Regular Inspection and Cleaning and Maintenance
1. External Inspection: Inspect the transformer casing, terminals, and cooling fan at least once a month to ensure they are free of deformation, rust, or looseness. If dust accumulation exceeding 2 mm is detected (refer to the "Power Transformer Operation Regulations"), clean immediately to prevent heat dissipation.
2. Internal Cleaning: During annual power outages for maintenance, use dry compressed air (pressure ≤ 0.2 MPa) to remove dust from the winding and core surfaces. Do not use damp cloths or chemical solvents to prevent damage to the insulation.
3. Fastener Inspection: Vibration may cause bolts to loosen. Retighten them every six months using a torque wrench according to the manufacturer's specifications. For example, the torque for the high-voltage side bolts of a 10kV transformer is typically 25-30 N·m (according to GB/T 1094.11).
Temperature and Humidity Control
1. Temperature Rise Monitoring: During operation, the winding temperature must not exceed 155°C (Class F insulation standard). It is recommended to install a temperature monitoring device for real-time monitoring, with the over-temperature alarm set to 130°C.
2. Humidity Management: Maintain relative humidity in the power distribution room at ≤70%. If humidity is too high, activate a dehumidifier to prevent insulation resistance from decreasing (if it falls below 1MΩ, shut down the unit for inspection; refer to IEC 60076-11).
3. Cooling System Maintenance: Clean fan filters regularly to ensure unobstructed heat dissipation. Relubricate fan bearings with grease (such as lithium-based grease) every two years, with the lubricant volume not exceeding 1/3 of the bearing cavity volume.
Insulation Performance Testing and Troubleshooting
1. Periodic Testing: Measure the winding insulation resistance (using a 2500V megohmmeter) every six months. The resistance should be ≥100MΩ (at 20°C). If the value drops by more than 50%, investigate for moisture or aging issues.
2. Partial Discharge Testing: Conduct a partial discharge test annually. The normal value is ≤10pC (according to DL/T 1631-2016). Abnormal discharge may indicate insulation cracks or contamination accumulation.
3. Emergency measures for faults: If you hear any unusual noises, burning smells, or smoke, immediately cut off the power supply and contact a professional for repair. Minor discharge sounds may indicate poor contact and you need to check the connection after turning off the power.