Grid Fault-Resilient Control of a PMSG- based Tidal Stream Turbine

摘要

This paper describes a grid fault-resilient control approach for a grid-connected tidal stream turbine (TST) driven by a permanent magnet synchronous generator (PMSG). TSTs mainly use conventional PI controllers while they are very sensitive to grid faulty conditions. In this faulty context, the TST will experience power generation decrease and dynamic performance degradations. Indeed, the grid-side converter can be deactivated and the generator may be disconnected from the grid. Also, grid faults can make the system instable during and after faults occurrence, which can deteriorate the quality of the power injected into the grid from the TST generation system. In this paper, a resilient controller is therefore derived to enhance the PMSG-based TST performance during grid fault. In fact, high-order sliding modes have been adopted to sustain a minimum level of optimal performance and achieve a smoother grid- injected power in case of a grid fault. Simulations carried out on real tidal speed data measured at the Raz de Sein site in Bretagne in France clearly highlights proves the effectiveness of the proposed grid fault-resilient approach.