Estimation of Inverter EM Noise Propagation to Network Communication through Wire Harnesses

The electro-magnetic noise generated in an HV inverter can be a significant side-effect when it interferes with automotive LAN communications. This paper provides a calculation method to estimate the spectrum of the noise propagating through the wire harnesses by modeling LAN wire harnesses as uniform multi-conductor transmission lines and ECUs as S-parameter elements. Applying this model to a test bench with actual automotive ECUs, the consistency of the calculation and actual measurement is evaluated. The calculated noise spectrum peaks agree with the measured noise spectrum peaks with a tolerance of 6dB within the frequency range below 20MHz