Abstract
Two topologies are designed by combining a modified-Z-source (MZS) network consisting of three diodes, two inductors and four capacitors to a traditional three-level T-type inverter (3LTI), and embedding either one or two dc sources in the impedance network, which are named as asymmetrical embedded MZS-3LTI (AEMZS-3LTI) and symmetrical embedded MZS-3LTI (SEMZS-3LTI). The proposed topologies provide a highly boosted ac output voltage with five voltage levels and ensure a continuous dc source current by adopting the embedded concept. Operating analysis is performed and a comparison of the two proposed topologies with five different topologies combining the impedance network and 3LTI or neutral-point-clamped (NPC) inverter is provided. A novel modulation technique is proposed for effectively controlling the upper and lower shoot-through states with a simple logic circuit and balancing a neutral-point voltage. The validity of the proposed topologies and the modulation technique is demonstrated through simulation and experimental results.
Highlights
Nowadays, multilevel inverters have been widely employed in various industrial applications such as medium-voltage ac motor drives [1] and wind turbine or photovoltaic (PV) generation systems [2], [3]
The 3LTI can be applied in various industrial applications such as photovoltaic (PV) generation [12], permanent-magnet synchronous motor (PMSM) drives [13], [14], and energy storage systems [15]
This paper proposed two types of topologies, AEMZS-3LTI and SEMZS-3LTI, designed by integrating a modifiedZ-source impedance network to the traditional 3LTI, and embedding either one or two dc sources in the impedance network
Summary
Multilevel inverters have been widely employed in various industrial applications such as medium-voltage ac motor drives [1] and wind turbine or photovoltaic (PV) generation systems [2], [3]. The space vector modulation scheme and carrier level shifted modulation method of the quasi-Z-source 3LTI (qZS-3LT2I) topology realized by combining two symmetrical quasi-Z-source networks and three-phase 3LTI are proposed to reduce the common-mode voltage by balancing the neutral-point voltage [21]–[23]. The qZS-3LT2I has a continuous source current It requires a large number of passive components that results in increased weight, volume, and cost of the power converter. The proposed topologies are designed by attaching the single modified-Z-source (MZS) impedance network proposed in [32], [33] to 3LTI, and embedding either one or two dc sources at the MZS network, which are named asymmetrical embedded MZS-3LTI (AEMZS-3LTI) and symmetrical embedded MZS-3LTI (SEMZS-3LTI), respectively They can improve the boost ability and ensure a continuous dc source current without an extra capacitor or filter by employing the embedded concept. The steady-state operations of the two proposed topologies are analyzed through their equivalents circuits
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
