In modern vehicles, effective thermal management is crucial for regulating temperatures across various components and sub-systems, ensuring optimal performance, efficiency, safety, and passenger comfort. As the industry shifts towards reducing carbon emissions, powertrain electrification - encompassing electric and hybrid vehicles - has emerged as a prominent trend. This transition introduces greater complexities, as the powertrain system must now precisely control the temperatures of not only traditional components but also batteries, power electronics, and motors.
Typically, the performance of vehicle-level thermal management systems is fully evaluated only after physical prototypes are developed and tested, particularly during summer and winter road trials. Conducting development and validation at such a late stage in the development process significantly increases both development risks and costs.
To address these challenges, a comprehensive vehicle-level thermal management simulation platform has been developed for a plug-in hybrid vehicle (PHEV). This platform integrates all components and subsystems of the thermal management system, including full control of the thermal system. Using this platform, vehicle-level simulations under various driving conditions in real-world scenarios can be performed, enabling the evaluation of vehicle technical specifications during the early development phase. Furthermore, individual components, subsystems, and control strategies can be designed and optimized through virtual assessments.
This paper outlines the development of a vehicle-level comprehensive simulation platform, detailing various component-level and system-level models, as well as control and calibration methodologies. Validations were conducted under the summer road test condition and the WLTC test at an ambient temperature of 38°C. The platform's capabilities are demonstrated through application examples in PHEV thermal management development, including optimization of compressor operations for minimizing energy consumption, evaluation of traction motor temperature rise during consecutive uphill starts, and analysis of direct cooling designs for battery packs using refrigerants.