What are Gas-Insulated Line (GIL), Gas-Insulated Bus (GIB), and Gas-Insulated System (GIS)?
Gas-insulated technology is widely used in power transmission and distribution due to its compactness, reliability, and protection against environmental factors. Gas-Insulated Line (GIL), Gas-Insulated Bus (GIB), and Gas-Insulated System (GIS) are all important components in modern high-voltage power transmission and distribution systems.
1. Gas-Insulated Line (GIL)
A Gas-Insulated Line (GIL) is a transmission system that uses a combination of aluminum conductors enclosed within a tube filled with insulating gas, typically sulfur hexafluoride (SF₆) or a gas mixture (like SF₆/N₂).
Key Features of GIL:
It is used for long-distance underground or tunnel-based power transmission.
Lower transmission losses compared to overhead lines.
Resistant to external environmental factors (rain, pollution, salt deposits).
Requires less space than overhead transmission lines.
Applications of GIL:
Underground high-voltage transmission (especially in urban areas).
Connection between power plants and substations.
Tunnels, bridges, and environmentally sensitive areas where overhead lines are impractical.
2. Gas-Insulated Bus (GIB)
A Gas-Insulated Bus (GIB) is used for power transmission within substations, connecting transformers, switchgear, and other electrical components inside an enclosed SF₆-insulated system.
Key Features of GIB:
Provides a compact alternative to traditional air-insulated busbars.
Excellent insulation properties ensure minimal dielectric losses.
Protects against weather conditions, dust, and pollution.
Reduces the risk of short circuits due to external contaminants.
Applications of GIB:
High-voltage substations (especially GIS-type substations).
Power plants and industrial setups where space is limited.
Large electrical installations require high reliability.
3. Gas-Insulated System (GIS)
A Gas-Insulated System (GIS) is a complete high-voltage substation enclosed in an SF₆-insulated environment. It includes circuit breakers, disconnectors, current and voltage transformers, and busbars, all housed within a sealed gas compartment.GIS systems typically consist of components, including circuit breakers, disconnectors, and voltage transformers, insulated with gas to improve efficiency and reliability. GIS is widely used in substations and power plants to help streamline the distribution of electricity and minimize maintenance costs.
Gas-insulated technology provides high reliability, efficiency, and compact design in power transmission and distribution systems. Regular inspection, maintenance, and SF₆ monitoring ensure long-term operational safety. Gas-Insulated Line (GIL), Gas-Insulated Bus (GIB), and Gas-Insulated System (GIS) play a crucial role in modern electrical infrastructure. By utilizing gas as an insulating medium, these systems offer numerous benefits, including higher transmission capacities, reduced electrical losses, and improved reliability. As technology continues to advance, gas-insulated systems are likely to become even more prevalent in the power industry, helping to meet the growing demand for efficient and sustainable energy transmission.