Three-dimensional dynamic simulation of motion characteristics of metal particle in DC GIL.

Dynamic behavior simulation of metal particles in gas-insulated metal-enclosed transmission lines (GIL) is crucial for predicting their migration process and distribution pattern. However, existing two-dimensional (2D) simulations of particle motion characteristics fail to accurately reflect real-world particle behavior due to the limit of spatial dimensionality. To address these issues, this study develops a three-dimensional (3D) simulation model comprising an electrostatic field analysis module and a particle tracking module, grounded in dynamic contact theory and utilizing random reflection angle. Our simulation systematically investigates the motion characteristics of spherical metal particles between electrodes and around basin-type insulators, as well as the influence of key parameters. The simulation results demonstrate that an increase in reflection angle, which determines the coupling effect of radial and axial components of particle velocity, leads to the significant expansion of radial distribution range and maximum axial displacement. Besides, particles, whether far from or near the concave surface of basin-type insulator, repeatedly collide between the high-voltage (HV) conductor and the shell upon being lifted, followed by migration toward the convex side of insulator; particles near the convex surface exhibit surface-climbing behavior along the profile of insulator. Furthermore, particle vitality has a positive correlation with applied voltage but an inverse relationship with particle size; collision frequency is predominantly influenced by applied voltage and material properties, along with little dependence on particle size. These findings can provide a robust theoretical foundation for predicting metal particle behavior in GIL systems.