@Article{ee.2026.085885,
AUTHOR = {Yihua Zhu, Tianyu Jiang, Guanming Zeng, Haoxiang Zong, Chao Luo, Chen Zhang},
TITLE = {Unified Modeling and Multi-Frequency Response Analysis of Grid-Forming Wind Power Converters under Different Grid Conditions},
JOURNAL = {Energy Engineering},
VOLUME = {},
YEAR = {},
NUMBER = {},
PAGES = {{pages}},
URL = {http://www.techscience.com/energy/online/detail/27900},
ISSN = {1546-0118},
ABSTRACT = {Grid-forming (GFM) wind power converters exhibit different small-signal frequency-response characteristics under symmetric and asymmetric grid conditions. Existing dq-frame, sequence-domain, and harmonic-domain models are often developed under different assumptions, making it difficult to compare the required model dimensions and select dominant harmonic ports within a unified framework. To address this issue, this paper develops a linear time-periodic (LTP)/harmonic state-space (HSS)-based modeling and reduction method for a virtual synchronous generator (VSG)-controlled GFM converter and derives the corresponding harmonic transfer function (HTF)-based port admittance. The proposed framework integrates periodic steady-state (PSS) computation, HSS construction, HTF-based multi-frequency coupling analysis, and reduced port-model generation. Simulink validation confirms the calculated PSS trajectories and HSS modal results. The HTF projection maps show that the dominant responses are concentrated in the same-frequency and mirror-frequency channels, while higher-order even coupling remains weak and odd-order coupling is insignificant in the considered averaged model. Equivalent single-input single-output (SISO) impedance comparisons further show that the six-port model preserves the dominant port dynamics, whereas the ten-port model provides a more conservative reduced representation. These findings provide practical guidance for harmonic truncation, harmonic-port selection, and model-dimension reduction in LTP-based stability analysis of GFM converters.},
DOI = {10.32604/ee.2026.085885}
}