Nonlinear Analysis And Loading Performance Optimization Of Electric Linear Load Simulato

The vector control of the rocket engine is mainly realized by the steering gear pushing the fuel valve.As a high-precision servo position system,the steering gear directly affects the overall performance of military products.In order to ensure the performance and reliability of the servo drive of the steering gear,it is necessary to add a dynamic test link in the manufacturing process.Generally,a load simulator is used to perform load testing on the test bench,and the load performance of the load simulator directly determines the data validity and accuracy of the test item being tested.Therefore,how to improve the performance indicators such as the loading bandwidth,output force accuracy and robustness of the electric linear load simulator is worthy of research.This paper firstly models the mechanism of the loading system based on the structural characteristics of the physical components.A coupling control model including the loading subsystem and the steering gear subsystem is established,and the actual non-linear friction and clearance links are introduced.Aiming at the non-linear friction links in the system,the paper introduces the GMS friction model based on the established mechanism model,and verifies the effectiveness of the identification model through offline identification of the unknown parameters of the model and feedforward compensation simulation analysis;The gap link is measured through experiments and the DOB observer is used for simulation compensation analysis.Aiming at the excess force problem caused by the position disturbance of the steering gear subsystem,the paper focuses on the analysis of the reason for the excess force,and then carries out targeted control compensation,and designs a PID-based steering gear position feedforward controller and an adaptive GMS friction model.Backstepping controller,simulation results show that the improved controller is better than PID control.Completed the labview code compilation of PID feedforward compensation control strategy,performance parameter collection and analysis,and graphical display function on the test bench;on this basis,ELLS static and dynamic loading tests were carried out,and the test results were compared with traditional PID controllers.Analyzing the servo performance of the designed controller,the results show that the static and dynamic force output amplitude attenuation and phase lag error items are all within 10%,which satisfies the requirements of the actual simulation loading test.