EPFL develops medium-frequency transformer prototype


The École polytechnique fédérale de Lausanne (EPFL) has developed a medium-frequency transformer (MFT) prototype, in order to aid in the development of Solid State Transformers (SST).

An SST can perform any desired electrical energy conversion (i.e., AC-AC, AC-DC, DC-DC, DC-AC), depending on the needs of the application. This would potentially allow for the development of a DC electrical grid, rather than today’s AC grid.

The transition from AC to DC grids would require flexible, efficient and high-performance power electronic conversion devices – commonly referred to as solid-state transformers (SSTs).

The Swiss EPFL has developed a way of optimally designing and producing medium-frequency transformers (MFTs), which are one of the key enabling technologies for SSTs.

The researchers have designed, optimized and built a working MFT prototype, rated for 100kW and operated at 10kHz. Following rigorous testing, it serves as the basis for technical tutorials, some of which have already been given to various specialists from the academic and industrial worlds.

“We can be highly flexible and quickly alter the power flow – and we can do that very efficiently,” explains Marko Mogorovic, one of the device’s designers. “This will be very important when it comes to integrating the intermittent energy generation from renewable sources into tomorrow’s smart grids.”