This paper exploits the three-dimensional (3D) parasitics cancellation techniques for EMI filters in Power Sandwich integrated construction. A Power Sandwich filter employs surface mount technology (SMT) compatible x-dimensional (x-dim) components which have the same height and double sided SMT electrical terminations. Thereby a 3D spatial components placement platform is provided. The 3D techniques which aim to canceling/reducing both mutual and self parasitics of the filter are proposed and followed by the experimental verifications. A cancellation turn is designed to reduce the self ESL of the x-dim SMT capacitors. The proposed techniques are applied to a LC CM filter for a motor drive. The filter equivalent circuit model that only includes the extracted components self parasitics is built, where the parasitics and mutual couplings effects are analyzed, the crucial couplings are identified. The techniques are verified through a variety of performed measurements which include both the insertion loss experiments from a network analyzer and spectrum measurements from a LISN in the operating motor drive system. The experimental results show that the proposed techniques significantly improve the filter performance in the high conducted frequency range.@en

This paper proposes a comprehensive EMI common-mode (CM) filter design procedure to suppress conducted EMI in silicon carbide (SiC) JFETs based inverter-fed motor drive systems. The first part of this paper is focusing on analyzing the EMC issue arisen from the newly generated power semiconductor device - SiC JFET, where the switching dynamics of SiC JFET and Si IGBT with the same power flowing level are compared. Then the second part towards EMI suppression for the inverter prototype. A comprehensive EMI CM filter design procedure is proposed. The proposed CM equivalent circuit model is able to evaluate the filter insertion loss gains over the whole conducted EMI frequency range, thereby different filter topologies can be compared and optimally selected. The performed experiments form the guideline that exhibits the process how the generated conducted EMI from the built inverter prototype is successfully suppressed to comply with the IEC61800-3 standard step by step.@en

This paper proposes a general device-based common mode (CM) model for inverter-fed motor system that able to describe the CM conducted electromagnetic interference (EMI) propagating mechanism in the system. Numerical parameters are derived using impedance measurements. The procedure of model elements extraction is introduced systematically and is convenient to implement. The derived model makes the CM EMI characteristic of the inverter is deduced from a circuit analysis viewpoint. Variable EMI noise propagation paths are evaluated and impedances along the propagation loops inside the inverter can be reconstructed for better EMI suppression. The transfer ratio calculations under different conditions show good agreement with experimental measurements verifying the proposed modeling methodology.@en