An abnormal noise was detected in phase A of the 35 kV No.1 capacitor bank′s series-connected reactor at a 330 kV substation.Various live tests are conducted to accurately determine the operational status of Phase A of this 35 kV No.1 capacitor bank′s series-connected reactor

including infrared temperature measurements

partial discharge

assessments

acoustic imaging

related to insulation or overheating were detected.After disconnecting the power

tests on inductance

DC resistance

and interturn overvoltage were conducted.The comprehensive analysis

in conjunction with the results of acoustic imaging

determines that the abnormal noise originated from within the glass-fiber-reinforced plastic pillar.After disassembly

it was discovered that the pillar′s grounding lead wire was found to be in contact with the wall of the pillar

causing vibration and abnormal noise during operation.This study provides valuable data support for anomaly diagnosis by integrating the live detection and insulation test.