Half-bridge MMC sub-module topological structure

Abstract

The invention provides a half-bridge MMC sub-module topological structure. The half-bridge MMC sub-module topological structure comprises a half-bridge sub-module and a mirror image sub-module, the negative electrode end of the half-bridge sub-module is connected with a positive electrode end of the mirror image sub-module, the positive electrode end of the half-bridge sub-module forms the positive electrode end of the MMC sub-module, and the negative electrode end of the mirror image sub-module forms the negative electrode end of the MMC sub-module. According to the invention, the bypass module, the energy taking module and the control module can adjust the volume, weight and economy of the MMC sub-module; an input unit in the energy taking module is connected in parallel with the first direct-current capacitor C1 and the second direct-current capacitor C2; the invention is used for realizing complete redundancy of an input unit. The control module can still have a long-time and complete control protection capability when the half-bridge sub-module and the mirror image sub-module have a single fault; the possibility of bridge arm open circuit of the modular multilevel converter orlockout tripping of the flexible direct-current power transmission system is greatly reduced, the probability of bridge arm short circuit of the converter valve or lockout tripping of the flexible direct-current power transmission system is further reduced, and the reliability of the converter valve is improved.

Description

technical field [0001] The invention relates to the technical field of power systems, in particular to a half-bridge MMC sub-module topology. Background technique [0002] The modular multilevel converter (MMC) has become the preferred converter topology for flexible direct current transmission systems, among which the half-bridge-based modular multilevel converter is the most widely used in existing commissioning projects with maturity. [0003] The sub-modules used for modular multilevel converters in the prior art can be divided into half H-bridge type sub-modules, full H-bridge type sub-modules and double-clamp type sub-module type sub-modules according to the structure. After the modular multi-level converter is powered on as a whole, the operation information of individual sub-modules in the modular multi-level converter cannot be obtained by the control system, and the sub-modules whose operation information cannot be obtained by the control system have power device ...

AI Technical Summary

Problems solved by technology

After the modular multi-level converter is powered on as a whole, the operation information of individual sub-modules in the modular multi-level converter cannot be obtained by the control system, and the sub-modules whose operation information cannot be obtained by the control system have power device explosions The possibility of refusal to move the bypass switch and the bypass switch may easily lead to bridge arm open circuit in the modular multilevel converter and latching trip of the flexible direct current transmission system

And the current sub-modules have great limitations in terms of light weight, miniaturization and economy

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