Today worldwide distributed generation (DG) takes a very important role in the operation of
distributed electric power systems. However, the existence of distributed generation may have
impacts on different topics, such as fault currents, fault pro
tection, coordination schemes or
fault location. If there is short-circuit in the system, the presence of one or more distributed
generators can affect the fault current levels, the monitoring of voltages and currents at the
substation. The main supply generation will not have to inject as much power to the line because
of the DG and, therefore, voltages and currents at the substation will be different from the ones
that would be measured without DG .
