VSC-HVDC traveling wave protection based on single-ended boundary fault information supplement strategies

Abstract

Traveling wave protection for the voltage source converter-based high-voltage direct current (VSC-HVDC) system, relying on single-ended information, has a limited ability to distinguish boundary faults. Many novel protection schemes have been proposed to enrich the single-ended fault information, with the aim of improving this ability. Nevertheless, they still face issues such as reduced protection speed or demanding protection measuring devices. To enrich the fault information within existing measurement conditions while guaranteeing the protection speed, two single-ended boundary fault information supplement strategies are proposed. According to the bipolar symmetry of the fault traveling wave, the measurement of one pole is supplemented with that of the other pole. According to the reactor characteristics, i.e., the proportional relationship between the voltage and the current change rate of the DC reactor, the voltage measurement is further supplemented. The VSC-HVDC traveling wave protection based on the single-ended boundary fault information supplement strategies is proposed. This results in a significant improvement in distinguishing high-resistance boundary faults. The protection performance and applicability have been validated on a four-terminal VSC-HVDC simulation model based on PSCAD/EMTDC.© 2017 Elsevier Inc. All rights reserved.