1. Electric Energy Research Center, Jeju National University, Jeju-si, South Korea
2. Department of Electrical Engineering, Jeju National University, Jeju-si, South Korea
3. Faculty of Electrical Engineering, Can Tho University, Can Tho, Viet Nam
4. Department of Electrical Engineering, Shin Ansan University, Ansan-si, South Korea
5. Korea Electrotechnology Research Institute, Changwon-si, South Korea