Single phase short circuit current can be limited by reducing number of neutral ground

avoiding auto-transformer

fast grounding switch on boosting transformer in generator-transformer unit

Y/Y/△ auto-transformer △ side open circuit

and transformer neutral point grounded by small reactance. Transformer neutral point grounded by small reactance can be done without affecting power flow in power grid and can also lower the transformer insulation requirement and building costs.Meanwhile

it can avoid breaker changing

which means heavy workload and money waste

and the key is to choose the right parameters for the small reactance. This paper comes up with the equivalent zero sequence reactance formula through theoretical derivation. Based on the formula

power system analysis software package（ PSASP） is used to calculate single phase short circuit current with different reactance parameters

and curves are used to directly show the reactance limiting effect.