2. WHAT IS GIL
• Gas Insulated Transmission Lines (GIL) are a means for bulk
power transmission at extra high voltage (EHV).
• the first installation of GIL in 1975, second generation
GIL has been developed
• GIL is installed in combination with Gas Insulated
Switchgear (GIS), compact solutions can be delivered in
order to supply large amounts of electric power
3. DATA OF GIL
Rated voltage:
Rated current:
Transmission capacity:
Rated short-time current:
Rated Frequency:
Capacitance:
Inductance:
Resistance:
Insulation gas:
Pipe materials:
230 kV – 550 kV
2500 A – 4000 A
1000 MVA – 3800 MVA
63 kA/3s
50/60Hz
55pF/m
220nH/m
10m /km (typical)
N2-SF6 mixture
Aluminium alloys
4. LAYING METHODS OF GIL
• ABOVEGROUND INSTALLATION:
GIL installation aboveground is a trouble-free option, even for
extreme environmental conditions.
high transmission power can be achieved with above ground
installation.
5. LAYING METHODS OF GIL
• VERTICAL INSTALLATION:
Gas-insulated tubular conductors can be installed without a
problem at
any gradient, even vertically.
They can be installed in a tunnel or shaft.
6. LAYING METHODS OF GIL
• TUNNEL INSTALLATION:
they can be installed in a tunnel or shaft.
The system stays accessible for easy inspection and high
transmission capacity is ensured.
7. LAYING METHODS OF GIL
• DIRECT BURIAL:
These systems are coated with a continuous polyethylene layer.
the land can be returned to agricultural use with very minor restrictions
once
the system is completed.
8. ADVANTAGE
• GIL in tunnels has a very low environmental
impact compared to other transmission methods.
• GIL is highly efficient.
• GIL is extremely reliable.
• GIL is affordable.
• GIL emits little heat or electromagnetic radiation.
9. ADVANTAGE
• High transmission capacity.
• Low transmission losses.
• Low capacitance.
• High operational safety (no fire risk, no external impact
in
case of internal failure).
• No practical ageing of components (long
lifetime).
10. FUTURE APPLICATION
• Long Distance AC-GIL.
• TransEuropean Networks.
• Offshore Windfarms.
• Improved Reliability of Electric Power.
Supply of Cities.
