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The transport loss generated by a high temperature superconducting coil (HTS) in an AC transmission process will affect the operational stability of the superconducting power equipment. However, under different self-field conditions, the influence of the oscillation waveform parameters and coil structure parameters on the transport loss still needs to be clarified. This article establishes a two-dimensional axisymmetric model with a single-pancake coil with a double strip winding as the research object. For four different oscillation waveforms—sine waves, square waves, triangular waves and sawtooth waves—the influence of four variables, namely, the transmission current amplitude, the coil radius, the number of turns of the coil, and the turn-to-turn spacing of the coil, on the transport loss of HTS coils is studied in detail. The results show that under the exact parameters of the coil, for the generated transport loss, the square wave is the largest, the sine wave is the second largest, and the sawtooth and triangular wave are the smallest. Under the same self-field condition, the transport loss can be reduced by increasing the coil radius, the number of turns of the coil, and the turn-to-turn spacing of the coil, in which if the number of turns of the single-pancake coil with a double strip winding is less than 14, the transport loss can be obviously reduced by increasing the number of turns of the coil. When the number of turns exceeds 14, it does little to reduce the transport loss. Research findings can confirm the investigation of the operational stability and design of HTS coils. [ABSTRACT FROM AUTHOR]

High-temperature superconducting (HTS) coils generate local heat during the transmission of alternating current (AC), resulting in a decrease in thermal stability. The influence of relevant factors on the local heating location and temperature of the coil is still unclear. In order to strengthen the protection and operation monitoring of the superconducting coil, it is necessary to research this. Based on the H-formulation, the paper uses the electromagnetic–thermal coupling finite element method (FEM) to establish a two-dimensional (2D) axisymmetric model of the YBCO coil. The AC loss and temperature when the coil transmits alternating currents of power frequency are analyzed. Firstly, the internal temperature distribution of the coil is analyzed, and the influence of the turn number on the location of the highest temperature is discussed. For a 16-turn coil, the effects of the convective heat transfer coefficient and the thickness of the insulating layer between two turns on the magneto-caloric properties of the coil are discussed, respectively. The results show that, below 100 turns, the highest temperature of the coil occurs near the inner side; improving the heat transfer efficiency and appropriately reducing the thickness of the inter-turn insulating layer is beneficial to suppress the temperature rise and reduce the temperature difference inside the coil. The research conclusions provide a reference for the design and protection monitoring of HTS coils. [ABSTRACT FROM AUTHOR]