Abstract-The use of a Smart Transformer-based electrical distribution could be an effective approach to reorganize the electric grid, solving the problems and challenges of distributed generation systems and active loads. While lower efficiency and higher cost compared to the conventional transformer are well known and investigated limiting factors, the required higher maintenance, related to the use of electronics systems in the electric grid, is seldom targeted. In fact, high maintenance cost would make the use of Smart Transformer inapplicable even if new services could justify higher initial cost and new semiconductor development could increase the overall efficiency. This work proposes a modular repairable system based on condition monitoring, which aims at equalizing the lifetime consumption of the single modules to make possible prognostic maintenance.