Research On Energy Management Control Strategy For Series Hybrid Bulldozer

Bulldozer as earthwork machinery,the operation condition is complex,the load changes frequently,and the traditional hydraulic mechanical transmission way have low energy utilization rate,high fuel consumption and emissions.Meanwhile,with the issue of environment pollution and energy consumption becoming seriously,As an effective energy saving and emission reduction technology,Hybrid technology is the best way to improve the fuel economy of bulldozers.For hybrid systems,a reasonable energy management strategy is the key to improving the fuel economy of bulldozers.Based on the characteristics of the bulldozer and the working characteristics of the components,the hybrid energy management strategy can realize the reasonable distribution of the multi-power source and reduce the fuel consumption of the bulldozer to achieve the goal of energy saving and emission reduction.Taking the hybrid bulldozer for the study,in order to reduce fuel consumption for the purpose of bulldozer,which focus on the Energy management strategy of series hybrid bulldozer.The main contents of this paper are as follows:(1)Through the analysis of the structure of the hybrid tracked vehicle,the structure and parameters of the series hybrid bulldozer are determined,and the working mode of the tandem hybrid bulldozer is analyzed in detail.(2)Through a modeling method which combines experimental and theoretical modeling methods.The backward simulation model is also built,including engine,generator,Super-capacitor,drive motor etc,which are implemented based on MATLAB/Simulink.To demonstrate the effectiveness of model,the driving operating performance tests are conducted in comparision with the simulation results for key component,providing a basis for the subsequent study of energy management strategy.(3)Based on the analysis of the work principle of the deterministic rule-based energy management strategy,Through the analysis and research on the principle of the deterministic rule-based energy management strategy,the power follow-up plus thermostat energy management strategy is adopted.Determine the optimal fuel consumption of the engine output power range and super capacitor SOC upper and lower limits,designed for bulldozers energy management strategy.The simulation results show that the economizer of the bulldozer is 23.1% higher than that of the traditional structure.(4)Considering the characteristics of the bulldozer,the energy management control strategy based on fuzzy control is proposed.According to the fuzzy control theory and the characteristics of vehicle models,the membership function of fuzzy controller and control rule and other related parameters were set,and the Fuzzy Control Strategy Model is completed by MATLAB Fuzzy Control Toolbox.The simulation results show that the fuel economy is improved by 25.3% compared with the traditional structure bulldozer.Compared with the deterministic rule-based energy management strategy,the energy of the whole machine can be allocated more rationally,which greatly improves the fuel economy of the bulldozer.