132kv Grid Station

In MLCF we have two Grid stations. 1. 50MW 2. 10MW Components of Grid Station: Power transformer Bus Bars Earthing mat Switch gear Isolators (disconnectors) Circuit Breakers (VCB, SF6) Fuses Instrument Transformers (C.T, P.T.) Metering and Indicating Instruments Power Transformer: There are 3 Transformers in 132kv/6.3kv Grid. 20/26MVA (2 Transformers) 10MVA (1 Transformers) Important Points: 1. 20/26MVA refers to ONAN/ONAF, a four-letter code that indicates the cooling (IEEE C57.12.00-2000) ON-Oil Natural AN-Air Natural AF-Air Forced First letter — Internal cooling medium in contact with the windings mineral oil or synthetic insulating liquid with fire point = 300°C Second letter — Circulation mechanism for internal cooling medium:

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Transcript of 132kv Grid Station

Power Transformer:There are 3 Transformers in 132kv/6.3kv Grid. 20/26MVA (2 Transformers) 10MVA (1 Transformers)Important Points:1. 20/26MVA refers to ONAN/ONAF, a four-letter code that indicates the cooling (IEEE C57.12.00-2000)

ON-Oil NaturalAN-Air NaturalAF-Air ForcedFirst letter Internal cooling medium in contact with the windings mineral oil or synthetic insulating liquid with fire point = 300CSecond letter Circulation mechanism for internal cooling medium: N natural convection flow through cooling equipment and in Windings

Third letter External cooling medium: A airFourth letter Circulation mechanism for external cooling medium: N natural convection F forced circulation: fans (air cooling), pumps (water cooling)2. Factor:Factor at 132kv(Wapda) side is 5Factor at 6.3kv side is 100

As we know,VI (primary side) = VI (secondary side)3. Tap ChangerWe have 27 Tap positions. Tappings are on primary side.

4. Name plate data