The Influence of Bond Wire Aging on DM EMI Noise in IGBT Converters Considering High-Frequency Ringing

This paper investigates the impact of bond wire aging on differential mode (DM) electromagnetic interference (EMI) noise emissions in IGBTs under the influence of high-frequency ringing. Using a DC-DC buck converter composed of an IGBT half-bridge module as an example, the study analyzes the changes in the EMI spectrum caused by bond wire lift-off in both the time and frequency domains. The paper explains the generation mechanism of high-frequency oscillations induced by the interaction between the stray inductance of the DC link and the freewheeling diode. The study reveals that bond wire lift-off alters DM EMI noise emissions by affecting the switching characteristics of the IGBT. Additionally, an increase in the number of lift-off bond wires during ringing significantly enhances DM EMI noise emissions at and above the resonance frequency. The findings of this study provide a new perspective on the aging effects of power electronic devices and their impact on EMI.