Single Ended Fault Locator for Power Transmission Lines Connected with Inverter Based Resources: Problems and Mitigation Approach

Single-ended fault location accuracy is adversely influenced by integration of the inverter based renewable resources (IBRs). In this paper, we cover a more generic examination of performance of single-ended fault locator for lines connected with IBRs. This analysis is used for understanding the causes of high fault location error for lines with IBRs. This information can be used for designing accurate single-ended fault locator for IBR connected networks. The paper also presents a mitigation approach which has potential improvement in fault location accuracy by using remote terminal current. The remote current is readily available, as most of the IBR connected lines are employed by differential relays as main protection. The proposed mitigation approach can be implemented in the existing line differential protection IEDs (Intelligent Electronic Devices). The approach is demonstrated using EMTDC simulation of a 220-kV, 200km transmission line connected with IBRs. Validation with field data confirms the accuarcy of proposed mitigation approach.