【摘要】 某核电站原来#1、#2号联络变因VFTO导致变压器线圈被烧损,在新增#3联络变改造项目时,设计需充分考虑VFTO对新联络变压器的影响,避免再次发生类似事故。采用ATP电磁暂态计算程序,建立了电站中各GIS设备的电气模型,对420 kV/525 kV GIS中扩建联络变间隔内隔离开关操作引起的VFTO进行仿真计算,通过对10种典型操作方式进行计算和评估,结果表明操作隔离开关附近的过电压值最高,为2.95 p.u.,变压器入口处过电压最大为1.60 p.u.,设备的绝缘等级等参数具备承受VFTO过电压的能力。更多还原

【Abstract】 One Nuclear Pow er Station No. 3 Unit reconstruction project has improved the transformer design due to No. 1&2 Units had ever suffered failures of the interconnecting transformer coil by VFTO,so the new No. 3 interconnecting transformer should be fully considered the impact of VFTO to avoid the similar incidents. This article analyzed 10 routine operations about the VFTO impact to the equipment by using the ATP electromagnetic transient calculation program. The results show n that the overvoltage value near isolating sw itch is the highest,w hich is 2. 95 p. u.,the maximum overvoltage at the transformer entrance is 1. 60 p. u.,the insulation level of the equipment could fulfill the requirement of VFTO.更多还原