Multilevel Diode-clamped Converter for Photovoltaic Generators with Independent Voltage Control of each Solar Array
Location: USA
Publication date: 2008-06-01
Published in: IEEE Transactions on Industrial Electronics, July 2008
ref. DOI: 10.1109/TIE.2008.924011

Local members

Joan Rocabert

PhD. Senior Researcher

External members

Busquets-Monge, S. , Alepuz, S. , Bordonau, J.



In photovoltaic (PV) power systems where a set of series-connected PV arrays (PVAs) is connected to a conventional two-level inverter, the occurrence of partial shades and/or the mismatching of PVAs leads to a reduction of the power generated from its potential maximum. To overcome these problems, the connection of the PVAs to a multilevel diode-clamped converter is considered in this paper. A control and pulsewidth-modulation scheme is proposed, capable of independently controlling the operating voltage of each PVA. Compared to a conventional two-level inverter system, the proposed system configuration allows one to extract maximum power, to reduce the devices voltage rating (with the subsequent benefits in device-performance characteristics), to reduce the output-voltage distortion, and to increase the system efficiency. Simulation and experimental tests have been conducted with three PVAs connected to a four-level three-phase diode-clamped converter to verify the good performance of the proposed system configuration and control strategy.