On-line Monitoring Method of Insulation State of Dry-type Air-core Shunt Reactor Winding
Dry-type air-core shunt reactors are used for reactive power compensation and suppression of power frequency overvoltage.The number and capacity in the power grid are increasing day by day,but the accident rate is high.Among them,the ratio of interturn insulation faults is the highest,and effective online monitoring means of winding insulation state are urgently needed.The model of dry-type air-core shunt reactor was carried out by using finite element software.By analyzing the characteristics of electri-cal,magnetic and force changes of short circuit between different turns and the same turn of the winding,the development process and formation mechanism of short circuit between turns of the winding were studied,and the sensitive state variables convenient for fault mo-nitoring were explored,and an on-line monitoring method of winding insulation state based on the change rate of active power loss was proposed.The results show that the effect of the short-circuit between the different turns of the winding on the physical parameters such as electricity,magnetism and force of the reactor is greater than that of the short-circuit condition at the same position with the same turns,and the effect of the short-circuit between the different turns of the winding occurs at the end of the reactor winding is the greatest.Active power loss is sensitive to the process of reactor winding insulation fault development,and it is easy to monitor.By selecting appropriate insulation fault early warning value and insulation failure value,the state can be judged based on the change rate of active power loss,which can find reactor winding insulation fault in real time,facilitate timely measures and prevent the fault from spreading.
dry-type air-core shunt reactorwinding insulationshort circuit between different turnschange rate of active power lossonline monitoring
万方数据
维普
