Insulation coordination for HVAC cable sheath bonding systems in mixed OHL-UGC connections using the lightning statistics: A case study for the Dutch 110 kV transmission grid.

• In this paper, a methodology is presented that facilitates the calculation of the failure rate performance of a cable's sheath bonding system due to lightning strikes on the connected overhead line(s). • The methodology consists of two steps: 1) detailed ATP simulations for the calculation of the minimum critical lightning current that results in the exceedance of the defined insulation withstand levels of the sheath bonding system and 2) the calculation of the failure rate performance based on the (national) lightning statistics. • The findings and conclusions of a practical study case in the Dutch 110 kV transmission grid are presented. This case refers to a double-circuit syphon connection, where the bonding leads of the cables' sheath bonding systems could reach lengths of up to 35 m due to land access limitations. • It could be concluded that the MTBF performance of a cable's bonding system strongly depends on a) the lightning performance of the connected overhead line(s) and b) the selected bonding scheme and its design. In mixed/Syphon connections, the cable system as a whole can be subjected to fast-front overvoltages due to lightning strikes, either directly on the phase conductors or on the shield wires of the overhead line(s) connected to the cable. In this paper, a methodology is presented that facilitates the calculation of the failure rate performance of a cable's sheath bonding system due to lightning strikes on the connected overhead line(s). [ABSTRACT FROM AUTHOR]