Abstract The quality of output current of L C L -type voltage source inverter (VSI) is degraded by the grid voltage distortion, the dead time effect, and the parameter mismatches. This paper proposes a novel fractional order harmonic disturbance observer-based control (FOHDO) for the three-phase L C L -type inverter to suppress all the dc- and ac-component periodic disturbances. Firstly, a harmonic disturbance observer based control for L C L -type inverter is proposed with the internal model knowledge of the periodic disturbances signals. Subsequently, the FOHDO based on Lagrange interpolating polynomial fractional order delay approximation is put forward to enhance the adaptability of the grid frequency. Then, the stability and robustness performance of the proposed FOHDO for L C L -type inverter are evaluated, which also involves a detailed parameter design process. Finally, the effectiveness and performance of the proposed FOHDO method are verified by both experimental and simulation results.

中文翻译：

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三相LCL型逆变器的分数阶谐波扰动观测器控制

摘要 LCL型电压源逆变器(VSI)的输出电流质量受到电网电压畸变、死区时间效应和参数失配等因素的影响。本文为三相 LCL 型逆变器提出了一种基于分数阶谐波干扰观测器的新型控制 (FOHDO)，以抑制所有直流和交流分量周期性干扰。首先，利用周期扰动信号的内模型知识，提出了一种基于谐波扰动观测器的LCL型逆变器控制方法。随后，提出了基于拉格朗日插值多项式分数阶延迟近似的FOHDO，以增强电网频率的适应性。然后，评估了所提出的用于 LCL 型逆变器的 FOHDO 的稳定性和鲁棒性性能，其中还涉及详细的参数设计过程。最后，通过实验和仿真结果验证了所提出的 FOHDO 方法的有效性和性能。