Shielding Properties of Isolated-Phase Bussystems

The shielding effectiveness of an isolated-phase bus with continuous enclosures depends on a number of parameters. To study this problem we developed a system to measure amplitudes and phase angles of the currents in an isolated-phase bus during regular operation in a power plant. In our theoretical description we give new inductance values for three cylinders in situations with strong proximity effects. The flux near the short-circuiting ircuiting end connection is strongly influenced by the currents and fields outside the bussystem. Good agreement ent between calculated and measured sheath currents is reported for three bussystems. The asymmetry between the currents in the two outer sheaths is explained.