SF6 Circuit Breaker Solutions in High-Voltage Power Systems: A Case Study of VZIMAN Company

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1. Challenges in High-Voltage Power Systems​

1.1 High-voltage power systems, as the core of power transmission, face critical challenges:

• ​Equipment Performance Limits: With increasing voltage levels (e.g., 500kV and above), traditional circuit breakers struggle to meet high breaking capacities (over 40kA) and rapid insulation recovery requirements.
• ​Overvoltage Risks: Switching capacitive loads (e.g., capacitor banks) may cause reignition, leading to dangerous overvoltages.
• ​Poor Environmental Adaptability: Extreme climates (e.g., high humidity, condensation) accelerate equipment corrosion, shortening service life.
• ​High Maintenance Costs: Frequent inspections for traditional breakers and SF6 gas leakage risks contribute to operational inefficiency and environmental concerns.

2. VZIMAN’s Innovative SF6 Circuit Breaker Solutions​

To address these challenges, VZIMAN developed a modular SF6 circuit breaker system with core technologies:

2.1 ​Self-Energy Arc-Extinguishing Technology​

• Utilizes a single-pressure arc chamber design, where arc energy compresses SF6 gas autonomously, eliminating external pumps and reducing energy consumption.
• Employs copper-tungsten alloy contacts to withstand arc temperatures (12,000–14,000K), achieving a breaking capacity of 50kA and reignition probability below 0.1%.

2.2 Intelligent Monitoring and Environmental Optimization​

• Integrates micro-moisture and pressure sensors with ZigBee technology for real-time gas density monitoring (±0.5% accuracy).
• Uses microcrystalline alloy current transformers (0.2-class accuracy) and supports 12 CT configurations for complex protection needs.
• Implements molecular sieve and alumina adsorbents to reduce annual leakage rates (<0.5%) and HF decomposition by 90%.

2.3​ Seismic Resistance and Modular Design​

• Combines spring-operated mechanisms (CT14 type) with arc chambers for 8-degree seismic resistance and 3,000+ mechanical operations, ideal for frequent switching.
• Supports multi-break series configurations with voltage-equalizing capacitors, suitable for ultra-high-voltage systems (750kV+).

3. Performance and Competitive Advantages​

VZIMAN’s solution complies with IEC 62271-200 and demonstrates:

• ​Enhanced Reliability: 20% lower failure rates in 40.5kV systems and 85% overvoltage suppression during capacitor switching.
• ​Reduced Maintenance: Maintenance intervals extended to 10 years, with SF6 replenishment frequency reduced by 70%.
• ​Environmental Compliance: SF6 recovery rate >99%, 50% lower global warming potential (GWP), aligning with EU F-Gas regulations.

4. Typical Applications​

• ​Renewable Energy Integration: Resolves contact welding in wind farm substations caused by inrush currents during reactive compensation.
• ​Urban Grid Upgrades: Compact designs (e.g., LW8 series) fit space-constrained substations, enabling no-reignition switching for 50km unloaded lines.
• ​Cross-Border Transmission: Validated in ±800kV HVDC projects, operating reliably in -40°C environments to ensure transnational power corridor stability.