An Online Network Model-Free Wide-Area Voltage Control Method Using PMUs

TL;DR

This paper introduces a real-time, model-free wide-area voltage control method using PMU data that adapts to network changes and noise, enhancing voltage stability without requiring detailed system models.

Contribution

It develops an online sensitivity estimation approach based on Ornstein-Uhlenbeck process regression, enabling effective voltage regulation without full system knowledge.

Findings

Effective voltage control demonstrated on IEEE test systems.

Robust performance under measurement noise and missing PMUs.

Outperforms model-based methods during topology changes.

Abstract

This paper proposes a novel online measurement-based Wide-Area Voltage Control (WAVC) method using Phasor Measurement Unit (PMU) data in power systems with Flexible AC Transmission System (FACTS) devices. As opposed to previous WAVC methods, the proposed WAVC does not require any model knowledge or the participation of all buses and considers both active and reactive power perturbations. Specifically, the proposed WAVC method exploits the regression theorem of the Ornstein-Uhlenbeck process to estimate the sensitivity matrices through PMU data online, which are further used to design and apply the voltage regulation by updating the reference points of FACTS devices. Numerical results on the IEEE 39- Bus and IEEE 68-Bus systems demonstrate that the proposed model-free WAVC can provide effective voltage control in various network topologies, different combinations of voltage-controlled and voltage-uncontrolled buses, under measurement noise, and in case of missing PMUs. Particularly, the proposed WAVC algorithm may outperform the model-based WAVC when an undetected topology change happens.