In this study, a probabilistic neural network (PNN) is used to estimate the state of health (SOH) of Li-ion batteries. The accurate prediction of SOH can help avoid inconveniences or fatal accidents ...from the sudden malfunction of the battery. A total of 110 pieces of Li-Co batteries are used. Constant current/voltage recharging and constant current discharging are performed for the life-cycle test of the battery. The data obtained from the recharging and discharging electric characteristics as well as the life-cycle test of the battery are used to estimate the SOH of the battery. The test data show that the constant current charging time, the instantaneous voltage drop at the start of discharging, and the open circuit voltage are the most important characteristics for estimating the SOH of the battery. The PNN is trained using 100 pieces of batteries. The remaining 10 pieces are used to verify the feasibility of the proposed method. The effectiveness of the PNN training using a number of samples is discussed and analyzed. The results show that the average error of the prediction is 0.28% and the standard deviation is 1.15%. The computation time of the PNN is 62.5 ms. Thus, the proposed method can accurately estimate the SOH of the battery in a short period.
In this paper, a high step-up dc-dc converter is presented. The proposed converter features a high voltage conversion ratio and high efficiency with a reasonable duty cycle by adopting an active ...switched inductor and a coupled inductor. The voltage stresses on the power switches are lower, and with the energy stored in the leakage inductor being recycled, its efficiency is improved. Moreover, current stresses of the power switches are greatly reduced as caused by inductors parallel charging and series discharging on the active switched inductor. Loss analyses of its components are also presented. A comparison including component counts, voltage gain and voltage stresses of power switches with other relevant converters are analyzed. Eventually, a laboratory prototype with an input voltage of 24 V-36 V and an output voltage of 400 V with 400 W rated power is implemented to validate the correctness and effectiveness of the theoretical analyses.
The grid-connected AC module is an alternative solution in photovoltaic (PV) generation systems. It combines a PV panel and a micro-inverter connected to grid. The use of a high step-up converter is ...essential for the grid-connected micro-inverter because the input voltage is about 15 V to 40 V for a single PV panel. The proposed converter employs a Zeta converter and a coupled inductor, without the extreme duty ratios and high turns ratios generally needed for the coupled inductor to achieve high step-up voltage conversion; the leakage-inductor energy of the coupled inductor is efficiently recycled to the load. These features improve the energy-conversion efficiency. The operating principles and steady-state analyses of continuous and boundary conduction modes, as well as the voltage and current stresses of the active components, are discussed in detail. A 25 V input voltage, 200 V output voltage, and 250 W output power prototype circuit of the proposed converter is implemented to verify the feasibility; the maximum efficiency is up to 97.3%, and full-load efficiency is 94.8%.
Prednisolone is involved in glucose homeostasis and has been used for treatment for aristolochic acid (AA) nephropathy (AAN), but its effect on glycolysis in kidney has not yet been clarified. This ...study aims to investigate the effect in terms of altered proteins after prednisolone treatment in a mice model of AAN using a proteomics technique. The six-week C3H/He female mice were administrated AA (0.5 mg/kg/day) for 56 days. AA+P group mice were then given prednisolone (2 mg/kg/day) via oral gavage for the next 14 days, and AA group mice were fed water instead. The tubulointerstitial damage was improved after prednisolone treatment comparing to that of AA group. Kidney homogenates were harvested to perform the proteomics analysis with fluorogenic derivatization-liquid chromatography-tandem mass spectrometry method (FD-LC-MS/MS). On the other hand, urinary methylglyoxal and D-lactate levels were determined by high performance liquid chromatography with fluorescence detection. There were 47 altered peaks and 39 corresponding proteins on day 14 among the groups, and the glycolysis-related proteins, especially glyoxalase 1 (GLO1), fructose-bisphosphate aldolase B (aldolase B), and triosephosphate isomerase (TPI), decreased in the AA+P group. Meanwhile, prednisolone decreased the urinary amount of methylglyoxal (AA+P: 2.004 ± 0.301 μg vs. AA: 2.741 ± 0.630 μg, p < 0.05), which was accompanied with decrease in urinary amount of D-lactate (AA+P: 54.07 ± 5.45 μmol vs. AA: 86.09 ± 8.44 μmol, p < 0.05). Prednisolone thus alleviated inflammation and interstitial renal fibrosis. The renal protective mechanism might be associated with down-regulation of GLO1 via reducing the contents of methylglyoxal derived from glycolysis. With the aid of proteomics analysis and the determination of methylglyoxal and its metabolite-D-lactate, we have demonstrated for the first time the biochemical efficacy of prednisolone, and urinary methylglyoxal and its metabolite-D-lactate might be potential biomarkers for AAN.
In this paper, a novel multilevel dc-ac inverter is proposed. The proposed multilevel inverter generates seven-level ac output voltage with the appropriate gate signals' design. Also, the low-pass ...filter is used to reduce the total harmonic distortion of the sinusoidal output voltage. The switching losses and the voltage stress of power devices can be reduced in the proposed multilevel inverter. The operating principles of the proposed inverter and the voltage balancing method of input capacitors are discussed. Finally, a laboratory prototype multilevel inverter with 400-V input voltage and output 220 V rms /2 is implemented. The multilevel inverter is controlled with sinusoidal pulse-width modulation (SPWM) by TMS320LF2407 digital signal processor (DSP). Experimental results show that the maximum efficiency is 96.9% and the full load efficiency is 94.6%.
This paper proposes a novel balancing method for series-connected batteries applications. The proposed method uses a transformer to couple the energy from charger or discharger to batteries for ...energy balancing. The proposed method has the advantages of high efficiency, compact size, suitable for any type of switching converter, load-related balancing energy, and extremely simple structure without any active switch for voltage balance function. Three converters, including a CLL converter, an interleaved noninverting buck-boost (BB) converter, and a noninverting BB converter, with voltage balancing function and state-of-charge balancing function are built to verify the feasibility of the proposed balancing methods.
A novel two-switch high-step-up isolated converter with voltage lift is proposed in this paper. The proposed isolated converter utilizes a transformer with low turn ratio to achieve high step-up ...gain. The secondary winding charges two boosting capacitors in parallel as switches during the switch-on period, and two boosting capacitors are discharged in series during the switch-off period. Thus, the converter has high voltage gain with appropriate duty ratio. In addition, by using two clamping diodes and a capacitor on the primary side, leakage energy is recycled, and the voltage spikes of the two active switches are clamped, thereby improving conversion efficiency. Finally, experimental results based on a prototype implemented in the laboratory with an input voltage of 24 V, an output voltage of 200 V, and an output power of 200 W verify the performance of the proposed isolated converter; full-load efficiency is nearly 93%.
An ultra-large voltage conversion ratio converter is proposed by integrating a switched-capacitor circuit with a coupled inductor technology. The proposed converter can be seen as an equivalent ...parallel connection to the load of a basic boost converter and a number of forward converters, each one containing a switched-capacitor circuit. All the stages are activated by the boost switch. A single active switch is required, with no need of extreme duty-ratio values. The leakage energy of the coupled inductor is recycled to the load. The inrush current problem of switched capacitors is restrained by the leakage inductance of the coupled-inductor. The above features are the reason for the high efficiency performance. The operating principles and steady state analyses of continuous, discontinuous and boundary conduction modes are discussed in detail. To verify the performance of the proposed converter, a 200 W/20 V to 400 V prototype was implemented. The maximum measured efficiency is 96.4%. The full load efficiency is 95.1%.
This paper proposes a high step‐up DC–DC converter which integrates switched‐inductor and switched‐capacitor techniques with a four‐winding coupled‐inductor. With switched‐inductor technique, two ...primary windings of the coupled‐inductor are charged in parallel and discharged in series to obtain high voltage gain. Moreover, by adding two sets of diode‐capacitor circuits on both primary side windings, not only can recycle the energy causing the voltage spike on the power switches, but can also lift the conversion ratio. Then, the power switches with lower voltage stress are used to improve the efficiency of the proposed converter. The operating principle, steady state analyses, and key parameters design of the proposed converter are discussed and provided. Finally, a 400 W laboratory prototype with 24 V input voltage and 480 V output voltage is constructed and tested to validate the performance. The highest and full load efficiencies are 95.8% and 94.8%, respectively.
This paper proposes a high step‐up DC–DC converter which integrates switched‐inductor and switched‐capacitor techniques with a four‐winding coupled‐inductor. With switched‐inductor technique, the primary windings of the coupled‐inductor are charged in parallel and discharged in series to obtain high voltage gain. By adding switched‐capacitor technique, the output voltage gain can be further improved.
The relationship between methylglyoxal (MGO) and D-lactate during saikosaponin C (SSC) treatment of mice with accelerated nephrotoxic serum (NTS) nephritis was investigated. NTS nephritis was induced ...by administration of anti-basement membrane antibodies to C57BL/6 mice and three dosages of SSC were administered for 14 days. Proteinuria, blood urea nitrogen, serum creatinine, renal histology, urinary MGO and d-lactate changes were examined. Compared to the NTS control group, the middle dosage (10 mg/kg/day) of SSC significantly alleviated the development of nephritis based on urine protein measurements (34.40 ± 6.85 vs. 17.33 ± 4.79 mg/day, p<0.05). Pathological observation of the glomerular basement membrane (GBM) revealed monocyte infiltration, hypertrophy, and crescents were alleviated, and injury scoring also showed improved efficacy for the middle dose of SSC during nephritis (7.92 ± 1.37 vs. 3.50 ± 1.14, p<0.05). Moreover, the significant decreases in urinary levels of MGO (24.71 ± 3.46 vs. 16.72 ± 2.36 μg/mg, p<0.05) and D-lactate (0.31 ± 0.04 vs. 0.23 ± 0.02 μmol/mg, p<0.05) were consistent with the biochemical and pathological examinations. This study demonstrates that MGO and D-lactate may reflect the extent of damage and the efficacy of SSC in NTS nephritis; further studies are required to enable clinical application.
PDF
