Research On Electro-hydraulic Servo Loading System

With the development of national defense industry, the electro-hydraulic servo loading system, as the most important part of the half hardware-in-loop simulation equipment, plays a great role in the study of loading experiment of aircraft rudder. Therefore, the research of electro-hydraulic servo loading system is a hot research topic at present. Restraining the influence of redundant force and designing the loading cotroller are the key technologies of the electro-hydraulic servo loading system. Then the performance of the electro-hydraulic servo loading system can be promoted through the research.Firstly, the model of the electro-hydraulic servo loading system is built on the AMESim platform. Then the simulation is studied based on the model. Secondly, variety control strategies are applied to solve the problems of serious overshoot and high frequency oscillation of the electro-hydraulic servo loading system. Based on the structure invariance principle, the partial error is eliminated through adding structure compensation unit. Due to the characteristics “ADRC do not depend on the mathematic model of controlled object. And the integrated disturbance can be observed by the Extended-State-Observer. As a result, the dynamic error can be compensated”, ADRC is applied. Then the system overshoot is avoided by Tracking-Differentiator method. And the problem of high frequency oscillation is solved by Extended-State-Observer method. So the stability and robustness of the system are improved obviously, and the accuracy requirements are met. Then, the electro-hydraulic servo loading controller is designed including hardware design, PCB design, and software design. The hardware modules are consist of the minimum system of DSP, the module of AD, the module of signal acquisition and conditioning, the module of DA, the module of servo drive, the protective circuit, the power circuit, and so on. Finally, because of the limitation of the experimental conditions, the systematic test is made based on the loading controller with partial control strategy. The results show that the influence of the redundant force to the electro-hydraulic servo loading system is restrained effectively and the loading accuracy meet the requirement. In addition, the performance requirements of the controller are satisfied and the control effect is achieved.Through the research of the control strategy to the electro-hydraulic servo loading control system, the new way of eliminating and restraining the influence of redundant force is proposed. Through the research of the electro-hydraulic servo loading controller, the new method of the development of electro-hydraulic load simulator is provided.