Abstract:In order to provide a precise model of dynamic components in the electrohydraulic proportional variable pump and improve the accuracy when design a system, firstly, the mechanical structure parameters of a certain electrohydraulic proportional variable pump were measured and the basic structural parameters of the pump were confirmed. Then a single model of a piston and the model of the proportional flow servo valve and variable pump were built in AMESim software platform according to the actual parameters of the valve and pump. And the whole model of electrohydraulic proportional variable pump was constructed based on the sub models. Through the coordinated control of pressure, flow and proportional valve opening, comprehensive simulation test and experimental verification of the dynamic characteristics of the pump were carried out. The dynamic response of the simulation was consistent with the experimental data, which verified the accuracy of the model. The dynamic response of the proportional flow servo valve spool, the angle of the swash plate and the system pressure could be observed directly in the model. The response speed of proportional flow servo valve, valve opening gain and diameter of control piston in this simulation model were adjusted further so effects of these parameters on the dynamic response of the swash plate were obtained. The results show that the swash plate will response more quickly with bigger valve opening gain, faster proportional flow servo valve response, and smaller diameter of the control piston. However, when the valve opening gain gets too large, the swash plate overshoot will increase and it will affect the dynamic characteristics of the swash plate. In this paper, an accurate simulation model was provided for the theoretical research and engineering selection of the electrohydraulic proportional variable pump.
