The hybrid technology brought new opportunity to energy saving of a hydraulic excavator.However, the control strategy is hard to be determined because of the complexity of working condition and cyclic fluctuation of the load. As the dynamic-work-point control strategy can not optimize the main power source and the auxiliary one simultaneously, a new control strategy based on condition recognition and hybridization optimization was presented. It optimized the power distribution rate between the two power sources according to the load condition and the SOC(state of charge) of the battery. Experimental results show that the control strategy ameliorates the speed fluctuation of the engine, optimizes the working points of the engine and SOC of battery. Ultimately it improves the fuel economy of the hybrid hydraulic excavator.

hydraulic excavator, parallel powertrain, hybridization factor, control strategy

混合动力技术给液压挖掘机节能注入了新的生机，但挖掘机工况复杂，负载波动剧烈，给控制策略的制定带来极大挑战。研究了动态工作点控制策略的不足，针对液压挖掘机工况特点，提出了一种基于工况识别和动态混合度优化的并联混合动力挖掘机控制策略。该策略根据负载和电池组的荷电状态（SOC）确定当前工况下双动力源的功率组合，实现动力性能和节能效果的综合优化。试验表明，该策略克服了动态工作点控制策略的不足，优化了发动机工作点和电池SOC工作区间，较大幅度地提高了整机的燃油经济性。

液压挖掘机, 并联混合动力, 混合度, 控制策略