Innovative approach for solving dynamic voltage stability problem on the Entergy System

The Western Region of the Entergy System is limited in both generation and transmission. Past events as well as extensive voltage stability analysis had indicated that the region could be subjected to severe voltage instability. In 1998, Entergy implemented a fast acting load shedding scheme called VSHED. However, recent studies have indicated that due to increased load growth and transmission limitations in the region, the voltage instability problem could be more dynamic in nature. In order to mitigate this problem, Entergy considered implementing several existing as well as new technologies such as SVC, STATCOM, and distributed superconducting magnetic energy storage (D-SMES). Based on extensive evaluation, D-SMES proved to be the best alternative. This paper discusses the technical assessment carried out to address the voltage stability issues as well as various alternatives considered in identifying the optimal solution.