Conference Agenda

Electromagnetic (EM) design of electric vehicles (EVs) is of rising significance, since any limit violation of the EM interference (EMI) prohibits the EVs' road approval. The design for electromagnetic compatibility (EMC) of conducted emission (CE) can be stated as a multi-parametric optimization problem of Kirchhoff's Current Law (KCL), since CE tests rely on measured voltages instead of fields. Gaussian Process GP Regression is known to solve these problems. The high complexity of EV traction inverter models forces to use a minimal number of training data, which could be achieved by incorporating physical constraints. We present a GP model that obeys KCL, paving the way to design machine learning tailored to solve circuit-level EM problems.

The equivalence of working volumes (WV) in reverberation chambers (RCs) is investigated by the regime of state-of-the-art sensitivity analysis (SA) techniques by inspecting the effect of changing configuration parameters to the field uniformity (FU) in a frequency-dependent study close to the lowest usable frequency (LUF) under different loading conditions. The Sobol' indices as SA measures are evaluated at each stirrer step and frequency. For efficient calculation, different state-of-the-art surrogate modeling techniques were utilized to substitute the full-wave simulation model depending on the characteristics of the WVs. The computational expenses of the problem are further reduced by using a decreased number of stirrer steps and frequencies, which are achieved by means of adaptive sampling techniques through kriging interpolation. Furthermore, the size of the experimental design (ED) set, i.e., the number of different configurations is controlled by performing convergence studies. The proposed method is able to reconstruct the 2D sensitivity map of the configuration parameters as functions of the stirrer steps and the frequency with a fewer number of samples.

In order to analyze impact of sandstorms on the ion flow field around HVDC transmission lines, a modeling and calculation method for the ion flow field in the sandstorm environment is proposed in this paper. The forces, motion, and the charge effects of sand particles are incorporated into the ion flow field calculations with the upstream finite element method. After the model is validated against the experiment results, the charging characteristics of the sand particles and the ion flow field in the sandstorm environment are analyzed. This study is helpful to the design of HVDC lines in sandstorm-prone areas.

The modeling of electrical towers is fundamental to the assessment of electromagnetic transients caused by lightning in power systems. In this context, classical tower models without frequency-dependent effects are well studied in the literature. However, there are few studies on frequency-dependent effects, which have recently received a great deal of attention due to their specific characteristics. Frequency-dependent effects on tower systems are created by ground characteristics. In this paper, the overvoltage caused by an incident lightning strike at the top of a tower cascade is determined. The impedance and admittance of the whole system (tower, multiconductor line and tower grounding system buried in different homogeneous soils) are approximated by the vector fitting technique. The results obtained show a clear difference in the voltage response in the time domain for the different soil characteristics.

Electromagnetic absorbers are applied in multiple applications and therefore, are subjected to different constraints. In this paper the design of an electromagnetic absorber is tackled by a couple of hybrid quantum-classical optimization algorithms that overpass the performance of a generic genetic algorithm usually applied in these scenarios.

In this paper, we propose the modeling analysis of the transient behavior of the grounding circuits of a wind farm during a direct lightning strike. This modeling, in the time domain, is developed from the transmission line equations, the vector fitting technique, the FDTD numerical method and the electromagnetic topological formalism. This modeling simultaneously considers the dependence on frequency and the ionization of the ground which generally occurs during the injection of a high intensity current. We validate this modeling by measurement and we propose applications on grounding circuits used in wind farms.

When the electromagnetic radiation emitted by the lightning channel couples to the shields of overhead or buried cables, it induces large currents causing transient overvoltages between the internal conductors and the shield. These disturbances can alter the insulation of the cable and can cause the proper operation of the electrical devices connected to it. For the analysis by simulation of the electromagnetic coupling between a buried shielded cable and a lightning channel, this paper presents a modeling developed from the extended transmission line theory and the topological electromagnetic formalism. It also discusses the role of a bare shield wire buried parallel to the shielded cable to reduce these disturbances. We validate the modeling used by comparing our calculation results with those achieved by measurement and we propose some applications to highlight the role of the shielding wire in reducing the disturbances induced in the shielded cable.

Reliability of telecommunications and energy transport systems is principally based on the electrical state of cables and lines. Reflectometry, the basis of which is the analysis of an echo, is the most used in this case to characterize the link status which can be affected by various aggressions. In this paper, we propose a complete modeling which takes into account the propagation of a wave in a network of cables and the mathematical analysis of signals that may inform us about his condition. Our objective is to explain the origin of transient signals that may appear abnormally after mathematical analysis of the network response to an excitation. For the diagnosis of faults we use a parametric mathematical method, called windowed Pencil matrix, which allows a time-frequency analysis of the signals. This parametric representation allows us to determine the parameters describing a signal, a system or a process.

Compensation coils are used to mitigate magnetic fields as they are simple, efficient and generally low-cost. They produce a magnetic field that opposes the incident one. They are classified into passive coils, when there is no excitation, and active coils when there is independent excitation. Here we propose a new compensation coil configuration that combines the advantages of passive coils (no excitation) with those of the active coil (high performance) using a parallel connection of the shielding coil with the primary source coil.

This paper conducts a simulation analysis on the performance of magnetic shielding materials under different interference magnetic field intensities. A finite element model of the magnetic shielding structure is established within the context of actual distribution line current measurement environments. The finite element analysis results show that magnetic shielding significantly enhances measurement accuracy. At low interference levels, permalloy exhibits better magnetic shielding performance compared to silicon steel, while silicon steel proves more effective under higher interference levels. This study underscores the importance of selecting shielding materials and structures based on the measurement environment, offering valuable insights for optimizing current measurement in smart grids.

Embedded power electronics play a major role in automotive and aerospace. With proliferation of radiation sources, these sensitive power electronics needs to be protect against undesired signals that could cause malfunctioning. Shielding enclosures are used in this scope. For weight reasons, they use magnetic composite material in case of very low frequency and conductive composite material for frequency up to few dozens of kHz. For devices operating from 1 Hz to 1 MHz, using each kind of shielding material is not efficient. In this paper we study association of a magnetic composite material efficient at low frequency, to a conductive composite material efficient when frequency grows up to few dozens kHz. The resulting composite is efficient in the whole frequency range.

This paper presents an analytical solution for a two-dimensional structure consisting of long current-carrying lines within a rectangular, slotted duct, using the mode-matching method. The solution facilitates efficient and accurate calculation of leakage magnetic fields by accounting for enclosure and slot dimensions, as well as the number, magnitude, phase, and position of the current lines. Compared to numerical methods, the proposed series solution offers faster computation while maintaining accuracy and convergence, providing a robust tool for electromagnetic analysis.

High-voltage power-converter reliability in electric vehicles (EVs) is becoming increasingly important due to their rapid popularization. The DC-DC converter is a fundamental component of the EV power-conversion system, as it controls and supplies the voltage required by electronic devices using high-voltage battery sources. The converter significantly influences the vehicle's electrical efficiency and performance. Reliability issues caused by electromagnetic interference (EMI) between electronic devices are critical, as are driver safety concerns stemming from the use of high-capacity batteries. High-voltage DC-DC converters in EVs can be designed using various topologies. The LLC resonant topology enables zero-voltage switching (ZVS) and zero-current switching (ZCS), which minimize electrical losses in high-speed switching environments. This study analyzes the characteristics of EMI-conducted emission noise under ZVS operation and presents key factors for optimal noise-reduction design.