Simple Unified Approach to Develop a Time-Domain Modulation Strategy for Single-Phase Multilevel Converters

• Published in: IEEE transactions on industrial electronics (1982) Vol. 55; no. 9; pp. 3239 - 3248
• Main Authors: Leon, J.I., Portillo, R., Vazquez, S., Padilla, J.J., Franquelo, L.G., Carrasco, J.M.
• Format: Journal Article
• Language: English
• Published: New York IEEE 01-09-2008; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Modulation; multilevel systems; Optimization methods; Photovoltaic cells; Photovoltaic systems; power conversion; Power generation; Space vector pulse width modulation; Support vector machines; Switching converters; Time domain analysis; Topology; Voltage control; Power conversion; Modulation; Multilevel systems
• ISSN: 0278-0046; 1557-9948
• DOI: 10.1109/TIE.2008.928141

Single-phase power converters are widely used in power applications as photovoltaics and fuel-cell power conditioners. In addition, multilevel converters are a well-known solution in order to achieve high-quality output waveforms in power systems. In this paper, a time-domain duty-cycle computation technique for single-phase multilevel converters named 1DM is presented. The proposed technique is based on geometrical calculations with outstanding simplicity and generality. The proposed modulation technique can be easily applied to any multilevel converter topology carrying out the necessary calculations. The most common multilevel converter topologies have been studied in this paper as examples to introduce the proposed modulation strategy. Any other multilevel converter topology could be studied, and the corresponding 1DM could be easily developed. In addition, the well-known optimized voltage balance strategy for voltage capacitor control using the redundant switching states of the system is applied working with the proposed 1DM method, showing that both techniques are compatible. Experimental and simulation results for several single-phase multilevel converters are shown to validate the proposed modulation technique.