Dynamic Simulation Of Load-Sensing Variable Displacement Piston Pump

Demanding on environment-protected and energy-saving product of the modern industry development promotes the new type high efficiency and energy-saving variable displacement pump. Variable displacement pump's control style has many ways, such as constant pressure, constant fluid, constant power, electrohydraulic proportional and load-sensing etc. Load-sensing variable displacement pump mainly use piston pump, system can auto feedback the signal changes of fluid to the variable controlled part of the pump, changing the pressure parameter and providing the right power for load. Therefore it can greatly decrease the power loss and increase the efficiency of the original source.The research subject is the load-sensing variable displacement piston pump for loader's steering system. The working principles of load-sensing variable displacement pump for loader's steering system is analyzed and the mathematic model of direct-operation and pilot-operation variable displacement piston pump is established. System's fluid and pressure simulation models are set up using Matlab/Simulink. Simulating the dynamic response of the pump when loader steering in the low, middle and high velocity and the load pressure surpass the safety pressure. At last, change several parameters of the pump, analyze the influence to the pump's fluid and pressure dynamic response through simulation. It can provide theoretical basis for the system optimization.