Leveraging Multi-Task Learning for Multi-Label Power System Security Assessment
Muhy Eddin Za'ter, Amir Sajad, Bri-Mathias Hodge
TL;DR
This work tackles real-time power system security assessment (PSSA) by reformulating it as a multi-label classification problem solved with a multi-task learning framework. A shared conditional auto-encoder provides a common latent representation to four task-specific decoders, enabling simultaneous assessment of static, voltage, transient, and small-signal stability. Using physics-based synthetic data from the IEEE 68-bus system, the approach demonstrates improved F2-scores and robustness to unseen topologies compared with decision trees, XGBoost, and CBDAC, while offering interpretable insights into the type of insecurity. The proposed methodology reduces overfitting through cross-task regularization and adaptive weighting, and it is flexible to add or remove stability criteria, supporting practical deployment in dynamic grid environments. Limitations include assuming full PMU observability and not yet scaling to very large grids, pointing to future work in uncertainty quantification and partial observability.
Abstract
This paper introduces a novel approach to the power system security assessment using Multi-Task Learning (MTL), and reformulating the problem as a multi-label classification task. The proposed MTL framework simultaneously assesses static, voltage, transient, and small-signal stability, improving both accuracy and interpretability with respect to the most state of the art machine learning methods. It consists of a shared encoder and multiple decoders, enabling knowledge transfer between stability tasks. Experiments on the IEEE 68-bus system demonstrate a measurable superior performance of the proposed method compared to the extant state-of-the-art approaches.
