Architecture Optimization of Hybrid Electric Vehicles with Future High-Efficiency Engine

Abstract

The great development of engine technologies can help to improve the engine characteristics and performance: a better thermal efficiency and an extending fuel economy area, which will subsequently decrease the fuel consumption and thus influence the overall architecture of the vehicle. In this paper, an investigation is carried out to assess the influence of the high-efficiency engine on the transmission gear numbers. First, according to the relevant studies and the integration of the advanced engine technology, a future engine fuel consumption map is obtained, based on which, the preliminary simulations are applied to explore the best match between the transmission and the proposed future engine from the perspective of fuel consumption. The simulation results indicate that the transmission with four gears is the best option to match the future engine while maintaining good fuel economy and meeting the driving demands. Then, based on this conclusion, a new hybrid powertrain architecture, which includes four gears for the engine, is introduced and analyzed in detail, with the advantage of seamless gear shift due to the compensation torque of the motor. Finally, to further examine the fuel economy and gear shift quality of the proposed powertrain, the dynamic model is established and the simulation results demonstrate that the new powertrain architecture shows a good fuel consumption performance and the gear shift process can be achieved without power interruption.

Reactivity controlled compression ignition engine: Pathways towards commercial viability

“…Combined with advanced combustion modes, electrification seems to have potential to reduce the overall CO2 generated emissions by the vehicle fleets [105,106]. In comparison to conventional SI engine, LTC aims to increase fuel economy for HEVs, where the electrification of the powertrain will provide extra power to drive the vehicle and decouple the engine and the battery, making it easier for the engine to operate in a high-efficiency area [107]. A considerable amount of work has been conducted to investigate the various LTC strategies such as the HCCI concept in series HEVs [108,109].…”

Identifying Roadway Physical Characteristics That Contribute to Emissions Differences between Hybrid and Conventional Vehicles

“…As the future fleet of passenger vehicles becomes increasingly comprised of blended propulsion types, like the combined ICE/EM in a typical HEV, the influence of physical roadway characteristics on fuel economy and emissions will be impossible to overlook. Drive control with the ICE and the EM is typically controlled by a local optimization strategy aimed at maximizing vehicle performance relative to the driving demands, or VSP, being experienced ( 19 ).…”

Research Progress on Electric and Intelligent Vehicles

“…Hybrid EVs have also been a research focus in this Special Issue. Hong et al [16] conducted an investigation to assess the influence of the high-efficiency engine on the transmission gear numbers. Xu et al [17] investigated an electric variable transmission for hybrid electric vehicles (HEVs).…”