Introduction  The existing main wiring scheme for ice melting at UHVDC converter stations can only be applied to two-terminal DC systems, and the ice melting current is twice the current of the valve group. The purpose of this study is to meet the needs of using the DC operation mode for ice melting and generating a larger line ice melting current in the multi-terminal DC (MTDC) scenario. This paper conducted a design study on the main wiring scheme for ice melting of the UHVDC converter station.

  Method  A wiring scheme for ice melting of converter station that is applicable to MTDC was proposed. The scheme innovatively improved the reverse wiring of the valve group in the original ice-melting wiring scheme.

  Result  The purpose of saving equipment investment and land occupation has been achieved. The scheme can increase the ice melting current by 50% compared to the existing ice melting wiring schemes.

  Conclusion  The new ice melting wiring scheme for the converter station in this paper can effectively meet the ice-melting requirements of the UHVDC transmission line under different conditions and improve the operation economy and reliability of the transmission line.