一种新型故障电流限制器的原理研究

Simulation study of novel fault current limiter

提出一种新型的应用柔性交流输电系统(FACTS)技术能够改善电网电能质量的故障电流限流器,其由一个固定电容器、晶闸管控制的电容器组与旁路电感并联后再和限流电感串联而成。和以往的限流器相比,其突出优点在于串联补偿功能上的改进以及用大功率自关断器件——集成门极换流晶闸管(IGCT)代替传统的门极可关断晶闸管(GTO)。正常时,通过投切不同组数的电容器,按步长的方式调整控制线路的补偿度;故障时,通过和旁路电感相串联的IGCT控制其限流程度。在详细分析其工作原理的基础上,应用Matlab程序进行了数字仿真,结果表明,该装置具有良好的性能,可有效地改善电网在故障期间的母线电压暂降问题,提高了系统的电能质量。

A novel FCL（Fauh Current Limiter） with a combined short circuit limiter and dynamic series compensator is presented. Compared with previous FCL,it has a great improvement on its series compensation. It is composed of a fixed capacitor and several banks of advanced thyristor switched capacitors which are parallel with a bypass reactor controlled by IGCT. The compensation is controlled by the capacitors＇ switching on and off in steps,while the current limitation is achieved by inserting a reactor circuit in transmission line. The good performance of this device is proved by the digital simulation using Matlab. The bus voltage sags can also be well improved during the fault due to the fast action of the FCL.