Introducing a new application philosophy for out-of-step protection

Certain shortcommings were identified in the existing method of out-of-step protection (blocking and tripping) applied in the ESKOM system in South Africa. The main purpose of this paper is to introduce a new philosophy in the application of out-of-step protection to a power system. It is believed that this method will decrease incorrect operation of the out-of-step protection and increase quality of supply to customers.