This study presents an improved super-twisting sliding mode (SSM) approach to a stand-alone doubly fed induction generator (DFIG) for direct current (DC) generation system. By taking the uncertainties into consideration, an improved SSM regulator based on an extended state observer (ESO) is proposed to enhance the robustness of DC-voltage regulation. Moreover, a novel sinusoidal rotor current calculation method is proposed to generate sinusoidal reference of rotor current. A resonant-based ESO (R-ESO) SSM approach is proposed to regulate rotor current. By applying the R-ESO to estimate the model-related part of DFIG, the tracking performance with respect to a sinusoidal reference is improved. Then, the suppression ability to fifth and seventh harmonic currents are enhanced. Finally, both simulations and experiments on a 6-kW DFIG-DC system are provided to show the effectiveness of DC-voltage regulation and harmonic current suppression of the proposed approach.

中文翻译：

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具有谐波电流抑制功能的独立DFIG-DC系统的改进的超扭曲滑模控制

这项研究提出了一种改进的超扭曲滑模（SSM）方法，用于直流电（DC）发电系统的独立双馈感应发电机（DFIG）。通过考虑不确定性，提出了一种基于扩展状态观察器（ESO）的改进的SSM稳压器，以增强DC电压调节的鲁棒性。此外，提出了一种新颖的正弦波转子电流计算方法来生成转子电流的正弦波参考。提出了一种基于共振的ESO（R-ESO）SSM方法来调节转子电流。通过应用R-ESO估计DFIG的模型相关部分，相对于正弦参考的跟踪性能得到了改善。然后，增强了对五次和七次谐波电流的抑制能力。最后，