Novel Region of Attraction Characterization for Control and Stabilization of Voltage Dynamics

TL;DR

This paper introduces a new, computationally efficient method for characterizing the region of attraction for voltage stability considering LTC dynamics, enabling improved online monitoring and control.

Contribution

It provides an explicit inner approximation of the ROA with reduced computational complexity and develops new optimization-based algorithms for stability monitoring and control.

Findings

The ROA characterization is computationally efficient.

The proposed algorithms are effective in a standard IEEE test system.

A quadratic and a second-order cone program are formulated for ROA and stability monitoring.

Abstract

In this paper, we study the monitoring and control of long-term voltage stability considering load tap-changer (LTC) dynamics. We show that under generic conditions, the LTC dynamics always admit a unique stable equilibrium. For the stable equilibrium, we characterize an explicit inner approximation of its region of attraction (ROA). Compared to existing results, the computational complexity of the ROA characterization is drastically reduced. A quadratically constrained linear program formulation for the ROA characterization problem is proposed. In addition, we formulate a second-order cone program for online voltage stability monitoring and control exploiting the proposed ROA characterization, along with an ADMM-based distributed algorithm to solve the problem. The efficacy of the proposed formulations and algorithms is demonstrated using a standard IEEE test system.