What if we model the cable as a flat ribbon?

Modeling the Powerbus and Cable with Microstripes

An 8-mm wide ribbon can be used to model the cable. This allows the cable to connect to the edge of the plane. The results shown in Figures 1 - 3 show that this substitution is acceptable. (These simulations were done with a lossless dielectric.) Using a ribbon to represent the cable decreased the simulation time to about 4.5 hours.

Fig. 1. E-field at r = 10m, θ=90^°, φ=0^°; Red (round wire), Black (ribbon)

Fig. 2. E-field at r = 10m, θ=90^°, φ=90^°; Red (round wire), Black (ribbon)

Fig. 3. E-field at r = 10m, θ=0^°, φ=0^°; Red (round wire), Black (ribbon)