With the development of power system

the medium voltage side of the autotransformer reactance is very close to zero

leading to fault ride through current is close to or even exceed the transformer can withstand short circuit current limit value when nearly single-phase or two-phase grounding transformer 220 kV side

to restrict Luoping Substation 220 kV single phase or two phase short circuit current level

improve the main transformer running environment

in main transformer neutral point reactor with current limit. Using the latest EMTPE program

the electromagnetic transient characteristics of the main transformer

such as the level of the main transformer current

overvoltage

insulation and so on

are studied. It is put forward that the 500 kV main transformer neutral point Luoping Substation current-limiting reactor impedance selection principle

current-limiting effect

power frequency and switching overvoltage level

steady state and transient current level on the neutral point reactor of main transformer

the main transformer neutral arrester and current limiting reactor technology parameters are determined. By means of the transformation

it can significantly reduce the level of 220 kV single or two phases short-circuit current in Luoping Substation

and improve the operating condition of the main transformer.