Hardware-in-the-Loop Heat-Pump Test Rig for EV Thermal Systems

Abstract

This project successfully developed a complete, manufacturable design for a mobile, modular EV thermal system simulation test bench intended to evaluate compressor performance under realistic and repeatable operating conditions. Driven by sponsor needs and industry gaps, the final design provides a practical alternative to large-scale thermal laboratories by prioritizing affordability, safety, and adaptability without sacrificing analytical rigor. The selected hot and cold glycol tank system enables controlled thermal loading across a wide temperature range (-40°F to +120°F) while avoiding the cost, complexity, and safety risks associated with full vehicle systems, environmental chambers, or high-voltage battery integration. Coupling this thermal simulation loop with a vapor-compression refrigeration cycle allows direct measurement of compressor efficiency and coefficient of performance using standard instrumentation and data acquisition methods. The system's modular layout and use of off-the-shelf components make it suitable for repeated use in both academic and industrial lab environments. Throughout the design process, engineering decisions were guided by stakeholder requirements, benchmarking against existing solutions, and iterative modeling using MATLAB and Simulink. These analyses informed subsystem sizing, control strategies, and safety considerations, ensuring that the final design is internally consistent and technically defensible. While physical construction and validation were outside the scope of this semester, the resulting design is sufficiently detailed to support immediate fabrication and future experimental testing. Beyond the technical deliverables, this project demonstrates how complex EV thermal systems can be split into controlled, repeatable test environments that accelerate component development and comparison. By lowering the cost and logistical barriers to compressor testing, the proposed test bench supports faster iteration, improved design decision-making, and broader access to EV thermal research. With future implementation and validation, this platform has the potential to become a long-term asset for the University of Michigan EV Center and an adaptable template for industry-facing thermal testing applications.