Research On Control Strategy Of Permanent Magnet Synchronous Motor Based On LADRC And DPCC

Because of its advantages of small size,high power factor and power density,large starting torque and strong overload capacity,permanent magnet synchronous motors(PMSM)have received extremely extensive attention in the fields of small and medium power,high precision,wide speed range servo control systems and high performance professional drives.With the development of industrial technology,traditional motor speed regulation strategy has gradually failed to meet the increasing demand for speed control system control performance in various industries.Therefore,it is of great academic research value and practical application significance to design a control technology with high control accuracy and high robustness for PMSM speed control system.In this thesis,active disturbance rejection control(ADRC)technology is used to design the linear ADRC controller of speed loop of PMSM double closed loop control system.Firstly,the basic principle and characteristics of ADRC technology are introduced.Based on this,linear active disturbance rejection control(LADRC)technology with simpler structure and greatly simplified parameter tuning is introduced.Then,the LADRC controller is designed based on mathematical model of PMSM in synchronous rotating coordinate system.Although the introduction of tracking differentiator guarantees the speed of the system’s speed tracking and achieves no overshoot,it also causes the system to reduce tracking performance of time-varying reference with high frequency of change.Therefore,based on the analysis of the reasons for the decline in tracking performance,the improved LADRC controller was designed and simulated.It can be seen from the simulation that the improved controller increases speed tracking performance of the system,but there is still room for improvement in current control capability when there is load disturbance in the system.In order to improve dynamic response ability of the speed control system,the current loop deadbeat predictive current controller(DPCC)of PMSM dual closed-loop control system is designed in combination with current predictive control technology.First,after introducing the principle of traditional DPCC technology and analyzing the influence of sampling delay on the control performance of discrete control systems,the DPCC algorithm considering sampling delay is introduced.Combined with the mathematical model of PMSM,the DPCC controller for current loop is designed.After that,the influence of motor parameter changes on the system is analyzed,and combined with the advantages of extended state observer in ADRC technology in terms of antiparameter disturbance,the improved DPCC controller is proposed and simulated.Then,combined with the designed LADRC controller based on differential compensation of speed loop and the DPCC controller based on linear expanded state observer of current loop,the PMSM double closed-loop control system is designed and its static and dynamic characteristics are simulated and analyzed.Finally,an experimental platform for PMSM was built based on DSP and IPM,and the static and dynamic characteristics of the designed PMSM control system was experimentally analyzed on the experimental platform.It can be seen from the experimental results that the control system has the characteristics of fast speed tracking,no overshoot during speed regulation,good current control effect,strong parameter robustness,and excellent load disturbance resistance.The paper has 51 pictures,2 tables,and 83 references.