液压挖掘机混合动力系统节能特性及试验研究

Energy Saving Performance and Experimental Study on Hybrid System of Hydraulic Excavator

针对目前液压挖掘机能量利用率低、油耗高的问题,分析挖掘机在典型作业工况下的能量损耗,确定混合动力系统进行节能研究的重要方向.根据混合动力挖掘机的特点,提出基于超级电容与电机的并联式油电混合动力系统方案,以山河智能公司20吨级液压挖掘机为平台建立系统仿真模型,对系统动力耦合特性、控制策略及超级电容SOC等因素给混合动力挖掘机节能效果带来的影响进行理论计算和仿真分析,并对系统关键参数进行了优化匹配.搭建液压挖掘机混合动力系统试验平台,对系统的节能效果进行试验验证.研究结果表明,采用油电并联混合动力系统,并选择合适的动力耦合参数、瞬时优化控制策略及超级电容SOC补偿参数有利于提高液压挖掘机的节能指标,节能效率可改善20%以上.

Based on low utilization rate of energy and high fuel consumption,the energy losses in the hydraulic excavator during typical working condition were analyzed,and the major directions of the energy saving research for the hybrid power system were derived.A parallel hydraulic electric configuration for hybrid excavator was proposed based on capacitor and motor.For the hybrid power system based on SUN-WARD 20T hybrid excavator,the paper established simulation model,and the effect of the power coupling characteristics,the control strategy,the capacitor’s State Of Charge on the hybrid excavator were studied by contrast calculation and simulation.And the key parameters were optimized and matched.At last the energy saving effect was studied by building test platform of hybrid system,and found that adopting the parallel hydraulic electric system,selecting the appropriate parameters in power coupling,instantaneous optimization of control strategy,compensating parameter of capacitor SOC are helpful to improve the ener-gy saving effect of hybrid excavator,and the energy saving efficiency can reach above 20%.