The main power consumption load of the airport is the 400V equipment. Generally, 110KV transformer substation will be the core transformer substation connected with the power grid in the airport and be used for the internal power supply of the airport. Meanwhile, several 10KV switching stations, low-voltage transformer substations and generator rooms are set in all internal areas to satisfy the basic demand of partition power supply and emergency power supply switch, thus guaranteeing the safe operation of important loads of the airport. The power supply scope mainly includes terminals, parking buildings, service area, airfields and other areas. The power supply facilities with large areas are equipped with several distributed points and long circuits.