Compensation Strategy of Wideband Voltage Harmonics for Doubly-Fed Induction Generator

Compensating voltage harmonics is the advanced target for doubly-fed induction generator under the harmonically distorted grid, which is also an essential function in the process that wind power generation system evolves into supporting or regulating grid from adapting grid. To overcome the weakness of the existing methods that only can compensate harmonics with pre-known frequency, a modified derivation controller is designed to compensate the voltage harmonics with fixed and unfixed frequencies in this paper. This article firstly investigates the critical factors that affect the harmonics compensation capability of DFIG based on harmonic mechanism analysis. Then, the design thought and design procedure of the proposed control strategy are detailly presented. Further, the performance comparisons between the proposed control and the traditional control are analyzed to theoretically signify the superiority of the proposed strategy. Finally, the tests on the hardware in loop platform are done to verify the validity and effectiveness of the proposed control strategy.