1. Hitachi Energy Research, ul. Pawia 7, 31-154 Kraków, Poland
2. VTT Technical Research Centre of Finland Ltd., Kivimiehentie 3, FI-02044 Espoo, Finland
3. Department of Electrical and Power Engineering, Faculty of Electrical Engineering, Automatics, Computer Science, and Biomedical Engineering, AGH University of Krakow, Al. Mickiewicza 30, 30-059 Kraków, Poland
4. Brinter, 4c Itäinen Pitkäkatu, 20520 Turku, Finland