出口压差补偿的负载口独立控制系统防气穴特性研究

Characteristics of Cavitation Prevention of Independent Metering Control System with Outlet Differential Pressure Compensation

摘要:

传统液压系统采用1根阀芯同时控制液压执行器进出口油路，系统能耗大、效率低，且在主动型负载工况下，易出现气穴现象。为防止液压缸在主动型负载工况下产生气穴现象，本文分别对传统液压系统、负载口独立控制系统、进口压差补偿负载口独立控制系统和出口压差补偿负载口独立控制系统4种液压系统防气穴特性进行了理论分析，获得了进、出口阀开口度比μ与空气分离压力Pm、负载力FL等参数之间的关系，建立了4种液压系统仿真模型，设置相同负载力FL、进口阀开口度K1等仿真参数，仿真结果表明，除传统液压系统外，其他3种负载口独立控制系统均可以通过改变μ使进口压力Pa大于0，从而避免气穴现象，且出口压差补偿负载口独立控制系统无需检测负载力FL。通过试验验证了仿真结果的可行性。

Abstract:

The traditional hydraulic system used a sliding spool to control the inlet and outlet oil ways of the hydraulic actuator at the same time, as a result that the system had high consumption, low efficiency, and was prone to cavitation under active load conditions. In order to prevent cavitation phenomenon of hydraulic cylinder under the active load condition, the anti-cavitation characteristics of four hydraulic systems were analyzed theoretically, including the traditional hydraulic system, the independent metering control system, the independent metering control system with inlet differential pressure compensation and the independent metering control system with outlet differential pressure compensation. The relationship between the opening ratio μ of inlet and outlet valves and parameters such as air separation pressure Pm and load force FL was obtained. Four hydraulic system simulation models were established, and the same load force FL, inlet valve opening K1 and other simulation parameters were set, the simulation results showed that in addition to the traditional hydraulic system, the other three independent metering control systems can avoid cavitation phenomenon by changing the opening ratio μ of inlet and outlet valves, and the independent metering control system with outlet differential pressure compensation did not need to test the load force FL. Finally, the feasibility of the simulation results was verified by the experiments.