Medium voltage XLPE cable condition assessment using frequency domain spectroscopy

Cables are valuable assets, critical for ensuring the continued reliability of electric power delivery. XLPE cable systems have become increasingly ubiquitous, since their introduction in the 1960s. Improvements in the XLPE manufacturing technology resulted in the advent of tree-retardant XLPE (TRXLPE) type cables in the 1980s. Most of the distribution utilities have already either initiated or completed the process of replacing their old PILC cable infrastructure with polymeric type cables. However, the XLPE cable systems are still prone to accelerated aging due to water treeing and thermal aging effects. Water trees are bush-like structures that develop under service, specifically due to the presence of moisture [1]. Figure 1 shows the different densities of water tree formation in XLPE cables, from light to extremely large.