BESS‐Based Damping Controller for Suppressing Low‐Frequency Oscillations Using LQG Control Scheme

ABSTRACT

This study proposes an advanced damping controller based on a battery energy storage system (BESS) and an optimal Linear Quadratic Gaussian (LQG) strategy to suppress low‐frequency oscillations. The design leverages a linear quadratic regulator and a Kalman filter to ensure robust performance against stochastic disturbances, measurement noise, and parameter uncertainties. To address the limitations of traditional damping methods, a rigorous comparative analysis was performed against a conventional power system stabiliser and a standard lead–lag BESS controller, both optimised via particle swarm optimisation. Simulation results across various loading conditions demonstrate that while the open‐loop system is inherently unstable, the BESS‐LQG controller provides near‐instantaneous damping, significantly suppressing the initial oscillation peaks compared to industry benchmarks. This superiority is primarily due to the controller's ability to utilise full‐state observability through its optimal observer, allowing for a more proactive and comprehensive response than traditional output‐feedback structures. The findings highlight the BESS‐LQG framework as a robust and high‐speed solution for enhancing dynamic stability in modern, high‐uncertainty power grids.