Gain-scheduling-based droop control for universal operation of small wind turbine systems

Universal operation of small-power wind turbine systems (grid-connected and island mode) may increase their penetration in the power systems. This paper proposes the use of gain scheduling to adapt the droop control gains to the different operation modes. It allows to achieve fast dynamic response in grid-connected mode and small voltage and frequency variations in island mode. An energy storage system contributes to ensure power balance between the wind turbine and the loads demand in island mode. The effectiveness of the proposed control method is verified by simulation and experimental results.