Bt25 High-pressure Flow Of The Electro-hydraulic Proportional Speed Control Valve Design And Research

High-pressure and Heavy-flow Electro-hydraulic Proportional Flowrate Regulating Valve (HHFV) is being used in more and more fields. Today, however, the internal and external researches of HHFV are still on the first step. Actually, present researches can't simultaneously satisfy the needs of high pressure , heavy flow and high precision .Moreover, the structure of the existed HHSV is too complicated, and the price is too expensive. i Aiming at heavy flow control under high pressure situation, simple structure and moderate precision and according to the actual demands, the researches of HHFV have been done as follows:(1) Creatively designed a new HHFV (named as BT25 for short). The body of BT25 is constructed by a pilot throttling valve with position feedback and a pressure compensated valve. The proportional amplifier applies the technology of Plus Width Modulation(PWM), allows tow signals to input and can automatically change the ramp time according to kind of signal.(2) The study of the performance of BT25 has been described. Through the study of the pilot valve and the pressure compensated valve, the author has deduced the formula of the pressure gain of the pilot valve and the judging formula of the stability of the pressure compensated valve, which will give a great help when designing or testing HHFV. The thesis also theoretically analyzed the load step response of BT25 in an actual system.(3) By means of Power Bond Graphs, a dynamic mathematical model and a stable-state mathematical model of BT25 have been built and the two models have been used to simulate the characteristics of the stable-state control ,the stable-state load and the voltage step response . Simulation results show that BT25 allows easy passing of heavy flow and that the power to resist load is strong and the speed of response is sensitive.(4) Some experiments have been done to test BT25 and some relevant analyses of the test results have been taken. It is shown that the performance of BT25 satisfies all the control requirements and accords with the simulation results very well.To sum up, the researches in this thesis brings a successful design of HHFV. The experiences can be generalized in other situations.