Characteristic Research Of Closed-Loop Control Of Axial Variable Displacement Piston Pump

Electro-hydraulic proportional axial variable piston pump has many virtues, such as saving energy compact structure simplify system design and easy to achieve automatic control, many well-known domestic and foreign enterprises are actively engaging in development and application of electro-hydraulic proportional axial variable piston pump. Electro-hydraulic proportional axial variable piston pump has become a key component of hydraulic system, it's development will be able to make hydraulic system reach to the high pressure high efficiency and high power density direction. As the prices of such products abroad , the after-sale service and the delivery cycle,many enterprises are actively developing and applying their own products to fill gaps in this field. In order to save costs, shorten their development cycle and analyze technical difficulties, we can use computer simulation to provide theoretical basis and reference for the design of pump.The electro-hydraulic proportional axial variable piston pump made in a corporation which is regarded as the studying object in this paper.Firstly, the working principle of closed-loop control system of the electro-hydraulic proportional variable piston pump is analyzed, pressure control mathematical model and flow control mathematical model of the closed-loop control system are set up on the basis of the analysis. Secondly, M file is carried out in MATLAB and system control diagram is described in the Simulink, then we carry flow dynamic characteristic simulation and pressure dynamic characteristic simulation through the step signal.Under the reasonable condition , we change the parameters of the components in the system,and then analyze the influence on the dynamic performance of the system.and then, we analyze the dynamic performance of the three distribution orifices and compare with their advantages and their disadvantages. At last,we do the performance comparison of the open-loop system and closed-loop system to testify theoretical analysis.Dynamic characteristic of closed-loop control system of the electro-hydraulic proportional axial variable piston pump are tested through the simulation in some specifical condition, which offers theoretical foundations of the following design and reform.