基于机液压差补偿的负载口独立液压系统设计

In order to overcome the problems of high energy consumption and low efficiency in traditional valve-controlled hydraulic systems caused by using a single valve spool to control both the inlet and outlet oil circuits simultaneously, an independent metering hydraulic system has emerged. In the research on the motion control of the independent metering hydraulic system, the electro-hydraulic differential compensation method is mostly used. This method has disadvantages such as large amount of calculation, complex method and high cost. Therefore, this paper analyzes the working principle and characteristics of the mechanical-hydraulic differential compensation method. According to the principle of the mechanical-hydraulic differential compensation method, five two-position two-way proportional valves are used as the main control valves, and a pressure compensator is selected to compensate for the pressure difference at both ends of the inlet control valve. With auxiliary components such as shuttle valves, directional valves and overload make-up valves, an independent metering control valve based on mechanical-hydraulic differential compensation and an independent metering hydraulic system for the working mechanism of an excavator are designed, and a physical test platform is built, thus providing a good test basis for the subsequent research on the control characteristics of the independent metering hydraulic system.

为了克服传统阀控液压系统由于其采用一根阀芯同时控制着进、出口油路，而造成的能耗大、效率低，出现了负载口独立液压系统。在负载口独立液压系统运动控制的研究中，大多采用电液压差补偿方法，此种方法具有计算量大、方法复杂、成本高等缺点，为此，本文分析了机液压差补偿方法的工作原理及其特点，根据机液压差补偿方法的原理，采用5 个二位二通比例阀作为主控制阀，选用压力补偿器对进口控制阀两端的压差进行补偿，配以梭阀、换向阀、过载补油阀等辅助元件，设计了基于机液压差补偿的负载口独立控制阀，以及挖掘机工作机构负载口独立液压系统，并搭建了实物试验平台，从而为后续负载口独立液压系统的控制特性研究提供了良好的试验基础。