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arXiv · 1510.07013

Fast Local Voltage Control under Limited Reactive Power: Optimality and Stability Analysis

Hao Zhu·Hao Jan Liu
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Abstract

High penetration of distributed energy resources presents several challenges and opportunities for voltage regulation in power distribution systems. A local reactive power (VAR) control framework will be developed that can fast respond to voltage mismatch and address the robustness issues of (de-)centralized approaches against communication delays and noises. Using local bus voltage measurements, the proposed gradient-projection based schemes explicitly account for the VAR limit of every bus, and are proven convergent to a surrogate centralized problem with proper parameter choices. This optimality result quantifies the capability of local VAR control without requiring any real-time communications. The proposed framework and analysis generalize earlier results on the droop VAR control design, which may suffer from under-utilization of VAR resources in order to ensure stability. Numerical tests have demonstrated the validity of our analytical results and the effectiveness of proposed approaches implemented on realistic three-phase systems.

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Hao Zhu, Hao Jan Liu. 2015-10-23. Fast Local Voltage Control under Limited Reactive Power: Optimality and Stability Analysis. https://arxiv.org/abs/1510.07013

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