| Electromechanical actuator is a high-precision actuator.It is widely used in military,bionic robot,aircraft and aviation because of its small size,large torque,strong stability and flexible deployment.Electromechanical actuator control systems have the characteristics of non-linear,fast time-varying and multi-variable.Generally,they can only be described by rough mathematical models under ideal conditions.In addition,there are unknown load disturbances,unknown friction disturbances,and model errors in the control system of electromechanical actuators,which will challenge the precise control of electromechanical actuators.In practical scenarios,it is often not easy to obtain model information of electromechanical actuators,which may also cause control systems that rely on model information to fail or reduce performance.Based on the problems existing in the control of electromechanical actuators,this paper studies the angle tracking control system of electromechanical actuators.The main contents are as follows:First,this paper designs and sets up an experimental platform for electromechanical actuator control.Based on the experimental platform,a dynamic model for electromechanical actuators with uncertain disturbances is established.The discrete dynamic model of the electromechanical actuator control system is derived using Euler discretization The characteristics of the discrete dynamic model are analyzed,which lays a foundation for control system design and simulation experiments.Secondly,in response to the problems of unknown load disturbance,unknown friction disturbance and model error of the electromechanical actuator,this paper designs an active disturbance rejection control system based on phase nonlinear extended state observer.Estimating the total disturbance has a better estimation effect than the traditional extended state observer.Subsequently,the stability of the closed-loop control system was proved,and the effectiveness of the control system was proved through simulation and experiments.Last,in view of the shortcomings of the ADRC system based on phase nonlinear extended state observer,which cannot be applied when the parameters of the electromechanical actuator dynamic model are unknown,an active disturbance data-driven control system based on parameter estimation is designed.The control system does not refer to model information at all,and uses projection algorithms to estimate unknown model information.The control system can compensate the total disturbance in real time when the model information is unknown,and achieve high-precision angle tracking control of electromechanical actuators.It solves the problem of the dependence of the active disturbance rejection control system based on the phase nonlinear expansion state observer on the model information.More meaningful in actual production.Subsequently,the bounds of the estimated parameter error and the stability of the closed-loop control system are proved.The effectiveness of the control system is proved by simulation and experiments. |
