Adaptive approach for primary frequency support by wind turbines based on grid code requirements and turbines limitations

Abstract

Based on the provisions of grid support published in the latest network codes (NC), wind turbines (WTs), among other renewable energy units, must regulate their output power to actively participate in supporting the grid frequency. However, the most frequently utilized wind turbines with doubly fed induction generators (DFIG) have limitations regarding rotor speed and converter power in addition to issues related to their power output resulting from wind speed fluctuation and model-plant mismatch. In this paper, rotor side converter of WT operated in de-loading mode is controlled adaptively. The objective is to provide transmission system operator (TSO) with an accurate available power and mitigate the influence of wind disturbances while following TSO variable power set-point. The limitations of both rotor speed and rotor side converter are considered in the proposed control approach.