PROJECT TITLE :

Analysis and active damping of multiple high frequency resonances in DFIG systems - 2017

ABSTRACT:

As the wind power generation develops, the doubly fed induction generator (DFIG) based mostly wind power system is more and more seemingly to control in the rising weak network instead of in the standard stiff network. Thanks to the comparatively giant impedance of the weak network than the stiff grid, the DFIG system may be subject to the resonances thanks to the impedance interaction between the DFIG system and the weak network. Especially, when connected to a series p sections weak network, the multiple high-frequency resonances (MHFR) could occur and need careful studies. The impedance modeling of the DFIG system and also the series p sections weak network is first demonstrated in this paper. Then, thanks to the multiple magnitude peaks of the series p sections of the weak network, the MHFR can be created and will be theoretically explained primarily based on the impedance modeling results. For the purpose of mitigating the MHFR, a vigorous damping strategy that introduces a virtual impedance, including a part leading compensation unit and a virtual positive resistance, is proposed and demonstrated. Simulations are conducted to validate the DFIG system MHFR furthermore because the proposed active damping strategy.