A switched reluctance motor torque ripple reduction strategy with deadbeat current control

This paper presents a switched reluctance motor (SRM) torque ripple reduction strategy with deadbeat current control. In this method, the SRM torque is indirectly controlled by the phase current. The deadbeat control method can predict the duty cycle of the switching signal for the next control period according to current error, and achieve an accurate current tracking. Thus, SRM torque control error can be reduced significantly. The feasibility and effectiveness of the proposed strategy have been verified in both simulation and experimental studies

A switched reluctance motor torque ripple reduction strategy with deadbeat current control and active thermal management

This paper presents a switched reluctance motor (SRM) torque ripple reduction strategy with deadbeat current control and active thermal management. In this method, the SRM torque is indirectly controlled by the phase current. A deadbeat current control method is used to improve the SRM phase current control accuracy, so that SRM torque control error can be reduced significantly. According to the online measurement of the power switching device temperature, the switching frequency will be reduced to prevent the SRM power converter from being damaged by over-temperature. The feasibility and effectiveness of the proposed strategy have been verified in both simulation and experimental studies

Principle and topology derivation of single-inductor multi-input multi-output DC-DC converters

Single-inductor multi-input multi-output (SI-MIMO) dc-dc converters are attractive in the engineering applications due to the advantage of high power density and low cost. In order to explore as many as possible SI-MIMO topologies, this paper proposes a simple and effective topology derivation principle which only requires three steps. Firstly, three basic cells consisting of a single inductor and multiple sets of unidirectional switches as well as inputs/outputs are proposed. Secondly, integrate them with the inductor branch of the typical single-input single-output converters. Finally, implement the topology simplification by removing unnecessary switches/diodes. Based on the proposed principle, a large number of SI-MIMO topologies are derived from buck, boost, buck-boost and non-inverting buck-boost converters in the paper. With more topology choices having different performance characteristics, it is very beneficial for engineers to gain an optimized design that a preferred one can be selected out after comprehensive comparison. As an example, topology comparison and selection among a family of single-inductor single-input dual-output converters is also conducted in the paper. Besides, performance analysis, design considerations and simulation/experiment results of the selected optimum topology are demonstrated in detail to verify its advantages

In-situ Health Monitoring of IGBT Modules of an On-line Medium-voltage Inverter System Using Industrial Internet of Things

Requirements of the Internet of things for the network includes the ability to monitor the equipment and devices. Nowadays, the reliability of a power electronics converter has raised concerns of both academia and industry. In particular, power semiconductor devices are continuously exposed to excessive stress while being designed with high power handling capability and are considered as the most fragile component in power converters suffering from a high failure rate. Aiming to find an effective monitoring method which is also helpful for the Internet of Things and improve the reliability of a three-level neutral-point-clamped power inverter, an in-situ health monitoring method is proposed by harnessing the inverter operational characteristics and degradation sensitive electrical parameters to address the IGBT wire bonding faults. The zero voltage state provides an inherent redundant feature that allows for a power switch to be diagnosed during its normal operation in a neutral-point-clamped power inverter. The proposed prognostic approach obtains both the wire bonding failure features and junction temperature from the terminals of an IGBT module, which is regarded as non-invasive on-line health monitoring. The system performance can be affected by the designated testing point and testing window, which is discussed and experimentally validated. The proposed technique allows unhealthy wire bonding in IGBT modules online monitoring during the operational period of the inverter. And the proposed in-situ health monitoring of IGBT modules can be used for the industrial Internet of things

Efficacy and safety of sparsentan versus irbesartan in patients with IgA nephropathy (PROTECT): 2-year results from a randomised, active-controlled, phase 3 trial

Background Sparsentan, a novel, non-immunosuppressive, single-molecule, dual endothelin angiotensin receptor antagonist, significantly reduced proteinuria versus irbesartan, an angiotensin II receptor blocker, at 36 weeks (primary endpoint) in patients with immunoglobulin A nephropathy in the phase 3 PROTECT trial's previously reported interim analysis. Here, we report kidney function and outcomes over 110 weeks from the double-blind final analysis. Methods PROTECT, a double-blind, randomised, active-controlled, phase 3 study, was done across 134 clinical practice sites in 18 countries throughout the Americas, Asia, and Europe. Patients aged 18 years or older with biopsy-proven primary IgA nephropathy and proteinuria of at least 1·0 g per day despite maximised renin–angiotensin system inhibition for at least 12 weeks were randomly assigned (1:1) to receive sparsentan (target dose 400 mg oral sparsentan once daily) or irbesartan (target dose 300 mg oral irbesartan once daily) based on a permuted-block randomisation method. The primary endpoint was proteinuria change between treatment groups at 36 weeks. Secondary endpoints included rate of change (slope) of the estimated glomerular filtration rate (eGFR), changes in proteinuria, a composite of kidney failure (confirmed 40% eGFR reduction, end-stage kidney disease, or all-cause mortality), and safety and tolerability up to 110 weeks from randomisation. Secondary efficacy outcomes were assessed in the full analysis set and safety was assessed in the safety set, both of which were defined as all patients who were randomly assigned and received at least one dose of randomly assigned study drug. This trial is registered with ClinicalTrials.gov, NCT03762850. Findings Between Dec 20, 2018, and May 26, 2021, 203 patients were randomly assigned to the sparsentan group and 203 to the irbesartan group. One patient from each group did not receive the study drug and was excluded from the efficacy and safety analyses (282 [70%] of 404 included patients were male and 272 [67%] were White) . Patients in the sparsentan group had a slower rate of eGFR decline than those in the irbesartan group. eGFR chronic 2-year slope (weeks 6–110) was −2·7 mL/min per 1·73 m2 per year versus −3·8 mL/min per 1·73 m2 per year (difference 1·1 mL/min per 1·73 m2 per year, 95% CI 0·1 to 2·1; p=0·037); total 2-year slope (day 1–week 110) was −2·9 mL/min per 1·73 m2 per year versus −3·9 mL/min per 1·73 m2 per year (difference 1·0 mL/min per 1·73 m2 per year, 95% CI −0·03 to 1·94; p=0·058). The significant reduction in proteinuria at 36 weeks with sparsentan was maintained throughout the study period; at 110 weeks, proteinuria, as determined by the change from baseline in urine protein-to-creatinine ratio, was 40% lower in the sparsentan group than in the irbesartan group (−42·8%, 95% CI −49·8 to −35·0, with sparsentan versus −4·4%, −15·8 to 8·7, with irbesartan; geometric least-squares mean ratio 0·60, 95% CI 0·50 to 0·72). The composite kidney failure endpoint was reached by 18 (9%) of 202 patients in the sparsentan group versus 26 (13%) of 202 patients in the irbesartan group (relative risk 0·7, 95% CI 0·4 to 1·2). Treatment-emergent adverse events were well balanced between sparsentan and irbesartan, with no new safety signals. Interpretation Over 110 weeks, treatment with sparsentan versus maximally titrated irbesartan in patients with IgA nephropathy resulted in significant reductions in proteinuria and preservation of kidney function.</p