Hybrid converter valve submodule topology identification method

Abstract

According to the technical scheme, the hybrid converter valve sub-module topology identification method comprises the following steps that during the charging period of a converter valve, after all sub-module control boards take energy successfully, instructions are issued to all the sub-module control boards, and sub-modules comprise full-bridge sub-modules and half-bridge sub-modules; the instruction comprises an instruction for controlling conduction of a lower IGBT device of a first bridge arm of a full-bridge sub-module and a lower IGBT device of a half-bridge sub-module; judging the type of the sub-module according to the capacitance voltage fed back by the sub-module control panel during the instruction execution period; if the capacitance voltage rising amplitude of the sub-module during the instruction execution period is greater than a threshold value, judging that the sub-module is a full-bridge sub-module; and if the rising amplitude of the capacitor voltage of the sub-module is smaller than the threshold value during instruction execution, the sub-module is judged to be a half-bridge sub-module. The method solves the problems that manual identification of the topological structure of the sub-module is unreliable and the workload is large.

Description

technical field [0001] The invention belongs to the technical field of flexible direct current power transmission, and particularly relates to a topology identification method for a sub-module of a hybrid converter valve. Background technique [0002] In recent years, flexible DC transmission technology has become an indispensable technology to support large-scale renewable energy consumption, energy Internet construction and energy transformation. Has unique advantages. In the future, flexible DC transmission technology will develop towards higher performance and more compact equipment and system design, and will become an important technical support for promoting large-scale development and utilization of new energy and power grid construction. [0003] Most of the flexible DC projects that have been put into operation so far use such as Picture 1-1 The modular multi-level converter valve is formed by cascading the half-bridge sub-modules. The half-bridge sub-module inc...

AI Technical Summary

Problems solved by technology

However, due to the limitations of the valve tower structure and electrical structure, the sub-modules of the full bridge and half bridge are usually scattered in the project. It is necessary to test each module individually during the commissioning stage of the sub-system in the station to identify the specific topology and then press the fixed value. written in the form of the device, this method is time-consuming and labor-intensive

At the same time, if there is a module topology identification error, it will cause the charging and discharging circuit of the sub-module to be inconsistent with the program's predetermined target, the capacitor voltage of the bridge arm will be unbalanced, the over-voltage protection or under-voltage protection will operate, and at least it will cause unlocking failure or tripping. If it is serious, it will cause the module to explode, and the fire alarm in the valve hall will be activated

Images