Current transformer is important electrical equipment in power systemsand is prone to insulation failure during operation.In view of small and abnormal capacitance of capacitive current transformer

it is checked throughout test

disassembly analysis that the abnormal reason is due to breakage defect at the end shield.The equivalent circuit model is set up based on the principle of insulation structure design and the suspension potential difference caused by the end shield breakage of the abnormal equipment is calculated in accordance with test situation

the influence of the end shield breakage position on the suspension potential is summarized and the effective detection method for such defect is pointed out

which has a definite reference in the analysis and treatment of the abnormal capacitance of the capacitive current transformer.