Research On Fast Parameter Tuning Method Of Load Simulator Based On Model Driven

Load simulator is a kind of hardware in the loop simulation equipment commonly used to simulate the aerodynamic load of missiles,aircraft and other aircraft in the flight process.It can test the load of aircraft in the laboratory.Its performance directly affects the accuracy of load simulation of test pieces.However,the performance of load simulator is closely related to the accurate setting of its own parameters（connection stiffness,inertia,control parameters,etc.）.Considering the coupling influence of multiple parameters,how to set it quickly and effectively has become an urgent problem to be solved.Under this background,from the perspective of time-domain and frequency-domain characteristics of load simulator,this topic studies the parameters that are difficult to be quickly adjusted,such as stiffness,inertia and control algorithm.The main work contents are as follows:（1）Consult the relevant literature on load simulator at home and abroad,and analyze the main reasons affecting the performance of electro-hydraulic load simulator.According to the working principle and structure of electro-hydraulic load simulator,the mathematical model of electro-hydraulic load simulator is established.The unknown parameters in the model are identified by particle swarm optimization algorithm,and the accuracy of model identification is verified.（2）According to the basic principle of frequency domain analysis,the influence of mechanical structure parameters such as connection stiffness and inertia on the frequency characteristics of electro-hydraulic load simulator is studied.According to the influence trend of different mechanical structure parameters on the frequency characteristics of electro-hydraulic load simulator,the optimization objective function is designed,and the rapid setting method of load simulator parameters is proposed to solve the problem that the frequency characteristic curve of steering gear is difficult to fit with the target frequency characteristic curve.The setting of the mechanical structure parameters of the electro-hydraulic load simulator is completed in the frequency domain.It is verified that the set mechanical structure can meet the requirements of the frequency characteristic index of the steering gear system and save the time required in the debugging process of the load simulator.（3）In terms of time domain,it mainly evaluates the accuracy of loading force.The accuracy of loading force is often evaluated by the percentage of surplus force elimination.In order to achieve a good effect of redundant force elimination,this paper theoretically analyzes the mechanism of redundant force,studies how to suppress redundant force from mechanical structure parameters and control algorithm,simulates the influence of different mechanical structure parameters on redundant force,and gives a reasonable range of mechanical structure parameters.The corresponding speed compensation + nonlinear PID algorithm is designed,and the effect of restraining redundant force under the control of speed compensation +nonlinear PID algorithm,speed compensation + PID algorithm and PID algorithm is compared.It is verified that speed compensation + nonlinear PID algorithm can restrain redundant force better under high frequency,and the parameter setting of control algorithm is completed.（4）The experimental platform of electro-hydraulic load simulator is built,and the overall scheme design of the experimental platform is introduced in detail.Based on the developed test-bed,the force loading experiment under sinusoidal,step and sweep signals is designed.Through the analysis of experimental data,the redundant force of the system is fully restrained under the response of sinusoidal signal;Under the step signal response,the system has faster response speed.The experimental results show that the adjusted mechanical structure and control algorithm parameters can effectively suppress the redundant force and improve the dynamic characteristics of the system.The rapid parameter setting method of load simulator can effectively set the mechanical structure parameters such as connection stiffness,inertia and control parameters,and shorten a lot of time in the design and commissioning stage of load simulator.The system after parameter setting has good dynamic characteristics,can effectively suppress the generation of excess force,meet the index of frequency characteristic curve of steering gear system,and provide a theoretical model and optimization method for the design and debugging of load simulator.