Experimentally Validated Modular-Terminal-Behavioural Modelling of Conducted EMI in Full-Bridge Inverters

This paper presents a compact and experimentally validated methodology for modelling conducted Electromagnetic Interference (EMI) in full-bridge inverters, based on the Modular-Terminal-Behavioural (MTB) equivalent source approach. Unlike conventional modelling strategies that rely on detailed structural descriptions or computationally expensive electromagnetic simulations, the MTB model characterizes EMI sources purely in terms of their terminal behaviour. This black-box representation offers significant advantages in simplicity, scalability, and integration into system-level analyses. The proposed framework accurately predicts both Common-Mode (CM) and Differential-Mode (DM) conducted emissions over a wide frequency range, providing an efficient tool for Electromagnetic Compatibility (EMC) evaluation in power electronic systems. The methodology is experimentally validated using a full-bridge inverter prototype operating under realistic switching conditions. Norton-equivalent representations are extracted through nominal and attenuated test configurations, enabling the identification of EMI source currents and impedances without requiring intrusive open- or short-circuit assumptions. The resulting MTB model demonstrates strong agreement with Line Impedance Stabilization Network (LISN) measurements, with prediction errors remaining within ±3 dBµV across the 150 Hz – 30 MHz spectrum. The results confirm that CM emissions dominate in the mid-to-high frequency range, while DM contributions prevail at lower frequencies, highlighting the distinct propagation mechanisms involved. Beyond predictive accuracy, the MTB approach offers strategic benefits, including reduced computational overhead, adaptability to other converter topologies, and suitability for early-stage EMC compliance assessment. This makes it particularly valuable for industrial applications where fast design iterations and cost-effective EMI mitigation strategies are essential. Ultimately, this work bridges the gap between analytical EMI source modelling and practical validation, contributing a robust, generalizable framework for conducted EMI characterization in inverter-fed systems. Future extensions may focus on radiated EMI prediction and the integration of data-driven techniques for real-time EMC diagnostics.