Research on Decoupling Active Disturbance Rejection Control Strategy for Active Radial Bearings Based on Kalman Filter

Flywheel energy storage boasts advantages such as rapid response, high energy density, and long service life, rendering it with a broad application prospect in power grids with a high proportion of renewable energy generation. It is instrumental in grid frequency regulation and the smoothing of fluctuations in renewable energy generation [1]. Active Magnetic Bearings are deemed a crucial component of Flywheel Energy Storage Systems (FESS) due to their capability for contactless operation and ensuring optimal performance without the need for lubrication during high-speed rotation. However, the modeling and control of Active Magnetic Bearings remain challenging issues [2]. A typical FESS comprises five key components: the flywheel motor, flywheel rotor, bearings, vacuum chamber, and bi-directional converter [3], among which the active bearings are particularly critical. The modeling of active radial bearings involves unbalanced force terms, and the system is subject to disturbance forces. Moreover, the control precision requirements for active radial bearings are high, and the white noise in the system cannot be overlooked. Therefore, to ensure the stable operation of the flywheel energy storage system, this paper establishes a decoupling active disturbance rejection control strategy for Active Radial Bearings Based on Kalman Filter. Compared to PID control, this method eliminates 98.5% of the white noise and low-frequency disturbances in the system, which is of significant importance for the stable operation of the flywheel energy storage system.