Optimal Voltage Control Using Online Exponential Barrier Method

TL;DR

This paper introduces an online exponential barrier method for optimal voltage control in distribution systems with high renewable energy penetration, improving robustness to model inaccuracies and ensuring voltage safety.

Contribution

The paper presents a novel online exponential barrier approach that explicitly incorporates feedback and voltage constraints, with analytical guarantees and improved robustness over existing methods.

Findings

Enhanced robustness against model inaccuracies.

Proven exponential convergence rate.

Validated effectiveness on a 56-bus network.

Abstract

This paper address the optimal voltage control problem of distribution systems with high penetration of inverter-based renewable energy resources, under inaccurate model information. We propose the online exponential barrier method that explicitly leverages the online feedback from grids to enhance the robustness to model inaccuracy and incorporates the voltage constraints to maintain the safety requirements. We provide analytical results on the optimal barrier parameter selection and sufficient conditions for the safety guarantee of converged voltages. We also establish theoretical results on the exponential convergence rate with proper step-size. The effectiveness of the proposed framework is validated on a 56-bus radial network, where we significantly improve the robustness against model inaccuracy compared to existing methods.