Research On Integrated Disturbance Suppression Strategy Of Permanent Magnet Synchronous Motor

With the advantages of high power density,simple structure,strong overload capacity and high power factor,permanent magnet synchronous motor(PMSM)is widely used in various fields such as industrial production,transportation and electric traction.With the development of the times,the performance requirements of PMSM in these industrial occasions are becoming higher and higher.PMSM is a nonlinear and multi-input system,and the disturbances to be changed along with the application situation are different,therefore traditional PID control method is difficult to meet the demand of high accuracy and high performance.Traditional active disturbance rejection control(ADRC)is a disturbance rejection control method that inherits the advantages of PID control and does not rely on the accurate model of the system,and the design method is simpler after linearization,but there are still two main problems restricting its development:(1)it is unable to suppress the periodic disturbance dominated by high-order harmonics in permanent magnet synchronous motor;(2)The disturbance observation has the problem of phase lag.Based on the idea of active disturbance rejection control and the in-depth study of the disturbance model mechanism of PMSM,in order to further improve the dynamic and steady-state performance,this paper proposes a comprehensive disturbance suppression strategy of current loop periodic disturbance observer based on resonant control and speed loop phase leading extended state observer.The specific contents of this paper are as follows:Firstly,the mathematical model of PMSM and double closed-loop vector control system are introduced.Various disturbances in PMSM are analyzed and classified according to periodicity and aperiodicity.Finally,the double closed-loop vector control model of PMSM with disturbance is obtained.Secondly,the design method of current loop periodic disturbance observer based on resonance control(RCB-PDOB)is proposed.Considering the periodic disturbances in the current loop of PMSM,such as dead time effect,a current loop periodic disturbance observer based on resonance control is proposed to suppress the specific harmonic disturbance in the current loop.Considering the resonance control characteristics and the robustness that should be possessed in the digital system,the engineering design structure of the periodic disturbance observer based on the classical disturbance observer(DOB)architecture and the frequency characteristic curves under different parameters are given,the transfer function of the disturbance measurement is deduced,and the flow-based parameter tuning design method is provided.Thirdly,the phase leading correction unit is introduced to improve the ADRC of speed loop.Firstly,the basic principle of ADRC is introduced.The reason for the disturbance observation lag of extended state observer(ESO)is deduced by frequency domain analysis.Aiming at this problem,the phase lead correction unit is introduced to improve it to obtain the phase leading extended state observer(PLESO).This paper gives its stability proof,noise sensitivity analysis,general parameter setting method and discretization implementation steps,and deploys it to the speed loop to improve the dynamic performance,which includes response speed to torque changes and speed tracking ability.Finally,the physical test platform of PMSM for verifying the proposed control strategy is introduced.The proposed current loop periodic disturbance observer and phase lead expansion state observer based on resonance control are deployed in the current loop and speed loop respectively.Taking PI control,traditional DOB control and ADRC as the control group,in the speed loop experiment,through the speed tracking test and load torque suppression test,it is verified that the proposed PLESO has faster response speed and shorter regulation time;in the current loop experiment,through the constant speed command tracking experiment,it is verified that the proposed RCB-PDOB can effectively reduce the current ripple and improve the steady-state performance of the current loop.