This paper presents a Multi-Fed Power Electronic Transformer (MF-PET) for use in power distribution electrical systems. The MF-PET is a power electronic transformer with two or more AC/DC rectifiers at its input port, which may be connected to different feeders. Thus, it is possible to share the demand among feeders. Through a proper control, the AC/DC rectifiers may handle active power from the feeders (independently of the load type), may protect the load from sag/swell events, and may transfer power among feeders. This paper presents a three-phase MF-PET model. A small-scale laboratory prototype is shown and its application to distribution electrical system is discussed, exhibiting the MF-PET as a power electronic building block (PEBB) for its integration into electrical grids, enhancing the distribution system flexibility and contributing to the smart grid concept.