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Borrelia surface proteins: new horizons in Lyme disease diagnosis
No full textInternational audienceSpirochetes of the genus Borrelia are the causative agents of vector-borne diseases, including Lyme borreliosis (LB). Clinical LB diagnosis is challenging due to the heterogeneous and nonspecific symptoms among patients further complicated by the potential for co-infection with Borrelia species and other pathogens. Current diagnosis is based on an indirect serological approach with limitations such as early-stage low sensitivity and cross reactivity. This review explores the potential of Borrelia surface proteins as biomarkers for a more accurate diagnosis of LB, with a particular interest in proteins involved in (i) tissue adhesion, essential for host colonization, (ii) antigenic variation, and (iii) immune evasion. By detailing the role of the distinct surface proteins, the review highlights their potential as biomarkers in order to improve the detection of LB, particularly in the early stages. In addition to their diagnostic value, they also represent potential targets for the development of new therapeutic strategies. Keypoints• Various Borrelia surface proteins drive host colonization and immune evasion.• Novel bacterial proteins biomarkers are needed for improved diagnosis and therapy.• State of the art on Borrelia surface proteins and their associated role.</div
Overview, Comparison and Extension of Concepts for Current-Controlled, Adjustable Inductances
No full textInternational audienceMagnetic components are an important part of many DC/DC converters. The use of active premagnetization makes them adjustable, which means an additional degree of freedom in the design of the respective converter topology. However, when selecting the most suitable premagnetization method for the specific application, various impact factors should be taken into account to ensure an optimal design. This paper presents, analyses and discusses impact factors such as the adjustability range of the inductance value, the magnetic feedback as well as the behaviour of the auxiliary circuit for different premagnetization methods and different inductor design approaches. The measurement verification was carried out using a buck converter
Design and Evaluation of Single-Active Bridge Configurations for Optimal Megawatt Charging Systems
No full textInternational audienceThe increasing demand for highperformance isolated DC-DC converters is particularly evident in the domains of charging infrastructure and electromobility. Among various converter topologies, the Single-Active Bridge (SAB) stands out as a preferred choice for applications requiring unidirectional power flow. This preference is driven by the SAB's inherent simplicity, robustness, and ease of control. The paper explores multiple configurations of the SAB architecture [1]. A prototype is developed to validate the features and the design procedures presented in this paper. This paper summarizes testing and analysis, to evaluate the performance of each configuration to identify the optimal design for an efficient and reliable high-power charging system. The results offer valuable insights for developing advanced MCS solutions, ensuring robust and efficient energy transfer in high-demand scenarios. Ultimately the SAB configuration is loaded at 88 % of the nominal load and the results are showcased
MMC-Autotransformer : Impact of the Control on the Design and Efficiency
No full textInternational audienceTo increase flexibility and reliability of HVDC links and MTDC, it is likely that DC-DC converter will be employed. This paper specifically focuses on the DC-Auto-transformer. This study investigates its performance in relation to its parameters including: AC voltages, frequency and waveform characteristics. The analysis presented in this paper demonstrates that increasing the AC voltage within the converter reduces losses and minimizes capacitor size requirements. While, increasing the frequency reduces the losses as well as required size of capacitors. Furthermore, the results indicate that adopting a trapezoidal waveform improves both efficiency and capacitor size
Comparative Stability Study of a Dual Active Bridge-Based Battery Charger With Advanced Modulation Schemes
No full textInternational audienceThanks to their galvanic isolation and bidirectional power transfer features, the Dual Active Bridge (DAB) converters can offer a promising solution for interconnecting battery chargers to emerging DC grid applications. When cascaded with LC filters, the charger stability can be affected by the impedance interactions caused by the closed-loop charging process. This is exacerbated by the wide range of operating points in terms of DC voltages as well as the numerous Modulation Schemes (MS). To address this, the current paper extends the averaged smallsignal model to the case of a Constant Current Constant Voltage (CC-CV) charging process. A stability analysis method is proposed to compare Single, Extended, Dual and Triple Phase Shift MS during a charging cycle. Simulation results validate the proposed models and highlight the flaws of advanced MS under varying operating conditions
A Compact Dual-Band Wireless Power Transfer System Based on Circular Edges with DGS Resonators
No full textInternational audienceThe present study deals with the design of a dualband wireless power transfer (WPT) system using Defected ground structure (DGS) model resonators. The most important factor will be achieving high conversion efficiency while keeping its structural dimensions small. To improve transmission efficiency and minimize return losses and insensitivity to mismatch between resonators at their resonance frequencies, we introduce a gap in the ground layer. For the proposed system, the transmission power efficiency at frequencies of 330 and 770 MHz is 92.5% and 84.6%, respectively, the simulation results from both CST and ADS software are closely aligned. Also, the figure of merit (FoM) derived from the simulation results is 0.78 and 0.72 at respective resonance frequencies
High-Power 4500 V 5000 A Press Pack IGBTs for HVDC Solid-State Circuit Breaker Application
No full textInternational audienceLow Temperature Sintered Press-pack IGBTs (PPI) outperform modules, offering improved cooling efficiency, reliability, and significantly higher-current handling. A single 4500 V, 5000 A PPI is designed to withstand 20-30 kA DC system short-circuit currents for 150 ms, making PPI a robust and space-saving choice for solid-state DC breaker applications
PatchTrAD: A Patch-Based Transformer focusing on Patch-Wise Reconstruction Error for Time Series Anomaly Detection
No full textInternational audienceTime series anomaly detection (TSAD) focuses on identifying whether observations in streaming data deviate significantly from normal patterns. With the prevalence of connected devices, anomaly detection on time series has become paramount, as it enables real-time monitoring and early detection of irregular behaviors across various application domains. In this work, we introduce PatchTrAD, a Patch-based Transformer model for time series anomaly detection. Our approach leverages a Transformer encoder along with the use of patches under a reconstructionbased framework for anomaly detection. Empirical evaluations on multiple benchmark datasets show that PatchTrAD is on par, in terms of detection performance, with state-of-the-art deep learning models for anomaly detection while being time efficient during inference
Analysis of Aged Power Modules considering the Loss Calculation of a Heavy-Duty Fuel Cell Truck
No full textFor this work, I would like to extend my gratitudeto the Advanced Engineering department ofMercedes-Benz Trucks for providing the realmeasured data of a Heavy-Duty Fuel Cell Truck,which made this analysis possible.International audienceThe aging of power modules in Heavy-Duty Fuel Cell Trucks (HDFCT) is crucial because, as these modules age, their on-state resistance increases. This increase results mainly in higher switching and conduction losses in case of a Si IGBT, ultimately reducing the efficiency of the truck. This work presents the results of simulated switching and conduction losses based on a real mission profile using actual measured (aged) devices. These devices exhibit varying on-state resistances
Backstepping Controller Design with Inherent Current Limitation for a Voltage-Controlled Grid-Side Converter
No full textInternational audienceThe control and optimization of gridforming converters remain crucial in power electronics research. A key challenge is limiting the converter's output current during severe grid disturbances to protect equipment. Existing current-limiting strategies either indirectly modify the output voltage or directly control the current, the latter requiring an additional control loop that increases complexity and may introduce instability. To address these challenges, this paper proposes a backsteppingbased control strategy that ensures asymptotic stability while maintaining current limitation. A novel selection of control Lyapunov functions enables a continuous control law, ensuring seamless operation across normal and fault conditions without switching between control modes. This feature is particularly beneficial for stability analysis of power electronic-based grids under fault conditions, as it allows for a more straightforward and unified stability assessment. The proposed method is implemented on a two-level voltage source converter (2L-VSC) with an LCL filter. Preliminary simulations validate its effectiveness in ensuring stable operation under both nominal and fault conditions