Grid Forming Control Tuning for a Hybrid Inverter-Based Resource Power Plant

Journal Article · Tue Dec 09 00:00:00 EST 2025 · IEEE Transactions on Sustainable Energy

DOI:https://doi.org/10.1109/TSTE.2025.3642072· OSTI ID:3015507

Fan, Lingling ^[1]; Miao, Zhixin ^[1]; Ramasubramanian, Deepak ^[2]

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1. Univ. of South Florida, Tampa, FL (United States)
2. EPRI, Knoxville, TN (United States)

A hybrid inverter-based resource (IBR) power plant consists of grid-following (GFL) and grid-forming inverter-based resources (GFM-IBR) connected in parallel. Here, this research focuses on how to design and tune GFM's control parameters to ensure stable operation of the hybrid power plant for weak and strong grid conditions. We consider two design cases: one where the GFL-IBR does not provide frequency support, and one where it does. It is found that the GFM's power-frequency synchronizing system can lose stability when the power-frequency droop constant is large and/or the grid is strong. Additionally, if the GFL has its frequency support enabled, oscillation stability worsens. To explain the mechanism of the interactions, we construct a feedback system for the synchronizing loop, which consists of the GFM's power-frequency droop control that generates the GFM's synchronizing angle, the GFL's phase-locked loop that measures the voltage phase angle, the GFL's frequency-power control that generates its power order, and the rest of the system. The feedback system is effective in illustrating the potential stability risks. Successful design ensures that the hybrid power plant can operate smoothly and ride through grid disturbances.

• Research Organization: Univ. of South Florida, Tampa, FL (United States)
• Sponsoring Organization: USDOE Office of Energy Efficiency and Renewable Energy (EERE), Renewable Power Office. Solar Energy Technologies Office
• Grant/Contract Number: EE0011474
• OSTI ID: 3015507
• Journal Information: IEEE Transactions on Sustainable Energy, Journal Name: IEEE Transactions on Sustainable Energy; ISSN 1949-3029; ISSN 1949-3037
• Publisher: IEEE
• Country of Publication: United States
• Language: English

Related Subjects

feedback systems
grid-following
grid-forming
inverter-based resources
oscillations