直流断路器半导体组件内母排电感对并联IGBT关断特性的影响及其结构优化

大功率绝缘栅双极晶体管(insulated gate bipolar transistor,IGBT)混合式高压直流断路器是适应多端柔性直流输电工程发展的关键装备,优化断路器半导体组件内IGBT故障大电流的关断特性进而确保器件安全可靠运行是断路器工程的重要部分。文章围绕组件内杂散电感对IGBT关断瞬态电压峰值、关断损耗和并联IGBT间关断动态均压、均流特性的影响,对组件的母排结构进行了优化设计。通过实验和仿真对比研究可得:采用将2组缓冲RCD分散、对称布置于并联IGBT两侧的方式设计的母排结构可更大程度优化并联IGBT的关断瞬态特性,但采用将单组缓冲RCD布置于并联IGBT中间的方式可在满足器件安全可靠运行条件的同时提高经济性,更适合工程应用。该研究结论可为基于并联IGBT的直流断路器组件中母排结构设计及优化提供技术指导。

Influence of Stray Inductance in the Semiconductor Module of DC Circuit Breaker on Turn-off Characteristics of Parallel IGBTs and Optimization Design of Busbar Structure

High voltage DC circuit breaker based on IGBT, a key equipment for the multi-terminal flexible HVDC transmission engineering, is an important parts of circuit breaker engineering, which is able to optimize the high current turn-off characteristics of IGBTs in semiconductor module of the circuit breaker and then ensure the safe and reliable operation of the devices in the system. Aiming at the influence of stray inductance in the module on the transient turn-off voltage, the loss of IGBTs and the dynamic voltage/current balance of parallel IGBTs, the optimization design for the busbar structure is conducted in this paper. Through experimental and simulation comparison studies, the busbar structure designed by arranging two sets of RCD on both sides of the parallel IGBTs can optimize the turn-off transient characteristics of the parallel IGBTs to a greater extent. However, the method of arranging one set of RCD in the middle of the parallel IGBTs can improve the economy on the basis of meeting the safe and reliable operating conditions of the devices, and is more suitable for engineering applications. The conclusions in this paper can provide technical guidance for the design and optimization of the busbar structure in DC circuit breaker modules with parallel IGBTs.