Accurate Multiport Network Model for Forced Oscillations Analysis and Suppression of Multichip IGBT Power Modules

In this article, a multiport network approach is proposed to analyze the forced oscillations issue for the multichips power module. First, experimental results indicate the presence of multiple resonance points caused by forced oscillations during the switching process of multichip power modules. Due to the complex distribution of parasitic parameters within the module, it is challenging to establish an accurate analytical model. Therefore, this article proposes a method based on multisoftware collaborative simulation to extract the corresponding impedance of different chip ports. In addition, the impact of bus parasitic inductance and chip capacitances on port impedance is obtained. Compared with the experimental result, the error of dominant frequency obtained by the proposed model is less than 3%. Furthermore, the sensitivity of the spatial near-field spectrum to bus voltage and load current is studied based on experimental results. Finally, the suppression methods for forced oscillations are proposed based on the aforementioned theoretical analysis from the perspectives of both chips and packaging. The effectiveness of proposed methods is verified through experimental results.