1. Department of Ship Electrical Power Engineering, Gdynia Maritime University, 81-87 Morska St., Gdynia, Poland
2. Department of Ship Automation, Gdynia Maritime University, 81-87 Morska St., Gdynia, Poland
3. Research and Development Centre for Electrical Machines, Zakład Maszyn Elektrycznych “EMIT” Cantoni Group, Narutowicza St. 72, Żychlin, Poland