Grant: Collaborative Research and Development Grants

Power distribution failure is one of the key factors of electrical power interruption and effective preventive maintenance can significantly increase system reliability. Among the distribution failures, one of the major causes is water treeing in the Cross-Linked Polyethylene (XLPE) insulation of underground power cables. Water trees are regarded as being micro-fisures around water droplets within the XLPE insulation and their chemical composition varies depending on the type of soil the underground cable is buried in. What is important to note is that the composition of the water tree is different from the insulation and as such causes a contrast that can permit the detection and imaging of these faults, especially when ultrasound is used as the non destructive testing technique. Thousands of miles of XLPE underground cable help make up Manitoba's power distribution grid. In order to detect water trees, dissection is currently used to determine the electrical integrity of this insulation. The number and length of trees determine the condition of the insulation and this information help field staff with decisions to prioritize replacement of the cable. This dissection method is quite time consuming and the sample is destroyed and cannot be reused. Therefore, effective non destructive detection and imaging of the insulation part of the underground power cable will translate to faster inspection times and cost reductions. Access to power energy impacts every aspect of modern activities in this country. The reliability of its distribution is paramount and as such there is a cost associated with the system reliability to avoid power interruptions. Thus, minimizing distribution costs directly impacts the maximization of social welfare. The unique configuration of this system will also allow the inspection of other cylindrical objects such as hot sticks that are used to work with hot lines in distribution line repairs.