Research On Nonlinear Disturbance Modeling And Compensation Strategy For Motor-drive Servo System

The motor-drive servo systems have important applications in aviation,military,communication and so on.It is an important part of radio telescope,radar and test turntable.The production process and control strategy play important part in the performance of the implied equipment.The wind disturbance,backlash,motor torque fluctuation and friction are all nonlinear disturbance factors of the servo system.The friction has an obvious effect on performance of the motor-drive servo system in low-speed work state.It may lead to creep,shaking and worsen the tracking stability of the whole system.Therefore,it is necessary to analyze the friction factors and build the systematic and accurate mathematical model.It is very meaningful to reduce the tracking error of the servo system though the research of friction.The work of this paper is listed as below.Firstly,the developing situation of servo system is introduced,and the current researches of friction are also analyzed.The dynamic and static characteristics of friction are explained.On the basis of the existing friction models,the LuGre friction model is introduced in our research.Secondly,the motion characteristics of the servo system are analyzed.A linear model of single input single output(SISO)servo system is proposed.According to the motor drive servo system established in this paper,the system parameter identification experiment and friction identification experiment are designed and implemented.Finally,based on the traditional PD controller and the fixed compensation strategy based on LuGre model,simulation analysis is undertaken.The simulation results show that the compensation strategy based on LuGre friction model has better compensation effect than the traditional PD compensation strategy.