Research Of Bus-connection Sectionalized Backup Power Automatic Switching Device In The Substation

In order to limit the explosion of short circuit current in the power system,it is a simple and effective way to disconnect some line breakers or bus connection switches from the power grid.However,the reliability of the system is reduced duing to the independent operation mode of the power grid,so it is necessary to design the corresponding backup power automatic switching device.It is widely used in medium and low voltage power grid,but seldom used in 220 kV and over power grid.Especially,the application of 220 kV bus for 500 kV substation is more difficult.This paper first analyzes the function differences between the bus-connection sectionalized backup power automatic switching device and the conventional backup power automatic switching device in the 500 kV substation,and analysis the particularity of functional design which contains analog quantity,switching value,charge-discharge and start-up in bus-connection sectionalized backup power automatic switching device.Combining with the actual operating mode in 500 kV Guancheng station,the application research for bus-connection sectionalized backup power automatic switching device has been carried out in 500 kV Guancheng station,which contains device selection,detail design,field installation,logic testing and operational maintenance and other aspects.The application design scheme has been analyzed for analog quantity,switching value and two protection accessing to backup power automatic switching device.And then 18 kinds of combination connection modes of independent operation for 220 kV bus have been worked out.This paper designed four sets of online logical test scheme.Through the online test mode taking a series of action logic function test on bus-connection sectionalized backup power automatic switching device,the validity of logic function and circuit connection of 220 kV backup power automatic switching device in 500 kV Guancheng station can be verified.Analytic study has been taken on the coordination with operation and maintenance of backup power automatic switching device in 500 kV Guancheng station and other stability control devices.The example of exception handling is analyzed.This paper puts forward a n ew measure on safety pre-control of bus-connection sectionalized backup power automatic switching device in 500 kV station and analyzes the technical,economic and social benefits of bus-connection sectionalized backup power automatic switching device in 500 kV station.The research of this paper provides a better solution and technical support for solving the application on t he excessive short-circuit current level and the backup power automatic switching device in high voltage power grid.