Study on the Harmonic Amplification Influence of DC Inverter Substation With Cable Outgoing Line on the Receiving-end Power Grid

The harmonic problem caused by HVDC transmission has always been the focus of the research on harmonic amplification at the receiving-end power grid. The increase in the proportion of cable lines in the receiving-end power grid makes the harmonic problem of the grid more complicated. This paper puts forward the concept of cable rate, and derives the harmonic model of the transmission line that can accurately account for the cable rate. This model can better consider the two outgoing modes of DC inverter substations. Finally, the harmonic voltage transfer coefficient model of harmonic transmission from DC system to receiving-end power grid is established, detailed research and calculations are carried out based on this model. The research results show that the influence of the cable outgoing line at the DC inverter substation on the harmonic amplification problem of the receiving-end power grid is more complicated, which is related to the cable rate, harmonic frequency, parameters of transmission line, and the mode of outgoing line at the DC inverter substation. The research results in this paper have reference significance for the cable line reconstruction of receiving-end power grid in the future.