Analysis of 0.1-Hz Var Oscillations in Solar Photovoltaic Power Plants

Journal Article · 06 November 2022 · IEEE Transactions on Sustainable Energy

DOI: https://doi.org/10.1109/tste.2022.3220083 · OSTI ID:1923501

Fan, Lingling  ^[1]; Miao, Zhixin  ^[2]; Piper, David ^[3]; Ramasubramanian, Deepak  ^[4]; Zhu, Lin ^[4]; Mitra, Parag  ^[4]

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1. Univ. of South Florida, Tampa, FL (United States); University of South Florida
2. Univ. of South Florida, Tampa, FL (United States)
3. SCE, Rosemead, CA (United States)
4. EPRI, Palo Alto, CA (United States)

Oscillations with very low frequency at 0.1 Hz, have been observed in voltage and var in practical solar photovoltaic (PV) systems when power exporting ramps up to a certain level. Here, this letter provides an explanation on the formation of 0.1-Hz oscillations and identifies three critical factors that lead to the oscillations: communication delay between the plant-level control and the inverter-level control, high volt/var sensitivity at a high power exporting level, and the volt-var feedback system consisting of the plant control, inverter control and the grid impact. Furthermore, a critical feature of the 0.1-Hz oscillation is also explained: why oscillations appear only in voltage and var, but not in real power.

• 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: EE0008771
• OSTI ID: 1923501
• Journal Information: IEEE Transactions on Sustainable Energy, Journal Name: IEEE Transactions on Sustainable Energy Journal Issue: 1 Vol. 14; ISSN 1949-3029
• Publisher: IEEECopyright Statement
• Country of Publication: United States
• Language: English