Hydro-Québec's defense plan: Present and future

Recent cascading failures in several power systems worldwide have highlighted the necessity to develop new automatic protection systems. Furthermore, economic and environmental considerations strictly limit the addition of new transmission lines, which implies that the more the power system develops, the more it becomes stressed. Consequently it is necessary to re-evaluate the performance of automatic protection systems in their new environment to ensure their effectiveness in order to maintain power system reliability and security. This paper presents two new Special Protection Schemes (SPSs) that will be incorporated into Hydro-Québec's current defense plan as a means to maintain its performance and satisfy all the design criteria of its future network.