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

Abstract

This paper presents the application of average current mode control to reduce the THD i and increase the PF in a Three-Phase Boost Rectifier driving a small wind turbine. It is used as the input stage of small wind turbines with permanent magnet synchronous generators operating at variable speed. The Boost Rectifier output is connected to an inverter which injects the energy to a distribution power grid. The operation in discontinuous conduction mode allows significantly reducing the Total Harmonic Distortion of the current in the small wind turbine. However, it is necessary to add an input filter so that the switching ripple doesn´t affect the small wind turbine. It is evaluated the convenience of the current sensors placement in the DC side of the rectifier or at the output of the generator. The results demonstrate that it is better to place the sensors at the output of the generator, because it is achieved a smaller THD i and a higher PF.

Analysis and Control of the Inductorless Boost Rectifier for Small-Power Wind-Energy Converters

“…This topology was later applied to a PMSG-based wind energy system also placing a three-phase LC filter and a three-phase boost coil between the generator and the rectifier [18]. A similar configuration, only using the three-phase capacitor bank and three-phase boost inductor was used in [19]. The elimination of the DC capacitor after the rectifier has also been proposed to reduce the generator torque ripple [20].…”

Control of a small wind turbine in the high wind speed region

“…The most widely used converter topology on the generator side for low-power grid-tied systems consists of a diode rectifier and a boost converter [5]- [11], [25]. Alternatively a boost rectifier has also been proposed [26]. An active rectifier with only three active switches was proposed in [19].…”