Understanding Electrical Treeing Phenomena In Xlpe Cables Used By Indian Industries

The electrical trees formation in the cable insulation is a major cause behind the failure of underground XLPE cables. India has few wire and cable manufacturing companies who are leading the industry and making people aware of electrical treeing phenomena in detail.

A defect site in cable insulation can form sorts of tree structure- tree-like trees, bush-type trees, intrinsic type, and fibrillar type trees as per the voltage. When XLPE cables manufacturers in India conducted a test, they discover that a higher rate of voltage influences the rate of tree propagation that results in reduction of cable insulation life. They also tried to identify the partial discharges, caused by the propagation and inception of electrical trees, via UHF technique.

What Is The Result Of The Test?

In the study, they discover that the major cause behind the cable insulation failure is -the formation of electrical trees in the presence of defect site. The insulation structure defect can be of two kinds- conducting or non-conducting. The shape and size of the defect depends on the local electric field that is responsible for altering the shape and mode of propagation of tree.

 Identifying and classifying the sorts of discharge using Ternary Diagram

The job of classifying the sorts of tree patterns that develops via generated UHF signal is really tough. At present operation, the partial power analysis to the UHF signal created due to discharges. Partial power is measured by summing the power spectrum in a certain range of frequencies set by user, dividing it by the gross or total power. This technique is similar to the process that is used to create gas in oil ratio.

This identical process is accepted to visualize and categorize the tree pattern types in XLPE cables. India holds many top leading wire and cables exporters who aim for delivering defect-free XLPE cables to the rest of the world. It is because only a defect site is responsible for generating electrical trees, which later become a cause of failure of cable insulation.