Study on state-based differential protection principle and its application in feeder automation

According to current-based differential protection principle from traditional high-level electric power network, the concept of state-based differential protection principle is presented and applied to feeder automation in distribution management system in order to realize high speed fault detection, location, isolation, and restoration. The operation of the feeder automation designed upon this principle shows that a breakthrough is brought out with its much shorter restoration time from traditional more than 30 second to within 1 second. Experiment and operation data are outlined, a feeder automation solution complying with this principle is proposed.