HEART – The Highly Efficient And Reliable smart Transformer, a new Heart for the Electric Distribution System

Encouraged by attractive tariffs and promotion policies, the end-consumers in the local grids are not only consumers of electricity but in many cases also producers and even becoming distributed energy storage. This could result in many instances of short and long-term expectancy and emergency loadings and reverse power flows in local grids.

The current research trend in smart grids is towards an extreme-decentralization scenario as a counter-effect to the past history of extreme-centralization management of the power grid. However one of the main problems of a completely decentralized solution is the large number of data inputs, actors, control and decision-making options resulting in higher complexities and interdependencies in the architecture of these future distribution grids.

The Smart Transformer (ST) represents an automated transformer based on the latest power electronics and communication technologies. This is an excellent solution to implement a semi-decentralized control of the electric grid, where smart meters provide node information, and distributed sources and new sizeable loads are managed by a local controller embedded in the ST. This solution offers better management of the large amount of data presented in the smart grid scenario.

This project will take this challenge with a paradigm shift in how to approach it and use a new set of methodologies. The breakthrough results of this research will be obtained taking the following high-risk high-gain bet: on-line management of efficiency and reliability of the Smart Transformer through new hardware and software architectures. The ST will be modeled in terms of energy flows managed by units, formed by power electronics modules, and connected by passive elements. A new understanding of how the energy flows are managed by the ST, with respect to the requirements of the power system, will lead to new hardware architectures for the ST allowing different routes for the energy flows to be chosen on the basis of efficiency and reliability considerations. Graph theory will be used to find optimal paths for the energy flows with the goal of maximizing efficiency and minimizing the ageing of power modules, also using active thermal control based on advanced sensing of the chip temperature. The energy flows will be managed akin to Internet switched packet data, thus relying on information enclosed in packet headers. The new software architectures for the ST will switch “packets of energy” by taking into account the information traveling in the communication system and coming from the electric distribution system sensors (requirements) and from the power module sensors (constraints).