Space vector modulation based switching schemes for high frequency link matrix rectifier in discontinuous conduction mode

Abstract

A high-frequency link matrix rectifier with a pure capacitive output filter has the advantages of reduced converter size and clamped voltage over the rectifier diode. However, when the converter operates in discontinuous conduction mode (DCM), there is high input current distortion. The distortion has to be compensated such that the total harmonic distortion (THD) does not exceed 5%. The straightforward way of reducing distortion is by designing the switching scheme. In this study, switching schemes based on space vector modulation have been studied to improve the input current quality in DCM. Several existing switching schemes and newly proposed switching schemes have been analysed and compared. A 600 W laboratory prototype has been built to verify the effect of switching schemes over input current quality. The experimental results show that the input current THD can be greatly reduced by applying proper switching scheme.