A Wide Area Relaying Protection Algorithm Based on Longitudinal Comparison Principle

A wide area relaying protection algorithm based on longitudinal comparison principle is proposed. Wide area relaying protection system collects fault direction information from protection intelligent electronic devices (IEDs) in specific protection zone, and estimates fault site based on protection Action Factor (AF) and Relationship Factor (RF) that are defined in this paper. The N-1 operation statuses in relaying protection system is defined by benefiting from the N-1 concept in power system analysis field. The relaying protection N-1 operation statuses are analyzed and the strategies to reduce influences caused by N-1 operation statuses based on wide area information are proposed. The results of case study show that the wide area relaying protection algorithm based on longitudinal comparison principle is simple and convenient for fault determination, the fault estimation results are exact and immune against N-1 operation statuses, which can improve the performance of relaying protection system markedly.