Fast Reconstitution Method (FRM) to Compute the Broadband Spectrum of Common Mode Conducted Disturbances

This paper deals with time domain simulation of common mode (CM) conducted disturbances in power electronics. This study proposes a proof of concept of a fast reconstruction method (FRM), which allows to compute the spectrum of a current based on the knowledge of a single pulse of current (i.e., the knowledge of the disturbances on a small fraction of time) and of the switching instants (i.e., the control strategy of the structure). The first parts of the paper demonstrate the reliability of the method using data measurements of a CM current generated by a PWM half-bridge converter and then by a three phase inverter. The simulation time saved thanks to the FRM is then quantified by comparing the simulation durations with or without using the FRM. In our example, the FRM allows to divide the simulation time by about 10. This analysis points out that the complex information of a CM current is contained in a small time interval. As a consequence the complete spectrum can be predicted with only a very fast simulation. The mathematical techniques developed here forecast promising reduction of simulation durations.