Design and implementation of IEC 61850 based Multi-type Protection IED

An IEC 61850 based Substation Automation System (SAS) changed existing substation environment to a digital system environment using Ethernet based communication network and microprocessor based IED. Although, system environment has changed to a new environment, but operation and protection schemes have not taken full advantage of the new system environment. In this paper, a Multi-type Protection IED (MPI) is proposed that can be remotely change its protection type without IED reboot or field control. The proposed MPI is designed by using SCL (Substation Configuration Language) engineering based IED and a file transfer service in IEC 61850. The proposed MPI remotely receives a new SCD (Substation Configuration Description) file from station and changes protection type through a parsing of the received SCD file, destruction of existing logical node memories and threads for protection, initialization of new memories for new protection elements, and start of threads for new protection components according to parsing results which are names of logical nodes without recompile or system reboot. Benefits of such MPI are various. For example, a substation operator doesn't need to consider a type of protection IED when substation is designed because the MPI can be set remotely to any type at the station. The number of backup IEDs can be reduced because MPI can be changed to protection IED of any type. A substation operator can reconstruct configuration of protection IEDs suitable for a special or the worst case. The proposed MPI was implemented by SISCO library and Windows programming. For testing the performance of the proposed MPI, two case studies that change the logical nodes of an MPI without reboot and that makes an MPI as a backup IED when primary IED fails are considered. Test results rom these case studies are presented.