Carrier-Based Discontinuous PWM Method for Vienna Rectifiers

Vienna rectifiers, which are nongenerative-boost types of rectifiers, are used in grid-connected applications with a unity power factor such as telecommunication systems and wind turbine systems. These rectifiers are advantageous in that they have low total harmonic distortion and efficiency. There are many switching methods, which are different from those of threelevel topologies, for Vienna rectifiers. In this paper, we propose a carrier-based discontinuous pulse width modulation (CB-DPWM) method. This method is simple compared to the discontinuous PWM (DPWM) method for Vienna rectifiers based on space vectors and guarantees normal rectifier operation for all modulation index (M_a) values. We perform experiments to verify the suitability and performance of the proposed CB-DPWM method.

I. Introduction

Grid-connected voltage-source pulse width modulation (PWM) rectifiers at unity power factor, which are nongenerative-boost types of rectifiers called Vienna rectifiers [1] –[3], have the advantage of having a low total harmonic distortion (THD) of input currents and high efficiency [4]– [6]. There are many topologies that represent Vienna rectifiers, and these topologies are used in various applications, such as telecommunication power systems and wind turbine systems [2]–[5], [7], [8], [12].