Underground High-Power Transmission: First Results of Testing A 110 KV Low-Pressure Oil-Filled Cable with a Water-Cooled Conductor in Berlin (West), Germany

The Berliner Kraft-u. Licht (BEWAG)- AG have been conducting investigations during the last several years On a 110 kV low-pressure oil-filled high-power cable with a water cooled conductor and a load capacity of 950 MVA at 110 kV. After sucessful transport of the cable drums (weight: 16 metric tons; diameter: 4.9 m) from the manufacturing in Cologne, West Germany, to Berlin (West), and after laying of the cable over a 300 m stretch, the commissioning tests in accordance with IEC and VDE* standards have been concluded, and several loadings with a current of 5000 A have been performed. Now, after completion of various improvements in the test system, preparations are underway for initiation of long-term testing over a period of approx. 18 months.