Admittance stability model and equivalent circuit analysis of three‐phase AC systems in different coordinate systems

• DOI: 10.1002/cta.4147
• Publication Date: 2024-07-08T03:50:55Z
• Authors: Zhe Hu; Yang Han; Songling Zhang; Ping Yang; Amr S. Zalhaf
• Keywords: Admittance; Admittance parameters; Network Analysis

Abstract In recent years, with a large number of distributed energy sources connected to the grid, distribution network has shown clear trend towards use power electronics. As conversion interface, stability converter's interaction grid received considerable attention. Adequate admittance (impedance) modeling three‐phase grid‐connected converter is prerequisite for analyzing and resonance characteristics system. Understanding internal mechanisms proposing effective solutions are crucial enable systems effectively cope impact Therefore, by studying equivalence relationship equivalent circuit AC in various coordinate systems, this paper focuses on solving non‐uniqueness problem impedance It proposed that input asymmetrical system dq fb rotating 2‐order matrix equivalent. The unbalanced αβ “12” static 4‐order From both theoretical analysis simulation verification, it eigenvalues stationary twice system, overall damping improved. control strategy based will make more stable. second contribution establish symmetric node extend multi‐machine explain instability mechanism mechanism. Finally, frequency coupling phenomenon studied explained cannot an similar symmetrical