RELIABLE, RESOURCE-SAVING & MAINTENANCE- FREE AIR INSULATED SUBSTATION (AIS) WITH HIGH VOLTAGE HYBRID (MIXED TECHNOLOGY) SWITCHGEAR

摘要

While designing a new Air insulated substation (AIS) or extending an existing AIS substation, the substation designers /planners increasingly faces challenges in terms of huge space requirements for building a new substation or unavailability of space for extension in an existing one, cumbersome land acquisitions process, long project completion time and an ever increasing demand for reliable and available power 24x7 from end users. While the planners have generally used full Gas insulated substation (GIS) to tackle these challenges, another technology, Hybrid Switchgear, could be a possible solution to address these challenges for AIS substation. It is steadily getting acceptable and being used in the Global & Indian power sector. The main drivers of its growth are possibility to build a techno economical AIS substation, saving on premium space, faster land clearances due to reduced space needs, quicker installation time and improved reliability and performance due to critical substation equipments being enclosed in a SF6 environment. The Hybrid switchgear, positioned in between Air insulated substation (AIS) and Gas insulated substation (GIS), contains all the switchgear functionality such as Circuit breaker/disconnector/earthing switch /current transformer etc inside SF6 gas atmosphere, while the Bus bars still remain open in the air. So this way Hybrid switchgear combines the advantages of AIS & GIS technology - GIS reliability & space saving with AIS cost advantage. IEC 62271-205 is the dedicated IEC standard for Hybrid switchgear technology and as per this standard this technology is referred as MTS (Mixed technology Switchgear).