Study on Improving LVRT Ability of Doubly-Fed Induction Generator under Asymmetric Fault

With the rapid development of wind power industry in our country, more and more large scale wind farms are connected to the electricity grid, which makes the grid safety more significant problem, so study the wind generator for the low voltage across (LVRT) technology is very significant. This paper first introduces the present research situation of the LVRT technology and the standards at home and abroad briefly, takes doubly-fed induction wind generators as research object to establish its model, discusses the various common methods to implement LVRT, focused on analysing by installing the active crowbar circuit and optimizing its resistance and shut time to improve the LVRT ability, and observing the simulation under the asymmetric power grid failure situation.