Electric Fields Induced by Water Movement in Proximity to HVDC Submarine Cables

With the raised investment in interconnectors and offshore wind farms located further from the shore, there has been an increased need for the licensing and environmental assessment of high voltage direct current (HVDC) submarine cables. The motionally induced electric fields due to HVDC submarine cables have not been previously modeled in the literature. In this article, a methodology for modeling this phenomenon is outlined. Factors, such as geographical location of the cable system, electrical conductivities of the media, reference frames, and water velocity profile, are included in the analysis. The results are compared with an approximation adopted in other publications. The resulting electric fields and their spatial distributions are presented and discussed for different cable systems, cable orientations and reference frames. The dependency of the local electric fields on the geographical location is shown. The investigation demonstrates the sensitivity of electric fields to variations in seabed and water conductivities. Specifically, the most extreme combination yielded an 85<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\%$</tex-math></inline-formula> increase compared to the case with equal conductivities, which emphasises the substantial impact of media conductivities on local electric field prediction. The methodology outlined in this paper can provide a basis for future empirical validation, and inform biological experiments and licensing processes.