双馈风电机组无撬棒故障穿越技术研究综述

The failure of fault ride through (FRT) will lead to large-scale chain off-grid accidents of wind power, which seriously threatens the safe and stable operation of modern power system. For doubly-fed induction generator (DFIG)-based wind turbines, the crowbar circuit is widely used to realize FRT. Nevertheless, this scheme has some inherent defects, such as the loss of control ability, large torque ripple, and excessive reactive power absorption, etc., and it is difficult to adapt to increasingly strict grid standards. In recent years, many scholars have carried out extensive research on crowbar-less FRT technology and proposed a series of FRT control methods. However, there are few works dedicated to summarizing and analyzing this topic. For this issue, this paper presents a comprehensive review of crowbar-less FRT technology for DFIG-based wind turbines. Firstly, the latest technical specifications related to FRT in the grid code of various countries are summarized. Then, the technical points and state quo of crowbar-less FRT technology are sorted out and compared. Finally, the future research and development direction is discussed and prospected from the aspects of new technical specifications, new operation scenarios and new control modes of wind turbines.