MMC sub module circuit with DC-side fault blocking ability

Abstract

The invention discloses an MMC sub module circuit with a DC-side fault blocking ability, which relates to the field of power system protection control and has the advantages that short circuit current can be completely locked, the structure is simple, the needed elements are few, and integration is high. The MMC sub module circuit with a DC-side fault blocking ability comprises two half bridge sub modules, a first power switch tube with an antiparallel diode and a diode, wherein one half bridge sub module is connected with the emitter of the first power switch tube with the antiparallel diode, and the other one is connected with the collector of the first power switch tube with the antiparallel diode; the negative electrode of the diode is connected with the collector of a second power switch tube with an antiparallel diode in the half bridge sub module connected with the emitter of the first power switch tube with the antiparallel diode, and the positive electrode is connected with the emitter of a third power switch tube with an antiparallel diode in the other half bridge sub module. the product has a small size, and stability is high; the topological structure is simple, the cost is low, and realization is easy; configuration is flexible power consumption is reduced; and the DC side can be broken in the case of short cirucit, and the response is quick.

Description

technical field [0001] The invention relates to the field of power system protection and control, in particular to an MMC sub-module circuit with DC side fault blocking capability. Background technique [0002] The output voltage level of the traditional power quality comprehensive compensation device with three-phase half bridge as the main circuit is limited and the compensation ability for negative sequence current is limited, so the final compensation result cannot achieve the required effect, and its switching frequency Higher, greater loss. Sometimes in order to improve the withstand voltage of the system, it is necessary to divide the voltage in series with multiple switching devices, but this will bring problems such as the consistency of the switching devices and the voltage equalization. [0003] An invention patent application published by the State Intellectual Property Office on May 13, 2015 (application number: 201410848005X name: improved structure and isolat...

AI Technical Summary

Problems solved by technology

Its disadvantages are that the required components are diverse, the withstand voltage value is low, the DC circuit breaker has a long response time, the action frequency is high, and the loss of the components is large.

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