Improving the performance of power system protection using wide area monitoring systems

TLDR

Wide‑area monitoring can enhance power‑system protection, yet its effectiveness is mainly limited to backup and system protection because primary protection requires faster response, and the increasing variability, complexity, and vulnerability of modern grids make selecting suitable relay settings difficult and contribute to blackouts. This paper outlines opportunities and motivations for developing adaptive, system‑integrity protection schemes that leverage WAM to manage wide‑area disturbances beyond the capabilities of existing protection. The authors propose methods that monitor relay suitability, supervise backup protection, and implement adaptive, intelligent protection schemes, including novel system‑integrity protection. Supervising backup protection could reduce the 70 % of blackouts caused by relay maloperation, potentially preventing or limiting blackout scale.

Abstract

Wide area monitoring (WAM) offers many opportunities to improve the performance of power system protection. This paper presents some of these opportunities and the motivation for their development. This methods include monitoring the suitability of relay characteristics, supervisory control of backup protection, more adaptive and intelligent system protection and the creation of novel system integrity protection scheme. The speed of response required for primary protection means that the role WAM in enhancing protection is limited to backup and system protection. The opportunities offered by WAM for enhancing protection are attractive because of the emerging challenges faced by the modern power system protection. The increasingly variable operating conditions of power systems are making it ever more difficult to select relay characteristics that will be a suitable compromise for all loading conditions and contingencies. The maloperation of relays has contributed to the inception and evolution of 70 % of blackouts, thus the supervision of the backup protection may prove a valuable tool for preventing or limiting the scale of blackouts. The increasing interconnection and complexity of modern power systems has made them more vulnerable to wide area disturbances and this has contributed to several recent blackouts. The proper management of these wide area disturbances is beyond the scope of most of the existing protection and new, adaptive system integrity protection schemes are needed to protect power system security.