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The modern bulk power system operation is complex and dynamic, with rapidly increasing inverter-based resources and active distribution systems. Therefore, high-speed monitoring is required to operate the power system reliably and efficiently. Transmission network topology processing (TNTP) is vital in power system control. Today’s TNTP is based on supervisory control and data acquisition (SCADA) system monitoring of relay signals (SMRS). Due to the slow data communication rate, SMRS cannot efficiently support the modern bulk power system’s energy management system (EMS) functions. In this study, a physics-based hierarchical TNTP (H-TNTP) approach based solely on node voltages and branch currents measurements is proposed utilizing artificial intelligence algorithms. H-TNTP includes the identification of substation configuration. The reliability of the H-TNTP is guaranteed by the design with inherent verification. If required, H-TNTP is capable of operating concurrently with the TNTP-SMRS. A power system with solar photovoltaic (PV) plants is utilized as a test system to illustrate the proposed H-TNTP approach. Results indicate that H-TNTP is fast with synchrophasor measurements. Furthermore, to demonstrate the application of the reliable and fast TNTP approach in EMSs, fast automatic generation control (AGC) during contingencies is studied. Typical results show that fast reconfiguration of AGC modes and dispatch factors leads to better frequency regulation.
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This content will become publicly available on May 29, 2026
Scalable Δ -AGC Logic for Enhanced Electromechanical Oscillation Damping in Modern Power Systems With Utility-Scale Photovoltaic Generators
Power systems with utility-scale solar photovoltaic (PV) can significantly influence the operating points (OPs) of synchronous generators, particularly during periods of high solar PV generation. A sudden drop in solar PV output due to cloud cover or other transient conditions will alter the generation of synchronous generators shifting their OPs. These shifted OPs can become a challenge for stability as the system may operate closer to its stability limits. If a disturbance occurs while the system is operating at the shifted OP, with reduced stability margins, it will be more vulnerable to increased oscillations, loss of synchronism of its generator(s) and system instability. This study introduces a scalable delta-automatic generation control (delta-AGC) logic method designed to address stability challenges arising from shifts in the OPs of synchronous generators during abrupt drops in PV generation. By temporarily adjusting the OPs of synchronous generators through modification of their participation factors (PFs) in the AGC logic dispatch, the proposed method enhances power system stability. The proposed delta-AGC logic method focuses on the optimal determination of delta-PFs in power systems with large number of generators, using the concept of coherency and employing a hierarchical optimization strategy that includes both inter-coherent and intra-coherent group optimization. Additionally, a new electromechanical oscillation index (EMOI), integrating both time response analysis (TRA) and frequency response analysis (FRA), is utilized as an online situational awareness tool (SAT) for optimizing the system’s stability under various conditions. This online SAT has been implemented in a decentralized manner at the area level, limiting wide-area communication overheads and any cybersecurity concerns. The delta-AGC logic method is illustrated on a modified IEEE 68 bus system, incorporating large utility-scale solar PV plants, and is validated through real-time simulation. Various cases, including high-loading conditions with and without power system stabilizers, conventional AGC logic, and delta-AGC logic, are carried out to evaluate the effectiveness of the proposed delta-AGC logic method. The results illustrate the performance and benefits of the delta-AGC logic method, highlighting its potential to significantly enhance power system stability.
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- PAR ID:
- 10638555
- Publisher / Repository:
- IEEExplore
- Date Published:
- Journal Name:
- IEEE Access
- Volume:
- 13
- ISSN:
- 2169-3536
- Page Range / eLocation ID:
- 95288 to 95306
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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