Sliding Mode Control-based Strategy for Direct Bus Voltage Control in Flywheel Energy Storage
Due to its high instantaneous power and power density,flywheel energy storage has found wide application in energy storage microgrids and high-power UPS systems.Flywheel systems can quickly disburse energy which facilitates regulation of output frequency and voltage of microgrids.However,when the energy storage flywheel is discharging in a wide speed range,it is difficult to avoid mutual exclusion of high dynamic response and low speed stability,and conse-quently dynamic performance and discharge depth of the flywheel are seriously affected.To improve dynamic response and stability of flywheel energy storage in discharge mode,this paper puts forward sliding mode control-based constant-switch-frequency direct power control strategy.The control strategy facilitates simultaneously high dynamic performance and low speed stability and improves flywheel's utilization rate by 7.5％,as it makes the flywheel to achieve a 45％ increment of load mutation voltage recovery time,and to maintain stable following voltage within low speed section.The feasibility of this control strategy is confirmed through simulation analysis.
flywheel energy storagedynamic responsesliding mode controldischarge depth
万方数据
维普
