Estimation of multi-conductor underground cable parameters from measurements

This paper describes the method of estimating the underground cable multi-conductor parameters from measurements of voltage and current magnitudes and phase angles at the two ends of the cable. This becomes necessary to determine if an underground cable needs replacement due to changes in the cable parameters due to ageing. A single cable consisting of core and sheath in a 275 kV system is considered and the cable parameters determined from the cable dimensions, material properties and the earth conductivity. The method of evaluating the multi-conductor cable parameters from measurements is then described.