Series Z‐source and nine‐switch dual‐output inverter stage two‐stage matrix converter

Abstract

Nine-switch dual-output inverter stage two-stage matrix converter (NS-TSMC) has been widely applied in dual AC motors drive system, while it has the shortcoming of low voltage transfer ratio. Based on the NS-TSMC, a modified topology, named as series Z-source and nine-switch dual-output inverter stage two-stage matrix converter (ZS-NS-TSMC), is proposed, in which the series Z-source network is connected between the rectifier stage and nine-switch dual-output inverter stage (NS-DOI). In the presented topology, a brief shoot-through vector is employed, which can improve the voltage transfer ratio. Other advantages of the series Z-source network, such as low voltage stress of Z-source capacitor, zero dead-time of NS-DOI and limiting inrush current at startup, are discussed in the study. Furthermore, the dual space vector modulation is presented, which can achieve the merits of unity input power factor, sinusoidal input and outputs. Besides, the sinusoidal outputs, the capability of boosting voltage and adjustable output voltage amplitude are also discussed by the mathematical proof. Finally, an experimental prototype is set up based on the controllers of TMS320F28069 (DSP) and EPM570 (CPLD), the results of which verify the feasibility and desired advantages of the proposed topology and modulation strategy.