Insulated Cooperation of DC 3kV Feeding Circuit


Kohji AJIKI, Toshikatsu ITO, Jiro ITO
Now 1.5kV is the standard feeding voltage of DC electric railway now mainly used in Japan, but in future it is expected to be increased to 3kV. Therefore we tested and studied on the insulated cooperation and insulated spacing of DC 3kV feeding circuit as part of the research. The maximum surge voltage at the 1.5kV circuit is about 2.2 times as large as the standard voltage of 1.5kV at the start of the feeding. Also we have grasped the DC dirty insulation characteristic of the disc type suspension insulator and the long rod insulator and the spacing distance capable of breaking the arc from the test. We can recommend a lightning impulse withstand voltage of 180kV and use of 2 series insulator of 250mm type. The spacing of the arresters, insulated spacing, etc are almost the same as in the DC 1.5kV feeding circuit.