Open Access

ARTICLE

Multi-Objective Optimization Method for Insulation Coordination of Offshore VSC-HVDC Converter Stations Considering Surge Arrester Parameter Selection

Qian Wu¹, Yuchao Zheng¹, Linyuan Wang¹, Yang Wang¹, Chenlu Mao², Bingtuan Gao^2,*
1 State Grid Jiangsu Electric Power Co., Ltd., Economic and Technical Research Institute, Nanjing, China
2 School of Electrical Engineering, Southeast University, Nanjing, China
* Corresponding Author: Bingtuan Gao. Email:

Energy Engineering https://doi.org/10.32604/ee.2026.086703

Received 04 June 2026; Accepted 23 July 2026; Published online 31 July 2026

Abstract

Reasonable insulation coordination design balancing economic cost and operational safety of equipment is particularly critical for VSC-HVDC converter stations subject to lightweight and high-integration requirements. To address the excessive margins of surge arrester parameter selection and insulation coordination in conventional engineering schemes, this paper proposes a systematic collaborative optimization method of surge arrester parameters and equipment insulation levels for offshore VSC-HVDC converter stations. Based on a typical ±400 kV offshore wind VSC-HVDC system, the surge arrester arrangement and insulation margins of the offshore VSC-HVDC converter station are presented and discussed according to the principles insulation coordination. Accordingly, a multi-objective coordinate optimization model for surge arrester parameters and equipment insulation levels is proposed, considering both life-cycle cost objective and technical objective, in which a novel transient stress index-based equivalent safety margin is introduced as the technical optimization objective. Meanwhile, an electromagnetic-transient-simulation-driven discrete multi-objective optimization solution method is adopted to obtain the optimal design scheme. Finally, a case study is carried out to verify the feasibility and effectiveness of the proposed systematic insulation coordination design methodology. Simulation results reveal that, compared with the direct-margin reference, the proposed recommended scheme improves the system-level equivalent safety margin by 7.40% and reduces the total life-cycle cost by 3.42%.

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Keywords

Offshore VSC-HVDC converter station; insulation coordination; surge arrester; equivalent safety margin; multi-objective optimization

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