The Energy–Power Requirements for HEV Power Train Modeling and Control

Abstract

The first step in the hybrid vehicle power train design, of course, after choosing the drive architecture, is the analysis of the power distribution and energy flow between the Internal Combustion Engine (ICE) (considered in this book only as the primary source of energy – PS) and the energy accumulator (called the source of power, or a secondary energy source – SS). The role of the Primary Source (PS) is to deliver to the system the basic energy, while the Secondary Source (SS) feeds the hybrid power train during its peak power loads and stores the vehicle’s kinetic energy during the regenerative braking. The target of these considerations is to search for the minimal necessary power of the Primary Source (PS) and the minimal energy capacity of the Secondary Source (SS). Certainly, this computation requires the proper energy flow model and the basic vehicle driving cycle, in the role of which the statistic driving cycle is recommended. The main aim of this chapter is the depiction of the above problem, as well as the finding of its solution. The background of the energetic evaluation of the hybrid drive structure is the dynamic determination of the internal watt efficiency of each of the propulsion system’s components. The complex construction of the hybrid drives requires an appropriate control strategy from its designers. In order to achieve this aim numerical optimization methods of nonlinear programming can be applied.