Large-air-gap ultralow-temperature power transformer structure

The large-air-gap ultralow-temperature power transformer structure comprises a heat insulation cavity shell used for heat insulation and magnetic conduction, the heat insulation cavity shell comprises a heat insulation cavity shell body and a flange fastened to one end side of the heat insulation cavity shell body, and a first assembly cavity is formed in the heat insulation cavity shell; the transformer primary winding assembly is arranged in the first assembling cavity; the transformer primary winding assembly is sleeved outside the heat insulation cavity shell body, the heat insulation cavity shell, the transformer primary winding assembly and the transformer secondary winding assembly are coaxially installed, and the transformer primary winding assembly and the transformer secondary winding assembly conduct magnetism through air gaps. By implementing the large-air-gap ultralow-temperature power transformer structure, a power supply can be provided for auxiliary equipment in a superconducting power transmi