A fast protection scheme for VSC based multi-terminal DC grid

作者：Zou, Guibin^*; Feng, Qian; Huang, Qiang; Sun, Chenjun; Gao, Houlei

来源：International Journal of Electrical Power & Energy Systems, 2018, 98: 307-314.

DOI：10.1016/j.ijepes.2017.12.022

• Busbar protection
• Current travelling wave
• Current differential protection
• Polarity comparison
• Wavelet transform

This paper proposes a novel protection scheme for voltage source converter based multi-terminal direct current (VSC-MTDC) grid, in which DC line pilot protection applies polarity comparison of initial current travelling wave and DC busbar protection is based on sampled value current differential theory. This DC line protection utilizes modulus maximum of wavelet transform to get the polarity of initial current travelling wave on two ends of DC lines to distinguish internal faults from external faults. Current differential protection based on sampling values is adopted as DC busbar protection, which has the characteristics of fast operation speed and less computation compared to conventional current differential protection. A two-level voltage source converter (VSC) based four terminal DC grid is built on the PSCAD platform and each VSC is equipped with resistive superconducting fault current limiters (R-SFCLs) to limit the short circuit current. Thus, DC circuit breakers can be used to break the DC fault current. The simulation results verify the validity and feasibility of the proposed VSC-MTDC grid protection scheme.

• 出版日期2018-6
• 单位山东大学