分布式独立二次调压电液控制系统设计与仿真

Design and Research of Distributed Independent Secondary-pressure-regulating Electro-hydraulic Control System

通过多路阀实现负载敏感电液控制(LS)系统等集中式液压系统流量分配,会产生较大的节流损失,能量效率较低。分布式独立电液控制系统(DIEHCS)采用单泵单执行器的排量控制方式,基本消除节流损失,节能效果显著,但普遍存在独立式驱动装机功率大、分布式安装结构不紧凑等问题。为此,本文以6 t挖掘机为对象,提出了一种分布式独立二次调压电液控制系统(DIEHCS-SPR)。该系统主要由3个独立布置于臂架上的开式电液执行器(EHA)及1个恒压控制的主泵(布置于舱室内)组成。各EHA根据执行器预期速度和负载力方向实现四象限工况的精确运转。6 t挖掘机虚拟样机仿真结果表明,在同一个工作周期下,提出的DIEHCS-SPR系统相比于LS系统节能率可达42%~46%。相比于现有DIEHCS,所提出系统各EHA峰值输出功率最高可降低70%~74%,可显著减小各EHA外形尺寸和质量,不仅节约了关键元件(EHA)的制造成本,更降低了分布式安装时自重所产生的额外能耗。

Centralized hydraulic systems such as load-sensing electro-hydraulic control(LS)systems realize flow distribution through multiple valves,resulting in large throttling losses and low energy efficiency.The distributed independent electro-hydraulic control system(DIEHCS)adopted the displacement control mode of single pump and single actuator,which basically eliminated throttling loss and had remarkable energy-saving effect,but there were many problems such as large installed power of independent drive and uncompact distributed installation structure.Therefore,a distributed independent secondary-pressure-regulation electro-hydraulic control system(DIEHCS-SPR)was proposed for a 6 t excavator.The system consisted of three open electro-hydraulic actuators(EHAs)which independently arranged on the manipulator and a constant pressure main pump(arranged in the cabin).Each EHA achieved four-quadrant operation according to the expected actuator speed and load direction.The simulation results of 6 t excavator virtual prototype show that proposed DIEHCS-SPR was compared with LS system,the energy saving rate was up to 42%~46%under the same working cycle.Compared with the existing DIEHCS,the proposed system can reduce the peak output power of each EHA by up to 70%~74%,resulting in a significant reduction in individual EHA dimensions and weight,while saving key component(EHA)manufacturing costs and additional energy consumption from self-weight during distributed installation.