Print Email Facebook Twitter A non-unit line protection method for MMC-HVDC grids based on the curvatures of backward traveling waves Title A non-unit line protection method for MMC-HVDC grids based on the curvatures of backward traveling waves Author Xie, F. (TU Delft Intelligent Electrical Power Grids; Xi’an Jiaotong University) Hao, Zhiguo (Xi’an Jiaotong University) Ye, Dongmeng (Xi’an Jiaotong University) Yang, Songhao (Xi’an Jiaotong University) Li, Chuanxi (XJ Electric) Dai, Guoan (XJ Electric) Zhang, Baohui (Xi’an Jiaotong University) Wang, Ting (School of Electrical and Electronic Engineering) Date 2023 Abstract The existing protection techniques for high-voltage direct-current (HVDC) grids suffer from several shortcomings such as high sampling frequency, poor robustness, and reliance on simulation for threshold setting. To solve these problems, this paper proposes a non-unit protection method for modular multilevel converter (MMC)-based HVDC grids using the curvatures of backward traveling waves. To this end, the propagation characteristics of traveling waves and the boundary characteristics of DC lines are first studied, then the analytical expressions of backward traveling waves are derived. Moreover, the curvatures of backward traveling waves are analyzed. On this basis, a non-unit protection method is proposed, including zone selection, disturbance identification, and pole selection. At last, with a protection platform and a real-time digital simulator (RTDS) platform of the MMC-HVDC grid, the accuracy and the robustness of the proposed protection method are verified. The results show that the protection method can correctly identify faults with different distances and resistance in 1 ms and has strong robustness against transition resistance, sampling frequency, boundary value, noise, system topology, and line parameters. Subject CurvaturesHVDC gridsModular multilevel convertersNon-unit protectionTraveling waves To reference this document use: http://resolver.tudelft.nl/uuid:6ef78897-e046-4139-a145-8c9e1f056247 DOI https://doi.org/10.1016/j.ijepes.2023.109373 Embargo date 2024-01-08 ISSN 0142-0615 Source International Journal of Electrical Power & Energy Systems, 153 Part of collection Institutional Repository Document type journal article Rights © 2023 F. Xie, Zhiguo Hao, Dongmeng Ye, Songhao Yang, Chuanxi Li, Guoan Dai, Baohui Zhang, Ting Wang Files PDF 1_s2.0_S0142061523004301_main.pdf 2.58 MB Close viewer /islandora/object/uuid:6ef78897-e046-4139-a145-8c9e1f056247/datastream/OBJ/view