Research On Mathematical Mode And Dynamic Characteristics Of Electro-hydraulic Load Simulator

The electro-hydraulic load simulator is half-objective experimental equipment simulating the air power torque exerted on the rudder of flight object when flying in space. Its function is to simulate, under laboratory conditions, different kinds of air power torques exerted on the rudder so as to detect technical function index of the rudder driving system. Thus the classical self-destructing all-objective experiment will be converted to forecasting half-objective experiment in laboratory to achieve the aims such as shortening lead time, saving developing funds, enhancing reliability and success proportion. Along with the development of national defense and military industry, not only the demand for electro-hydraulic load simulator is urgent but also higher and higher control performances and technical index are requested, so it is urgent affair to develop electro-hydraulic load simulator with high accuracy. Because electro-hydraulic load simulator is a typical passive loading system and has many unique characteristics, the research on some theoretic problems, especially the surplus torque, has not got matured. Just according to above practical and academic demands, this dissertation carries out the study.This dissertation analyzes the basic operational principle and basic construction of electro-hydraulic load simulator, and clarifies the main technical problems and technical estimating index. Based on summarizing a large number of documents inside and outside our country, the current situation of research on electro-hydraulic load simulator, especially the study achievement of the surplus torque, are analyzed and then the study tasks of this dissertation are confirmed.In this dissertation the author builds up mathematical model of eletro-hydraulic load simulator and simplified it, and then takes deeply theoretical analyses on the control performances as well as their relations with structure parameters to provide the theoretical foundation of improving control performances of electro-hydraulic load simulator. Starting from dynamic and static characteristics of actuator, the dissertation reveals the generating mechanism of surplus torque and its substance quality. The influence factors to surplus torqueand its effects on control performances of loading system are proceeded to analyze in order to find out the best way to overcome surplus torque and enhance the control performances.The control methods adopted in this dissertation to enhance control performances of electro-hydraulic load simulator are also applicable to other passive loading systems.