Development Of Three-motor Synchronous Control Platform Based On Active Disturbance Rejection Controller

With the improvement of living standards,the people’s growing material and cultural needs directly stimulate the development of automation control technology.Synchronous control of multi-motor system also requires higher accuracy, rapidity and stability.In this paper, the decoupling control of speed and tension of the three-motor synchronous system are studied. At the same time, according to the hardware of the control system structure, the corresponding control platform is designed.The three motor system is a high order,nonlinear and strong coupling system, in which high performance of synchronous control is required. In this paper,the auto disturbance rejection control technique is introduced and analyzed in detail and a new controller for the speed and tension of the motor is designed. As a result, the decoupling between the two parameters is realized by auto disturbance rejection technique. After analyzing the system model of the control system and the coupling relationship between speed and tension, the control scheme of the master-slave control is adopted in this paper. The active disturbance rejection controller is introduced after analyzing the advantages and shortages of the PID controller, in which various uncertain factors,such as coupling and disturbance,are estimated and compensated by using ESO(Extended State Observer),meanwhile the estimation and compensation is fed back to the front of the controller.In order to reduce the cycle of the control of process control,in this paper,a combined multi-core control platform based on MCU, DSP and CPLD is designed.The cycle of the control of process control is limitd in 10 ms and a better control of the multi motor system mentioned in this paper has been realized with each processor working together. The function of MCU in the control platform is to collect the two tension values of the digital to analog conversion,and transfer the two tension value to CPLD. The function of CPLD is to count the photoelectric encoder to measure the speed of the motor, and feedback the measured speed value to DSP.CPLD has the function of filtering the output of the photoelectric encoder,receiving tension parameters sent from MCU,feedbacking speed and tension parameters to DSP,communicating with three inverters, receiving control command from DSP. At the same time, the PC(Personal Computer) interface to display the real-time parameter values, to observe the effect of experiment is designed in the paper and using the Excel table in the permanent preservation of the experimental data in PC is also developed.The control platform designed in this paper had run in the multi-motor system mentioned in this paper. After comparing the decoupling and load experiment of the PID control scheme with the auto-disturbance rejection control scheme, that the decoupling ability and the anti disturbance ability of the auto-disturbance rejection scheme is better than that of the PID control is proved. Conducting a comparison between the platform with PLC S7-300 and the platform this paper designed both based on ADRC, the results show that the control performance of the platform is better than PLC. So this platform has good prospects for development and industrial demand.