Measured impedance at source node of a distribution feeder with loads having emf

Distance protection is not utilized in distribution networks, unlike the transmission systems, due to the inherent characteristic of the distribution networks and the additional required facilities of the distance protection, compared with overcurrent protection, which is in use in the distribution systems. This paper studies the measured impedance at the source node of a distribution feeder with the loads with the internal emf. The ideal tripping characteristic is presented for the distribution feeder. The variation of this tripping characteristic is studied as a function of the fault location. The especial case of the absence of the fault resistance is highlighted.