Auxiliary Resonant Commutated Pole Inverter (ARCPI) with SiC MOSFETs for efficient Vehicle-to-Grid (V2G) charging

The need for energy storages is growing with an increasing share of renewable energy sources in the electricity grid. The roll-out of electric vehicles into the mass market will bring huge battery storage capacities into the grid, which have remained largely unused so far but could be used to temporarily store energy. One key enabler for this is low-cost, efficient and compact power electronics, like the Auxiliary Resonant Commutated Pole Inverter (ARCPI), which is a promising topology for bidirectional AC/DC converters in battery chargers. In this paper, we present the principle of operation and a simulation of the ARCPI. In addition, we provide first results from an ARCPI prototype using SiC MOSFETs designed for a power of up 22 kW, DC link voltages of up to 920 V and peak efficiencies beyond 99 %

Battery cycler to generate open li-ion cell aging data and models

Battery degradation is relevant for the lifetime, cost, and life cycle analysis of electric vehicles and stationary storage. Publicly available, reusable battery aging data is scarce and aging experiments are time-consuming and expensive. This poster gives a brief overview of existing battery aging data and models. We then present our battery cycler hardware, which we intend to use to generate open battery degradation data and models. After analyzing the switching behavior, efficiency, and control behavior of the hardware, we give an insight into the generated data and the user interface of the battery cycler. Finally, we provide an outlook on the further development of the project

Dimensioning Microgrids for Productive Use of Energy in the Global South—Considering Demand Side Flexibility to Reduce the Cost of Energy

Microgrids using renewable energy sources play an important role in providing universal electricity access in rural areas in the Global South. Current methods of system dimensioning rely on stochastic load profile modeling, which has limitations in microgrids with industrial consumers due to high demand side uncertainties. In this paper, we propose an alternative approach considering demand side management during system design which we implemented using a genetic scheduling algorithm. The developed method is applied to a test case system on Idjwi Island, Democratic Republic of the Congo (DRC), which is to be powered by a micro hydropower plant (MHP) in combination with a photovoltaic (PV) system and a battery energy storage system (BESS). The results show that the increased flexibility of industrial consumers can significantly reduce the cost of electricity. Most importantly, the presented method quantifies the trade-off between electricity cost and consumer flexibility. This gives local stakeholders the ability to make an informed compromise and design an off-grid system that covers their electricity needs in the most cost-efficient way

Design and experimental verification of advanced control strategies to provide ancillary services with a bidirectional Vehicle-to-Grid (V2G) inverter

Vehicle-to-Grid (V2G) may contribute significantly to supporting renewable electricity grids in the future. In addition to flexibly feeding back energy into the grid, V2G inverters could also provide ancillary services to actively stabilize the grid. This poster presents different controller structures for providing ancillary system services with bidirectional AC/DC inverters, such as virtual inertia, frequency, and voltage control. After providing examples of the controllers, we verify them on our prototype and discuss the measurements. The results show that V2G inverters can indeed contribute to grid stabilization

Quantum size effect in Pb(100) films: the role of symmetry and implication for film growth

We show from density-functional calculations that Pb(100) thin films exhibit quantum size effect with a bilayer periodicity in film energies, film relaxations, and work functions, which originate from different symmetry of the stacking geometry of odd and even layer films. The bilayer periodicity of the film energy is argued to survive on a semiconductor substrate, which should allow the growth of ``magically'' thick even-layer Pb(100) films. Furthermore, it is found that the quantum well states in a simple metal film can be classified into $\sigma$-bonded and $\pi$-bonded states, which quantize independently

High-Resolution Real-World Electricity Data from Three Microgrids in the Global South

Microgrids are a promising solution for providing renewable electricity access to rural populations in the Global South. To ensure such renewable microgrids are affordable, careful planning and dimensioning are required. High-resolution data on electricity generation and consumption is necessary for optimal design. Unfortunately, real-world electricity data for microgrids in the Global South is scarce, and the little data that is available has a low temporal resolution. Therefore, in this paper, we introduce a unique highresolution real-world electricity data set from three microgrids in the Democratic Republic of the Congo, Rwanda, and Haiti. The data has a temporal resolution of up to five seconds and focuses on microgrids with renewable generation from either hydropower or photovoltaic systems. Furthermore, we include data from both residential and industrial microgrids. We describe the recorded data and highlight the advantages of the high resolution. We demonstrate how this resolution offers insight into consumption patterns and enables the analysis of grid voltage and frequency, which is highly relevant for the planning and dimensioning of affordable renewable microgrids in the Global South

High-resolution real-world electricity data from three microgrids in the global south

Microgrids are a promising solution for providing renewable electricity access to rural populations in the Global South. To ensure such renewable microgrids are affordable, careful planning and dimensioning are required. High-resolution data on electricity generation and consumption is necessary for optimal design. Unfortunately, real-world electricity data for microgrids in the Global South is scarce, and the limited data that is available has a low temporal resolution. Therefore, in this paper, we introduce a unique high-resolution real-world electricity data set from three micro-grids in the Democratic Republic of the Congo, Rwanda, and Haiti. The data has a temporal resolution of up to five seconds and focuses on microgrids with renewable generation from either hydropower or photovoltaic systems. Furthermore, we include data from both residential and industrial microgrids. We describe the recorded data and highlight the advantages of the high resolution. We demonstrate how this resolution offers insight into consumption patterns and enables the analysis of grid voltage and frequency, which is highly relevant for the planning and dimensioning of affordable renewable microgrids in the Global South

A rightward shift in the visuospatial attention vector with healthy aging

The study of lateralised visuospatial attention bias in non-clinical samples has revealed a systematic group-level leftward bias (pseudoneglect), possibly as a consequence of right hemisphere dominance for visuospatial attention. Pseudoneglect appears to be modulated by age, with a reduced or even reversed bias typically present in elderly participants. It has been suggested that this shift in bias may arise due to disproportionate aging of the right hemisphere and/or an increase in complementary functional recruitment of the left hemisphere for visuospatial processing. In this study, we report rightward shifts in subjective midpoint judgement relative to healthy young participants whilst elderly participants performed a computerized version of the landmark task (in which they had to judge whether a transection mark appeared closer to the right or left end of a line) on three different line lengths. This manipulation of stimulus properties led to a similar behavioural pattern in both the young and the elderly: a rightward shift in subjective midpoint with decreasing line length, which even resulted in a systematic rightward bias in elderly participants for the shortest line length (1.98° of visual angle). Overall performance precision for the task was lower in the elderly participants regardless of line length, suggesting reduced landmark task discrimination sensitivity with healthy aging. This rightward shift in the attentional vector with healthy aging is likely to result from a reduction in right hemisphere resources/dominance for attentional processing in elderly participants. The significant rightward bias in the elderly for short lines may even suggest a reversal of hemisphere dominance in favour of the left hemisphere/right visual field under specific conditions

Ruxolitinib for Glucocorticoid-Refractory Acute Graft-versus-Host Disease

BACKGROUND: Acute graft-versus-host disease (GVHD) remains a major limitation of allogeneic stem-cell transplantation; not all patients have a response to standard glucocorticoid treatment. In a phase 2 trial, ruxolitinib, a selective Janus kinase (JAK1 and JAK2) inhibitor, showed potential efficacy in patients with glucocorticoid-refractory acute GVHD. METHODS: We conducted a multicenter, randomized, open-label, phase 3 trial comparing the efficacy and safety of oral ruxolitinib (10 mg twice daily) with the investigator's choice of therapy from a list of nine commonly used options (control) in patients 12 years of age or older who had glucocorticoid-refractory acute GVHD after allogeneic stem-cell transplantation. The primary end point was overall response (complete response or partial response) at day 28. The key secondary end point was durable overall response at day 56. RESULTS: A total of 309 patients underwent randomization; 154 patients were assigned to the ruxolitinib group and 155 to the control group. Overall response at day 28 was higher in the ruxolitinib group than in the control group (62% [96 patients] vs. 39% [61]; odds ratio, 2.64; 95% confidence interval [CI], 1.65 to 4.22; P<0.001). Durable overall response at day 56 was higher in the ruxolitinib group than in the control group (40% [61 patients] vs. 22% [34]; odds ratio, 2.38; 95% CI, 1.43 to 3.94; P<0.001). The estimated cumulative incidence of loss of response at 6 months was 10% in the ruxolitinib group and 39% in the control group. The median failure-free survival was considerably longer with ruxolitinib than with control (5.0 months vs. 1.0 month; hazard ratio for relapse or progression of hematologic disease, non-relapse-related death, or addition of new systemic therapy for acute GVHD, 0.46; 95% CI, 0.35 to 0.60). The median overall survival was 11.1 months in the ruxolitinib group and 6.5 months in the control group (hazard ratio for death, 0.83; 95% CI, 0.60 to 1.15). The most common adverse events up to day 28 were thrombocytopenia (in 50 of 152 patients [33%] in the ruxolitinib group and 27 of 150 [18%] in the control group), anemia (in 46 [30%] and 42 [28%], respectively), and cytomegalovirus infection (in 39 [26%] and 31 [21%]). CONCLUSIONS: Ruxolitinib therapy led to significant improvements in efficacy outcomes, with a higher incidence of thrombocytopenia, the most frequent toxic effect, than that observed with control therapy