Work

Research on UHV AC/DC power grid's harmonic coupling characteristic under the action of geomagnetically induced currents

Year: 2025

Type: article

Abstract: Geomagnetic-induced currents (GIC) caused by geomagnetic storms (GS) can lead to transformer core saturation and harmonic generation, which further couples with harmonics from ultra-high voltage (UHV) AC/DC transmission systems, complicating grid stability. Focusing on China's UHV DC hierarchical connection mode (HCM), this study establishes a harmonic coupling model integrating GIC effects and converter-transformer interactions. A harmonic state-space (HSS) framework combined with Euler's formula simplification enables efficient analysis of harmonic propagation in multi-voltage-level grids. Simulations using PSCAD/EMTDC reveal that the harmonic content generated by the coupling of the transformer and converter is higher than that generated by the transformer alone. The superimposed coupling of cluster harmonics exceeds national standards, with 2nd harmonic currents surpassing 1 % at the AC side and 3rd harmonic voltages reaching 4.86 % in 500 kV DC links. This work provides theoretical and practical foundations for enhancing UHV grid resilience against geomagnetic disturbances.

Source: Electric Power Systems Research

DOI: 10.1016/j.epsr.2025.111652

Authors: Xinmeng Shao, Peihong Yang, Chunming Liu, Peng Li, Ruixian Wang

Institutions: Inner Mongolia University of Science and Technology, North China Electric Power University

Language: English

Topic: Power Quality and Harmonics

Subfield: Electrical and Electronic Engineering

Field: Engineering

Domain: Physical Sciences

SDGs: Industry, innovation and infrastructure, Affordable and clean energy

Open Access status: hybrid

Estimated APC paid: $2,810