Computer Model of "Smart Grid" for Power Transmission Lines with Tree-Like Topology

The paper is devoted to the development of the reflectometry method of detection of line fault position (DLFP) for power transmission lines (PTL) with tree-like topology, which include 6-10 kV power lines, poorly studied but it is in important national economic interest. The main problems of using reflectometry-based DLFP are associated with the uncertainty of determining the fault location and a significant increase in noise levels due to re-reflections from side lines of topology. To solve these tasks, an original idea of a two-stage PTL diagnostic system with a tree-like structure is proposed. The paper presents the developed computer model of smart grid, which implements a two-stage diagnostic system. The results of modeling for PTL with different numbers of side lines are presented when simulating such damages as line breakage, interfacial short circuits and short circuit to the ground. The sensitivity of a two-stage method for detection of line fault position is shown. The results of computer modeling show that the reflectometry method in the case of using a two-stage DLFP system is applicable on branched power lines. It is shown that most of the damages associated with line breakage and short circuits of various types are confidently diagnosed. At the same time, approximately 20% of the damages cannot be localized by the proposed system. With an increase in the number of side lines, the accuracy of the DLFP drops sharply and the diagnosis of PTL with a number of side lines of more than three will require the use of more sensitive receiving and transmitting equipment.