Multifrequency electrical systems: From power transmission to power electronic converters

This paper presents an overview of previous and current research, as well as, the utilization of technologies that implement multiple superposed frequencies in electrical energy systems of various levels. Unlike communication systems, the field of electrical energy engineering, across all scales, seeks to be devoid of any additional frequencies, as they are conventionally regarded as undesired harmonics. By examining the various applications that do employ two or more frequencies ( including dc), this paper sheds light on the motivation, challenges and benefits of these systems, in their respective fields. These include a multitude of power levels, that cover the transmission range, micro-grid level and finally, specific, individual applications.