+86 15852255369
sales@unitatransformer.com
Oil-immersed transformers are critical components in power systems, and their stable operation directly impacts grid reliability. However, long-term use can lead to failures due to insulation aging, oil degradation, or external factors. This article explores key safety maintenance practices and common fault prevention measures to help extend equipment lifespan and minimize risks.
1. Essential Maintenance Practices for Oil-Immersed Transformers
1. Regular Insulating Oil Testing and Treatment
- Oil Quality Monitoring: Test dielectric strength, moisture content, and acid value to assess oil condition (refer to GB/T 7595 standards).
- Oil Filtration and Replacement: Use vacuum oil purifiers to remove impurities or moisture; replace severely degraded oil.
2. Temperature and Load Monitoring
- Abnormal oil temperature spikes may indicate overload or internal faults. Install real-time temperature monitoring systems with alarms (top oil temperature should typically ≤85°C).
3. Sealing Integrity Checks
- Inspect tanks, valves, and bushings for leaks to prevent air/moisture ingress, which degrades insulation.
2. Common Faults and Prevention Methods
1. Insulation Aging Failures
- Symptoms: Partial discharges, winding breakdowns.
- Prevention: Conduct regular winding resistance tests and partial discharge detection; replace aged components promptly.
2. Oil Leakage Issues
- Symptoms: Cracked tank welds, deteriorated gaskets.
- Prevention: Use oil-resistant rubber gaskets and perform annual pressure leak tests.
3. Short-Circuit and Overload Failures
- Symptoms: Sudden shutdowns, protective relay activation.
- Prevention: Install differential protection relays and avoid prolonged overloading.
3. Emergency Response Strategies
- Minor Gas Alarm: Analyze gas composition in oil samples immediately to detect internal discharges.
- Major Gas Trip: Cut power and inspect windings/core faults; never restart blindly.
Conclusion
The safe operation of oil-immersed transformers relies on routine maintenance and proactive prevention. Standardized testing, temperature control, and sealing management can significantly reduce failure rates. Companies should implement annual maintenance plans and train staff in emergency protocols.