Magnetic field penetration into a slot on conducting plate and rectangular enclosure by long cables carrying currents

This paper presents an analytical method based on the Fourier transform and mode-matching technique to evaluate electromagnetic field leakage from long power cables. The proposed method models the two-dimensional transverse cross section of high-power cables and accurately predicts the effects of slot size, slot position, enclosure dimensions, and multiple cable configurations on low-frequency magnetic field penetration. The analytical results show excellent agreement with three-dimensional full-wave simulations for long yet finite cable cases, while requiring significantly less computation time. This approach provides clear quantitative insight into the relationship between structural parameters and field penetration, facilitating the efficient design and optimization of low-frequency magnetic shielding structures.