Study on the start-up control strategy of DFIG wind farm via MMC-HVDC grid connection

Abstract

The flexible DC transmission technology proposed in recent years has significant technical advantages over other transmission methods for long-distance grid-connected transmission of large-capacity wind farms. However, as the scale of wind farms continues to expand, new problems have emerged, mainly in the form of start-up control as the basis for the reliable grid-connected operation of wind turbines. In this paper, a start-up control strategy for DFIG wind farms connected to the grid via MMC-HVDC is proposed for DFIG wind farms via flexible DC outgoing transmission scenarios, mainly including MMC-HVDC controlled rectifier start-up control and single DFIG start-up control. Finally, the correctness and feasibility of the proposed control strategy are verified by simulation.