As an 11kV surge arrester supplier, I confirm these units are suitable for substations—with critical voltage-specific considerations.
1. Core Functionality
Surge arresters protect substation equipment (transformers, switchgear) from overvoltages caused by:Lightning strikes,Switching operations,Grid transients.
They divert excess current to ground, preventing insulation damage .
2. Applicability in 11kV Substation Sections
Ideal for:
- 11kV switchgear bays
- Distribution transformers (11kV windings)
- Feeder/cable terminations
Not suitable for:
- Higher-voltage sections (e.g., 24kV/36kV busbars)
- Generator step-up transformers
3. Advantages
- Cost Efficiency: Lower cost than higher-voltage arresters (e.g., 24kV/36kV), enabling multi-point protection.
- Voltage Matching: Optimized for 11kV system parameters (e.g., continuous operating voltage ≥ 9kV per IEC 60099-4).
- Targeted Protection: Mitigates typical 11kV surge profiles (e.g., 8/20μs impulses up to 40kA) .
4. Limitations & Risks
Voltage Mismatch: Using 11kV arresters on >11kV equipment risks:
- Thermal runaway during overvoltages
- Failure to clamp surges, leading to equipment damage
Inadequate Energy Handling: Higher-voltage sections require arresters with larger energy ratings (e.g., 36kV units for 36kV buses) .
5. Selection Criteria
System Voltage: Verify equipment operating voltage (must match arrester rating).
Surge Type:
- Lightning-prone sites: Prioritize high discharge capacity (>20kA).
- Switching-heavy grids: Focus on fast response time (<100ns).
Location: Coastal/industrial sites demand pollution-resistant housings (e.g., silicone rubber with creepage ≥25mm/kV) .
6. Complementary Solutions
For multi-voltage substations:
- 24kV Sections: Use 24kV Surge Arresters(rated Uc ≥ 19kV).
- 36kV Sections: Deploy 36kV Surge Arresters (energy absorption >15kJ/kV).
Conclusion
11kV surge arresters effectively protect 11kV substation equipment when voltage-matched. For mixed-voltage sites, combine with higher-rated units (24kV/36kV) for comprehensive coverage. Always validate arrester specifications against local standards (IEC/IEEE) and environmental conditions .
References
- IEC 60099-4:2014 (Surge Arrester Requirements)
- IEEE Std C62.11-2020 (Test Methods for Metal-Oxide Arresters)
- Substation Protection Guide(CIGRE Technical Brochure 584)
- GB/T 32520-2016 (EGLA Standards for AC Systems)
