Research and Modeling on the Characteristic Changes of EMI Filter Passive Components under the Influence of Aging

At present, the power density of power electronic devices in data centers and electric vehicles is constantly increasing, and numerous electronic components are concentrated in a tight, high-temperature environment, which aggravates the performance degradation of electronic components. Consequently, X and Y capacitors, common-mode inductors, and differential-mode inductors used for electromagnetic interference (EMI) suppression suffer from aging effects, and their performance continues to decline. However, the electromagnetic compatibility test is often conducted immediately after the power electronic equipment leaves the factory. The electromagnetic compatibility of power electronic equipment is affected by aging, which is not assessed in current industrial testing. This study conducts aging experiments on passive electronic components in EMI filters and measures the impedance in the frequency range from 150 kHz to 30 MHz. Subsequently, a multi-element aging model based on electromagnetic field analysis is established. The proposed model is suitable for electromagnetic compatibility analysis considering aging. Finally, the aging performance of a commercial two-stage EMI filter is predicted to verify the model proposed in the study. The proposed model explains the degeneration of the EMI filter with aging in the frequency range of 150 kHz to 1 MHz, with a maximum amplitude error of 0.58 dB and phase error of 1.0°.