35 kV开关柜电气闭锁回路设计缺陷分析与改进

Analysis and Improvement of Design Defect of Electrical Blocking Circuit in 35 kV Switch Cabinet

电气闭锁是电力系统二次回路主要闭锁方式之一,设计合理的电气闭锁可以用简单的回路实现五防逻辑,避免误操作。针对某220 k V变电站35 k VⅡ母分段柜300开关手车、进线柜302开关手车电气闭锁回路的设计缺陷进行分析,并提出了2种改进方案。经分析比较,采用了无需改动图纸和五防逻辑的方案2对300、302开关手车电气闭锁回路进行了改动,大大降低电气误操作的风险,确保了设备安全稳定运行。

Electric blocking is one of main blocking modes in secondary circuit of power system. For reasonable designed electrical blocking, simple circuit can be used to realize five-prevention logic and avoid misoperation. Design defects of electrical blocking circuit of the 35 k V II bus subsection cabinet N0.300 switch handcart and the incoming cabinet N0.302 switch handcart in a220 k V substation are analyzed. Two modification schemes are proposed. After analysis and comparison, scheme N0.2 in which drawing and five-prevention logic are no need to be changed, are used to modify electrical blocking circuits of N0.300 and N0.302 switch handcarts, which greatly reduce the electrical misoperation risk and guarantee the security and stability operation of equipment.