Pulsewidth Modulations for the Comprehensive Capacitor Voltage Balance of n-Level Three-Leg Diode-Clamped Converters

• Published in: IEEE transactions on power electronics Vol. 24; no. 5; pp. 1364 - 1375
• Main Authors: Busquets-Monge, S., Alepuz, S., Rocabert, J., Bordonau, J.
• Format: Journal Article Publication
• Language: English
• Published: New York, NY IEEE 01-05-2009; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Applied sciences; Capacitor voltage balance; Capacitors; Capacitors. Resistors. Filters; Circuits; Converters; Convertidors; Convertors; Dielectric, amorphous and glass solid devices; diode-clamped; Diodes; Electric current converters; Electric currents; Electric potential; Electric power; Electrical engineering. Electrical power engineering; Electrical equipment; Electrical machines; Electronics; Electrònica de potència; Enginyeria electrònica; Exact sciences and technology; Guidelines; Leg; Modulation; multilevel; Optoelectronic devices; Phase modulation; Power electronics; Pulse duration modulation; Pulse modulation; Pulse width modulation; Pulse width modulation converters; pulsewidth modulation (PWM); Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Space vector pulse width modulation; Strategy; Switching converters; Various equipment and components; virtual vector; Voltage; Zero voltage switching; Àrees temàtiques de la UPC; Performance evaluation; diode-clamped; pulsewidth modulation (PWM); Electric energy transportation; Direct current line; multilevel; Power capacitor; Experimental study; virtual vector; Switching; Three phase current; Implementation; Light emitting diode; Capacitor voltage balance; Switching conditions; Neutral point connection; Optoelectronic device; Converter; System simulation; Pulse duration modulation; Multilevel system; Comparative study; Power transmission line
• ISSN: 0885-8993; 1941-0107
• DOI: 10.1109/TPEL.2009.2016661

In the previous literature, the introduction of the virtual-space-vector (VV) concept for the three-level, three-leg neutral-point-clamped converter has led to the definition of pulsewidth modulation (PWM) strategies, guaranteeing a dc-link capacitor voltage balance in every switching cycle under any type of load, with the only requirement being that the addition of the three phase currents equals zero. This paper presents the definition of the VVs for the general case of an n -level converter, suggests guidelines for designing VV PWM strategies, and provides the expressions of the leg duty-ratio waveforms corresponding to this family of PWMs for an easy implementation. Modulations defined upon these vectors enable the use of diode-clamped topologies with passive front-ends. The performance of these converters operated with the proposed PWMs is compared to the performance of alternative designs through analysis, simulation, and experiments.