2026-04-05T12:48:15Zhttps://recercat.cat/oai/request

oai:recercat.cat:2117/4265802026-03-31T12:53:03Zcom_2072_1033col_2072_452950

00925njm 22002777a 4500 dc Liu, Ni author Wang, Hong author Zhou, Weihua author Song, Jie author Zhang, Yiting author Prieto Araujo, Eduardo author Chen, Zhe author 2025-01-01 With the increase of the renewable energy generator capacity, the requirements of the power system for grid-connected converters are evolve, which leads to diverse control schemes and increased complexity of systematic stability analysis. Although various frequency-domain models are developed to identify oscillation causes, the discrepancies between them are rarely studied. This study aims to clarify these discrepancies and provide circuit insights for stability analysis by using different frequency-domain models. This study emphasizes the limitations of assuming that the transfer function of the self-stable converter does not have right half-plane (RHP) poles. To ensure that the self-stable converters are represented by a frequency-domain model without RHP poles, the applicability of this model of grid-following (GFL) and grid-forming (GFM) converters is discussed. This study recommends that the GFM converters with ideal sources should be represented in parallel with the P/Q-¿/V admittance model rather than the V-I impedance model. Two cases are conducted to illustrate the rationality of the P/Q-¿/V admittance model. Additionally, a hybrid frequency-domain modeling framework and stability criteria are proposed for the power system with several GFL and GFM converters. The stability criteria eliminates the need to check the RHP pole numbers in the non-passive subsystem when applying the Nyquist stability criterion, thereby reducing the complexity of stability analysis. Simulations are carried out to validate the correctness of the frequency-domain model and the stability criteria. Postprint (published version) Àrees temàtiques de la UPC::Enginyeria elèctrica Grid forming Impedance Power system stability Frequency-domain analysis Analytical models Grid following Integrated circuit modeling Voltage control Stability criteria Power system dynamics Converter Grid-forming (GFM) Grid-following (GFL) impedance Renewable energy Stability analysis Frequency-domain model Hybrid frequency-domain modeling and stability analysis for power systems with grid-following and grid-forming converters