FEM calculation of the sheath currents in 110Kv cables

Abstract

Cross-bounding system is the most commonly used method to reduce sheath current. The sheath currents of cables are induced by currents in the cable cores, and sheath currents also increase when the loads increase gradually. The current carrying capacity of the cable is limited by sheath currents further, owing to their thermal effect, which is not favourable to the heat dissipation and operation of the cable. The sheath currents of single cable and the sheath currents of single loop cables in the case of cross-bounding interconnection are calculate by FEM including configurations of three phase cables in square triangle, horizontal and right angled triangle with the same distance between the cable cores. The results show that the right triangle arrangement should be preferred in order to minimize the sheath circulation.