Average Current Mode Control of Three-Phase Boost Rectifiers with Low Harmonic Distortion Applied to Small Wind Turbines

This paper presents the application of averagecurrent mode control to reduce the THDi and increasethe PF in a Three-Phase Boost Rectifier driving asmall wind turbine. It is used as the input stage ofsmall wind turbines with permanent magnetsynchronous generators operating at variable speed.The Boost Rectifier output is connected to an inverterwhich injects the energy to a distribution power grid.The operation in discontinuous conduction modeallows significantly reducing the Total HarmonicDistortion of the current in the small wind turbine.However, it is necessary to add an input filter so thatthe switching ripple doesn´t affect the small windturbine. It is evaluated the convenience of the currentsensors placement in the DC side of the rectifier or atthe output of the generator. The results demonstratethat it is better to place the sensors at the output of thegenerator, because it is achieved a smaller THDi and ahigher PF.