The utility model discloses a looped network structure system of a transformer. The device comprises two petal type wiring annular net racks, one petal type wiring annular net rack comprises an annular shape formed by a transformer substation bus A, a section I bus in a power distribution station A and a section I bus in a power distribution station B, and the section I bus in the power distribution station A and the section I bus in the power distribution station B are provided with first bus tie switches; the other petal type wiring ring network frame comprises a ring formed by a substationbus B, a section II bus in the power distribution station A and a section II bus in the power distribution station B, and second bus tie switches are arranged on the section II bus in the power distribution station A and the section II bus in the power distribution station B; the petals are connected through a first system converter and a second system converter which are connected with each other. The architecture disclosed by the utility model can coordinate the load, eliminate the heavy load risk, improve the equipment utilization rate and improve the power supply reliability.