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The stiff dynamic model of grid-forming inverters (GFMs) presents numerical challenges in time discretization for real-time simulation, estimation, and control. To address this challenge, this paper proposes modeling GFMs as two cascading subsystems: a reference-frame-synchronization system and an in-reference-frame system. This paper demonstrates that these two subsystems are approximately linear, allowing their time discretization to be derived in closed form using the matrix exponential. The proposed discretization method is tested on the IEEE 14-bus power system with a GFM connected and compared with second- and fourth-order Runge-Kutta methods. The numerical results validate the proposed method and demonstrate its potential for discretization with longer step sizes.
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This content will become publicly available on March 1, 2026
Time Synchronization Techniques in the Modern Smart Grid: A Comprehensive Survey
In modern smart grids, accurate and synchronized time signals are essential for effective monitoring, protection, and control. Various time synchronization methods exist, each tailored to specific application needs. Widely adopted solutions, such as GPS, however, are vulnerable to challenges such as signal loss and cyber-attacks, underscoring the need for reliable backup or supplementary solutions. This paper examines the timing requirements across different power grid applications and provides a comprehensive review of available time synchronization mechanisms. Through a comparative analysis of timing methods based on accuracy, flexibility, reliability, and security, this study offers insights to guide the selection of optimal solutions for seamless grid integration.
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- Award ID(s):
- 1920025
- PAR ID:
- 10634847
- Publisher / Repository:
- MDPI
- Date Published:
- Journal Name:
- Energies
- Volume:
- 18
- Issue:
- 5
- ISSN:
- 1996-1073
- Page Range / eLocation ID:
- 1163
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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