Troubleshooting of three-phase transformer

In order to ensure the safe and reliable operation of the transformer, necessary inspections and tests should be carried out before operation, strict monitoring and regular maintenance should be carried out during operation, and abnormalities of the transformer should be discovered and handled in time.
Before putting into operation, new and overhauled transformers should pay special attention to checking whether the oil level of the oil storage cabinet is normal, whether the desiccant in the desiccant is damp, whether the safety airway is intact, whether the tap switch position is normal, whether the cooling device is complete, whether the control circuit is good, whether the grounding device is intact, etc.; in the test items, special attention should be paid to measuring the insulation resistance, absorption ratio and determining the connection group; in the operation monitoring, special attention should be paid to the physical quantities of the transformer, which should be within the rated range.
During the operation of the transformer, the most common faults are winding faults, core faults, and partial faults such as bushings and tap switches; according to the phenomenon of the fault, the cause should be found and the corresponding treatment method should be adopted. The following table lists the phenomenon, cause and treatment methods of common transformer faults.