Research Of Control Strategy Of A New Type Of Electro-hydraulic Actuator Based On Servo Direct Drive

With the development of science and technology, people's increasing demand for energy saving. The hydraulic system, while having the outstanding power-weight ratio advantage, but the use of most conventional systems at work the throttle characteristic, resulting in energy loss, low efficiency. These shortcomings greatly limit the application and popularization of traditional hudraulic systems.The new electro-hydraulic actuator is a new type of actuator. In this actuator, the quantitative pump is directly drived by servo-motor; through controlling the speed of servo-motor can change the output flow of pump, therefore achieving the speed or position control of hydraulic cylinder. This new type of electro-hydraulic actuator is essentially the volume speed control, which overcomes some of the shortcomings of traditional systems, with a strong anti-pollution, energy saving, low cost, high reliability, easy installation and connection and other notable features.This thesis takes a new type of direct drive electro-hydraulic servo actuator as the research object. Based on the use of AMESim and MATLAB / Simulink for co-simulation, and draw some useful conclusions are based on the MATLAB RTW xPC real-time control technology, built the platform which based on the new direct drive electro-hydraulic servo actuator displacement control experimental, realized the general PID control and fuzzy control. Simulation and experimental results show that, compared to ordinary PID algorithm, the proposed fuzzy control strategy can significantly improve the new type of direct drive electro-hydraulic actuator robustness and immunity.The main research work of this thesis as following:1)Combining with the application market of the product, according to the actual needs of customers, targeting on the new direct drive electro-hydraulic actuator for the research objectives, built the platform which based on MATLAB RTW Xpc displacement control experimental. Combining the hardware and software, and Advantech PCI 1716 multifunction data acquisition card as cross-platform software and hardware, to achieve the signal acquisition and output.2)This thesis models the experimental platform by AMESim and a joint simulation with MATLAB, combines advantages of AMESim which facilitate to modeling and MATLAB which easy to write complex algorithms. With the control algorithms simulation and analysis, the thesis gets some useful directions for the debug prototype experimrnts..3)After the joint simulation of MATLAB and AMESim, carry out the prototype test platform for data collection and analysis. The measured data show that the fuzzy control algorithm in terms of robustness and anti-interference ability, compared to ordinary PID control , Have the obvious advantages, to achieve the control objectives required to realize the direct drive electro-hydraulic servo actuator ideal control.