{"paper":{"title":"Revisiting Voltage and Synchronization Stability Analysis in Converter-Integrated Weak Grids: Insights from Non-Minimum-Phase Zeros","license":"http://creativecommons.org/licenses/by-nc-nd/4.0/","headline":"Non-minimum phase zeros in the grid Jacobian transfer matrix cause both voltage instability and synchronization issues in weak grids with converter-interfaced generators.","cross_cats":["cs.SY"],"primary_cat":"eess.SY","authors_text":"Fuyilong Ma, Huanhai Xin, Lennart Harnefors, Lidong Zhang, Linbin Huang, Waisheng Zheng, Wangqianyun Tang","submitted_at":"2026-05-13T06:33:42Z","abstract_excerpt":"The increasing penetration of converter-interfaced generators (CIGs) intensifies concerns over small-signal voltage and synchronization stability. While existing theories treat these two stability issues distinctly, practical wisdom in contrast employs a unified and static metric, short-circuit ratio (SCR), to assess both in weak grids. This paper aims to bridge this theory-practice gap by introducing the insight of non-minimum phase (NMP) zeros. First, we demonstrate that the two stability issues in weak grids originate from NMP zeros in the grid Jacobian transfer matrix: a zero at the origin"},"claims":{"count":4,"items":[{"kind":"strongest_claim","text":"We demonstrate that the two stability issues in weak grids originate from NMP zeros in the grid Jacobian transfer matrix: a zero at the origin corresponds to voltage instability, while low-frequency zeros impose fundamental constraints on synchronization dynamics. The traditional SCR is proven to be a special case of our proposed novel stability metric, NMP-zero (NMP-Z) factor, evaluated at the rated operating point.","source":"verdict.strongest_claim","status":"machine_extracted","claim_id":"C1","attestation":"unclaimed"},{"kind":"weakest_assumption","text":"The analysis relies on small-signal linearization of the system around an operating point and the assumption that the grid Jacobian transfer matrix fully captures the relevant dynamics for both voltage and synchronization stability.","source":"verdict.weakest_assumption","status":"machine_extracted","claim_id":"C2","attestation":"unclaimed"},{"kind":"one_line_summary","text":"Non-minimum-phase zeros in the grid Jacobian explain both voltage and synchronization instability in weak grids, with the short-circuit ratio as a special case of the proposed NMP-Z factor at rated operating point.","source":"verdict.one_line_summary","status":"machine_extracted","claim_id":"C3","attestation":"unclaimed"},{"kind":"headline","text":"Non-minimum phase zeros in the grid Jacobian transfer matrix cause both voltage instability and synchronization issues in weak grids with converter-interfaced generators.","source":"verdict.pith_extraction.headline","status":"machine_extracted","claim_id":"C4","attestation":"unclaimed"}],"snapshot_sha256":"4982e569703968a61e12e867432c76b9fa82ac6f07cddc5b688e54ff2dc7b4ff"},"source":{"id":"2605.13061","kind":"arxiv","version":1},"verdict":{"id":"05bf8d23-7e75-45e1-9049-5363b50e7f3f","model_set":{"reader":"grok-4.3"},"created_at":"2026-05-14T19:01:49.579702Z","strongest_claim":"We demonstrate that the two stability issues in weak grids originate from NMP zeros in the grid Jacobian transfer matrix: a zero at the origin corresponds to voltage instability, while low-frequency zeros impose fundamental constraints on synchronization dynamics. The traditional SCR is proven to be a special case of our proposed novel stability metric, NMP-zero (NMP-Z) factor, evaluated at the rated operating point.","one_line_summary":"Non-minimum-phase zeros in the grid Jacobian explain both voltage and synchronization instability in weak grids, with the short-circuit ratio as a special case of the proposed NMP-Z factor at rated operating point.","pipeline_version":"pith-pipeline@v0.9.0","weakest_assumption":"The analysis relies on small-signal linearization of the system around an operating point and the assumption that the grid Jacobian transfer matrix fully captures the relevant dynamics for both voltage and synchronization stability.","pith_extraction_headline":"Non-minimum phase zeros in the grid Jacobian transfer matrix cause both voltage instability and synchronization issues in weak grids with converter-interfaced generators."},"references":{"count":27,"sample":[{"doi":"","year":2022,"title":"Power system stability with a high penetration of inverter-based resources","work_id":"59bfb504-9f29-4014-ad22-ff9c489bae94","ref_index":1,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":2021,"title":"Definition and Classification of Power System Stability – Revisited & Extended,","work_id":"d9a3a638-7f58-459b-838b-d65d6c7cdbe0","ref_index":2,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":2020,"title":"Small-Disturbance V oltage Stability of Power Systems: Dependence on Network Structure,","work_id":"98b1c71b-6da7-42bb-a6bb-287cab57d7c9","ref_index":3,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":2022,"title":"Real-world subsynchronous oscillation events in power grids with high penetrations of inverter-based resources,","work_id":"08beef4d-a64e-495b-a6a7-e06fbea03d64","ref_index":4,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":2020,"title":"Grid-synchronization stability of converter-based resources—an overview,","work_id":"b0965963-b2c8-4b28-b877-363165041a54","ref_index":5,"cited_arxiv_id":"","is_internal_anchor":false}],"resolved_work":27,"snapshot_sha256":"af46a8b2f00867a90ea5e301f56f1cab5431385ed3a686f5be809a43bb6ffe0e","internal_anchors":0},"formal_canon":{"evidence_count":2,"snapshot_sha256":"47fd2141eebe98944c98158f3740681c3eec07afba243bf989d858c9bc8b8c23"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}