1. State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources
2. North China Electric Power University
3. Beijing 102206
4. P. R. China
5. Beijing Key Laboratory of Novel Thin-Film Solar Cells
6. Energy System Engineering Department
7. NAAM Research Group
8. Department of Mathematics
9. Faculty of Science
10. King Abdulaziz University
11. Jeddah 21589