1. Department of Electrical EngineeringCheng Shiu UniversityKaohsiungTaiwan
2. Department of Electrical EngineeringNational Sun Yat‐Sen UniversityKaohsiungTaiwan
3. Green Energy and Environment Research Laboratories, Industrial Technology Research InstituteHsinchuTaiwan
4. Department of Marine EngineeringNational Kaohsiung Marine UniversityKaohsiungTaiwan