Model of high-voltage switchgear for complete sets of equipment

High-voltage switchgear models include Air-Insulated (AIS), Gas-Insulated (GIS), Hybrid, and SF₆-free eco-efficient solutions, each designed for complete substation or industrial power systems.

Major Types of High-Voltage Switchgear

1. Air-Insulated Switchgear (AIS)

• Uses air as the primary insulating medium.
• Suitable for voltages from 36 kV up to 765 kV.
• Components include circuit breakers (oil, SF₆, or vacuum), disconnectors, current transformers (CTs), potential transformers (PTs), busbars, earthing switches, and protective relays .
• Advantages: Proven technology, easier maintenance, and cost-effective for outdoor installations. 2. Gas-Insulated Switchgear (GIS)
• Uses SF₆ or alternative gases for insulation.
• Compact design ideal for urban or space-constrained substations.
• Voltage range: typically 72.5 kV to 1200 kV.
• Includes integrated circuit breakers, isolators, CTs, PTs, busbars, and control panels .
• Advantages: High reliability, minimal footprint, and reduced maintenance. 3. Hybrid Switchgear
• Combines AIS and GIS technologies or integrates multifunctional products (IMP).
• Designed for quick installation and compact layouts.
• Often used in substations requiring both flexibility and high performance . 4. SF₆-Free Eco-Efficient Switchgear (e.g., EconiQ)
• Uses environmentally friendly alternatives to SF₆ gas.
• Reduces greenhouse gas emissions while maintaining high safety and reliability standards.
• Suitable for modern sustainable power networks .

Types of Circuit Breakers in High-Voltage Switchgear

• Vacuum Circuit Breaker (VCB): Arc extinguished in vacuum; suitable for medium to high voltage.
• SF₆ Circuit Breaker: Uses sulfur hexafluoride gas for insulation and arc quenching.
• Air Circuit Breaker (ACB): Uses air for arc extinction; typically for lower HV ranges.
• Oil Circuit Breaker (OCB): Uses insulating oil to quench arcs; traditional HV solution .

Key Components in Complete Switchgear Sets

• Circuit Breakers: Interrupt fault currents safely.
• Disconnectors/Isolators: Enable safe maintenance by isolating equipment.
• Current Transformers (CTs) & Potential Transformers (PTs): Measure current and voltage for protection and monitoring.
• Protective Relays: Detect faults and trigger breakers.
• Busbars: Distribute power internally.
• Earthing Switches: Safely discharge residual currents.
• Control Panels & Indicators: Provide operational monitoring and automation .

Manufacturer-Specific Models

• Hitachi Energy: Offers AIS, GIS, hybrid, and SF₆-free EconiQ switchgear up to 1200 kV AC and 1100 kV DC .
• Siemens: Provides high-voltage switchgear from 72.5 kV to 800 kV, including 3AP circuit breakers with self-compression interrupter units for reliable arc quenching .

Summary

Complete high-voltage switchgear sets are available in AIS, GIS, hybrid, and eco-efficient SF₆-free models, incorporating a full range of circuit breakers, transformers, relays, busbars, and control systems. Selection depends on voltage level, space constraints, environmental considerations, and operational requirements, with leading manufacturers offering solutions for both conventional and sustainable power networks.