Accurate Modeling of Saucer-Shaped Flywheel Battery Based on Magnetic Field Estimation and Virtual Air Gap Transformation

In this study, a modeling method of magnetic suspension flywheel battery based on magnetic field estimation and virtual air gap transformation is proposed, and a typical saucer-shaped flywheel battery with special structure is taken as an example for accurate modeling. Firstly, the magnetic field is segmented and carefully estimated to make precise calculations for some places where leakage and edge fluxes are severe. Then, the torsional air gap is cleverly equivalent to the virtual air gap, which solves the problem of how to balance the torsional modeling and control detection accuracy of this kind of deformed structure. Finally, after the above series of processing, the five-degree-of-freedom (5-DOF) suspension force model of the saucer-shaped flywheel battery is obtained. Finally, the accuracy and performance tests are carried out. Good experimental results verify the theoretical feasibility and the control system based on the model can make the flywheel battery have good anti-interference performance.