Measurement of transfer impedances of components for automotive high-voltage power networks

During the development of motor vehicles several Electromagnetic Compatibility (EMC) measures must be taken into consideration. Particularly when electrical drive systems are implemented, the electrical power train has to be designed for the transmission of high levels of electric power. The use of efficient power electronics causes electromagnetic disturbances which can influence other components in an undesirable way. An effective measure to suppress those interferences is shielding of cables and components of the power train. As a consequence it is necessary to qualify the shielding effectiveness by suitable measurements. In this contribution different measurement methods are investigated which can be used to measure the transfer impedance of cables and connector assemblies at lower frequencies. The focus is thereby on frequencies up to 100 MHz because the expected disturbances are in the frequency range of a few kilohertz up to several megahertz.