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At least 91 records · Page 5

Numerical and Experimental Modeling of the Recirculating Melt Flow Inside an Induction Crucible Furnace

In the paper, a new water model of the turbulent recirculating flow in an induction furnace is introduced. The water model was based on the principle of the stirred vessel used in process engineering. The flow field in the water model was measured by means of particle image velocimetry in order to verify the model’s performance. Here, it is indicated that the flow consists of two toroidal vortices similar to the flow in the induction crucible furnace. Furthermore, the turbulent flow in the water model is investigated numerically by adopting eddy-resolving turbulence modeling. The two toroidal vortices occur in the simulations as well. The numerical approaches provide identical time-averaged flow patterns. Moreover, a good qualitative agreement is observed on comparing the experimental and numerical results. In addition, a numerical simulation of the melt flow in a real induction crucible furnace was performed. The turbulent kinetic energy spectrum of the flow in the water model was compared to that of the melt flow in the induction crucible furnace to show the similarity in the nature of turbulence.

36 MATERIALS SCIENCE↗

Metal-metal interaction mediates the iron induction of Drosophila MtnB

Metallothionein (MT) protein families are a class of small and universal proteins rich in cysteine residues. They are synthesized in response to heavy metal stresses to sequester the toxic ions by metal-thiolate bridges. Five MT family members, namely MtnA, MtnB, MtnC, MtnD and MtnE, have been discovered and identified in Drosophila. These five isoforms of MTs are regulated by metal responsive transcription factor dMTF-1 and play differentiated but overlapping roles in detoxification of metal ions. Previous researches have shown that Drosophila MtnB responds to copper (Cu), cadmium (Cd) and zinc (Zn). Interestingly in this study we found that Drosophila MtnB expression also responds to elevated iron levels in the diet. Further investigations revealed that MtnB plays limited roles in iron detoxification, and the direct binding of MtnB to ferrous iron in vitro is also weak. The induction of MtnB by iron turns out to be mediated by iron interference of other metals, because EDTA at even a partial concentration of that of iron can suppress this induction. Indeed, in the presence of iron, zinc homeostasis is altered, as reflected by expression changes of zinc transporters dZIP1 and dZnT1. Thus, iron-mediated MtnB induction appears resulting from interrupted homeostasis of other metals such as zinc, which in turns induced MtnB expression. Metal-metal interaction may more widely exist than we expected. - Highlights: • Metallothionein B expression is regulated by iron in Drosophila melanogaster. • MtnB has limited physiological roles in iron detoxification. • Binding affinity of MtnB to iron is weak in vitro. • Induction of Drosophila MtnB by iron is mediated indirectly through metal-metal interaction.

60 APPLIED LIFE SCIENCES↗

A Phase 2 Open Label, Single-Arm Trial to Evaluate the Combination of Cetuximab Plus Taxotere, Cisplatin, and 5-Flurouracil as an Induction Regimen in Patients With Unresectable Squamous Cell Carcinoma of the Head and Neck

Purpose: Despite treatment, prognosis of unresectable squamous cell carcinoma of the head and neck (SCCHC) is dismal. Cetuximab therapy has proven to increase the clinical activity of radiation therapy and chemotherapy in patients with locoregional advanced disease with an acceptable toxicity profile. We designed a phase 2 trial to evaluate the efficacy of docetaxel, cisplatin, and 5-fluorouracil (TPF) plus cetuximab (C-TPF) as an induction regimen in patients with unresectable SCCHN. Methods and Materials: A single-arm phase 2 trial was conducted. Eligible patients included those with untreated unresectable SCCHC, World Health Organization performance status of 0 to 1, 18 to 70 years of age. Treatment consisted of four 21-day cycles of TPF (docetaxel, 75 mg/m{sup 2} day 1; cisplatin, 75 mg/m{sup 2} day 1; 5-fluorouracil [5-FU], 750 mg/m{sup 2} day 1-5) and cetuximab, 250 mg/m{sup 2} weekly (loading dose of 400 mg/m{sup 2}). Prophylactic granulocyte colony-stimulating factor and antibiotic support were given. After induction, sequential accelerated radiation therapy with concomitant boost (69.9 Gy) and weekly cetuximab therapy were delivered in the absence of disease progression. The primary endpoint was objective response rate (ORR) to C-TPF. Results: Fifty patients were enrolled across 8 centers. Median age was 54 years; disease was stage IV; oropharynx and hypopharynx were the most common primary sites. Eighty-two percent received 4 cycles of C-TPF, and 86% started sequential treatment based on radiation therapy and cetuximab. ORR after C-TPF was 86% (95% confidence interval [CI]: 73%-94%) and 24% had complete response (CR). With a median follow-up of 40.7 months, median overall survival (OS) was 40.7 months. The 2-year actuarial locoregional control (LRC) rate was 57%. The most common drug-related grade 3 or 4 toxicities during induction were neutropenia (24%), neutropenic fever (24%), and diarrhea (20%). There were 3 treatment-related deaths (6%). Conclusions: C-TPF yields high ORR and CR as induction treatment in unresectable SCCHN. However, hematologic toxicity is too high to recommend this regimen at the current dose.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Induction-detection electron spin resonance with spin sensitivity of a few tens of spins

Electron spin resonance (ESR) is a spectroscopic method that addresses electrons in paramagnetic materials directly through their spin properties. ESR has many applications, ranging from semiconductor characterization to structural biology and even quantum computing. Although it is very powerful and informative, ESR traditionally suffers from low sensitivity, requiring many millions of spins to get a measureable signal with commercial systems using the Faraday induction-detection principle. In view of this disadvantage, significant efforts were made recently to develop alternative detection schemes based, for example, on force, optical, or electrical detection of spins, all of which can reach single electron spin sensitivity. This sensitivity, however, comes at the price of limited applicability and usefulness with regard to real scientific and technological issues facing modern ESR which are currently dealt with conventional induction-detection ESR on a daily basis. Here, we present the most sensitive experimental induction-detection ESR setup and results ever recorded that can detect the signal from just a few tens of spins. They were achieved thanks to the development of an ultra-miniature micrometer-sized microwave resonator that was operated at ∼34 GHz at cryogenic temperatures in conjunction with a unique cryogenically cooled low noise amplifier. The test sample used was isotopically enriched phosphorus-doped silicon, which is of significant relevance to spin-based quantum computing. The sensitivity was experimentally verified with the aid of a unique high-resolution ESR imaging approach. These results represent a paradigm shift with respect to the capabilities and possible applications of induction-detection-based ESR spectroscopy and imaging.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

Coupled Induction Machine and HVAC Models for Simulating HVAC Performance Considering Grid Dynamics in Buildings

This paper presents the development of novel models that integrate induction machines with HVAC equipment, such as pumps, heat pumps, and chillers, to analyze the impact of electrical parameters on the operational performance of thermo-fluid systems. The proposed model employs a coupling technique that captures the dynamic interactions between induction machines and HVAC systems. By integrating electrical, thermal, and mechanical dynamics, the models provide a comprehensive framework for simulating real-world scenarios, including interactions with the electrical grid. This achievement was made possible through the development of a Computationally Efficient and Accurate Induction Machine (CEAIM) model. Implemented using the equation-based Modelica language, the CEAIM model has been validated against experimental results, manufacturer data sheets, and various operating conditions. Its performance has been compared with existing induction machine models in the Modelica Standard Library (MSL), demonstrating superior accuracy and computational efficiency. The CEAIM model predicts torque, speed, and power consumption with a coefficient of determination (R 2 ) ranging from 0.98 to 1 and a coefficient of variation of root mean square error (CVRMSE) between 0.27% and 6.67%. Additionally, CEAIM scales more efficiently than conventional MSL models, with a slower computational growth rate in large-scale simulations. After thorough validation of the CEAIM model, it was coupled with HVAC equipment as this approach provides a detailed multi-dimensional view of capturing electrical transients and mechanical performance. To support this, a case study was conducted to showcase its capabilities.

24 POWER TRANSMISSION AND DISTRIBUTION↗

Analysis and Experimental Evaluation of Middle-Point Inductance's Effect on Switching Transients for Multiple-Chip Power Module Package

Middle-point inductance L middle can be introduced in multiple-chip power module package designs. In this paper, the effect of middle-point inductance on switching transients is analyzed first using a frequency-domain analysis. Then a dedicated multiple-chip power module is fabricated with the capability of varying L middle , and extensive switching tests are conducted to evaluate the middle-point inductance's impact. Experiment result shows that the active MOSFET's turn-on loss decreases at higher values of L middle , while its turn-off loss increases. Detailed analysis of this loss variation is presented. In addition to the switching loss variation, it is also observed that different peak voltage stresses are imposed on the active switch and antiparallel diode during the switching transients. Specifically, in the case of lower MOSFET's turn-off, the maximum voltage of the lower MOSFET increases as L middle goes up; however, the peak voltage of the antiparallel diode decreases significantly. Furthermore, the induced voltage spikes during upper MOSFET turn-on process is also evaluated, and an opposite trend is observed experimentally. Analysis of the voltage overshoot variation is discussed. Based on the experimental evaluation and analysis, a multiple-chip power module package design guideline is summarized considering the middle-point inductance's effect.

42 ENGINEERING↗

On the Inductance of a Single-Channel Spark-Gap Switch for Pulsed Power Applications

In this paper, we derive an alternative expression for calculating the inductance of a single-channel spark-gap switch. We believe this new inductance expression provides greater clarity compared to other approaches. Interestingly, both the Rosa formula and the coaxial inductance formula, which are commonly used in such calculations, emerge as special cases of our new expression. To validate the proposed formula, we conducted COMSOL simulations that show excellent agreement with our theoretical predictions.

COMSOL↗

Induction of α6 and β1 integrins by acupuncture stimulation in rats

Acupuncture therapy is performed by applying the needle insertion at discrete cutaneous locations and used for the treatments of diverse symptoms and disorders. In order to elucidate mechanistic basis on how acupuncture stimulation (AS) produces therapeutic effects, it is primarily important to understand tissue responses locally at the acupuncture site (acupoint). Here, we investigated integrin protein as molecular target responding to and integrating AS. Signals of α6 and β1 integrins were clearly induced at zusanli acupoint 24 h after AS in areas of nuclear clusters around the needle track. Induction levels of integrin were largely reduced by needle insertion at non-acupuncture point or without needle rotation. Phospho-Erk1/2 was initially decreased below the basal level after AS but increased 24 h later. Induction pattern of phospho-Erk1/2 was as similar as that of α6 integrin in its selectivity to needling procedure and tissue distribution. We further found that mRNA expression of P2X3 purinergic receptor was upregulated in the dorsal root ganglion (DRG) after AS, but decreased by the inhibition of Erk1/2 activity at the acupuncture area. Moreover, AS-mediated integrin activation was required for Erk1/2 activation at the acupuncture site and regulation of pain sensitivity in the hind paw. The present results provide a new evidence on acupuncture-specific tissue response in terms of integrin induction, and further suggest that integrin activation may be involved in transmitting mechanosensory signals from the acupoint to afferent nerve fiber. - Highlights: • We investigated local tissue responses after acupuncture stimulation (AS) in rats. • AS strongly induced α6 and β1 integrins and activated Erk1/2. • Integrin Induction was primarily specific to acupuncture site and needle rotation.

60 APPLIED LIFE SCIENCES↗

Concurrent Chemo-Radiation With or Without Induction Gemcitabine, Carboplatin, and Paclitaxel: A Randomized, Phase 2/3 Trial in Locally Advanced Nasopharyngeal Carcinoma

Purpose: To compare survival, tumor control, toxicities, and quality of life of patients with locally advanced nasopharyngeal carcinoma (NPC) treated with induction chemotherapy and concurrent chemo-radiation (CCRT), against CCRT alone. Patients and Methods: Patients were stratified by N stage and randomized to induction GCP (3 cycles of gemcitabine 1000 mg/m{sup 2}, carboplatin area under the concentration-time-curve 2.5, and paclitaxel 70 mg/m{sup 2} given days 1 and 8 every 21 days) followed by CCRT (radiation therapy 69.96 Gy with weekly cisplatin 40 mg/m{sup 2}), or CCRT alone. The accrual of 172 was planned to detect a 15% difference in 5-year overall survival (OS) with a 5% significance level and 80% power. Results: Between September 2004 and August 2012, 180 patients were accrued, and 172 (GCP 86, control 86) were analyzed by intention to treat. There was no significant difference in OS (3-year OS 94.3% [GCP] vs 92.3% [control]; hazard ratio 1.05; 1-sided P=.494]), disease-free survival (hazard ratio 0.77, 95% confidence interval 0.44-1.35, P=.362), and distant metastases–free survival (hazard ratio 0.80, 95% confidence interval 0.38-1.67, P=.547) between the 2 arms. Treatment compliance in the induction phase was good, but the relative dose intensity for concurrent cisplatin was significantly lower in the GCP arm. Overall, the GCP arm had higher rates of grades 3 and 4 leukopenia (52% vs 37%) and neutropenia (24% vs 12%), but grade 3 and 4 acute radiation toxicities were not statistically different between the 2 arms. The global quality of life scores were comparable in both arms. Conclusion: Induction chemotherapy with GCP before concurrent chemo-irradiation did not improve survival in locally advanced NPC.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Long-Term Outcomes Among Patients Who Achieve Complete or Near-Complete Responses After the Induction Phase of Bladder-Preserving Combined-Modality Therapy for Muscle-Invasive Bladder Cancer: A Pooled Analysis of NRG Oncology/RTOG 9906 and 0233

Purpose: To investigate the differences in outcomes among patients with muscle-invasive bladder cancer on NRG Oncology Radiation Therapy Oncology Group protocols 9906 and 0233 who achieved complete response and near-complete response after induction chemoradiation and then completed bladder-preserving therapy with chemoradiation therapy (chemo-RT) to full dose (60-64 Gy). Patients and Methods: A pooled analysis was performed on 119 eligible patients with muscle-invasive bladder cancer enrolled on NRG Oncology Radiation Therapy Oncology Group trials 9906 and 0233, who were classified as having a complete (T0) or near-complete (Ta or Tis) response after induction chemo-RT and completed consolidation with a total RT dose of at least 60 Gy. Bladder recurrence, salvage cystectomy rates, and disease-specific survival were estimated by the cumulative incidence method and bladder-intact and overall survivals by the Kaplan-Meier method. Results: Among the 119 eligible patients, 101 (85%) achieved T0, and 18 (15%) achieved Ta or Tis after induction chemo-RT and proceeded to consolidation. After a median follow-up of 5.9 years, 36 of 101 T0 patients (36%) versus 5 of 18 Ta or Tis patients (28%) experienced bladder recurrence (P=.52). Thirteen patients among complete responders eventually required late salvage cystectomy for tumor recurrence, compared with 1 patient among near-complete responders (P=.63). Disease-specific, bladder-intact, and overall survivals were not significantly different between T0 and Ta/Tis cases. Conclusions: The bladder recurrence and salvage cystectomy rates of the complete and the near-complete responders were similar. Therefore it is reasonable to recommend that patients with Ta or Tis after induction chemo-RT continue with bladder-sparing therapy with consolidation chemo-RT to full dose (60-64 Gy).

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Resveratrol attenuates methylglyoxal-induced mitochondrial dysfunction and apoptosis by Sestrin2 induction

Methylglyoxal is found in high levels in the blood and other tissues of diabetic patients and exerts deleterious effects on cells and tissues. Previously, we reported that resveratrol, a polyphenol in grapes, induced the expression of Sestrin2 (SESN2), a novel antioxidant protein, and inhibited hepatic lipogenesis. This study investigated whether resveratrol protects cells from the methylglyoxal-induced toxicity via SESN2 induction. Methylglyoxal significantly induced cell death in HepG2 cells. However, cells pretreated with resveratrol were rescued from methylglyoxal-induced apoptosis. Resveratrol attenuated glutathione (GSH) depletion and ROS production promoted by methylglyoxal. Moreover, mitochondrial damage was observed by methylglyoxal treatment, but resveratrol restored mitochondrial function, as evidenced by the observed lack of mitochondrial permeability transition and increased ADP/ATP ratio. Resveratrol treatment inhibited SESN2 depletion elicited by methylglyoxal. SESN2 overexpression repressed methylglyoxal-induced mitochondrial dysfunction and apoptosis. Likewise, rotenone-induced cytotoxicity was not observed in SESN2 overexpressed cells. Furthermore, siRNA knockdown of SESN2 reduced the ability of resveratrol to prevent methylglyoxal-induced mitochondrial permeability transition. In addition, when mice were exposed to methylglyoxal after infection of Ad-SESN2, the plasma levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) and GSH depletion by methylglyoxal in liver was reduced in Ad-SESN2 infected mice. Our results demonstrated that resveratrol is capable of protecting cells from methylglyoxal-induced mitochondrial dysfunction and oxidative stress via SESN2 induction. - Highlights: • Resveratrol decreased methylglyoxal-induced apoptosis. • Resveratrol attenuated GSH depletion and ROS production promoted by methylglyoxal. • Resveratrol restored the mitochondrial function by Sestrin2 induction. • Induction of Sestrin2 prevented methylglyoxal-induced GSH depletion in liver.

60 APPLIED LIFE SCIENCES↗

Measured Indoor Nitrogen Oxides in Homes with a Child with Asthma and Gas or Induction Electric Cooking

The Cooking Energy and Ventilation Impacts on Children's Asthma (CEVICA) study is a randomized control trial investigating the effects of replacing gas with induction electric ranges in the homes of children with asthma in California's San Joaquin Valley. Indoor air quality parameters and respiratory health indicators were measured over 2-week intensive at Baseline and after consecutive 3-month study phases, with half getting electric cooking at the start of Phase 1 and others in Phase 2. Indoor air measurements included time-integrated NO 2 and NO X by passive sampler and time-resolved NO 2 by electrochemical sensors. In the first 40 homes, data were collected during 61 intensives for gas cooking and 55 for induction. Cooking was identified using temperature sensors above the cooktop. Pollutant events were identified from sharp rises in concentrations Time integrated NOX species were lower with electric cooking, with mean differences of 14.2 ppb for NO 2 (95% CI: 9.6, 18.7; p < 0.001), 55.6 ppb for NO X (95% CI: 30.4, 80.9; p < 0.001), and 41.5 ppb for derived NO (95% CI: 19.7, 63.2; p < 0.001). A paired, within home analysis showed larger reductions in Group 2 (gas to induction) than Group 1 that remained electric across Phase 1 and Phase 2 for NO 2 (mean difference in As of 10.5 ppb; 95% CI: 5.6, 15.4; p < 0.001), NO X (32.3 ppb; 95% CI: 10.0, 54.5; p=0.007), and derived NO (21.8 ppb; 95% CI: 3.6, 40.0; p=0.022). Compared to electric cooking, gas had much higher rates of associated NO 2 events, and larger above-baseline NO 2 peaks. These preliminary results are consistent with prior findings that shifting to induction cooking can substantially lower indoor NO 2 compared with gas cooking.

Fang, Yi↗

Optical characteristics for capacitively and inductively radio frequency discharge and post-discharge of helium

The optical properties for radiofrequency (RF) post-discharge of pure helium (He) with two different methods as capacitively and inductively have been presented using the modified Boltzmann method in comparison. Optical emission spectroscopy (OES) is often used in the diagnosis of laboratory plasma, such as gas discharge plasma. OES is a very useful method for calculating of the electron temperature in the plasma and the determination of different atoms and molecules. In this study, OES is applied for characterizations of capacitively and inductively RF He plasma at pressures between 0.62 and 2.2 mbar for newly reactor type. Plasmas are generated with an RF power generator at a frequency of 13.56 MHz and output powers of 100, 160, and 200 W. Spectra have been evaluated in the range 200–1200 nm by an optical spectrometer. At low pressure, the main spectral features reported are the wavelengths of the atomic He transitions at 388.87 and 728.13 nm. The atomic emission intensities showed a maximum in inductive system when the pressure is about 0.62 mbar. OES of capacitive discharge and inductive discharge is compared in detail. The transition for 587.56 nm is shown to be increased in time.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗

Optimization of an in Vitro CYP450 Induction Assay Using Cryopreserved Cell Lines

Cytochrome P450 (CYP450) enzymes are responsible for the majority for Phase I metabolism. Induction occurs when a drug increases the rate of CYP450 enzyme production. As a result, the rates of metabolism of subsequent drugs increase, posing concerns for dosing and safety. To further expand the USAMRICD Absorption, Distribution, Metabolism, Excretion, and Toxicity Center of Excellence (ADMET CoE) profiling capabilities, a CYP450 induction assay is being developed using alternative cell lines to primary human hepatocytes to measure changes in gene expression of CYP1A2 and CYP3A4 isoenzymes. Primary human hepatocytes are the gold standard for evaluating P450 induction in vitro ; however, they have inherent limitations such as high costs, fastidious nature, and significant lot‐to‐lot variability. Induction assessments using cryopreserved hepatocytes and two immortalized cell lines, HepaRG and HepatoCells, are being conducted to determine a more robust, cost‐effective alternative model. Each cell line was exposed to the standard inducers rifampicin and omeprazole to assess CYP3A4 and CYP1A2 activity, respectively. Following a 72‐hour incubation period, RNA from the cell cultures was extracted and purified. Fold changes of gene expression were measured using real‐time quantitative PCR (RT‐qPCR). Hepatocytes displayed an average fold change of 92.7 for CYP3A4 and 49.6 for CYP1A2, whereas HepaRG displayed changes of 28.6 and 179.5, respectively. Average values for CYP3A4 and CYP1A2 for HepatoCells were 58.7 and 43.9. Based on the data, HepatoCells most closely mimicked cryopreserved hepatocytes in comparison to HepaRG cells. Additional data on assay parameters and technique optimization will be presented. Support or Funding Information Opinion disclaimer: The views expressed in this abstract are those of the authors and do not reflect the official policy of the Department of the Army, Department of Defense, or the U.S. Government. This project was generously supported in part by an appointment to the Postgraduate Research Participation Program at the U.S. Army Medical Research Institute of Chemical Defense administered by the Oak Ridge Institute for Science and Education through an interagency agreement between the U.S. Department of Energy and U.S. Army Medical Research and Materiel Command. Support is also provided by the Defense Threat Reduction Agency – Joint Science and Technology Office, Medical S&T Division. This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal .

Lim, Tae Young↗

Emergent Inductance from Chiral Orbital Currents in a Bulk Ferrimagnet

Here, we report the discovery of a new form of inductance in the bulk ferrimagnet Mn 3 ⁢Si 2 ⁢Te 6 , which features strong spin-orbit coupling, large magnetic anisotropy, and pronounced magnetoelastic interactions. Below its Curie temperature (𝑇 𝐶 ≈ 78 K), Mn 3 ⁢Si 2 ⁢Te 6 hosts chiral orbital currents (COC) that circulate within the crystal lattice and give rise to collective electronic behavior [Control of chiral orbital currents in a colossal magnetoresistance material, Nature (London) 611, 467 (2022).]. By applying a magnetic field along the hard 𝑐 axis and driving the system with low-frequency currents, we uncover a giant inductive response up to millhenry scale, originating from first-order reconfigurations of COC domains. These domains act as coherent mesoscopic inductive elements that resist reversal upon current reduction, producing a large electromotive force and sharply increasing voltage. This emergent inductance defies classical models, occurs without superconductivity or engineered nanostructures, and opens a new frontier in orbital-based quantum functionality and device concepts.

complex materials↗

Design of a low parasitic inductance SiC power module with double-sided cooling

In this paper, a low-parasitic inductance SiC power module with double-sided cooling is designed and compared with a baseline double-sided cooled module. With the unique 3D layout utilizing vertical interconnection, the power loop inductance is effectively reduced without sacrificing the thermal performance. Both simulations and experiments are carried out to validate the design. Q3D simulation results show a power loop inductance of 1.63 nH, verified by the experiment, indicating more than 60% reduction of power loop inductance compared with the baseline module. With 0Ω external gate resistance turn-off at 600V, the voltage overshoot is less than 9% of the bus voltage at a load of 44.6A.

Yang, Fei↗

Impact of the Transformer Magnetizing Inductance on the Performance of the Dual-Active Bridge Converter

The magnetizing inductance of the high-frequency transformer in the dual-active bridge (DAB) converter is usually assumed to be much larger than its leakage inductance, thereby the magnetizing current can be negligible. However, ignoring the magnetizing current will lead to an error in the DAB converter design process. This paper analyzes the operation and performance of the DAB converter for a general case in which the transformer magnetizing inductance is taken into consideration. The analysis shows that the magnetizing inductance impacts the soft-switching region, the power transfer capability, and the leakage inductor current. A simulation case study is provided to verify the analysis. A DAB converter prototype is built to experimentally validate the analysis as well.

Yin, Shiyuan↗

Stacked-Die SiC Half-Bridge Module with Minimum Loop Inductance

Minimizing parasitic inductance of power modules is needed to advance their electrical performance. Innovation in the past decade has driven down the inductance of SiC half-bridge power modules to around 1–2 nH by using multilayer, embedded, and hybrid structures. Further reduction becomes difficult, mainly limited by the excessive interconnects required for the planar placement of vertical conducting chips. To address this, a vertically stacked-die approach is proposed in this paper, taking advantage of the vertical conducting nature of the SiC chips. With ceramic decoupling capacitors integrated, 0.48 nH overall loop inductance is achieved and validated by experimental measurement. This paper also discusses potential approaches to further reduce the inductance.

Ribeiro, Pedro↗