Acceleration of distance protection second zone: A non-pilot method based on the healthy phases data

摘要

? 2022 Elsevier B.V.Nowadays, power systems are operated closer to their stability margins and therefore, the need for faster protection algorithms is escalated. The second zone of distance protection is conventionally set to operate with some lengthy delay, which increases the fault clearing time for the end part of the protected line. Therefore, the acceleration of zone-2 for internal faults can remarkably increase the speed of line protection. This practice is traditionally performed by pilot protection systems, which rely on communication channels. This paper proposes a new non-pilot solution to this challenge using only local measurements. A phasor-based algorithm is proposed to detect the remote circuit breaker operation (RCBO) using the healthy phases data. The proposed method has been developed for both single- and three-pole circuit breaker (CB) mechanisms, which makes it practical for transmission and sub-transmission lines. Thanks to using the healthy phases data, the proposed method is immune to the current transformer saturation and capacitor voltage transformer transients. The performance of the proposed method is simulated and investigated in various critical situations besides some experimental tests. The obtained results approve the efficiency and robustness of the proposed method for different scenarios, e.g. noisy conditions, evolving faults, and parallel lines.