Generator and Power Converter Topology For Wind Energy Conversion System

Abstract

This paper presents an overview of wind generators and power converter used in wind energy conversion systems. Renewable energies, and in particular wind energy, are taking a more and more relevant part in the generation of electric power. The incorporation of a variable speed function into a wind turbine has a variety of benefits, including: improved power yield during low wind speed conditions, reduced mechanical loading on drive train components, reduced audible noise, reduction in tower passing effects. A power electronic converter enables efficient conversion of the variable frequency output of a wind generator, driven by a variable speed wind turbine, to a fixed frequency appropriate for the grid or a load. Multilevel converters show interesting advantages in this field, such as high efficiency, low harmonic distortion and lower switching losses which is particularly useful for renewable energies, where converters usually work at these low power levels. The equal voltage cascaded multilevel converter configuration has the advantage of its modularity over the configuration of any other multilevel converter. Finally, it presents a convert topology from the simplest converters for starting up the turbine to advanced power converter topologies, where the whole power is flowing through the converter.