Research on Dual Motor Drive System of Plug-in Hybrid Powertrain

The hybrid powertrain system has a significant impact on both the overall vehicle performance and fuel efficiency. This article proposes an Intelligent Dual Drive (IDD) system, consisting of an engine, drive motor, generator, transmission, etc., which primarily relies on motor drive and can achieve all hybrid functions. Based on this, the power characteristics and basic control strategies of plug-in hybrid during Charge Depleting (CD) and Charge Sustaining (CS) stages were analyzed. P2 architecture is a conventional design solution for hybrid electric vehicles, where P stands for powertrain and 2 represents the position of both the electric motor and the generator behind the second axle.This article comparative analysis was conducted on the IDD and P2 configurations, taking the A-class vehicle as an example, and performance simulation comparisons were completed in both CD and CS stages. The research results show that the IDD performs better than P2 in the CD stage; the CS stage involves many factors, and four factors, including transmission efficiency, brake energy recovery, series-parallel efficiency, and different vehicle speeds, were compared systematically. In this stage, the IDD provides better fuel efficiency than P2, but P2 is superior to IDD in terms of cost and versatility. Based on the above analysis, it can be concluded that P2 is suitable for current product development applications, while IDD is one of the directions for the development of new energy vehicle power systems due to its lower fuel economy, stronger electrification capability, and advantages such as simple structure, compact layout, and high system efficiency.