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Enhanced Large-Signal Stability Method for Grid-Forming Inverters During Current Limiting: Preprint

Conference ·

Grid-forming (GFM) inverters are a promising technology for the widespread integration of renewable energy sources in future power systems. As a key element of GFM inverter control, the primary controller governs the internal reference voltage and angle. During contingencies in the grid---such as faults, voltage drops, or frequency and phase jumps---an inverter can be forced into a current-limiting mode of operation modulating inverter dynamics, and, as a result, it is prone to losing synchronism with the grid. In this paper, we propose a novel GFM primary control method with an additional synchronization term that naturally activates during contingencies to improve the dynamic response. The method allows the inverter to remain synchronized with the grid, which improves the inverter's dynamic behavior both during and after current-limiting grid conditions and enhances grid support, including voltage support using full current capacity. The method is demonstrated for voltage, frequency, and phase jumps both in a single-machine-to-infinite-bus and a network-wide electromagnetic transient simulation of the IEEE 14-bus system with 5 GFM inverters. The simulations provide insights into the proposed synchronization method and confirm the high potential of the method, which robustly secures synchronism under severe contingencies.

Research Organization:
National Renewable Energy Laboratory (NREL), Golden, CO (United States)
Sponsoring Organization:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Renewable Power Office. Solar Energy Technologies Office; USDOE National Renewable Energy Laboratory (NREL), Laboratory Directed Research and Development (LDRD) Program
DOE Contract Number:
AC36-08GO28308
OSTI ID:
2000738
Report Number(s):
NREL/CP-5D00-86296; MainId:87069; UUID:dc84e232-7ba7-4bdf-9137-6100812caff4; MainAdminID:70568
Resource Relation:
Conference: Presented at the IEEE 24th Workshop on Control and Modeling for Power Electronics (COMPEL), 25-28 June 2023, Ann Arbor, Michigan; Related Information: 87689
Country of Publication:
United States
Language:
English

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