The investigation of the innovative hybrid heat pump system designed and prototyped for heating process of electric vehicles

In this paper, the investigation of the innovative hybrid heat pump system (HHPS) included Positive Temperature Coefficient (PTC) heater commonly used in electric vehicles (EVs) was performed in different heating modes to reach the desired temperature in a target time. The developed HHPS was evaluated in different heating modes in order to reach the desired temperature considering the both target time and also vehicle driving range. It was shown that the driving range can be increased up to 15 % by using HHPS. As a result, a high-capacity PTC heater and HP should be work together at the beginning of the heating, and then the PTC capacity should be reduced gradually at lower ambient conditions. Another important result is that HHPS represent a promising solution for the new generation EVs that the target temperature was obtained lower than 300 s at lower ambient conditions. A numerical model was also developed to investigate the flow and the thermal characteristics of the EV cabin interior that enable to design more effective heating, ventilation and air-conditioning (HVAC) systems of EVs under different environmental conditions and the numerical results were in good agreement with the experimental data used in this study.(c) 2023 THE AUTHORS. Published by Elsevier BV on behalf of Faculty of Engineering, Alexandria University. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/ licenses/by-nc-nd/4.0/).

Automated summary

This paper investigates the innovative hybrid heat pump system (HHPS) with a Positive Temperature Coefficient (PTC) heater commonly used in electric vehicles (EVs) in different heating modes. The results show that using HHPS can increase the driving range of EVs by up to 15%. It is suggested that a high-capacity PTC heater and heat pump should work together at the beginning of heating, and gradually reduce the PTC capacity at lower ambient conditions. HHPS is a promising solution for achieving the target temperature in less than 300 s at lower ambient conditions in new generation EVs.