1. Department of Electrical Engineering and Information Technology (DIETI), University of Napoli – Federico II, Naples, Italy
2. Department of Renewable Energy and Vehicular Technology Laboratory (REVT), University of Texas at Dallas, Richardson, TX, USA
3. National Renewable Energy Laboratory, Golden, CO, USA
4. Nidec ASI s.p.a., Cinisello Balsamo (MI), Italy
5. Power Electronics and Electric Power Systems Research Center, Oak Ridge National Laboratory (ORNL), Oak Ridge, TN, USA