*3.2. Energy Flows*

Campaign of measurements accurately described in [8] allows to evaluate how energy fluxes are divided between losses of the devices in each ESS, energy demands of the trains, e.g., the energy needed for traction and for on-board auxiliary loads, and the energy required by LV auxiliary loads. Moreover, these measurements have been performed considering the real number of trains in operation, variable depending on the considered day. In this way, school working days, having some hours per day characterized by ten trains in operation, no-school working days, in which five trains are in operation, and finally holidays, having just three trains on track. Additionally, also effects of the season were considered, e.g., having different contributions from heating or air conditioning systems. Results for a mid-season no-school working day, in the case of three ESSs, are in the next Table 3. Energy losses are in the range 20–24%. Further details are in [8,9].


**Table 3.** Daily energy flows for three ESSs.

1Related to the corresponding daily MV energy.

As further step, yearly consumptions have been measured, and shown in the next Table 4. The full energy consumption from MV is shared between energy demand for traction, losses and LV auxiliary loads.


**Table 4.** Annual energy demand.

How visible, annual energy losses from the transformer and its dedicated converter are about 15% of the total MV energy demand. It is therefore needed an accurate in-depth analysis of the standard transformer losses, thus evaluating the benefits given by utilization of the amorphous core transformer technology (AMT).

### **4. The Amorphous Metal Transformer (AMT)**
