Hierarchical Optimal Power Flow with Improved Gradient Evaluation

Heng Liang; Xinyang Zhou; Changhong Zhao

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arXiv · 2204.04827

Hierarchical Optimal Power Flow with Improved Gradient Evaluation

Heng Liang·Xinyang Zhou·Changhong Zhao

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Abstract

Existing algorithms to solve alternating-current optimal power flow (AC-OPF) often exploit linear approximations to simplify system models and accelerate computations. In this paper, we improve a recent hierarchical OPF algorithm, which rested on primal-dual gradients evaluated in a linearized distribution power flow model. Specifically, we identify a risk of voltage violation arising from the model linearization, and propose a more accurate gradient evaluation method to eliminate that risk. We further develop a hierarchical primal-dual algorithm to solve OPF based on the proposed gradient evaluation method. Numerical results on IEEE networks show that our algorithm can enhance voltage safety with satisfactory computational efficiency.

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BibTeX RIS

Heng Liang, Xinyang Zhou, Changhong Zhao. 2022-04-11. Hierarchical Optimal Power Flow with Improved Gradient Evaluation. https://arxiv.org/abs/2204.04827

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