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arXiv · 2502.17341

Time series forecasting based on optimized LLM for fault prediction in distribution power grid insulators

João Pedro Matos-Carvalho·Stefano Frizzo Stefenon·Valderi Reis Quietinho Leithardt·Kin-Choong Yow
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Abstract

Surface contamination on electrical grid insulators leads to an increase in leakage current until an electrical discharge occurs, which can result in a power system shutdown. To mitigate the possibility of disruptive faults resulting in a power outage, monitoring contamination and leakage current can help predict the progression of faults. Given this need, this paper proposes a hybrid deep learning (DL) model for predicting the increase in leakage current in high-voltage insulators. The hybrid structure considers a multi-criteria optimization using tree-structured Parzen estimation, an input stage filter for signal noise attenuation combined with a large language model (LLM) applied for time series forecasting. The proposed optimized LLM outperforms state-of-the-art DL models with a root-mean-square error equal to 2.24$\times10^{-4}$ for a short-term horizon and 1.21$\times10^{-3}$ for a medium-term horizon.

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João Pedro Matos-Carvalho, Stefano Frizzo Stefenon, Valderi Reis Quietinho Leithardt, Kin-Choong Yow. 2025-02-24. Time series forecasting based on optimized LLM for fault prediction in distribution power grid insulators. https://arxiv.org/abs/2502.17341

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