On-Site Harmonic, Load Rejection Overvoltage, and Anti-Islanding Scheme Verification of a 20 MW BESS Interconnection to a Distribution Feeder

Abstract

The guiding principles of climate change have driven the adoption of large-scale variable sources of renewable generation. The consequential application of energy storage is imperative to enable the integration of renewable variable sources by enhancing resource adequacy and supporting the grid. The main realized and potential benefits of energy storage have been identified as increased system stability, dispatchability, inertia, and economics. With the declining storage prices and the proliferation of the technology, electric utilities must adapt and understand the impact of such technology into their system. Three important concerns to electric utilities are potential degradation of power quality, potential damage to customer facilities, and most importantly, the impact on safety. Harmonic emissions of inverter-based resources are always an important subject and fit the power quality description. The second concern, as identified in this paper, is load rejection overvoltage, often brought up in recent inverter-based resources research. Thirdly, identified as a safety concern, the timely detection and extinction of an island is paramount. Modern inverters contain native anti-islanding schemes that must be convincing to electric utilities if communication-based direct transfer trip is not present. Based on this background, this paper presents the operational field verification of a 20MVA, 20MWh (1C) battery energy storage system connected to a 25kV distribution feeder. Measurement results were collected and analyzed during the commissioning phase and the results are reported in this paper.