Harmonic current protection scheme for voltage source converter-based high-voltage direct current transmission system

Summary form only given. Based on the inherent characteristic of the carrier-based pulse-width modulation converters, the response of the first carrier frequency harmonic (FCFH) current in the voltage source converter (VSC)-based high-voltage direct current (HVDC) transmission system is analysed under different fault conditions in this paper. A new protection scheme for the VSC-based HVDC transmission systems is proposed based on the FCFH currents. By extracting the harmonic currents at both the endings of the DC transmission cable, the fault type can be identified. The VSC-based HVDC test system is modelled in the PSCAD/EMTDC and the proposed protection scheme is evaluated with a variety of values of the fault resistance and the fault locations. Comprehensive test studies show that the performance of the proposed protection scheme is inspiring. It can recognise the internal and the external faults correctly.