集成直流断路器功能的高压大容量DC/DC变换器

高压大容量DC/DC变换器是直流电网中电压变换的关键设备。提出一种集成直流断路器功能的高压大容量DC/DC变换器，利用变换器自身控制实现直流侧短路故障阻断功能，具有轻量化、低成本、高效率的优势。首先，分析该变换器的拓扑结构、工作原理，推导子模块、晶闸管、二极管等器件的参数设计依据；然后，提出闭锁子模块和晶闸管阻断故障电流的机制，设计适应于该变换器的控制方案；其次，分别针对正常工况与故障工况进行了仿真与实验验证，结果表明该变换器拓扑结构及控制策略的有效性；最后，通过与其他典型的集成直流断路器功能的DC/DC拓扑进行对比分析，评估所提变换器的技术经济性。

A High-Voltage Large-Capacity DC/DC Converter Integrated with the Function of DC Circuit Breaker

In recent years, high-voltage and large-capacity DC/DC converters have received more and more attention as the key equipment for voltage conversion in the DC grid. This paper presents a high-voltage large-capacity DC/DC converter integrated with the function of DC circuit breaker, which uses the control of the converter itself to realize the function of blocking DC-side short-circuit faults, and has the advantages of simplicity, low cost and high efficiency. At first, this paper conducts a comprehensive analysis of the topology structure and operation principles of the converter, and deduces the parameter design basis for sub-modules, thyristors, diodes and other devices. And then, the mechanism for blocking sub-modules and thyristors is proposed to block the fault current, and the control schemes of the converter are also designed. Besides, simulations and experiments are carried out for normal conditions and fault conditions, and the results have verified the effectiveness of the topology structure and control schemes. Finally, through a comparative analysis with other typical DC/DC topologies integrated with the function of DC circuit breaker, the technical and economic efficiency of the proposed converter is evaluated.