Incorporating distributed generation (DG) into distribution networks could lead to nuisance fuse blowing because of miscoordination between recloser and fuse. This paper presents a new non-standard characteristic for microprocessor-based recloser to improve fuse saving strategy in distribution networks with/without DG. The proposed scheme uses only local measurements of the three phase voltage and current magnitudes, thereby obviating the need for communication links between the recloser and DG units. The new characteristic is self-adaptive, i.e. it changes the operating time of the recloser in response to fault conditions to maintain adequate grading margin with downstream fuses. The new recloser characteristic is tested by simulation study for an Iranian practical distribution network. In addition to the test cases with high penetration levels of DG, the absence of DG in the distribution network is also analysed on the recloser-fuse grading time margin. The test results validate the performance of the new recloser characteristic under different fault conditions. The comparative results show considerable improvement over the previously proposed methods in the literature.

Keywords: Distribution network, Distributed generation, Fuse saving, Microprocessor-based recloser