Under the circumstances where the demands for energy transition and grid energy storage technology are constantly increasing, the magnetic suspension bearing, as the core component of the flywheel energy storage system, its control strategy directly determines the dynamic response, energy efficiency level and operational reliability of the system. This study focuses on the control strategy of magnetic suspension bearings used in flywheel energy storage. Firstly, the basic structure, working principle, composition of the experimental platform and performance indicators of the magnetic levitation bearing in the flywheel energy storage system are summarized. Based on this, the core technical requirements for the grid-connected application of flywheel energy storage systems have been clarified, and it has been distilled that magnetic suspension bearings in grid scenarios need to meet three core performance requirements: high dynamic response, low operating energy consumption, and strong robust stability. Then, the control strategy of magnetic bearings is analyzed from three aspects: Firstly, the technical paths of the classical and high dynamic response control methods under high power conditions are analyzed; Secondly, the low energy consumption control technology route based on energy consumption sources is proposed; Thirdly, the application logic research of the strong robustness strategy under the disturbance scenarios of power grid faults is conducted. This study systematically reviews the technical framework of the flywheel energy storage magnetic suspension bearing control strategy, providing theoretical support and technical references for its efficient and stable application in the grid energy storage. Finally, the development trend of control strategies and future research directions are prospected.

Against the backdrop of the global clean energy transition, this paper addresses the volatility of renewable energy like wind and PV power, focusing on magnetic suspended flywheel energy storage systems (FESS). It expounds FESS’s structure (flywheel body, magnetic suspension bearings, etc.) and working principles (charging, energy retention, discharging) and studies key technologies including rotor material selection, magnetic bearing classification/modeling, motor coordination, and heat dissipation. Challenges such as high material costs and magnetic bearing stability are pointed out, with prospects for developing FESS toward higher performance, lower cost, and multi-scenario integration to support the clean transformation of power systems.