Analysis and Modeling of Multi-Physical Field Coupling Characteristics of Magnetic Bearing System for Flywheel Energy Storage

The flywheel energy storage system, as an efficient and environmentally friendly energy storage method, has broad application prospects in areas such as grid peak regulation and integration of new energy sources. The magnetic bearing, as the core supporting component of the flywheel rotor, its performance directly affects the stability and efficiency of the system. In response to the problem of decreased modeling accuracy of the flywheel energy storage magnetic bearing system due to the multi-physical field coupling during actual operation, this study systematically analyzed the electromagnetic field, thermal field, structural field of the magnetic bearing system, as well as the interaction mechanisms among these multiple physical fields. Through feature extraction based on the coupling mechanism, this study proposed a suspension force modeling method based on coupling characteristic factors. These factors can characterize the parameter changes of the magnetic bearing system under multi-physical field coupling, and integrating these factors into the model can achieve dynamic correction of the traditional suspension force model. The research results show that the correction model established based on the multi-physical field coupling characteristic factors has a model that is closer to the actual working conditions compared to the traditional model, and has higher model accuracy, providing an accurate model for the stable control of the flywheel energy storage system.