Analysis Of Typical Failure Modes And Research On Reliability Improvement Strategies For Transformer Epoxy Resin Bushing

At present, the research and application of online monitoring technology for transformer epoxy bushing and transformer epoxy resin bushing mainly focus on three methods: dielectric loss factor method, frequency domain dielectric spectrum method and capacitance measurement method. The dielectric loss detection of transformer epoxy resin cast bushing is only related to the specific material of the equipment, and has nothing to do with the size and shape of epoxy bushing manufacturer, and can correctly reflect the overall degradation of the insulation configuration. The frequency domain dielectric spectrum method extends the conventional power frequency dielectric loss and capacitance measurement to the low-frequency and high-frequency bands, and uses dielectric parameters to evaluate the insulation state of the insulating material under the low-voltage sinusoidal alternating electric field with the frequency change. The capacitance detection method can effectively determine whether its capacitor screen is degraded or discharged. If the epoxy bushing for transformer capacitor screen fails during the detection process, its capacitance will show a significant increase trend. In addition to the above methods, conventional live detection methods also include insulation resistance method and the like.