In order to solve the problems of large peak torque and short battery life when the city battery bus starts or accelerates, a new electro-hydrostatic hydraulic hybrid powertrain is designed in this paper that can operate efficiently in all speed conditions with a certain type of electric bus running in Chengdu. The improvement of comprehensive energy efficiency of power system by switching between different power modes under typical operating conditions is studied. Through the co-simulation of AMESim and MATLAB/Simulink-stateflow software, the vehicle and control models are established and the rule-based dynamic optimal energy management strategy is set. The dynamic performance and energy utilization characteristics of New European Driving Cycle and the cycle condition of investigation under actual driving environments are analyzed. The core problems of energy coupling of electro-hydrostatic hydraulic hybrid powertrain are studied experimentally to verify the correctness of the design thought and simulation model. The results show that under the premise of satisfying the dynamic performance, the designed electro-hydrostatic hydraulic hybrid system can effectively improve the overall average efficiency of operating point of the electric motor and greatly reduce the peak torque. The peak torque is reduced by 36.4% and the battery power consumed by the selected cycle is reduced by 33.98% under New European Driving Cycle conditions. Under the actual cycle conditions, the peak torque is reduced by 28.9%, and the battery power consumed by the selected cycle is reduced by 32.3%.

中文翻译：

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电瓶客车电液静液压混合动力系统设计与能源利用

为解决城市电瓶客车启动或加速时峰值扭矩大、电池寿命短的问题，本文设计了一种新型的电液静液压混合动力系统，可在所有速度条件下以某种类型的电动车高效运行。成都公交车。研究了典型工况下通过切换不同功率模式来提高电力系统综合能效的问题。通过AMESim与MATLAB/Simulink-stateflow软件的联合仿真，建立整车和控制模型，制定基于规则的动态优化能量管理策略。分析了新欧洲驾驶循环的动力性能和能量利用特性，并在实际驾驶环境下进行了调查的循环条件。对电液静液压混合动力总成能量耦合的核心问题进行了实验研究，验证了设计思想和仿真模型的正确性。结果表明，在满足动态性能的前提下，所设计的电液静液压混合系统能够有效提高电机工作点的整体平均效率，并大大降低峰值扭矩。在新欧洲驾驶循环条件下，峰值扭矩降低 36.4%，所选循环消耗的电池电量降低 33.98%。实际循环工况下，峰值扭矩降低28.9%，所选循环消耗的电池电量降低32.3%。