Distributed Primary Frequency Control through Multi-Terminal HVDC Transmission Systems

TL;DR

This paper introduces a decentralized control method for sharing primary frequency reserves across interconnected AC and HVDC grids, ensuring stability and bounded control errors, validated through simulation on a multi-terminal HVDC test system.

Contribution

It proposes a novel decentralized controller for multi-terminal HVDC systems that guarantees stability and quantifies control errors, advancing frequency control strategies.

Findings

Controller stabilizes the interconnected AC-HVDC system.

Control errors are bounded and analyzed.

Simulation confirms effectiveness of the proposed method.

Abstract

This paper presents a decentralized controller for sharing primary AC frequency control reserves through a multi-terminal HVDC grid. By using Lyapunov arguments, the proposed controller is shown to stabilize the equilibrium of the closed-loop system consisting of the interconnected AC and HVDC grids, given any positive controller gains. The static control errors resulting from the proportional controller are quantified and bounded by analyzing the equilibrium of the closed-loop system. The proposed controller is applied to a test grid consisting of three asynchronous AC areas interconnected by an HVDC grid, and its effectiveness is validated through simulation.