Characterization and selection of electromagnetic interference (EMI) line filter for Variable-Frequency Drive (VFD) application

This study investigates conductive interference in a low-power variable-frequency drive (VFD). The VFD generates high-frequency voltage harmonics at 16 kHz and 24 kHz. A suitable commercial electromagnetic interference (EMI) line filter is identified, which effectively reduces the amplitudes of these harmonic voltages. A simulation model of the EMI line filter is developed to analyze its common-mode and differential-mode noise attenuation properties in greater detail. The simulation results confirm the filter's suitability for this specific VFD application. The filter's performance is further validated through experimental measurements. In conclusion, a simple step-by-step guideline for EMI filter selection is proposed. The findings of this study may also serve as a foundation for educational material for undergraduate students, with several potential practical exercises developed based on this work.