In this paper

the process of tracking and handling the heating of connection terminal of capacitor of the field of AC filter at an ultra-high voltage converter station is introduced

and the cause of the heating is analyzed. By analyzing the configuration and structural types of the filter of the converter station in combination with such situations as the discovery process of the heating case

site treatment and return to factory for analysis

it is finally confirmed that the heating is due to the weak contact between the lower part of the conductive rod of the capacitor outlet sleeve and the copper stranded wire and the heat is generated due to the high circuit resistance during the operation of the capacitor. In response to this

the operation and maintenance sugegstions are proposed and the maintenance suggestions are proposed and the debugging strategies of capacitor for the new station project are formulated. It has reference and guiding significance for the analysis of heat generation of capacitor with the same structure in other converter stations and substations.