Research On High Response Control And Vibration Suppression Strategy Of Permanent Magnet Synchronous Servo Drive System

Permanent magnet synchronous servo motor(PMSM)is widely used in industrial automation system because of its high efficiency,high precision,and high power density.However,with the increasing requirements of production quality and efficiency in industrial field,the response performance and control accuracy of PMSM system need to be improved.For this reason,combined with the National Natural Science Foundation project,the key technologies of PMSM system such as high response control and vibration suppression are deeply studied to achieve the goal of high-speed and high-precision control.The specific contents and innovations are as follows.Aiming at the problem that the response bandwidth of the current loop limits the dynamic response of the system,the limiting factors of the theoretical bandwidth of the current loop are analyzed based on the mathematical model of current loop.And the relationship between the theoretical bandwidth of current loop and parameters such as Pulse Width Modulation(PWM)delay time and current filtering time constant is studied.To reduce the equivalent control delay of current loop,the hardware current loop bandwidth expansion strategy based on Field Programmable Gate Array(FPGA)and Multiple Sampling Multiple Update(MSMU)method is designed.The decoupling control strategy of vector control current loop is studied to further improve the dynamic response performance and control accuracy of current loop.Compared with the traditional software current loop control,the current loop bandwidth of servo drive system can be increased more than two times.To achieve fast response and small error tracking to the position control command,an adaptive feedforward control based on state observer is introduced for speed and current command.Compared with Kalman filter method,a serial second-order speed and acceleration observer method based on extended state observer is proposed,which can obtain lower delay and higher accuracy speed and acceleration estimation.At the same time,an adaptive torque feedforward control method based on recursive least square method is proposed,which can identify the model parameters in real time and achieve more accurate feedforward control torque,further achieve high response tracking even when the control object parameters are unknown or changing.The vibration suppression technology of servo drive system based on frequency characteristics is proposed,which can effectively suppress system vibration at high speed.The key resonant frequency characteristics of the controlled object are identified by using the non-parametric frequency characteristics identification method.Aiming at the problem of unknown or drifting vibration frequency,an adaptive notch filter method based on frequency tracking strategy is proposed,which can track the vibration frequency in real time and realize the dynamic adjustment of notch filter parameters.Finally,the input shaping vibration suppression strategy is studied,and an improved negative pulse input shaping method is designed,which reduces the instruction delay and further improves the dynamic performance of the system.Combined with the servo drive designed by the research group,the experimental platform of PMSM servo system is built.The high response current loop control,adaptive feedforward control and vibration suppression technology are verified and analyzed.The developed servo drives are applied to the industrial high precision engraving and milling machine and industrial robots,and the experimental results show the effectiveness of the control strategies.