Cabin air quality and energy savings in electric vehicles by using a smart filtration system

M. Lesage*, D. Chalet, Ecole Centrale de Nantes; L. del Fabbro, E. Le Nain, Renault SAS, J. Migaud*, MANN+HUMMEL, France; D. Ebnet, MANN+HUMMEL GmbH, Germany

Heating and cooling of the cabin air drains energy especially for electric vehicles. This energy comes from the battery, and, as a consequence, cannot be used for car propulsion. In addition, requirements are more and more important concerning the cabin air quality. The objective is to protect the passengers from ultrafine particles or harmful gases by using advanced filtration technologies (HEPA filter, adsorption). Compared to houses or buildings, car passengers are confined in only a few cubic meters volume. Cabin air quality depends on fresh and recirculated air flows. As a consequence, filtration solutions are developed and implemented in the HVAC (Heating, Ventilation and Air Conditioning) system.

From the outside to the cabin, the system studied in this paper is composed of three individually adjustable elements: ambient filter, HEPA filter and cabin filter. These different stages are activated depending on the air pollution level of the environment and driving conditions (traffic jam, tunnel, city, outbackā€¦) with possibility to minimize the energy consumption for heating or cooling. In addition, different sensors (particles, gases, temperatureā€¦) monitoring the indoor and outdoor air quality can be used in order to optimize the filtration system regulation. In reality, for typical driving conditions, ambient air enters by infiltration (depending on the vehicle speed), allowing particles, NOx, SOx, and NHx to enter into the cabin but not through the HVAC system (and as consequence not through the filters). The infiltration level depends on the cabin pressure and the vehicle speed.

In this article, a compromise was found between fresh air and recirculation mode for every driving condition, number of passengers, history, outside air pollution level, energy consumption level and cabin thermal management system...

Session: G2 - Cabin Air Filters
Day: 22 October 2019
Time: 14:45 - 16:00 h

Learn more at FILTECH 2019 - Register Now!