Hardware-in-the-loop testbed for evaluating heat pump energy flexibility control strategies: Design, evaluation, and experiment

This paper presents a comprehensive overview of the newly developed hardware-in-the-loop testbed and its applications in testing heat pump energy flexibility and smart grid control. The study begins by reviewing stateof-the-art hardware-in-the-loop testbeds and highlighting the distinctive features of the newly developed testbed. An analytical framework for evaluating heat pump energy flexibility and smart grid control is proposed, detailing dynamic testing procedures. The design of the testbed, which includes both hardware and software components, is thoroughly described. Subsequent sections evaluate the testbed's quality and provide an overview of a demo experiment that assesses heat pump control strategies under dynamic price signals. The results indicate a high level of fidelity in the thermal system testbed emulation, with tracking errors as low as 1.55% observed in the Heat Dock and Hot Dock emulators, affirming its reliability for dynamic testing and validation of control algorithms under realistic conditions. The demo experiment showcases the effectiveness of the testbed in assessing heat pump control strategies, revealing a 7.5% reduction in operating costs achieved by an advanced control algorithm compared to the reference mode. Overall, the newly developed hardware-in-the-loop testbed emerges as a valuable tool for validating advanced control strategies in smart grid-ready heat pump systems.