Redundant looped network communication system and method for flexible direct current transmission converter valve

The invention discloses a redundant looped network communication system and method for a flexible direct current transmission converter valve. The communication system comprises a valve-level controller and a plurality of power module looped network arrays, each power module looped network array is composed of a plurality of power modules, and the valve-level controller comprises a VBC-A control system and a VBC-B control system. Each power module looped network array is an independent looped network communication subsystem and is respectively connected with the control systems VBC-A and VBC-B. The power modules of the power module looped network arrays are in communication connection through optical fibers. Each power module looped network array is internally composed of two head rings and a plurality of sub-rings, the head rings are power module combinations formed by connecting the two ends of the power module looped network array with the two control systems, and the sub-rings are power module combination