Black Box Approach to Active Impedance Characterization of Automotive Components

Electromagnetic interference (EMI) of automotive components is evaluated by testing in a test setup that emulates the vehicle environment. Nevertheless the real vehicle environment differs from the test setup. This results in a deviation of the component behavior during testing and in the target vehicle. To avoid redesign in late development stages the disturbance behavior of components must be characterized early on. A characterization can be obtained by modeling the component as a Thevenin equivalent disturbance source. A key aspect of this approach is the determination of the internal impedance of the component in active mode.