Power transformers are critical in the power grid. They have a long lead time for repair and replacement. Consequently, transformer protection has to limit the damage to a faulted transformer. Some protection functions, such as over-excitation protection and temperature-based protection can identify operating conditions that may cause transformer failure.
Failures in transformers can be classified into:
- Winding failures due to short circuits (turn-turn faults, phase-phase faults, phase-ground, open winding)
- Core faults (core insulation failure, shorted laminations)
- Terminal failures (open leads, loose connections, short circuits)
- On-load tap changer failures (mechanical, electrical, short circuit, overheating)
ABB's transformer protection relays are used for protection, control, measurement and supervision of power transformers, unit and step-up transformers, including power generator-transformer blocks in utility and industry power distribution networks. The relays provide main protection for two-winding power transformers and power generator-transformer blocks.
- Flexible transformer protection relay for two-winding power transformers
- Limits the damage to a faulted transformer
- May identify operating conditions that may cause transformer failure
- Differential protection, thermal overload protection, voltage protection and automatic voltage regulator
- Configurable functionality to meet specific requirements of different applications