Research Of Maintenance Technology For EHV And UHV Transformers

Ultra-high voltage transformer,as one of the main equipment of transmission and distribution network,its operation safety and reliability will have a great impact on the power grid.Ultra-high voltage transformer has large volume,complex transportation process,long repairing time and wide power supply range,resulting in large loss of power grid outage.Considering the time and the cost of power outage loss,it is of great significance to carry out on-site maintenance of UHV transformer in accident,which guarantees the reliable operation and economy of UHV power grid.Therefore,it is of great practical significance to develop the application of UHV transformer maintenance technology.In this regard,based on the existing transformer on-site maintenance and factory maintenance technology,this project demonstrates and studies the related application of UHV and UHV transformer on-site factory maintenance from the aspects of maintenance platform,tooling equipment,selection of drying mode,optimization of test methods,on-site process control and so on.Firstly,aiming at the requirements of dustfall,temperature and humidity,test,tooling equipment,operation site and other functions of UHV transformer on-site maintenance technology,this paper designs and builds a factory maintenance platform which is convenient for on-site use,and lays a foundation for the future implementation of UHV large transformer on-site maintenance work.The insulation performance of transformer directly affects the life of transformer.When the transformer is repaired on site,it needs to be dried.This paper studies and demonstrates the selection of drying method for transformer body under different damage degree and different environment.For transformer products requiring on-site maintenance and review test,the no-load test and winding deformation test will be restricted by the test environment and equipment.Based on this,this paper studies and puts forward the test scheme to solve the problems of on-site no-load test and winding deformation test.Finally,according to the difference of environment and interference between the maintenance site and the factory,the technological operation requirements and corresponding quality standards such as problem checking,material storage,coil transshipment,transformer oil sample index control and test standards are studied and formulated.