Detection of power swing and fault occurring simultaneously with power swing using instantaneous frequency

Energy transmission lines play a more important role in power transferring from producer to consumers. Energy transmission lines should be protected from the fault and the faults should be cleared as soon as possible time. Distance relays due to their simplicity application are widely used for protection of power transmission lines. When a power swing occurs in the power system the distance relay may mal-operate during this phenomenon. In order to prevent this, the power swing blocking function is used in distance relays. In this paper, a new method based on the rate of change of the instantaneous frequency is proposed. This method has been tested practically in a standard two-area network and its applicability for detection of different types of faults is presented. One of the features of this method is low computing and simplicity in implementation, independent of network type, unnecessarily complicated setting, high impedance fault detection, and unstable power swing detection. Also, the proposed method is compared with the conventional industrial method and it has been shown that the proposed method has better performance.