Adaptive overcurrent relays coordination based on multiple sequence alignment algorithm (MSA)

The overcurrent relays (OCRs) as main protective devices have been most commonly used to protect radial distribution system and must set correctly when load, generation-level or system-topology changes. For digital OCRs based on microprocessor, adaptive setting coordination stored at the memory. This paper demonstrates the technique of bioinformatics to determine the correct setting of available OCRs by comparing data input sequence from all of the OCRs currents and connected generation with database sequences at the memory to find similarity when fault occurs at any bus. The result shows the accuracy of similarity scoring even though there is junk of data input when one or some OCRs' not send a fault current data information passing.