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arXiv · 2007.03470

Convex Relaxation of AC Optimal Power Flow with Flexible Transmission Line Impedances

Yue Song·David J. Hill·Tao Liu·Tianlun Chen
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Abstract

Flexible transmission line impedances on one hand are a promising control resource for facilitating grid flexibility, but on the other hand add much complexity to the concerned optimization problems. This paper develops a convexification method for the AC optimal power flow with flexible line impedances. First, it is discovered that a flexible-impedance line is equivalent to a constant-impedance line linking a pair of transformers with correlated and continuously adjustable tap ratios. Then, with this circuit equivalent, the original optimization problem is reformulated into a semi-definite program under the existing convex relaxation framework, which improves the solution tractability and optimality in an easy-to-implement manner. The proposed method is verified by numerical tests on the IEEE 118-bus system.

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Yue Song, David J. Hill, Tao Liu, Tianlun Chen. 2020-07-07. Convex Relaxation of AC Optimal Power Flow with Flexible Transmission Line Impedances. https://doi.org/10.1109/tpwrs.2022.3164590

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