Journal of Power Electronics

  • 제20권2호
  • /
  • Pages.410-427
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  • 2020
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  • 1598-2092(pISSN)
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  • 2093-4718(eISSN)
전력전자학회 (The Korean Institute of Power Electronics)
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DOI QR코드

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Enhanced robustness with damping interval widening strategy of LCL-type converter under weak grid condition

  • Wang, Qi (College of Electrical and Power Engineering, Taiyuan University of Technology) ;
  • Qin, Wenping (College of Electrical and Power Engineering, Taiyuan University of Technology) ;
  • Wang, Lei (College of Electrical and Power Engineering, Taiyuan University of Technology) ;
  • Han, Xiaoqing (College of Electrical and Power Engineering, Taiyuan University of Technology) ;
  • Wang, Peng (College of Electrical and Power Engineering, Taiyuan University of Technology)
  • 투고 : 2019.04.20
  • 심사 : 2019.10.11
  • 발행 : 2020.03.20
⟨ 이전 논문 다음 논문 ⟩

초록

Active damping methods are widely adopted to present a damping effect on the resonance phenomenon without the power loss of LCL-type converters connected to a grid. However, extra sensors are used to implement the damping strategy. In this paper, a sensorless damping strategy where only the grid current is sampled has been proposed. Furthermore, the inner relationship between the tradition capacitor current feedback strategy and the proposed strategy has been clarified. Considering the digital delay and a weak grid, a robust method that uses unit delay feedback to mitigate the phase lag and to widen the effective damping interval has been developed. With this simple measure, stability is enhanced during the Nyquist frequency and robustness is improved when the LCL parameters vary and grid impedance exists. Finally, simulation and experimental results are presented to verify the feasibility and engineering significance of the proposed strategy.

키워드

과제정보

This work was supported by Shanxi Province Science and Technology Major Project (20181102028), National Key R&D Program of China (2018YFB0904700), National Natural Science Foundation for Youth of China (51807130), Natural Science Foundation of Shanxi Province (201701D121134) National Natural Science Foundation of China (U1610121).

참고문헌

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