Transmission Factor Measurement Based Impedance Characterisation Utilising a Double Current Probe Assembly

For efficiency reasons the power electronic devices of future aircrafts will be most likely equipped with fast switching semiconductors which will be challenging in terms of EMC compliance. The knowledge of the high frequency behaviour of the implemented system components would support innovative and also efficient EMI suppression techniques. Calibrated impedance probes can be used to examine the HF properties of built-in devices contactlessly. However DC or low frequency currents lead to saturation effects in the impedance probe's core, which distorts the measurement results. In this contribution two classic EMC current probes in combination with an in-situ calibration technique are utilised to perform contactless impedance measurements in the presence of DC bias currents.