Research on Rotor over-Current of a Doubly-Fed Induction Generator under Power Grid Fault

Abstract

This paper showed that the doubly-fed induction generator (DFIG) was sensitive to the faults of power grid. Through theoretic analysis for active power characteristic of DFIG, it was recognized that the conventional PI-based vector control strategy was likely to cause the excitation system overregulated due to lack of additional protection technique. On this condition, a DFIG risks damaged to its power converter due to overcurrent or overvoltage. At the basis of prior art, this paper developed a novel control scheme, which focused on solving overregulated problems caused by faults of power grid. The proposed control strategy was tested on an illustration DFIG-based power system modeled by MATLAB/SIMULINK. The results demonstrate that the proposed control scheme can effectively resist overcurrent under the conditions of both symmetrical and unsymmetrical grid faults.