The modeling of over-current reclosing relay using dynamic link library

This paper presents a new method of modeling using a dynamic link library (DLL) function in the electro-magnetic transients program - restructured version (EMTP-RV), in which we have simplified the procedures of over-current reclosing relay modeling. The EMTP-RV is the enhanced computational engine. and EMTPWorks is a new graphical user interface (GUI) of EMTP. The major improvements to EMTP-RV are a new approach with built-in models and encapsulation, user-defined modeling, and a code structure designed to be expandable to specialized toolboxes using the DLL function. The DLL function is designed to allow EMTP-RV users to develop advanced program modules and interface them directly and intimately with the EMTP-RV engine. The modeled over current reclosing relay is verified by simulating the various types of faults in the distribution system. The results show the validity of the over current reclosing relay model.