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With the increased inverter-based resources (IBRs) connected to the grid, IBR P-Q capability charts are needed, proposed, and developed by the power industry to assure IBR operation efficiency and reliability. This paper presents a comprehensive P-Q capability evaluation for an IBR plant interconnected with the transmission grid. The proposed study considers the impact of different IBR grid-connected filters, IBR vector control implementation in the dq reference frame, and special interconnection nature of IBRs in a plant structure. The models and algorithms developed for the IBR P-Q capability analysis have considered specific IBR constraints that are different from those of a synchronous generator. The paper especially focuses on exploring the P-Q capability characteristics of IBRs and IBR plant at different interconnection points that are important for managing, designing, and controlling IBRs within an IBR plant, and for the development of international standards, such as IEEE P2800, for connecting IBRs to the transmission and distribution grids in a plant structure.
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This content will become publicly available on June 24, 2026
Dynamic Security Assessment of Systems Powered Only by Grid-Forming Power Plants with Uncertain Dispatch Using Polynomial Vectors
A modern challenge in power engineering is to perform the dynamic security assessment (DSA) of grids that are 100% powered by inverter-based resources (IBRs). Addressing this challenge is difficult because: (i) the dispatch of IBRs can be uncertain as a result of the variability of renewable resources and (ii) they have hard current control limits that cannot be neglected, contrasting synchronous machines. To address this problem, this paper sets forth a framework to conduct DSA of bulk power systems that are 100% powered by grid-forming IBRs. The framework considers that IBR operational conditions are unknown but bounded by a zonotope which is also expressed as a polynomial vector for uncertainty propagation via Dormand–Prince integration. The framework is applied to modified versions of the WSCC 9-bus and IEEE 39-bus grids.
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- PAR ID:
- 10608883
- Editor(s):
- Vaccaro, Alfredo
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Journal Sustainable Energy, Grids and Networks
- ISSN:
- 2352-4677
- Subject(s) / Keyword(s):
- Dynamic security assessment, power system stability, uncertainty.
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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