Fuse-Saving Strategy Using Back-to-Back Converter for Microgrid

The fuse is commonly coordinated with other protective devices to prevent a long interruption caused by blown fuse during temporary faults. This paper proposes the fuse-saving strategy using back-to-back (BTB) converter for microgrid. The BTB converter, which is an interface between microgrid and main grid, has the recloser capability coordinating with the fuse. This fuse-saving strategy does not require the recloser installation. The investment and maintenance costs of recloser can be removed. Moreover, the time-current characteristic (TCC) of recloser capability is properly varied to avoid the miscoordination caused by distributed generator (DG) fault current contributions. According to the simulation results, the proposed fuse-saving strategy can prevent the damage of fuse during temporary fault. The voltage level and frequency of microgrid are also restored to the nominal values after the fault is extinct.