Keywords: harmonics, interharmonics, power quality, wind generators, distributed generation, power electronics, converters, wind turbines, wind power, wind energy, harmonic distortion
Harmonic and interharmonic distortion analysis in the grid-connected wind electric generator
The operation of wind turbines has an impact on the power quality at the connected electric network. The integration of wind electric generators with the power grid becomes a headache for power engineers in several aspects. Harmonic distortion is one of the most important phenomena which affect the grid performance. This paper provides an in-depth discussion on harmonic and interharmonic distortion taking place on the low-voltage side of the wind generator, as well as in the power grid side. A case study, to determine where a significant amount of harmonic currents or voltages exists in the system, is performed using a power quality analyser. From these measurements and subsequent calculations, the levels of harmonics and interharmonics are analysed. It is found that the harmonic distortion is invariably present on the generator side as well as on the grid side, depending on the wind turbine technology.