Experimental Comparison of Two-Level Full-SiC and Three-Level Si–SiC Quasi-Z-Source Inverters for PV Applications

• Main Authors: Serhii Stepenko, Oleksandr Husev, Dmitri Vinnikov, Carlos Roncero-Clemente, Sergio Pires Pimentel, Elena Santasheva
• Format: Article
• Language: English
• Published: MDPI AG 2019-06-01
• Series: Energies
• Subjects: DC–AC converters; efficiency; neutral-point-clamped inverter; PV applications; PV inverters; PV systems; quasi-z-source; two-level inverter; three-level inverter; converter topologies
• Online Access: https://www.mdpi.com/1996-1073/12/13/2509
• ISSN: 1996-1073

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.