抄録
In hybrid electric vehicles (HEVs), the power network takes an ever-important role, which functions to adjust the engine operating region for less emissions, to incorporate the electric machine for higher overall efficiency, and to feed the increasing demand of electric loads with different voltage levels. Furthermore, more and more mechanically, pneumatically or hydraulically driven systems are gradually superseded by electrically driven systems. In this paper, the key issues, the main components, the powertrain arrangements and the voltage levels of the power network in HEVs are discussed.