SwiSS-Transformer

An interdisciplinary R&D team develops a novel power-electronics-based transformer and analyses its application in the future electric grid.

Two low-voltage distribution grids in Rheinfelden AG (red and blue). The columns indicate the photovoltaic peak power which can be installed, if a solid-state transformer is used.

Technologies

Solid-state transformer, power electronics, silicon carbide SiC, semiconductors, energy change

Goals

Technology development for novel silicon carbide (SiC) based solid-state transformer (SST) and analysis of its application in the Swiss electric grid.

Background

In future, a large amount of electric energy will be produced by fluctuating resources such as wind and photovoltaic power plants. This imposes challenges on regional distribution grids regarding voltage stability and the load on grid components.

In contrast to conventional copper and iron-based transformers, novel power-electronics-based transformers are able to adjust dynamically electric parameters like voltage and reactive power. This way, they can stabilize local grids also under challenging conditions.

Results

The power semiconductor switches of the solid-state transformer are made of the novel semiconductor material silicon carbide (SiC). In comparison to well-established silicon semiconductors, SiC enables more compact and energy-efficient power electronic systems.

The Paul Scherrer Institute (PSI) and the École polytechnique fédérale de Lausanne (EPFL) provide technologies for fabrication and thermal management of SiC devices. At ETH Zurich, hardware and modulation concepts are developed and a SiC SST demonstrator is built.

The Institute for Electric Power Systems at FHNW coordinates the entire project and investigates innovative applications of new transformer technologies in the context of the Swiss Energy Strategy 2050 by carrying out in-depth simulations of a real distribution grid containing more than 100 transformers.

Two industry advisors, ABB Corporate Research and BKW Energie AG, support the project consortium by providing application-relevant information and by reviewing the project results.

Project information
Customer	Nationales Forschungsprogramm "Energiewende"
Execution	FHNW Institute of Electric Power Systems
Partners	ABB-Forschungszentrum, École polytechnique fédérale de Lausanne (EPFL), Paul Scherrer Institut (PSI), ETH Zürich
Duration	4 years
Funding	Schweizerischer Nationalfonds SNF
Project leader	Prof. Dr. Nicola Schulz