Design of CORDIC-based Digital Protective Relay

Abstract

Protective relays are used to show the current status of a given power system. It is used to determine whether parameters like voltage or current violate any trip or reset specification or condition. In this project, overcurrent time invariant model of protective relay is implemented using CORDIC algorithm. Here we use CORDIC algorithm to implement the relay flowchart. All of the arithmetic calculations and relaying algorithms can be managed by a CORDIC processor. As CORDIC algorithm is simple to implement, it has a very low FPGA footprint and it negates any need of multipliers as well. In this project: 1) A basic implementation of sine/cosine calculation of CORDIC using VHDL in Xilinx ISE 10.1 is implemented to check the accuracy 2) Various modules needed to calculate the protective relay status of trip or reset condition were developed 3) A final implementation of overcurrent relay was done and accuracy checked