Sheath voltage calculations in long medium voltage power cables

This paper investigates the operation of single core underground medium voltage cables connected in parallel. The examination is based on an existing power cable arrangement connecting a 38 MW wind farm with the transmission grid. The cable arrangement consists of nine single core cables connected in parallel to form a triple 3-phase system. Several connection scenarios such as the earthing of the cable sheaths at one or both ends and the application of sheath cross-bondings are examined. Various simulation parameters are also investigated such as the grounding resistance of the cable sheaths and the number of the cable sheath transpositions. The respective voltages and currents induced on the cable sheaths are calculated under steady-state and short circuit conditions.