Cable Rejuvenation: Improving Grid Resilience for Over 3 Decades

Injecting medium-voltage underground electrical cables with dielectric silicone fluid to chemically “dry” the cable and react out the water trees, was first accomplished in 1987. In the years since that time there have been many advances in this technology. The rejuvenation fluids have gone through many chemical changes. There have been advancements in the terminations and connections for underground cable. Strand-filled cables can now be injected with a newly patented process. This has led to over 150 million feet (>45,000 km) of cable having been treated with silicone injection through the interstitial region of the conductor. Less than 1% of cables rejuvenated have experienced dielectric failure. The injection of silicone fluid extends the life of these cables by many years. Highlights of the history, process and scientific advances made will be discussed.