Abstract:By taking the in series heavy hydraulic hybrid vehicles as the study object, the rulebased energy management strategy was presented, and four modes of whole vehicles operation were designed. The simulation model of whole vehicles for Matlab/Simulink was established. The total demand power, engine power, hydraulic system recovery power, accumulator flow, State of Charge (SOC) and other parameters for simulation of hydraulic hybrid vehicles were performed. The torque operating points of engine of the traditional vehicles and hydraulic hybrid vehicles were analyzed and compared. Simulation results show that: The power provided by the hydraulic hybrid vehicles engine and hydraulic system can meet the total demand of power requirements, which fuel economy is improved significantly, SOC is kept within reasonable limits, the engine is worked smoothly, and the design of energy management strategy is reliable and effective.