Wide band measurements in time domain with current and voltage probes for power losses evaluation and EMC measurements on power converters

Current and voltage signal must be correctly measured in order to evaluate accurately power losses and electromagnetic interferences in time domain. This paper proposes a way to compensate the measured signals using the gain of the probes and an evaluation of the Common Mode Rejection Ratio of the differential voltage probe. Deconvolution shows its efficiency: the shape of the signal and the phase shift between current and voltage after compensation allow an accurate measurement of the power losses. Common Mode Rejection Ratio estimation shows that it is constant for the studied amplitude levels and there is low impact on the differential voltage measurements.