Transposition conductor means that a certain number of enameled copper flat wires are combined into two rows with wide surfaces contacting each other, and the upper and lower surfaces of the two rows of enameled wires are transposed in the same direction along the narrow surfaces as required. The winding of a large power transformer is composed of transposition conductors with multiple layers of electrical insulating paper tapes, which can greatly reduce the load loss, reduce the temperature rise of winding hot spots, improve the mechanical strength of the winding, and make the structure more compact and the coil processing more convenient. Therefore, once the transposed conductor comes out, it will be designed and manufactured in the windings of large power transformers.