Details

Autor(en) / Beteiligte

• Lin, Jianheng
• Su, Mei
• Sun, Yao
• Yang, Dongsheng
• Xie, Shiming
• Xiong, Wenjing
• Zhang, Guanguan

Titel

Frequency Coupling Suppression Control Strategy for Single-Phase Grid-Tied Inverters in Weak Grid

Ist Teil von

• IEEE transactions on industrial electronics (1982), 2022-09, Vol.69 (9), p.8926-8938

Ort / Verlag

New York: IEEE

Erscheinungsjahr

2022

Link zum Volltext

• IEEE_Xplore

Quelle

IEEE Xplore

Beschreibungen/Notizen

• In single-phase voltage source inverters under a weak grid, the frequency coupling, caused by the asymmetrical system structure, poses a challenge to system modeling and controller design. In this article, a frequency coupling suppression control strategy is presented, where all the frequency coupling components in the current reference are eliminated. As a result, the single-phase grid-tied inverter is directly modeled as a simple single-input single-output (SISO) admittance rather than a complicated multiple-input multiple-output admittance matrix. The SISO admittance model is simple, compact, and accurate, which facilitates design-oriented analysis. The admittance characteristic analysis shows that the Symmetrical phase-locked loop (Sym-PLL) has a critical impact on the system stability under weak grid conditions. To improve the system stability, a prefilter-based impedance-shaping control strategy is proposed by mitigating the negative resistor behavior of the Sym-PLL. Finally, simulations and experimental results validate the effectiveness of the frequency-coupling suppression control strategy.