Modeling and Mitigation of Resonance Current for Modified LCL-Type Parallel Inverters With Inverter-Side Current Control

Autor: Chenghui Zhang, Xiangyang Xing, Bin Duan, Boxue Zhang, Rui Zhang, Xiaoyan Li
Rok vydání: 2022
Předmět:
Zdroj: IEEE Transactions on Industrial Informatics. 18:932-942
ISSN: 1941-0050
1551-3203
DOI: 10.1109/tii.2021.3076090
Popis: Modified LCL-type filter is adopted in parallel three-level inverters for high-frequency zero circulating current mitigation. However, it will generate internal resonance circulating current (IRCC) and external resonance circulating current (ERCC), which causes the output current unstable unavoidably. To address this issue, in this article, the model of IRCC and ERCC is established and analyzed. It reveals that the IRCC and ERCC are highly related to inverter-side zero sequence circulating current (ISZSCC) and common-mode voltage. Therefore, IRCC and ERCC can be suppressed by controlling the ISZSCC. To suppress the resonance currents, the ISZSCC model is first set up. Furthermore, a controller of ISZSCC is proposed and the parameters designing process of closed-loop controller are elaborated to stabilize the system based on the established model. Moreover, the resonance current suppression is achieved by adjusting the duty times of common-mode small vectors in space vector modulation. Thus, the current waveform quality and system stability are greatly improved after applying the proposed method. Finally, simulation and experiments results prove the effectiveness of theoretical analyses and proposed control strategy.
Databáze: OpenAIRE