Effect of Electrical Trees on the Distribution of Electric Field and Space Charge in Cross-linked Polyethylene Cables

Background: Electrical trees can affect the distribution of electric field and space charge in cross-linked polyethylene (XLPE) cables, and play an important role in insulation aging and breakdown of cables. Therefore, it is important to study the influence of electrical trees in cables. Methods: In this study, the finite element method of second-order tetrahedral element and electromagnetic theory method are used for calculation. A model of XLPE cable with three-dimensional electrical trees is taken as an example for calculation. Results: The results shows that the longer the trunk length is, the greater the electric field intensity at the end of the branch is; the farther the electrical trees are from the insulation side of the high voltage, the more the electric field intensity of each location decreases. Conclusion: With the increase of the resistivity of the trees, the electric field intensity and charge density tend to be stable at the end of the tree.

Numerical approach to high-throughput of nanofibers by a modified bubble-electrospinning

Nanofibers were prepared in large quantities using a modified bubble-electro-spinning, where the distribution of electric field played an important role, and its distribution was studied numerically using 3-D Maxwell equation and verified experimentally. The results showed the increase of electric field strength could decrease the nanofiber diameter and enhance the nanofiber production.