Measurement of resistance characteristics of power cables in the very high frequency band for improving electromagnetic interference analysis

This paper focuses on the resistance characteristics of power cables in the very high frequency (VHF) band. The resistance characteristics have a significant influence on radiative electromagnetic interference (EMI). However, to the authors' knowledge, as yet there have been no reports regarding the resistance characteristics of power cables in the VHF band. This paper proposes a measurement method based on distributed constant circuit theory and impedance matching theory. By using this method, the resistance characteristics for a single-core wire with polyvinyl chloride insulation are measured in the frequency range from 10 to 100 MHz. The experimental results show that the measured values of the cable resistance are more than 10-fold the theoretical values calculated by taking the skin effect into account, which are often used in EMI analysis and simulation. Furthermore, the measured values are proportional to the frequency raised to a power of approximately 2/3, whereas the theoretical values are proportional to the square root of the frequency. The measured resistance is validated by simulation using the 3D electromagnetic analysis software EMC Studio.