Improved Mayr-Cassie Combinatorial Arc Model of Tree Contact Incipient Fault Simplified by MHD

Overhead lines are susceptible to climate and environment, short-term contact with the branches around the distribution lines will cause the grounding fault arc, describe as the tree-contact incipient fault., its intermittent and frequent occurrence can cause serious accidents such as disconnection of lines and fire. By studying its generation mechanism and development process, and extracting fault signal characteristics, the detection and identification of tree-contact incipient fault can be realized, thus the operation and maintenance level of distribution lines can be improved. In order to realize the early detection of the tree-contact incipient fault, the simulation of distribution line with arc black box model is used to guide the detection and identification of grounding fault arc. However, the traditional arc black box model is difficult to accurately reflect the evolution mechanism of tree-contact fault arc. Therefore, in this paper, the physical model in the process of tree-line separation is established by magnetic fluid simulation. By equating the physical model into a mathematical model, the black box model of tree-line grounding fault arc of distribution line is constructed. Finally, the reliability of the model is verified by comparing the simulation results with the experimental results.