Non-Homogeneous Sampling Rate Wide Area Backup Protection using Synchrophasors and IED Data

Fault currents may result in cascading failures and even system collapse if not detected and cleared on time. To account for the possibility of failure of primary protection under stressed system conditions, an extra layer of protection is commonly employed, referred to as backup protection. This paper introduces an effective formulation for realizing remote backup protection using available data from PMUs and Intelligent Electronic Devices (IEDs). The proposed method is split into three main stages. The first stage deals with the zoning detection of the fault. The second stage is aimed at faulted line detection, and finally, the third stage determines the fault distance on the faulted line. The method is designed to take full advantage of measurements provided by PMUs and IEDs. The challenges associated with different reporting rates are resolved thanks to the dynamic decimator employed to this end. The proposed method has been implemented in real-time by applying co-simulation with MATLAB and validated using the New England IEEE 39 bus system with several fault events.