挖掘机电液流量匹配控制系统流量补偿试验

为改善挖掘机液压系统的操控性和节能性,采用电比例泵和电比例多路阀同步控制方式的电液流量匹配控制系统.以2 t挖掘机试验样机为研究对象,分析电液流量匹配控制系统的结构原理和特点；针对挖掘机轻重负载不同工况,测试系统的压力和流量特性,通过试验研究基于压力特性的开环流量补偿方法.利用实时检测的油缸速度间接实现流量闭环控制,试验分析动臂、铲斗单执行器动作和复合动作的速度控制特性,并对系统进行变负载、变速度工况测试.试验结果表明：采用流量补偿方法提高系统的流量控制精度；电液流量匹配控制系统与负载敏感系统相比,泵的压力裕度减小0.6～0.7 MPa,提高了系统的节能性和动态响应性.

Experiment study on flow compensation of electro-hydraulic flow matching control system in hydraulic excavator

In order to obtain an advanced operation performance and an improved energy efficiency of hydraulic systems in excavators,electro hydraulic flow matching control(EFMC) systems were introduced,in which electro-proportional valves and electro-proportional pumps worked in a synchronous control mode.The principle and characteristics of EFMC systems were analyzed in the experimental prototype of 2-ton excavator that installed an EFMC system.Based on the characteristics of system pressure and flow rate,the open-loop flow compensation of the excavator was experimentally studied under the conditions of light and heavy loads.Real-time velocity was monitored and used to carry out flow closed-loop control indirectly.Both on the boom and bucket,the velocity characteristics of single and compound action were experimentally investigated with different loads and reference velocities.The experimental results indicate that the accuracy of flow control is improved by the use of flow compensation methods.Compared with the load-sensing system,the EFMC system has a more improved capability.The pressure margin of the EFMC system is reduced by more than 0.6-0.7 MPa,and the systemic performance of dynamic response and energy efficiency are improved.