[1] Univ West Bohemia, New Technol Res Ctr, Univ 8, Plzen 30614, Czech Republic
[2] Brno Univ Technol, Cent European Inst Technol, Future Energy & Innovat Lab, Purkynova 656-123, CZ-61600 Brno, Czech Republic
[3] Nanyang Technol Univ, Energy Res Inst NTU ERIN, Res Techno Plaza,X Frontier Block,50 Nanyang Dr, Singapore 03722, Singapore
[4] VSB Tech Univ Ostrava, Fac Elect Engn & Comp Sci, 17 Listopadu 2172-15, Ostrava 70800, Czech Republic