Plug-in Hybrid Vehicle Thermal Management and System Operation in Real-World Conditions
2022-01-0824
03/29/2022
- Event
- Content
- Plug-in hybrid electric vehicles (PHEVs) can use stored electrical energy from the grid as well as chemical energy from fuel for both propulsion and auxiliary loads (such as cabin heating and cooling). Using their electrified powertrains, these vehicles are designed to achieve improved overall efficiency and lower emissions when compared to conventional vehicles. Real-world conditions may, however, require significant thermal management loads (based on ambient temperatures), lowering vehicle efficiency and potentially increasing tailpipe emissions. A series of on-road tests were completed in Canadian summer and winter conditions in order to characterize the operation of four 2018 model-year PHEVs: a minivan, an SUV, and two hatchbacks. Their various thermal management equipment and control strategies are discussed, including electric air-conditioning systems, electric coolant heaters, advanced heat pump systems, and engine waste heat recovery (conventional heater cores). The results are analyzed in terms of operation strategy, thermal management loads, and tailpipe CO2 emissions. In summertime, all vehicles were able to run all-electrically for significant distances at the start of each test day, thanks to their electric air-conditioning systems. In wintertime, two vehicles with electric coolant heaters immediately started their engines to boost heat production for the cabin but used their stored electrical energy for heat and propulsion as well. One vehicle had an advanced heat pump system, allowing it to run all-electrically for significant portions of winter testing (although for a shorter distance than in summer testing). The last vehicle had no electrical heating capability, requiring engine use whenever cabin heat was requested but blending in electrical energy for propulsion whenever possible.
- Citation
- Humphries, K., Veenendaal, J., Kanmaz, K., and Loiselle-Lapointe, A., "Plug-in Hybrid Vehicle Thermal Management and System Operation in Real-World Conditions," SAE Technical Paper 2022-01-0824, 2022, .