Nekrasov, Alexey, <p>1. Saint Petersburg Electrotechnical University, Professora Popova 5, 197376 Saint Petersburg, Russia;</p><p>2. Southern Federal University, Chekhova 2, 347922 Taganrog, Russia;</p><p>3. Technical University of Košice, Rampová 7, 041 21 Košice, Slovaki, Russian Federation