Research On Active Disturbance Rejection Control Of Electric Actuator Based On Identification Of Moment Of Inertia

As the main equipment for controlling valves,electric actuators have a wide variety of types and play an important role in industrial production.As the execution unit of the actuator,the accuracy of the motor model directly affects the control performance.The expanded state observer in the active disturbance rejection controller can deal with this problem well.It takes all disturbances generated inside and outside the system as total disturbances for estimation and compensation,without the need for an accurate model of the controlled object.Therefore,this paper studies the auto disturbance rejection control based on asynchronous motor,including the following parts:First of all,the models required for the corresponding simulation analysis are established for the various parts of the electric actuator transmission system and the valve characteristics.According to the theory of active disturbance rejection control,the speed controller of the speed loop is designed.In view of the large number of calculations brought by the tracking differentiator,the extended state observer and the nonlinear state error feedback,as well as a large number of adjustment parameters.The controller structure is simplified according to the actual application.The control system model is built in the simulation software,and the simulation experiment verifies that its control performance is better than the PI controller under no-load,loaded and speed control conditions.In view of the fact that the system moment of inertia is unstable due to different loads during actual operation or load disturbances,etc.,the least square method with forgetting factor and Landau discrete recursive algorithm are used to identify them in real time,and the two are compared and analyzed.For the performance of the method,a more appropriate Landau discrete algorithm is selected to identify the moment of inertia of the system.Aiming at the problem that the selection of gain coefficient in Landau algorithm is difficult to balance identification speed and anti-interference,it is improved by using different gain coefficients under different identification result errors.The identification result is transmitted to the compensation link of the active disturbance rejection controller to realize the self-tuning of the feedback gain,and the start-up on load and the anti-interference ability have been enhanced.Finally,based on the MC56F8255 chip,the software code and hardware circuit of the control system are designed,and the motor experiment platform is built.The experiment verifies the effectiveness of the auto disturbance rejection control method.