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arXiv · 2309.01278

Under-frequency Load Shedding for Power Reserve Management in Islanded Microgrids

Bei Xu·Victor Paduani·Qi Xiao·Lidong Song·David Lubkeman·Ning Lu
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Abstract

This paper introduces under-frequency load shedding (UFLS) schemes specially designed to fulfill the power reserve requirements in islanded microgrids (MGs), where only one grid-forming resource is available for frequency regulation. When the power consumption of the MG exceeds a pre-defined threshold, the MG frequency will be lowered to various setpoints, thereby triggering UFLS for different levels of load reduction. Three types of controllable devices are considered for executing UFLS: sectionalizers, smart meters, and controllable appliances. To avoid unnecessary UFLS activation, various time delay settings are analyzed, allowing short-lived power spikes caused by events like motor startups or cold-load pickups to be disregarded. We tested the proposed UFLS schemes on a modified IEEE 123-bus system on the OPAL-RT eMEGASIM platform. Simulation results verify the efficacy of the proposed approaches in restoring power reserves, maintaining phase power balance, and effectively handling short-lived power fluctuations. Furthermore, in comparison to sectionalizer-based UFLS, using smart meters or controllable loads for UFLS allows for a more accurate per-phase load shedding in a progressive manner. As a result, it leads to better balanced three-phase voltage and serves more loads.

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BibTeXRIS

Bei Xu, Victor Paduani, Qi Xiao, Lidong Song, David Lubkeman, Ning Lu. 2023-09-06. Under-frequency Load Shedding for Power Reserve Management in Islanded Microgrids. https://arxiv.org/abs/2309.01278

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