Hybrid gas-insulated switchgear (HGIS) consists of high-voltage switching systems that combine elements of air insulation (AIS) and gas insulation (GIS) technology. This approach provides the compactness and high reliability of GIS equipment while maintaining the flexibility and affordability of traditional air-insulated components.

HGIS systems are used in medium- and high-voltage substations where compactness, reduced installation space, high resistance to climatic conditions, and minimal operating costs are important.

Purpose of HGIS

Switching and protection of high-voltage power lines.

Operation in 72.5–420 kV substations.

Reduced installation footprint compared to AIS.

Increased reliability and reduced risk of accidents.

Integration into modernized and reconstructed power facilities.

Use in industrial, urban, and inter-system nodes.

Minimum and maximum technical specifications (general ranges)

Voltage class: 72.5 kV, 110 kV, 145 kV, 170 kV, 245 kV, 363–420 kV (confirmed by images from Dowei Electric, Rockwill, Boerstn — )

Break capacity: 20–40 kA (typical values for high-voltage circuit breakers in HGIS systems)

Rated current: 1,250–3,150 A (depending on the series and voltage class)

Design types:

modular HGIS (circuit breaker + disconnector + earthing switch + current transformers);

porcelain and polymer insulators;

SF₆ insulation in circuit breakers and key components;

outdoor and indoor installation.

Gas system: SF₆ at a pressure of 0.4–0.8 MPa (typical for GIS/HGIS equipment)

Installation: open-type substations, compact switchgear, and retrofits of existing AIS units.

Resistance: to UV radiation, contamination, low temperatures, and vibrations.

What We Can Supply and Provide

We supply HGIS units of any brand—we select the optimal solution based on the facility’s technical requirements.

We design high-voltage switching stations, integrating HGIS into substation layouts.

We perform configuration, installation, commissioning, and maintenance.

We provide a warranty covering all stages—from equipment selection to commissioning.

Warranties and Liability

We ensure that the equipment complies with international standards, monitor the quality of deliveries, and guarantee the stable operation of HGIS within high-voltage systems. Each stage is backed by an official warranty and technical support.