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arXiv · 1702.03310

Load-Flow in Multiphase Distribution Networks: Existence, Uniqueness, Non-Singularity and Linear Models

Andrey Bernstein·Cong Wang·Emiliano Dall'Anese·Jean-Yves Le Boudec·Changhong Zhao
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Abstract

This paper considers unbalanced multiphase distribution systems with generic topology and different load models, and extends the Z-bus iterative load-flow algorithm based on a fixed-point interpretation of the AC load-flow equations. Explicit conditions for existence and uniqueness of load-flow solutions are presented. These conditions also guarantee convergence of the load-flow algorithm to the unique solution. The proposed methodology is applicable to generic systems featuring (i) wye connections; (ii) ungrounded delta connections; (iii) a combination of wye-connected and delta-connected sources/loads; and, (iv) a combination of line-to-line and line-to-grounded-neutral devices at the secondary of distribution transformers. Further, a sufficient condition for the non-singularity of the load-flow Jacobian is proposed. Finally, linear load-flow models are derived, and their approximation accuracy is analyzed. Theoretical results are corroborated through experiments on IEEE test feeders.

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Andrey Bernstein, Cong Wang, Emiliano Dall'Anese, Jean-Yves Le Boudec, Changhong Zhao. 2017-02-10. Load-Flow in Multiphase Distribution Networks: Existence, Uniqueness, Non-Singularity and Linear Models. https://arxiv.org/abs/1702.03310

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