Fractional Order Modeling And Control Of Pneumatic Variable Load Loading System

Pneumatic loading technology is one of the commonly used technical means in daily life.However,due to the compressibility,complex flow state and easily be affected by temperature of gas,as well as nonlinearity and time delay of pneumatic loading equipment,it is difficult to realize the accurate modeling and control of pneumatic loading system.In this paper,in order to improve the modeling and control precision of a set of pneumatic variable load power loading system,the fractional order model and fractional order controller are used to control the system.The specific research contents and results are as follows:The pneumatic loading system is affected by many uncertain factors,and it is difficult to obtain an accurate model only by mathematical modeling.This paper presents a fractional order identification modeling algorithm based on the improved gravity search algorithm,which has the advantages of high modeling accuracy and fast modeling speed.Using this algorithm,the pneumatic force loading part of the pneumatic friction and wear testing machine is modeled,and the fractional order model of pneumatic loading system is obtained.The fractional order PID controller changes the integer order of the differential and integral of the integer order PID controller into non-integer order,which enhances the flexibility of the controller and is more suitable for the control of nonlinear systems.The design process of fractional PID controller digital controller is simplified,and the improved gravity search algorithm is used to optimize the parameters of the controller,the precision of the parameters is improved.The simulation and experiment are compared with the integer order PID control effect,and it is proved that the fractional order PID controller can effectively enhance the dynamic performance of the tracking signal and improve the control accuracy.Because the device is easily affected by complex interference signals in the actual loading process.In order to enhance the anti-interference ability of the controller,a fractional order PID improved active disturbance rejection controller is proposed,the function of controller parameters is analyzed,and the key parameters are optimized.The interference signals are added in the simulation and experiment of the aerodynamic loading process.By comparing the tracking results with other controllers,it is proved that the fractional order PID improved active disturbance rejection controller has the advantages of strong anti-interference ability and strong robustness.