Modulation Techniques for Three-Phase Four-Leg Inverters

Three-phase four-leg inverters are typically employed to supply unbalanced loads avoiding the use of a transformer. Usually, the inverter control is performed by modulation techniques, such as the threedimensional one, requiring complex mathematical algorithms. The paper suggests a different approach, based on the separation of the control of the fourth leg from that of the other phases, allowing the application to the three inverter phases of traditional SVM techniques and avoiding the employment of complex procedures. Key-Words: Converters, Modulation, Power Generation, Uninterruptible Power Supplies.