This study presents a novel three‐level neutral‐point‐clamped quasi‐Z‐source inverter in the single‐stage buck‐boost multilevel inverter family. The topology was derived by combining the properties of the quasi‐Z‐source network with those of a three‐level neutral point clamped inverter. It features such advantages as low voltage stress of the switches, single‐stage buck‐boost power conversion, continuous input current, short‐circuit withstandability and low total harmonic distortion of the output voltage and current. The authors present a steady state analysis of the topology along with a special modulation technique to distribute shoot‐through states during the whole fundamental period. Component design guidelines for a single‐phase case study system are described. All the findings have been confirmed by simulations and experiments. The topology could be recommended for applications requiring continuous input current, high input voltage gain and enhanced quality of the output voltage.

This paper describes a new modulation technique for a single phase three-level neutral-point-clamped qZS inverter. The proposed converter is intended for applications that require input voltage gain and high quality of the output voltage. The simulation and experimental results are presented and discussed.

This paper presents a CCM analysis of a new modification of a three-level single phase neutral-point-clamped inverter. The proposed topology combines advantages of the three-level neutral-point-clamped full-bridge inverter with those of the quasi-Z-source inverter. The three-level neutral-point-clamped quasi-Z-source inverter is especially suitable for renewable energy sources. The steady-state analysis of a three-level neutral-point-clamped quasi-Z-source inverter in the case of the continuous conduction mode is presented. The conditions of the continuous conduction mode are obtained and analyzed.

The paper presents a comparative study of two solar string inverters based on the Quasi-Z-Source (QZS) network. The first solution comprises a full-SiC two-level QZS inverter, while the second design was built based on a three-level neutral-point-clamped QZS inverter with Silicon based Metal–Oxide–Semiconductor Field-Effect Transistors (Si MOSFETs). Several criteria were taken into consideration: the size of passive elements, thermal design and size of heatsinks, voltage stress across semiconductors, and efficiency investigation. The Photovoltaic (PV)-string rated at 1.8 kW power was selected as a case study system. The advantages and drawbacks of both solutions are presented along with conclusions.

This paper presents a comprehensive review based on the features and drawbacks of the quasi-switched boost inverter (qSBI) topologies. The qSBI derived configurations are well suitable for low power applications due to their reduced number of components. This work focuses on the topological review of qSBI derived topologies and serves as a reference for further derivation and research on the selection of suitable topology for the specific renewable energy applications, particularly based on the photovoltaic (PV) converters.

This article presents a comparative analysis of the input current parameters for active power factor corrector (PFC) based on conventional boost converter (BC) and zero-current-switching quasi-resonant boost converter (ZCS-QRBC). The comparison was performed taking into account the spectral composition of the input current (individual harmonic levels, total harmonic distortion) and power factor. It has been shown that both converters rated for 1 kW output power are compliant with the requirements of international standard IEC61000-3-2.