Farshid Najaty Mazgar - Department of Electrical Engineering, Islamic Azad University Ahar branch
Mehrdad Tarafdar Hagh - Faculty of Electrical and Computer Eng, University of Tabriz
Seiede Elahe Baghbani

Nowadays the need for the prevision of three-phase loads with different amplitudes and frequencies is felt in variety of industries. Different transformers and power electronicconverters are required to feed these loads. On the other hand as a result of their massive iron core and the heavy windings thepower transformers have come to be considered among the huge and expensive equipments of power system. Since the size of the transformers and the maximum power transition arereversely related, a new family of electronic power transformer has come into existence which increases the transformerfrequency, using power electronic converters. In addition to voltage transformation and good isolation which they bringabout, these transformers are also associated with significant advantages, including considerable reduction in the size, power quality improvement, voltage profile improvement, etc. Thepresent paper introduces a new structure for the power electronic transformers which keeping the capabilities ofprevious power electronic transformers is capable of feeding two three-phase loads simultaneously with different amplitudes and frequencies in the output, while using the minimum number of power switches. The performance and capability of the recommended structure has been put to a test in MATLAB/SIMULINK software.

Power Electronic Transformer, high frequency, voltage sags and swells, 9 switch inverters