzed and discussed.(2)This paper analyzes the basic principle of sliding mode control theory and the necessary conditions of sliding mode,describes several causes of chattering,and puts forward several widely used strategies to reduce chattering.Aiming at the chattering problem caused by the discontinuity of switch function and the phase delay problem caused by the use of filter,the traditional sliding mode observer is improved.The hyperbolic tangent function is selected as the switch function of the system.The position and speed of the rotor are estimated by the phase-locked loop,and the phase-locked loop is improved.(3)According to the port Controlled Hamiltonian system and its passive control scheme,the PCHD chaotic model of PMSM is established.Based on this model,an adaptive observer is established to observe the unknown parameters of PMSM and suppress the chaotic state of PMSM.(4)An adaptive sliding mode variable structure chaos controller is designed.In order to further improve the dynamic performance of the system and better suppress the chaos state of PMSM system,a hybrid control strategy of gain parameter switching sliding mode variable structure-dissipative Hamiltonian chaos is proposed based on the adaptive sliding mode observer,which can effectively control the chaos state of PMSM and further improve the stability and robustness of the system.Based on MATLAB simulation software,the above strategies are modeled and simulated,the traditional sliding mode observer simulation model is established,and the improved new observer is simulated and analyzed,which proves that the method can accurately observe the rotor speed and position information;the SMC-PCHD hybrid chaos controller is established,and the simulation results show that the chaos phenomenon of the system can be effectively suppressed.