High-Frequency Behavioral Modeling of Inverter-Fed Motor Drives for EMI Analysis

This paper introduces a measurement-based black-box modeling approach for predicting conducted EMI on the motor side of inverter-fed drives. Converter impedances, noise sources, cable RLGC parameters, and a synchronous machine behavioral model are identified from terminal measurements and implemented in LTspice for time-domain simulation. The framework inherently accounts for PWMinduced nonlinearities, accurately reproducing spectral envelopes and resonances up to 100 MHz. Validation on a 6 kW drive demonstrates close agreement between simulated and measured common-mode and differential-mode currents, enabling systematic motor-side EMI filter design.