Aiming at the adverse effect of the peak power of the electric motor of the battery-powered rail vehicles on the battery life and the driving range when starting or accelerating, a new type of electro-hydrostatic hydraulic hybrid powertrain is designed. This article proposes a novel power form that assists the vehicle to start or accelerate through two power coupling methods: torque coupling circuit and flow rate coupling circuit which have good power performance and energy-saving performance. A mathematical model for power coupling of hybrid power system is constructed, and the effects of key parameters of the system and different power coupling ratios on electric power consumption and power coupling characteristics are studied. Based on the simulation and test platform, the power coupling characteristics of the electro-hydrostatic hydraulic hybrid powertrain are simulated and experimentally researched. The results show that compared with the traditional electro-hydrostatic series system, the novel electro-hydrostatic hydraulic hybrid powertrain can effectively avoid the impact of electric motor power and reduce the power consumption. Based on the characteristics of power coupling, the acceleration strategy of minimum peak power is studied to control the key components of the power coupling process. Simulation and experimental results show that under the control of the new acceleration strategy, the electro-hydrostatic hydraulic hybrid powertrain has good electro-hydraulic power coupling characteristics. The electric power of the power system is greatly reduced during acceleration, which has better energy-saving characteristics and value for engineering applications.

针对电池供电的轨道车辆的电动机峰值功率在启动或加速时对电池寿命和续驶里程的不利影响，设计了一种新型的电动静液压混合动力总成。本文提出了一种新颖的动力形式，通过两种动力耦合方法协助车辆启动或加速：扭矩耦合电路和流量耦合电路，具有良好的动力性能和节能性能。建立了混合动力系统功率耦合的数学模型，研究了系统关键参数和功率耦合比对功率消耗和功率耦合特性的影响。基于仿真测试平台，对静液压液压混合动力总成的动力耦合特性进行了仿真和实验研究。结果表明，与传统的电液静压串联系统相比，新型的电液静压液压混合动力总成可以有效避免电动机动力的影响，降低动力消耗。根据功率耦合的特点，研究了最小峰值功率的加速策略，以控制功率耦合过程的关键环节。仿真和实验结果表明，在新的加速策略的控制下，电动静液压混合动力总成具有良好的电液动力耦合特性。在加速过程中，电力系统的电力大大降低，