1. Juiz de Fora Federal University, UFJF,Faculty of Engineering,Juiz de Fora,Brazil
2. Juiz de Fora Federal University, UFJF,Department of Energy,Juiz de Fora,Brazil
3. CEFET-MG,Department of Electroelectronics,Leopoldina,Brazil
4. Institute for Production Technology and Systems (IPTS), Leuphana University of Lü neburg,Lüneburg,Germany
5. Santo Antônio S.A., Hydroelectric Plant Santo Antônio,Porto Velho,Brazil