Multi-functional direct current ice melting automatic switching circuit and switching method thereof

Abstract

A multi-functional automatic switching circuit for direct current ice melting and a switching method thereof are provided. The automatic switching circuit comprises at least one sub-switching circuit. The sub-switching circuit comprises a six-pulse current converter (R) with no saturable reactor, six reactors (L, L, L, L, L, and L), three three-phase knife switches (Sac, Sac, and Sac), and five single-phase knife switches (SV, SV, SV, SV, and SV). The sub-switching circuits in series connection or parallel connection, four direct current side switching knife switches (Sdc, Sdc, Sdc, and Sdc), an isolation knife switch (K), a breaker (QF) and a control and protection system (CP) may form an automatic switching circuit for six-pulse or twelve-pulse direct current ice melting. The automatic switching circuit with no saturable reactor reduces noise during operation, achieves mutually automatic switching among modes of reactor switching, ice melting and test, and may complete the through-flow test of the automatic switching circuit without switching in a power transmission line, thereby solving the problem of daily operation and maintenance.