宽禁带半导体高速固态断路器及其在低压直流配电网中的应用研究

DC solid-state circuit breakers are an indispensable component to protect against short circuit faults, and ensure safe and stable operation of DC power systems. Silicon-based solid-state circuit breakers (SSCB) have the disadvantages of slow response time, high conduction loss, and complex system design. A self-powered and fast-speed 400-1000V DC solid-state circuit breaker based on normally-on wide band-gap (WBG) power semiconductor switches will be studied in the project. It takes full advantage of WBG semiconductors and can substantially reduce the conduction loss when the distribution system operates normally. When a short circuit fault occurs, it can respond within a few microseconds by detecting the voltage drop on the power switch and subsequently activate the shut-down circuit using the power drawn from the fault condition itself. First, the electrical model of the DC distribution system of different grounding modes is to be established, and the feature and regularity of distribution of fault current will be found. Second, the topology and device structure of WBG semiconductor solid state circuit breaker, will be developed to meet the protection requirements for different types of circuit faults. Finally, the safe operating area (SOA) of WBG semiconductors, the relationship between electro-thermal effect and over-current ability and its analysis method are to be studied. The project will facilitate the protection the DC distribution system in the short circuit situation and the development of DC distribution technology and power electronic science.

直流固态断路器是直流配电系统中隔离短路故障的必要手段，是低压直流配电网安全稳定运行的重要保障。但基于硅功率器件的直流固态断路器存在反应速度慢、通态损耗高等问题。本项目拟研究一种基于常通型宽禁带半导体器件的自供电、超快速反应的400-1000伏直流固态断路器。当电路处于正常导通状态时，充分发挥宽禁带半导体器件的优势，大幅降低断路器的通态损耗；当出现短路故障时，通过检测功率器件上的压降来鉴别故障的发生，将固态断路器的响应速度大幅度降为微秒级。项目首先建立不同接地方式下及分布式电源接入时直流配网的电气模型，揭示故障电流特征及分布规律；结合不同故障类型保护需求，提出宽禁带半导体固态断路器拓扑结构及自供电驱动电路；研究宽禁带半导体器件安全运行区及电热效应对过流能力的影响机理及量化分析方法。本项目将为实现直流配电网中短路电流保护问题的解决提供有效途径，促进直流配电技术的进步及电力电子学科的发展。

直流固态断路器是直流配电系统中隔离短路故障的必要手段，是低压直流配电网安全稳定运行的重要保障。但基于硅功率器件的直流固态断路器存在反应速度慢、通态损耗高等问题。本项目拟研究一种基于常通型宽禁带半导体器件的自供电、超快速反应的400-1000伏直流固态断路器。当电路处于正常导通状态时，充分发挥宽禁带半导体器件的优势，大幅降低断路器的通态损耗；当出现短路故障时，通过检测功率器件上的压降来鉴别故障的发生，将固态断路器的响应速度大幅度降为微秒级。项目首先建立不同接地方式下及分布式电源接入时直流配网的电气模型，揭示故障电流特征及分布规律；结合不同故障类型保护需求，提出宽禁带半导体固态断路器拓扑结构及自供电驱动电路；研究宽禁带半导体器件安全运行区及电热效应对过流能力的影响机理及量化分析方法。本项目将为实现直流配电网中短路电流保护问题的解决提供有效途径，促进直流配电技术的进步及电力电子学科的发展。