Work

A Coupling‐Factor‐Based Nonlinear Decoupling Method for Transient Operation Analysis of LCL‐Filtered Grid‐Connected VSC

Year: 2025

Type: article

Abstract: ABSTRACT In light of the exponential growth in renewable energy generation, voltage source converters (VSCs) have garnered extensive attention, particularly concerning control methodologies and steady‐state operation analysis. Nevertheless, the comprehensive transient operation analysis under large disturbances remains a critical issue, owing to the challenges in the analysis and characterisation of high‐order nonlinear VSC systems. In this regard, a coupling‐factor‐based nonlinear decoupling (CFND) method is proposed in this paper. Firstly, by evaluating the correlation degree between state variables with coupling factors, the original nonlinear high‐order system can be divided into multiple decoupled first‐ or second‐order cubic modes, which can facilitate the transient stability analysis. Secondly, with the proposed CFND method, the full‐order large‐signal model of LCL‐filtered grid‐connected VSCs is created to analyse the transient stability under grid fault conditions. It is revealed that increasing phase‐locked loop (PLL) bandwidth and decreasing current loop bandwidth are unfavourable to the transient stability. Besides, decreasing the active current reference or increasing the reactive current reference is beneficial for transient stability during the low voltage ride‐through (LVRT) process. Finally, the effectiveness of the stability analysis results is verified through hardware‐in‐loop (HIL) experiments.

Source: IET Renewable Power Generation

DOI: 10.1049/rpg2.70090

Authors: Pengcheng Yang, Hongda Cai, Jing Li, Yue Li

Institution: Hangzhou City University

Language: English

Topic: Microgrid Control and Optimization

Subfield: Control and Systems Engineering

Field: Engineering

Domain: Physical Sciences

SDG: Affordable and clean energy

Open Access status: gold

Estimated APC paid: $3,500