Sustained environmental pollution and energy crisis are constantly promoting the development of hybrid electric vehicles. Among many configurations, the power-split ones based on planetary gear have special advantages of energy saving potential and velocity conversion characteristics. Thus it has attracted considerable attention in related fields. Power-split system based on dual-planetary gear provides a variety of energy flow modes, so it is suitable for constructing a multi-mode hybrid power-system for hybrid electric commercial vehicles. In this paper, a power flow model for the vehicle with such configuration is constructed; the energy flow relationship is analyzed and optimized. The optimal power flow relationship can be used to guide the division of working modes of hybrid electric vehicles and also provided a model basis for further study of related energy management strategies.
Keywords power-split hybrid electric vehicle, dual-planetary gear, power flow model, energy management strategy