电力系统保护与控制2025，Vol.53Issue(11)：95-104,10.DOI:10.19783/j.cnki.pspc.241195
基于差动正序分量波形相似度的海上风电低频输电线路保护方法
Protection method for offshore wind power low-frequency transmission lines based on differential positive-sequence component waveform similarity
摘要
Abstract
Fault characteristics in offshore wind power low-frequency transmission lines are significantly affected by the control strategies of power converters on both ends,making fault behavior and its impact on traditional protection schemes complex.Based on the control strategy of the converters at the two ends and the fault composite sequence network,this paper theoretically analyzes the applicability of conventional current differential protection and concludes that there is a risk of malfunction or failure to operate.Based on the characteristics of voltage and current waveforms after faults,a protection method based on the waveform similarity of the positive-sequence differential components is proposed.This method first extracts the fault components of current and voltage at the protection installation points on both sides of the line.The symmetrical component method is then used to obtain the positive-sequence components of the differential current and voltage,and the positive sequence differential voltage is corrected accordingly.Then,an improved cosine similarity measure is used to calculate the correlation between the positive sequence components of the differential current and the corrected differential voltage,while the difference in correlation is used to distinguish between internal and external faults.Finally,a PSCAD offshore low-frequency transmission system model is built,and fault scenarios with various fault locations,types,transition resistances,and sampling frequencies are analyzed.The results verify the speed and effectiveness of the proposed protection method.关键词
海上风电/低频输电系统/线路保护/对称分量法/改进余弦相似度Key words
offshore wind power/low-frequency transmission system/line protection/symmetrical component method/improved cosine similarity引用本文复制引用
高淑萍,周永宁,王晨清,陈实,宋国兵,权喆..基于差动正序分量波形相似度的海上风电低频输电线路保护方法[J].电力系统保护与控制,2025,53(11):95-104,10.基金项目
This work is supported by the General Program of Natural Science Foundation of Shaanxi Province(No.2024JC-YBMS-792). 陕西省自然科学基金面上项目资助(2024JC-YBMS-792) （No.2024JC-YBMS-792）
国家电网有限公司总部科技项目资助(52094020006U) （52094020006U）
