Presence of defects, conducting particles, nonconducting particles, and nitrogen gas bubbles in the insulation system of high-temperature superconducting (HTS) transformers, mainly inside the liquid nitrogen as its major insulation, can create local field enhancement and consequently partial discharges which eventually lead to the catastrophic failure of the transformer. In this paper, two-dimensional (2D) axisymmetric finite element method (FEM) modeling via COMSOL Multiphysics software has been utilized for the investigation of the impact of size and shape of conducting particles and nitrogen gas bubbles on partial discharge (PD) activities in liquid nitrogen. Conducting particles of various shapes and the nitrogen bubbles are studied for PD generation. The results have been analyzed and compared. This can be employed for HTS transformer efficiently and PD free insulation design to enhance its insulation life.

高温超导（HTS）变压器的绝缘系统中主要存在液态氮作为其主要绝缘层的缺陷，导电颗粒，非导电颗粒和氮气气泡的存在会导致局部电场增强，从而导致局部放电，最终导致导致变压器的灾难性故障。本文通过COMSOL Multiphysics软件对二维（2D）轴对称有限元（FEM）建模进行了研究，研究了导电颗粒和氮气气泡的尺寸和形状对局部放电（PD）活动的影响。液氮。研究了各种形状的导电颗粒和氮气泡以产生PD。结果进行了分析和比较。