1. Network operating modes

A power grid ensures the interconnection between all power generation facilities and customers. It is a highly efficient system which, if sufficiently developed, enables operators to make considerable savings. It does, however, present a number of weaknesses, which we shall endeavor to highlight below, in order to fully grasp the issues at stake in the defense plan. Indeed :

• in its transport function, its capacities are limited by problems of overloading and voltage withstand;

• in its interconnection function, it forces all power-generating units to operate in strict synchronism.