Simultaneous voltage control and frequency oscillation damping in Hydro-Qu<acute accent>ebec's network by using an updated 735-kV shunt reactors automatic switching system

The Hydro-Que <acute accent>bec transmission system is among the most extensive and complex power grid in North America due to its very long lines (over 1000 km) joining the generation facilities in the north of the Que <acute accent>bec province to the main centers of consumption in the south. Since the 1990s, Hydro-Que <acute accent>bec has adopted a defense plan, consisting of various types of protection solutions including different remedial action schemes (RAS) and automatic action strategies, to increase the stability and reliability of its transmission system against extreme contingencies. One of these protection strategies is the automatic switching of shunt reactors (MAIS) 1 MAIS is the acronym of the French name of the project as M anoeuvre A utomatique d ' I nductance S hunt ( MAIS ). which has been in operation since 1997. The goal of the MAIS system is to keep the voltage profile of the whole 735 -kV grid in an acceptable range to increase the transmission capacity. The MAIS system at each substation is entirely independent from neighbour substations and will close or trip shunt reactors just based on local measurements. As a periodical upgrade in all existing protection solutions in the Hydro-Que <acute accent>bec power system, new functionalities have been added into the existing MAIS system to develop its new version to improve both the voltage profile and the frequency response. This paper presents this new version including the algorithm and the concept behind the new additional functionalities. The simulation results show the efficiency and performance of the proposed method. On that basis, a deployment on Hydro-Que <acute accent>bec ' s grid to replace almost all the existing MAIS system with this new version will be realized by 2030.