Research On The Control Characteristics Of Electro-hydraulic Proportional Variable Displacement Axial Piston Pump

With the rapid development of modern industry, the hydraulic system is required increasingly higher. The hydraulic system is required not only to develop to the direction of high pressure and high-power, but also the requirement of dynamic performance of the system and the noise problems are gradually improved. As the power source of the hydraulic system, the requirement of the performance index of hydraulic pump is also increased day by day. With the characteristics of compact structure, energy efficiency, simplified system design, simple automatic control and others, the electro-hydraulic proportional variable axial piston pump becomes the key component in high pressure, high efficiency and high power hydraulic system.The control characteristics of the bi-directional electro-hydraulic proportional variable axial piston pump is studied in this paper. The closed-loop displacement control scheme of pump on the bases of the variable displacement piston position feedback is put forward. And the purpose of displacement control of the pump under different working conditions is achieved. Based on the new displacement control scheme, the variable resistance moment of the swash plate is analyzed through dynamic simulation to the pump with ADAMS software, and by the hydraulic simulation platform SimulationX, this paper does research on the displacement control characteristic of the electro-hydraulic variable displacement axial piston pump and by changing the variable cylinder control pressure and variable piston diameter, the impact on the control characteristics is analyzed, the displacement mechanism of the variable pump is reasonablely designed finally. Through simulation, we can provide a theoretical basis for the design and improvement of electro-hydraulic proportional axial variable piston pump.The main research work of this article are as follows:1.The general development situation of variable displacement piston pump is introduced. A variety of the variable pump control methods are briefly described, and the working principle and control characteristics of the bi-directional electro-hydraulic proportional variable axial piston pump are introduced in detail. The main factors related to the displacement control are obtained, that is the largest disturbance during the control process is the swash plate variable resistance moment. Through the analysis of the swash plate resistance moment, the decisive factors that affect the piston pump control characteristics are presented that are the variable cylinder control pressure and the variable piston diameter. The innovations of paper are elaborated.2.The swash plate variable resistance moment is calculated theoretically, which is built the theoretical basis for the subsequent simulation analysis. 3.The virtual prototyping technology is used on the kinetics simulation of axial piston pump. The variable piston pump mechanism model is established in Pro/E software, and then the model is imported into ADAMS and the kinetic model of the variable displacement piston pump is obtained. Finally the pump swash plate variable resistance moment is simulated and analyzed in various valve plate forms and different working conditions.4.Based on the working principle of the bi-directional electro-hydraulic proportional variable axial piston pump, by the simulation software SimulationX, the1D model of the hydraulic system and3D dynamic model are built up. Through the simulation of the electro-hydraulic proportional variable displacement axial piston pump under different working conditions, the variable displacement control characteristics are analyzed. Through the simulation analysis of the main decisive parameters including variable cylinder control pressure and variable piston diameter which affect the control characteristics, reasonable matching methods and values range are put forward. And the reasonable optimization design of the variable mechanism is derived to achieve the desired control characteristics.5.Make Summary of the work to the full text, and put forward the prospects for the future research work.