Underground cables typically represent assets that carry an elevated risk within the distribution system when compared to other distribution system assets. There are limited inspection and maintenance practices that can be actively performed for underground cables to further extend their useful life, due to the fact that these cables are typically contained underground – either direct-buried or in conduit – and possess limited accessibility. Furthermore, the outright replacement of cable segments can be very cost intensive for a utility to execute. There exists a need for a guide to be provided that can inform utilities using a practical framework for modelling their underground cable assets to improve upon the otherwise simple asset management strategies currently available.
Research was conducted into the various viable mathematical modelling techniques that could be applied to underground cable asset data in order to model failure rates. North American distribution utilities were surveyed to define the current state of data collection, failure rate modelling, and asset management strategies being utilized. Knowledge of the current utility practice was leveraged, in conjunction with knowledge of the available mathematical modelling approaches, to create an appropriate guide to fulfill the need within the distribution utility sector to better manage their underground cable assets in an effort to maximize cost benefits and reliability.
Underground Cable, XLPE, TRXLPE, PILC, Direct-Buried, Asset Management, Failure Rate Modelling, Statistical Model, Weibull Distribution, Exponential Distribution, Survival Analysis, Parametric Model, Reliability