Power Generation Strategy of FESS Based on Sliding Mode and Linear Active Disturbance Rejection Control

Flywheel energy storage system (FESS) is often used as an uninterruptible power supply (UPS) in the process of power generation. At this time, in order to supply power to the load stably, it is necessary to maintain the stability of the DC bus voltage. The characteristic of high frequency charging and discharging required by flywheel energy storage makes the bus voltage easily deviate from the given value. In this paper, the control strategy of flywheel motor in power generation mode is studied. On this basis of the double closed-loop control of traditional controllable bi-directional converter, a compound control strategy based on sliding mode and linear active disturbance rejection control is designed. Compared with the disturbance compensation method of load current feedforward, this method can estimate and eliminate the uncertain disturbance in real time and effectively when the DC bus load changes or the bus voltage is subject to other internal and external disturbances, So that the bus voltage can respond quickly and maintain stability when disturbed, and realize effective and reliable uninterrupted power supply.