Modeling of switching transients for frequency-domain EMC analysis of power converters

Abstract

Since the early 1990's, electrical energy tends to replace pneumatic and hydraulic energy aboard aircrafts. This is lead by MEA project and allows to reduce weight and volume of the actuators. But an increase of onboard electric energy leads to EMI issues. To comply with EMC standards, an EMI filter is often added to the electrical systems. In order to reduce the weight and volume impact of EMI filters, it is interesting to perform an optimization of the embedded electrical system at the design stage, based on EMC criteria, using a simulation approach. In order to perform these simulations, HF model of the system is necessary. Two approaches exist: either time-domain or frequency-domain simulations, each one having advantages and drawbacks. This paper presents a frequency-domain modeling method. The proposed method is based on the use of two linear equivalent noise generators topologies. The results obtained with the two topologies are combined, to obtain a good representation of power converters. This method increase the validity range of the simulation above 30MHz.