High Voltage Switchgear
The power system deals with voltage above 36KV, is referred as high voltage switchgear. As the voltage level is high the arcing produced during switching operation is also very high. So, special care is to be taken during designing of high voltage switchgear. High voltage circuit breaker, is the main component of HV Switchgear
, hence high voltage circuit breaker (CB) should have special features for safe and reliable operation. Faulty tripping and switching operation of high voltage circuit are very rare. Most of the time these circuit breakers remain, at ON condition, and may be operated after a long period of time. So CBs must be reliable enough to ensure safe operation, as when required. High voltage circuit breaker technology has changed radically in the last 15 years. Minimum oil circuit breaker (MOCB), air blast circuit breaker and SF6 circuit breaker are mostly used for high voltage switchgear.
High voltage switchgears are categorized as,
1.Gas insulated indoor type (GIS),
2.Air insulated outdoor type.
Again, outdoor type air insulated circuit breakers are classified as, 1.Dead tank type circuit breaker
2.Live tank type circuit breaker