THE EFFECT OF DISTRIBUTED GENERATION ON SHORT CIRCUIT CALCULATIONS OF RADIAL DISTRIBUTION SYSTEMS

The use of distributed generation (DG) within distribution systems has increased in the last two decades, due to institutional requirements and technical advances. The short-circuit capacity of existing distribution networks is often close to their design level, leaving little margin for the interconnection of DG resources. In general all forms of DG contribute to fault levels. The connection of DG can raise the fault level on existing equipment, due to the fault contribution from the DG itself, to values beyond the capacity of existing switchgear. Faults occurring in power networks normally result in a large short-circuit current flow in the system, which may exceed the rating circuit breakers and damage system equipments. The aim of this paper is to use the latest edition of the IEC Standard 60909 for calculating the maximum fault level in the proposed test case, and make a comparison between the IEC60909 and the results obtained from the software in an IEEE 34 node MV test feeder.

Keywords:

Short-Circuit Current , Fault Level , Distributed Generation , IEC60909