Open AccessA new pilot protection scheme for modular multi‐level converter‐based HVDC system based on voltage matching factor
Author(s) -
Ma Jing,
Xiao Zhaohang,
Li Yongli,
Zhang Jun,
Wu Bin,
Li Zhenbin,
Ma Ruichen,
Huang Weibo,
Cheng Peng
Publication year - 2022
Publication title -
iet generation, transmission and distribution
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.92
H-Index - 110
eISSN - 1751-8695
pISSN - 1751-8687
DOI - 10.1049/gtd2.12472
Subject(s) - modular design , fault (geology) , voltage , line (geometry) , control theory (sociology) , engineering , matching (statistics) , electronic engineering , computer science , electrical engineering , mathematics , statistics , operating system , geometry , control (management) , artificial intelligence , seismology , geology
Concerning the incorrect operation of line protection in modular multi‐level converter‐based multi‐terminal DC system, a pilot protection method based on voltage matching factor is proposed. First, the dynamic switching process of flexible DC converter sub‐module is analyzed, and the expression of DC voltage of converter station considering the influence of alternating current (AC) system is derived. On this basis, the model of DC line voltage considering the influence of AC injection current is built, and the equivalent DC line voltage is calculated according to the voltage model. Then, by constructing the distortion factor which reflects the difference between the equivalent DC line voltage and actual DC line voltage, the protection criterion for the identification of internal and external faults is established. Finally, simulation tests on real time laboratory (RT‐LAB) platform verify that the proposed scheme can correctly distinguish between internal and external faults in different fault cases, with fast operation speed and strong immunity to the fault resistance.