Characterization of radiated emissions from power electronic devices: synthesis of an equivalent model from near-field measurement

The paper presents an efficient methodology to characterize electromagnetic disturbances radiated from power electronic devices. The approach is based on the substitution of an equivalent set of elemental magnetic dipoles for the real system; this set radiates the same near-field. The cartography of the magnetic field obtained with a measurement bench gives these dipoles. The moments of the dipoles are determined through a root mean squared procedure; this procedure fits the measured field to the theoretical field over a closed surface surrounding the device under test. The viability of the approach is demonstrated on two circuit boards. The first one is a canonical configuration involving two solenoidal inductors. The second one is a practical power electronic converter. Comparisons between numerical and experimental magnetic field distributions underline the ability of the equivalent model.