Busbar protection – a review

Busbars, being one of the most critical components of a switchyard where all the power system equipments are connected, needs an important attention from protection and from reliability point of view. Any maloperation may lead to threat for system stability but instant clearance is needed during a fault to avoid cascaded tripping. Many protection schemes have been devised starting from over-current protection to differential schemes using numerical to microprocessor based analysis in recent times. The paper reviews different aspects of busbar protection schemes and the recent trends of protection and their advantages including steps taken to overcome the problems of CT saturation and ratio mismatch of CT secondary.