In this paper a new inverter unit is proposed. It is a compact switched-capacitor-based inverter, which is combined of four switches, two diodes and four capacitors. Since this inverter unit is a mid-point-clamped inverter, it can mitigate the capacitive leakage current in many applications. One of the main applications of the proposed inverter is in grid-tied photovoltaic (PV) systems, where the commonmode current brings many challenges. Other than the mentioned feature, the proposed inverter includes the following advantages: i) spontaneous balancing of the voltage across the capacitors without needing any control system or auxiliary circuits, ii) capability of full reactive power transfer, iii) low voltage stress on the capacitors compared to common three-level inverter topologies (NPC, T-type-NPC, FC and etc.), and iv) symmetric switching sequence, which causes a continuous input current. The feasibility and versatility of the proposed inverter unit is validated by experimental tests, which are conducted by using a lab-scale prototype.
In this paper, a new structure for multilevel converter based on improved H-bridge converter is presented. The proposed topology is a symmetric topology since the values of all voltage sources are equal. The proposed symmetric structure is a general topology which can be extended for any number of voltage levels at output voltage waveform to obtain the least value of total harmonic distortion (THD). Reduction of switching losses, conduction losses, the number of on-state switches in the current path, utilized DC voltage sources, and gate driver circuits are the main advantages of proposed symmetric structures in comparison with other symmetric topologies. All mathematical analysis on the proposed structure is presented in terms of power losses and maximum blocked voltage by switches. The comparison results with other recently presented symmetric topologies and traditional multilevel converter structures are provided. Experimental results for a thirteen-level converter based on presented structure are provided to validate the practicality of the suggested multilevel structure.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.