STATCOM and DFIG Reactive Power Management Strategy for LVRT Capability Enhancement Under Asymmetrical Grid Faults

In the trajectory of carbon dioxide (CO2) neutrality, wind and solar energies will be the key for the energy transition in the electricity sector; however, a massive integration of solar and wind farms into the electricity grid by 2050 will be carried out. For this end, powers control and powers management of these two renewable energies have taken the attention of several researchers since the last decades. This article presents a reactive energy management strategy for a power grid linked to a wind farm utilizing doubly fed induction generators (DFIG) and enhanced by a static reactive power compensator (STATCOM). This management strategy improves an electrical grid capability in the event of a low-voltage ride through (LVRT) and aims to optimize the sizing of the STATCOM to be installed alongside the wind farm. The proposed oriented voltage control strategy (VOC) for the grid-side converter and STATCOM facilitates effective reactive current injection into the grid during symmetrical faults with significant voltage sags. A maximum power point tracking (MPPT) approach combined with stator flux-oriented control (FOC) applied to the rotor side converter enables effective control of the DFIG during an asymmetrical fault. Breaking down currents and voltages into positive and negative sequences expressed in the synchronous frame enhances DFIG and STATCOM control during grid voltage asymmetrical faults. The control algorithms are validated by simulation results using MATLAB-SIMULINK.