Thermal Systems Technology (Sweden)

This paper presents a control-oriented thermal model for a novel heating, ventilation, and air conditioning (HVAC) system with a heat pump designed specifically for battery electric vehicles (BEVs). The model is validated through high-fidelity simulations from GT-SUITE, achieving a root mean square error of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$1.54 \,\%$</tex-math></inline-formula> for cabin air temperature and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$0.70 \,\%$</tex-math></inline-formula> for battery temperature. The model is used for exploring energy reduction strategies. Optimal results demonstrate a <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$5.7 \,\%$</tex-math></inline-formula> decrease in energy consumption during a cool-down scenario in high ambient temperatures. The usage of the model is showcased in a cabin thermal pre-conditioning problem where the vehicle is not occupied for an interval of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$600 \,\mathrm{s}$</tex-math></inline-formula> between two drives. Results show that the ability to predict occupancy and optimally manage cabin temperature could reduce energy usage by <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$12.9 \,\%$</tex-math></inline-formula>, compared to maintaining cabin temperature at the same level. Another example examines the impact of predicted data uncertainty and the result shows that it is more energy-efficient to maintain cabin thermal comfort instead of turning off the HVAC system when the likelihood of passenger arrival is uncertain and exceeds approximately <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$60 \,\%$</tex-math></inline-formula> of the predicted non-occupied interval.