Parameter Matching and Control of Series Hybrid Hydraulic Excavator Based on Electro-Hydraulic Composite Energy Storage

Traditional excavators driven by diesel engine have poor emissions and low energy efficiency. Pure electric driven excavators have high cost and limited endurance. Therefore, at present, hybrid power train system is an ideal candidate for excavators to realize energy-saving and emission reduction. In this paper, a novel series hybrid hydraulic excavator based on electro-hydraulic composite energy storage, which provides the average power of the system through the diesel engine, and the battery and accumulator are used as the intermediate energy storage devitalize the output current of the battery, and improve the service life of the battery, is proposed. Advantages of high energy density of battery and high power density of hydraulic accumulator are synthetically utilized. A 7-ton crawler excavator is taken as the research object, according to typical load spectrum, through analysis method and modeling method, and using dynamic programming (DP) to optimize the parameters of the novel series power train system. The control strategy of the power system is further studied, and the AMESim and Simlink co-simulation models of the transmission system is established to verify the feasibility of the system. At last, the experimental platform is built. Experiments are conducted to verify the effectiveness of the power train system.