基于快速真空断路器的FCL计算分析及现场性能验证

FCL Calculation Analysis and Site Performance Verification Based on Fast Vacuum Circuit Breaker

在新疆电网局部地区,由于220 kV煤电厂增多、网架结构复杂、线路负荷增大,使系统短路电流超过了断路器的开断能力,治理短路电流超标已经成为电网公司和科研院所研究的热门课题。针对这个问题,文中首先分析了基于快速真空断路器的FCL装置原理;其次对新疆某220 kV电厂加装的2台基于快速真空断路器的故障限流器(fault-current limiter,FCL)装置,建立了稳态和暂态仿真模型,计算了稳态短路电流、快速断路器分、合闸操作过电压及其瞬态恢复电压,计算结果表明,FCL装置能有效限制短路电流,也不会对系统和设备造成危害。最后,在现场进行了FCL性能验证试验,结果表明:该FCL装置能够快速、正确动作,实现了电网限流装置结构轻便、造价低廉、运行可靠、维护方便的目标;不足之处是现场没有进行人工短路接地、系统未发生过短路故障,没有得到实测数据,有一定缺憾。

In the local areas of Xinjiang Power Grid,the increase of 220 kV coal power plants,complicated grid struc-ture and increase of line load have made the short-circuit current exceed the interruption ability of circuit breakers.Therefore,the control of short circuit current exceeds the standard has become a hot topic researched by power grid companies and research institutes.In view of this issue,the principle of FCL device based on fast vacuum circuit breaker is analyzed firstly in this paper;then,the steady and transient simulation model for two sets of FCL devices based on fast vacuum circuit breaker(VCB),which are installed at one 220 kV power plant in Xinjiang,are set up.The steady short circuit current,the opening and closed operating over-voltage of the fast circuit breaker and its transient recovery voltage are calculated.The calculation result shows that the FCL device can not only limit effectively short circuit current,but also not cause any danger to the system and equipment.Finally,the performance verification test of the FCL is performed at site.The result shows that the FCL device can be able to operate quickly and correctly and such target of the grid fault current limiter as portable structure,low cost,reliable operation and conve-nient maintenance has been achieved.However,the disadvantage is that there is no artificial short circuit grounding on site,the system has not been short circuit grounding and no actual measurement data is available,which have a definite regrets.