Protection for 2500KVA High Tension Transformer

ABSTRACT: High tension transformers are critical and expensive components of the power system. These transformers play an important role in power delivery and integrity of the power system network. Due to the long lead time for repair and replacement of the HT transformers, there is a need of transformer protection which limits the damage to the HT transformer.HT Transformers are protected primarily against faults and overloads. The type of protection used, should minimize the time of disconnection for faults within the transformer and to reduce the risk of catastrophic failure to simplify eventual repair. Any extended operation of the transformer under abnormal condition such as faults or overloads compromises the life of the HT transformer, which means adequate protection should be provided for quicker isolation of the HT transformer under such conditions. It is necessary to choose appropriate protective device to ensure safety and reliability of the HT transformer. Circuit protection devices such as Moulded case circuit breaker and Motor protection circuit breaker protect the expensive HT transformer by rapidly disconnecting power to components in the event of abnormal operating condition. The comprehensive transformer protection is provided in this project by protective relays like pressure switch, flow switch, Buccholz relay and sensing the temperature of the HT transformer is done by PT 100 and all this is achieved with the help of digital circuitry in the control panel