Towards active distribution networks fault location: Contributions considering DER analytical models and local measurements

This paper presents an analytical methodology to estimate the fault location in active distribution networks. State-of-the-art solutions for active distribution networks fault location consider wide-area measurements, which include synchronized measurements obtained by Phasor Measurement Units (PMU). For distribution networks though, the capital cost of such solutions is prohibitive. Most recently, solutions have been proposed without considering synchronized measurements. However, they have some limitations, such as not considering multiple inverter-interfaced Distributed Energy Resources (DER). The solution presented is composed of a load flow based approach, which uses only locally available measurements. A ladder iterative technique is proposed to estimate the system state variables during the fault period. DERs models, which consider various modes of operation and fault conditions are used. An impedance formulation which considers distribution networks inherent characteristics is presented. The proposed methodology is validated on the IEEE 34-nodes test feeder. The ease of implementation of design, formulation of parameters and encouraging test results indicate potential for real-life applications.