Advancements in Building-to-Grid Interactions: Thermo-Electric Coupling Models of Motor-Driven Devices

Building-to-grid (B2G) integration transforms buildings into active components of the electricity grid, enhancing dynamic energy management and optimizing usage to reduce operational costs and carbon emissions. However, existing modeling tools for building and power systems often overlook or oversimplify the interactions between power system dynamics and building dynamics. This paper introduces Modelica-based thermo-electric coupling models for motor-driven devices in buildings, such as pumps and heat pumps. The developed models assess transient oscillations and negative active power in these devices within B2G systems. We compare the proposed models with a base model from the Modelica Building Library that uses a radiator and heat pump to maintain room temperature. The simulation results demonstrate that the motor-driven models effectively capture transient oscillations in current and power when the systems are activated and deactivated. Additionally, the occurrence of negative power when systems turn off is a critical factor in enhancing B2G system stability and energy efficiency. These findings underscore the model's ability to improve grid support, advancing energy management practices in B2G applications.