Converter unit and bipolar converter system

Abstract

The invention discloses a converter unit and a bipolar converter system. The converter unit comprises a control module and three power modules, the power module comprises a box body and two layers ofpower modules installed in the box body, and each layer of power module is composed of a plurality of power units arranged in cascade; a first terminal of an upper bridge arm and a first terminal of alower bridge arm are connected with alternating current on one phase in a three-phase high voltage transmission system to network a same-phase alternating current circuit; a second terminal of the upper bridge arm and a second terminal of the lower bridge arm are connected with a direct current transmission bus; the control module comprises a valve controller, and the valve controller is respectively connected with the upper bridge arms and the lower bridge arms of the three power modules to drive the power units in the upper bridge arms and the lower bridge arms to work so as to perform an electrical energy conversion operation between the three-phase alternating current and the high voltage direct current in the three-phase high voltage transmission system. Modular construction of the MMC converter valve can be realized by adopting the technical solution.

Description

technical field [0001] The invention relates to the technical field of power transmission, in particular to a converter device and a bipolar converter system. Background technique [0002] The function of the converter valve is to perform a conversion operation on the current, for example, convert AC to DC or DC to AC. Modular Multi-level Control (MMC) is a new type of voltage change circuit, which can superimpose and output high voltage by cascading multiple sub-modules. MMC converter valve has the characteristics of less output harmonics and high degree of modularization, and has broad application prospects in power systems. Considering the requirements of the converter valve on the working environment, the MMC converter valve used in the field of flexible direct current transmission usually needs to be designed as an indoor valve tower structure. However, the indoor valve tower structure has high construction requirements, high cost and long construction period. The cha...

AI Technical Summary

Problems solved by technology

Considering the requirements of the converter valve on the working environment, the MMC converter valve used in the field of flexible direct current transmission usually needs to be designed as an indoor valve tower structure. However, the indoor valve tower structure has high construction requirements, high cost and long construction period. The characteristics hinder the popularization and application of MMC converter valves

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