Review on wind turbine generators and power electronic converters with the grid-connection issues

This review paper focuses on the three main electrical aspects in the wind energy conversion system (WECS): 1) wind turbine generators (WTGs), 2) power electronics converters (PECs) and 3) grid-connection issues. The current state of wind turbine generators are discussed and compared in some criteria along with the trends in the current WECS market, which are `Variable Speed´, `Multi-MW´ and `Offshore´. In addition, the other crucial component in the WECS, PECs will be discussed with its topologies available in the current WECS market. Moreover, three main issues of the WECS associating with the grid-connection, fault-ride through (FRT) capability, harmonics/interharmonics emission and flicker, which are the power quality issues, will be discussed due to the increasing responsibility of WECS as utility power station. Some key findings from the review such as the attractiveness of BDFRG are presented in the conclusion of this paper.