Full bridge type MMC direct current ice melting apparatus and control method therefor

Abstract

The invention belongs to the technical field of electric power system control and particularly relates to a full bridge type MMC direct current ice melting apparatus and a control method therefor. The apparatus comprises a circuit breaker, an isolating switch, a connecting reactor, a resonance filter-based full bridge type MMC, four ice melting knife switches and an alternating current line to be subjected to ice melting operation that are orderly connected. The method comprises a decoupling controller step, a direct current controller step and a uniform voltage modulation step. The full bridge type MMC direct current ice melting apparatus disclosed in the invention can satisfy ice melting requirements for lines of all voltage classes, and a reference basis can be provided for apparatus design. The control method put forward in the invention can provide a reference basis for control over the direct current ice melting apparatus.

Description

technical field [0001] The invention belongs to the technical field of electric power system control, and in particular relates to a full-bridge type MMC DC deicing device and a control method thereof. Background technique [0002] Among the natural disasters encountered by various power systems, ice and snow disasters are one of the most serious. Compared with other accidents, the losses caused by ice and snow disasters to the power grid are generally more serious, ranging from ice flashes to downed towers and broken lines, and even power network paralysis. [0003] At present, in order to improve the power grid's ability to resist ice and snow disasters, there are many methods and equipment for deicing and melting lines. The ice melting methods proposed at home and abroad are generally divided into four categories: thermal ice melting, mechanical deicing, natural passive deicing and other methods. Mechanical deicing is not easy to operate, and the natural passive deicing...

AI Technical Summary

Problems solved by technology

[0004] The traditional DC deicing device can achieve reactive power compensation and DC deicing mode conversion through the simple opening and closing operation of the external isolating switch, but the harmonics generated during operation are relatively large, and the response speed is slightly slow, so a large-capacity filter needs to be installed When the traditional DC ice melting device SVC is running, the voltage stress and valve loss are relatively large, and the DC ice melting and reactive power compensation device operates in the reactive power compensation mode most of the time, resulting in a greatly reduced comprehensive operating benefit

These characteristics greatly limit the application range of traditional direct current ice melting devices

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