1. School of Electrical Engineering and Automation, Hefei University of TechnologyNo. 193 Tunxi RoadHeifeiPeople's Republic of China
2. National and Local Joint Engineering Laboratory for Renewable Energy Access to Grid TechnologyNo. 193 Tunxi RoadHeifeiPeople's Republic of China
3. Department of Energy TechnologyAalborg UniversityPontoppidansstrde 111, Aalborg East 9220AalborgDenmark