Evaluation of Different Powertrain Topologies for a Premium Plug-in Hybrid Electric Vehicle

Plug-in hybrid electric vehicles combine the benefits of both battery electric and internal combustion engine drivetrains. There are multiple possibilities for hybrid configurations, each with its own advantages and disadvantages. In this study, two newly developed traction electric machines were employed alongside a gasoline engine in various hybrid configurations. These configurations, ranging from P1 to P4 and their combinations, were evaluated in terms of vehicle performance, energy consumption, and emissions. The impact of battery capacity was also examined. With a larger battery providing higher discharge power, the electric acceleration time significantly decreases from around 8.6 seconds to approximately 5.2 seconds as the battery capacity increases from 20 kWh to 40 kWh in configurations featuring two traction electric machines. In hybrid mode, the reduction in acceleration time is less pronounced, with a decrease of around 0.7 seconds compared to the configuration with a 20 kWh battery. Under high-load conditions, such as driving uphill with a trailer, the gasoline engine can handle all selected cases with high brake thermal efficiency. The vehicle was also simulated under the certification test with different utility factors in accordance with future European emissions legislation. To achieve a similar certified number as a vehicle with a 20 kWh battery in 2025, vehicles produced after 2027 will need a battery capacity of 40 kWh. The discussion on the suitable hybrid topology for future premium PHEVs was conducted by balancing vehicle performance and energy consumption in both electric and hybrid modes.