Study On Fuse Analysis And Solution Of PT High Voltage Side Insurance In Hydropower Plant

The conventionally configured PT of the power plant is equipped with insurance on the high voltage side.Its purpose is to quickly fuse and remove the fault when the generator outlet fails,which plays a role in protecting the PT body.However,in the case of no accidents in the daily production process,PT high-voltage side fuse faults occur frequently.Through the big data statistics and analysis of the production MIS system,the main types of fuse faults include fuse and faults when the generator starts and stops There are two types of fusing during normal operation of the equipment.In this case,the generator is forced to withdraw from the system for shutdown inspection,which seriously affects production safety and production efficiency.Due to the inability to find out the cause of the failure in time,in order not to affect the production plan,many times it can only be replaced with new insurance and continue to be put into operation,thereby leaving hidden dangers.When the PT high-voltage side fuse is completely fused,the fault phenomenon is obvious,and the fault point is still easy to troubleshoot;however,when the PT high-voltage side fuse of the generator outlet is not completely fused,the fault phenomenon appears as undervoltage,which is likely to cause errors in related equipment The operation staff is helpless;the production safety is seriously affected,the production efficiency is affected,and the production cost is increased due to frequent replacement of PT high-pressure side insurance.In this paper,the influencing factors of PT high voltage side fuse are analyzed comprehensively,and the current research situation of PT high voltage side fuse at home and abroad is reviewed.Taking the fuse failure for 18 KV PT high voltage side of a hydropower plant in Southwest China as the research object,the electrical characteristics of the main electrical wiring and different operation modes are analyzed,and the fault recording data and operation records of the plant are counted and studied,the failure characteristics are summarized.Then,the steady state operation and electromagnetic transient process are analyzed,and the fault simulation model of PT high voltage side fuse is established by EMTP electromagnetic transient simulation software.Finally,the relationship between fault current and fault cause of PT high voltage side fuse is obtained by simulation,and the frequent fuse of PT high voltage side are studied and judged.In addition,the control measures and technical scheme of PT high voltage side fuse frequent fusing in the hydropower plant are put forward,which provides reference experience for completely solving PT high voltage side fuse fusing failure.