Research On Control Strategy Of Heavy - Duty Series Hydraulic Hybrid Electric Vehicle

In recent years, the Hybrid Vehicle Technology have been caused pay greatly attentions by governments and research institutions, with its tremendous contribution in improving vehicles fuel economy and reducing exhaust emissions. Series Hydraulic Hybrid Technology is different to Hybrid Electric Vehicles and Parallel Hybrid Technology on the market, a separate Energy Management Control Strategy is required to achieve to optimize the configuration optimal energy between the Engine(the primary power source) and the Accumulator (the auxiliary power source). The engine can be decoupled with the load of the vehicle, in the structural arrangement tandem of the Series Hydraulic Hybrid vehicles, Accumulator is used to store the recovery braking energy and supplement the Engine power in appropriate conditions, in order to improve Energy efficiency and reduce Engine emissions.A Heavy Series Hydraulic Hybrid Vehicles (Heavy Series Hydraulic Hybrid Vehicles, HSHHV) Management strategy of rule-based energy is designed, for the sake of solving the former Control strategy problem. In the Matlab/Simulink simulation platform, a mathematical model and simulation model based on the physical characteristics of each major component. The power transmission relationship and the control signal input and output of rule-based control strategy are discussed. The selection of an accumulator and the bidirectional variable motor (P/M) of the main components of the Hydraulic Hybrid vehicles are detailed analyzed. The rule-based control strategy Work mode, energy allocation between Engine and Accumulator, Control strategy in Matlab/Simulink/STATEFLOW module implementation and so on are depth analyzed. Through simulation, the effect on the Control strategy are analyzed and evaluated. Compared to the traditional vehicles, Fuel economy has improved more significantly, designed control strategies reliable and effective.A Control strategy of Fuzzy Control Algorithm is studied in order to further improve Fuel economy of Hydraulic Hybrid Vehicle. Input and output variables Fuzzy set and the corresponding membership function are designed. Developed Fuzzy Controller, the Control rule bank is set, based on the physical meaning and expert knowledge experience of the controlled object. Through for the input variable speed and speed the rate of change of Fuzzy Arithmetic and Fuzzy Inference, carried on the Fuzzy decision based on the control rule bank, the working condition factor signal of the vehicle is output. In the Matlab/Simulink platform, the designed Fuzzy control strategy is verified simulation analysis. Simulation results show that:In the Fuzzy Control Strategy, Fuel economy have a certain degree improvement than the Rule-based Control Strategy, the vehicle run more smoothly.