Data-driven Control of an LCC HVDC System for Real-time Frequency Regulation

TL;DR

This paper introduces a novel data-driven control method for LCC HVDC systems that enhances real-time frequency regulation by integrating feedback loops and a data-driven LQG regulator, validated through case studies.

Contribution

It develops a data-driven control strategy for LCC HVDC systems, combining localized feedback with an LQG regulator for improved frequency regulation in interconnected grids.

Findings

Successful frequency regulation in case studies

Enhanced cooperation between HVDC and generators

Validated models outperform physics-based models

Abstract

Recent advances in data sensing and processing technologies enable data-driven control of high-voltage direct-current (HVDC) systems for improving the operational stability of interfacing power grids. This paper proposes an optimal data-driven control strategy for an HVDC system with line-commutated converters (LCCs), wherein the dc-link voltage and current are optimally regulated at distinct HVDC terminals to improve frequency regulation (FR) in both rectifier- and inverter-side grids. Each HVDC converter is integrated with feedback loops for regulation of grid frequency and dc-link voltage in a localized manner. For optimal FR in both-side grids, a data-driven model of the HVDC-linked grids is then developed to design a data-driven linear quadratic Gaussian (LQG) regulator, which is incorporated with the converter feedback loops. Case studies on two different LCC HVDC systems are performed using the data-driven models, which are validated via comparisons with physics-based models and comprehensive MATLAB/SIMULINK models. The results of the case studies confirm that the optimal data-driven control strategy successfully exploits the fast dynamics of HVDC converters; moreover, cooperation of the HVDC system and synchronous generators in both-side grids is achieved, improving real-time FR under various HVDC system specifications, LQG parameters, and inertia emulation and droop control conditions.