The spread of information-communication technology (ICT) devices in full and/or hybrid electric vehicles is posing increasing issues about coexistence between communication and electric power systems. Particularly, under different operating conditions, the time-variant and nonlinear behavior of the involved power-electronic devices may cause detrimental electromagnetic interference (EMI) effects for onboard ICT devices. The use of passive or active EMI filters can mitigate EMI, yet their effective design requires the knowledge of the actual modal impedances of the involved components. With the final objective to support EMI filter design, in this work, the frequency response of the common mode (CM) and differential mode (DM) impedances of a complete automotive power train is investigated under different operating conditions. Moreover, both low-frequency functional aspects and high-frequency parasitic effects are considered and modelled properly.

The use of power electronic converters to interface renewable sources and intelligent loads to electricity distribution systems is increasing at a rapid rate as they bring flexibility and control to the system. However, they also bring an increased level of conducted emissions (CE) to the system due to their switching behaviour -usually at a few tens of kilohertz. The increased emissions are seen particularly in the low-frequency range (2-150 kHz) and it may possibly impair the operation of information and communication technology (ICT) equipment connected to the same system. It is therefore essential to assure accurate measurement of low frequency emissions from a particular piece of equipment, to ensure it meets standards for electromagnetic compatibility (EMC). According to EMC standards, CE are usually measured by using a Line Impedance Stabilization Network (LISN). However, the standard LISN bandwidth does not fully cover this low-frequency range (2-150 kHz), resulting in inaccurate measurement and poor repeatability. This paper examines this issue, by investigating the limitations in using the CISPR 16-1-2 LISN topology for CE measurement at low frequency in a grid-tied inverter system, and by proposing a possible solution, which requires adding extra components to the LISN circuit.

Electromagnetic fields of a 3-phase induction motor, i.e., electric and magnetic fields and current density, are highly influenced by its geometry, conductor material (conductivity, magnetic permeability, electric permittivity, and nonlinearity), and boundary conditions applied (interface between conductors and dielectrics). Through Finite Element Analysis (FEA), the behavior of electromagnetic fields can be predicted. Thus, favoring the electromagnetic interference mitigation techniques of the 3-phase induction motor. Therefore, this paper presents numerical modeling with FEA, based on COMSOL, as an early pre-compliance tool to investigate the current density distribution and electric and magnetic fields. The validation of the modeling approach will be presented and discussed considering a 3-phase induction motor. Furthermore, CISPR 25 will be considered to evaluate the interactions between electric and magnetic fields, current density distribution, and skin effect on an increasing frequency.

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This paper investigates the beneficial effects of Random Modulation strategies in reducing the conducted emissions generated by DC-DC converters. The analysis is carried out by PSpice-Simulink co-simulation in order to achieve effective modelling of the converter on the one hand (PSpice), and easy implementation of the modulation scheme on the other (Simulink). Particularly, Random Pulse Width Modulation is used to control a DC-DC converter involving second-generation Cree SiC MOSFET. The non-linear characteristics of the converter as well as its parasitic elements are considered by the PSpice model. The predicted CM and DM emissions are compared versus those obtained by standard PWM, showing a significant reduction of the overall emissions in the frequency range of interest.