Common Faults of Transformers and Their Troubleshooting and Handling Methods

During the long-term operation of transformers, they may encounter various faults due to factors such as environmental conditions, maintenance level, and equipment aging. Timely detection and handling of faults can effectively prevent the expansion of the faults and ensure the stability of power supply. The following introduces several common transformer faults and their detection and handling methods, which can be referred to by maintenance personnel. 

One type of fault is winding failure, which is mainly manifested as aging, damage, or short circuit of the winding insulation. The main causes of the fault are prolonged overheating, insulation moisture absorption, excessive voltage, or poor wiring. During the inspection process, insulation tests and winding DC resistance tests can be conducted to determine if there is a fault in the winding. The handling methods include replacing aged insulation materials, repairing damaged parts, adjusting wiring, etc. If the fault is severe, the winding needs to be replaced. 

The second issue is core failure. Common failures include overheating of the core, loosening of the core, and damage to the core insulation. The main causes are loose core laminations, aging insulation, and excessive eddy current loss. During the troubleshooting process, faults can be identified by monitoring the core temperature and checking the core grounding condition. The solutions include tightening the core laminations, replacing damaged insulation materials, and cleaning the surface debris of the core to ensure normal magnetic conductivity and insulation performance of the core. 

The third type of fault is the oil leakage in oil-immersed transformers, which is mainly manifested as a decrease in oil level and abnormal oil color. The main causes of the fault are aging of the sealing components, damage to the oil tank, and loosening of pipeline joints. During the inspection process, it is necessary to check the oil tank, sealing components, and pipelines, and locate the leakage point. The treatment methods include replacing the aged sealing components, repairing the damaged parts of the oil tank, tightening the joints, and replenishing the transformer oil to ensure the oil level is normal. 

Fourth, the cooling system failure is manifested as excessively high transformer temperature. The main cause is the malfunction of the cooling fan, the radiator, or the blockage of the heat dissipation channels. During the inspection, check the operating status of the cooling system and clear the debris in the heat dissipation channels; the solutions include repairing or replacing the cooling fan, cleaning the radiator, and ensuring the normal operation of the cooling system. 

When troubleshooting transformer faults, the principle of "first investigation, then handling; first simplicity, then complexity" should be followed. The operation personnel must possess professional operational skills and strictly abide by the operation procedures to ensure the safety of the fault investigation and handling process.