Local Adaptive Modular Protection for Transmission Systems

This paper proposes a communication-free, setting-less, and adaptive protection approach for transmission systems. The conventional protection of transmission system lines is based on distance protection and communication-assisted schemes like line differential, Permissive Over-reaching Transfer Trip, Permissive Under-reaching Transfer Trip, Direct Comparison Blocking, etc. However, the distance protection schemes are exposed to under and over-reaching issues and delayed operation for the faults on the primary line. On the other hand, communication-assisted techniques highly rely on a communication system, where a failure or cyber attack in the communication system deteriorates the performance of the protection system. To tackle these challenges, this paper presents the addition of transmission-level local adaptive modular protection (TLAMP) units to the protection system of transmission lines. TLAMP units operate in parallel with the conventional line differential and distance protection. As a backup, if communication fails to operate because of an issue in the communication system, TLAMP units can accommodate reliable fault detection and location on behalf of the protection relay. The performance of the proposed TLAMP is verified using a test transmission system simulated in PSS®CAPE.