Smart grids are typically built by means of several techniques and technologies concerning poorly correlated research disciplines. Up to now, practitioners have decomposed the Smart Grid problem according to each knowledge domain, and, thus, some partial solutions have been presented so far. However, these proposals are often difficult to integrate between each other and with existing platforms due to the fact that they do not consider the Smart Grid as a whole. The purpose of this paper is to propose a simple and complete secured QoS-aware ICT architecture with self-management capabilities, provided by a cognitive system, to meet the requirements of Smart Grids. Presented experimentations show the feasibility of our solution and encourage practitioners to focus their efforts in this direction.