Fault Tolerant DPFC

This Book presents a new component within the flexible ac-transmission system (FACTS) family called distributed power-flow controller (DPFC). The DPFC is derived from the unified power-flow controller (UPFC). The DPFC can be considered as a UPFC with an eliminated commoThis paper presents a new component within the flexible ac-transmission system (FACTS) family called distributed power-flow controller (DPFC). The DPFC is derived from the unified power-flow controller (UPFC). The DPFC can be considered as a UPFC with an eliminated common dc link. The active power exchange between the shunt and series converters which is through the common dc link in the UPFC is now through the transmission lines at the third-harmonic frequency. The DPFC employs the distributed FACTS (D-FACTS) concept which is to use multiple small-size single-phase converters instead of the one large-size three-phase series converter in the UPFC. The large number of series converters provides redundancy thereby increasing the system reliability. As the D-FACTS converters are single-phase and floating with respect to the ground there is no high-voltage isolation required between the phases.