Modularized device for conversion between high-voltage direct current and direct current

Abstract

The invention discloses a modularized device for conversion between high-voltage direct current and direct current. The modularized device for conversion between the high-voltage direct current and the direct current comprises at least two direct-current-direct-current conversion modules which are the same in structure, wherein the input ends of all the direct-current-direct-current conversion modules are connected in series in sequence in the forward direction and then are arranged between a positive pole and a negative pole of a high-voltage side in a connected mode, and the output ends of all the direct-current-direct-current conversion modules are connected in series or in parallel or in a series-parallel mode according to the voltage class requirement of a low-voltage side, and then are arranged between a positive pole and a negative pole of the low-voltage side in a connected mode. Each direct-current-direct-current conversion module comprises a high-voltage side converter module, a low and medium frequency sine wave transformer and a low-voltage side converter module, wherein the output end of each high-voltage side converter module is connected with an input winding of each low and medium frequency sine wave transformer, and an output winding of each low and medium frequency sine wave transformer is connected with the input end of each low-voltage side converter module. The modularized device for conversion between the high-voltage direct current and the direct current can solve the problems of voltage resistance and voltage sharing of switching devices on the high-voltage side, improve the transmission capacity, and have a certain application prospect in places with high-voltage input high power.

Description

technical field [0001] The invention relates to a high-voltage DC-DC power conversion and transmission device, in particular to a modular high-voltage DC-DC conversion device. Background technique [0002] High-voltage direct current transmission (HVDC) has the characteristics of large transmission power capacity, low loss, long transmission distance, and good stability, and has broad application prospects. In order to adapt to the direct application of high-voltage direct current transmission to electrical equipment in the future, it is necessary to have a DC transformer device with a function similar to that of an AC isolation transformer to convert high-voltage direct current into isolated low-voltage direct current that meets the requirements of electrical equipment. [0003] Since the withstand voltage of a single power semiconductor device is usually limited, a single power semiconductor device cannot be directly applied to high-voltage applications. In order to reali...

AI Technical Summary

Problems solved by technology

However, the power capacity of currently available intermediate frequency or high frequency square wave transformers is difficult to reach hundreds of kilowatts or more, which limits the application of such DC transformers to a certain extent.

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