分析了现有短路电流限制技术的发展现状,提出一种基于正温度系数(positive temperature coefficient,PTC)热敏电阻的可恢复型混合式短路限流装置的拓扑结构。通过将PTC热敏电阻与超快速分断开关并联,有效提高了限流装置的额定通流能力,并充分利用PTC材料的电阻陕速变化特性,提高装置限流能力,降低限流装置对于PTC材料额定通流要求。给出该型限流装置的检测判断原理及控制策略,分析其限流过程。完成基于PTC热敏电阻的混合式短路限流装置应用于蓄电池组电源短路限流的试验测试,通过不同设定电流值时的限流试验结果,证明所设计的装置能快速有效限制短路电流,具有良好的应用前景。
This paper analyses the developing status of existing fault current limiting technology. A topology scheme of resumable and hybrid fault current limiter based on positive temperature coefficient(PTC) thermistor is proposed. By connecting the PTC thermistor with fast breaking switch in parallel, the rating current of fault current limiter is improved effectively. Utilizing the fast changing property of the PTC material, the capability of limiting current is improved and the rating current of the PTC material is reduced. The fault detection and judgment principle and control strategy of the limiting device are developed, and the limiting process is analyzed. The hybrid fault current limiter based on PTC heat-sensitive resistance is tested with the accumulator battery source. The testing results with different setting current values have shown that the device which can limit the fault current effectively has a nice application.