Research on Modulation Technique of Novel AC/DC/AC Voltage Source Converter

This paper proposes a novel AC/DC/AC voltage source converter without or with a quite small dc-link capacitor. Because an advanced modulation wave reconstruction-SPWM (AMWR-SPWM) technique is adopted which can greatly eliminate the harmonics of output voltage, the DC filter capacitor is greatly decreased or even removed. In addition, the size of the input ac filter and the output ac filter is reduced. The principle of operation and harmonics elimination of the novel converter topology are elaborated. A through analysis on its performance is presented. This converter has many advantages such as simpler structure, higher reliability, more effective harmonics elimination. The performance of this converter using AMWR-SPWM technique is compared with traditional inverter by simulation, and the results show that the theoretical analysis is correct.