AC-DC Power Conversion Systems for Open-End Winding PMSM Based on Vienna Rectifiers

This paper proposes three unidirectional ac-dc conversion power systems for wind energy conversion system (WECS) applications. These topologies are based on Vienna rectifiers and have reduced number of controlled switches, which allows reduce size, costs and is still possible to obtain low current harmonic distortion. They are composed of a series connection of two three-phase converters associated to a permanent magnet synchronous machine (PMSM) by an open-end winding (OEW) configuration. Compared with the three-phase rectifier with reduced number of controlled switches, proposed topologies offer a higher levels-per-switch ratio, allowing to achieve a sinusoidal converter current with same or lower harmonic content. Besides this, they can offer lower switch blocking voltage. These characteristics make them very interesting options to the manufacturers due to reduced costs and better power quality offered. The system model, PWM technique and control strategy are discussed. Simulation and experimental results are provided in order to validate their performance and feasibility.