Insulation Diagnosis Technology of Capacitive Voltage Transformer Based on Secondary Voltage Change

Capacitive Voltage Transformer (CVT) is widely used in power system as a voltage measuring component. For a long time, the insulation supervision has been realized by means of uninterrupted infrared temperature measurement and periodic power failure preventive test. In this study, the relationship between common faults of capacitive voltage transformer and secondary voltage is analyzed first. On this basis, by adopting the data mining technology, only the existing EMS system data are used to make reasonable judgment strategies without increasing the hardware investment of the primary system of the power grid. The quasi-real-time on-line monitoring of CVT is realized through the change law of secondary voltage. Based on this, the faults in the running of CVT can be found in time, thus avoiding the aggravation of CVT faults, and improving the reliability of power system operation.