Constantly exploring new frontiers in technological innovation, Indiabulls Power is implementing cutting edge GIS technology for evacuation of power at its Nashik Thermal Power plant, which would ensure seamless operation besides significant economy in land use.
GAS INSULATED SWITCHGEAR
Indiabulls Realtech Ltd. - a subsidiary of Indiabulls Power Ltd. is developing a 1350 MW power project at Sinnar, Nasik district, Maharashtra. For evacuation of power from the project, the company has chosen to adopt cutting edge GIS technology for its 400 kV switchyard. GIS technology is ultra low maintenance which would ensure that the plant is able to evacuate power continuously to the grid with almost no failure, besides resulting in land saving of approx 80 Acres.
Sulphur Hexafluoride (SF6) gas insulated metal clad switchgear is called as Gas Insulated substation (GIS). In such substation, the various equipments like circuit breakers, Busbars, Isolators, CTs, PTs, earthing switches etc. are housed in the separate metal clad module filled with SF6 gas. The SF6 gas provides the phase to ground insulation. As the dielectric strength of gas is higher than air, the clearance required is smaller. Hence the overall size of each equipment and complete sub-station is reduced. The various modules are factory assembled and are filled with SF6 gas. Thereafter they are taken on site for final assembly; such sub stations are compact and can be installed at any floor of the multistory building or in the underground substation.
As the units are factory assembled, the installation time is substantially reduced. Such installation are preferred in cosmopolitan cities, industrial township, where land is very costly and higher cost of SF6 insulated switchgear is justified by saving due to reduction in floor area requirement. SF6 insulated switchgear is also preferred in heavily polluted area where dust, chemical fumes and salt layers can cause frequent flashovers in conventional outdoor substation.
Advantages of GIS
· Partitioning of functional compartments
· Completely protected encapsulation against access to hazardous part
· High Voltage parts totally independent to environmental influences
· No effect on dielectric strength by site altitude
Minimum space required
· Minimum switchgear dimensions due to SF6 insulation
· Savings in building areas up to 70% in comparison with conventional switchgear
· Maximum availability for the operator
· High degree of reliability
· Maximum system service life as independent of the environment
· Minimum maintenance requirement means extreme savings in operating costs
· Longer life time than other switchgear types leads to potential savings in new investments
· Building area and volume savings reduce the general investment and operating costs
· Flexibility towards orientation of the equipments.