For protection of transformer against to overcurrent which protection is provided

For protection of transformer against to overcurrent which protection is provided

• To protect transformer we mostly proved protection against overcurrent, overvoltage, undervoltage and under frequency.
• In that most important is Overcurrent protection, we use Circuit Breaker for protection of transformer.
  

Types of Circuit breaker use for protection of Transformer

1. Air Circuit Breaker (ACB)

2. Vacuum Circuit Breaker (VCB)

3. Minimum Oil Circuit Breaker (MOCB)

4. Bulk Oil Circuit Breaker (BOCB)

5. Sulfur Hexafluoride (SF6)

6. Air Blast Circuit Breaker (ABCB)

Types of Protection of Transformer

1. Overcurrent protection (Primary Protection) : Over current induction relay is Low Voltage (L.V.) side to provided on the protect the transformer from short circuit current.
2. Overcurrent protection (Secondary Protection) : An inverse time over current induction relay is provided on High Voltage (H. V.) side for this purpose.
3. Buchholz relay : As the transformer is oil immersed, Buchholz relay is applicable to protect the transformer by providing alarms on incipient faults and trip command on very much severe faults.
4. Overload protection : A thermal relay is provided for this purpose on the secondary side of transformer.
5.  All the non current carrying metal parts are effectively grounded.

• Distance Relay
• AC Failure Detection Device
• Over-current Relay
• Mho Relay