Research On Variable-Displacement Control Methods And Characteristics Of Axial Piston Pump

The objective of this subject is the variable-displacement control methods and characteristics of axial piston pump. Based on the research of the variable-displacement control of some common machinary-hydraulic control pump, the subject proposes digital variable-displacement control of axial piston pump, which is based on the PWM high-speed ON-OFF valve. The subject builds the simulation models of machinary-hydraulic pressure control pump, machinary-hydraulic pressure/flow compound control pump, machinary-hydraulic pressure/flow/power compound control pump and large displacement closed axial piston pump and performs simulation and analysis for them. On this basis, the subject builds the combined simulation model of the digital variable-displacement axial piston pump to further, which is briefly called digital pump. The combination of simulation and experiment implements and verifies the pressure control, pressure/flow compound control, and pressure/flow/power compound control of the digital pump.The subject for the first time establishes the joint simulation model of the digital pump by LabVIEW and AMESim. Based on this model, the subject does some analysis on the static properties of the pressure control, pressure/flow compound control, and pressure/flow/power compound control of the digital pump. Meanwhile, the subject also does some analysis on the dynamic characteristics of the pressure control, flow control, and power control of the digital pump. Finally, the functions of the pressure control, pressure/flow compound control, and pressure/flow/power compound control of the digital pump is verified by the static property test of digital pump.The main contents of this paper are as follows:Chapter I, introduces the overview and current research of variable-displacement control of axial piston pump. By investigating the home and abroad research findings on the variable-displacement control, the research ideas of this subject and content of the research is determined and the difficulty of this subject is also pointed out.Chapterâ…¡, introduces the principles, static and dynamic performance of some common variable-displacement control pump. On this basis, their simulation models are established to further and finally, the simulation and analysis of the static and dynamic performance of these pump is carried on.Chapterâ…¢, first of all, the relationship of machinary-hydraulic pressure control pump, machinary-hydraulic pressure/flow compound control pump, machinary-hydraulic pressure/flow/power compound control pump and the pressure control, pressure/flow compound control, and pressure/flow/power compound control of the digital pump is elaborated. On this basis, the digital pump will be divided into several parts and established respectively. There are high-speed ON-OFF valve, and three control module of three control forms of digital pump. Finally, the joint model of digital pump is introduced.Chapterâ…£, the simulation and analysis of the pressure control, pressure/flow compound control, and pressure/flow/power compound control of the digital pump are performed.Chapterâ…¤, introduces the principles of digital pump test systems and verifies the static properties the pressure control, pressure/flow compound control, and pressure/flow/power compound control of the digital pump by test.Chapterâ…¥, summarizes the main contents of the paper and points out the direction of the future research.