DC-Link Voltage Balance Control in Three-phase Four-wire Active Power Filters

Wang, Yu,Guan, Yuanpeng,Xie, Yunxiang,Liu, Xiang The Korean Institute of Power Electronics 2016 JOURNAL OF POWER ELECTRONICS Vol.16 No.5

The three-phase four-wire shunt active power filter (APF) is an effective method to solve the harmonic problem in three-phase four-wire power systems. In addition, it has two possible topologies, a four-leg inverter and a three-leg inverter with a split-capacitor. There are some studies investigating DC-link voltage control in three-phase four-wire APFs. However, when compared to the four-leg inverter topology, maintaining the balance between the DC-link upper and lower capacitor voltages becomes a unique problem in the three-leg inverter with a split-capacitor topology, and previous studies seldom pay attention to this fact. In this paper, the influence of the balance between the two DC-link voltages on the compensation performance, and the influence of the voltage balance controller on the compensation performance, are analyzed. To achieve the balance between the two DC-link capacitor voltages, and to avoid the adverse effect the voltage balance controller has on the APF compensation performance, a new DC-link voltage balance control strategy for the three-phase four-wire split-capacitor APF is proposed. Representative simulation and experimental results are presented to verify the analysis and the proposed DC-link voltage balance control strategy.

Effective leaching and extraction of valuable metals from electrode material of spent lithium-ion batteries using mixed organic acids leachant

Yuanpeng Fu,Yaqun He,Hangchao Chen,Cuiling Ye,Qichang Lu,Rongnian Li,Weining Xie,Jie Wang 한국공업화학회 2019 Journal of Industrial and Engineering Chemistry Vol.79 No.-

The present work focuses on simultaneous recycling of Li and Co from crushed products of mixedelectrode materials using mixed organic acids, in which benzenesulfonic acid and formic acid werecooperatively used as the leaching reagents. Results show that the optimal leaching efficiency of 97% Coand 99% Li were obtained under the conditions of 1.3 mol/L benzenesulfonic acid, 1.5 mol/L formic acid, asolid to liquid (S/L) ratio of 30 g/L, and 40 min reaction time at 50 C. Meanwhile, the leaching of Li and Cofits well to logarithmic rate model with apparent activation energy of 32.7 and 47.0 kJ/mol in this givenleaching system, respectively. Besides, cobalt was directly recovered from the leach liquor as pure cobaltbenzene sulfonic with the recovery efficiency of 99%, and lithium can be entirely precipitated by addingphosphoric acid. Further, the reaction mechanism involves the leaching-hydrating-complexing model ofLiCoO2 particles was proposed based on the dissolution behavior of metals and then verified bymorphological and phase characterization (i.e. FT-IR, XRD and SEM-EDS) of the recycling product. Thewhole process is found to be effective and sustainable for recovery of Li, Co and graphite from mixedindustrial crushing product of spent LIBs.

Weather Forecasting Using Ensemble of Spatial-Temporal Attention Network and Multi-Layer Perceptron

Yuanpeng Li,Junwei Lang,Lei Ji,Jiqin Zhong,Zaiwen Wang,Yang Guo,Sailing He 한국기상학회 2021 Asia-Pacific Journal of Atmospheric Sciences Vol.57 No.3

Weather forecasting is a challenging task, which is especially suited for artificial intelligence due to the large amount of data involved. This paper proposed an end-to-end hybrid regression model, called Ensemble of Spatial-Temporal Attention Network and Multi-Layer Perceptron (E-STAN-MLP), to forecast surface temperature, humidity, wind speed, and wind direction at 24 automatic weather stations in Beijing. Combining the data from historical observations with the data from the numerical weather prediction (NWP) system, our proposed model give better results than the NWP system or previously reported algorithms. Our E-STAN-MLP model consists of two parts. One is to use the spatial-temporal attention based recurrent neural network to model the time series of meteorological elements. The other is a simple but efficient multilayer perceptron architecture forecasts the regression value while ignoring time dependence. Results at each time stamp are integrated together using a step-wise fusion strategy. Moreover, we use a joint loss step integrating both the regression loss function and the classification loss function to simultaneously forecast the wind speed and direction. Experiments demonstrate that our proposed E-STAN-MLP model achieves state-of-the-art results in weather forecasting.

DC-Link Voltage Balance Control in Three-phase Four-wire Active Power Filters

Yu Wang,Yuanpeng Guan,Yunxiang Xie,Xiang Liu 전력전자학회 2016 JOURNAL OF POWER ELECTRONICS Vol.16 No.5

The three-phase four-wire shunt active power filter (APF) is an effective method to solve the harmonic problem in three-phase four-wire power systems. In addition, it has two possible topologies, a four-leg inverter and a three-leg inverter with a split-capacitor. There are some studies investigating DC-link voltage control in three-phase four-wire APFs. However, when compared to the four-leg inverter topology, maintaining the balance between the DC-link upper and lower capacitor voltages becomes a unique problem in the three-leg inverter with a split-capacitor topology, and previous studies seldom pay attention to this fact. In this paper, the influence of the balance between the two DC-link voltages on the compensation performance, and the influence of the voltage balance controller on the compensation performance, are analyzed. To achieve the balance between the two DC-link capacitor voltages, and to avoid the adverse effect the voltage balance controller has on the APF compensation performance, a new DC-link voltage balance control strategy for the three-phase four-wire split-capacitor APF is proposed. Representative simulation and experimental results are presented to verify the analysis and the proposed DC-link voltage balance control strategy.

The Production of Bioflocculants by Bacillus licheniformis Using Molasses and Its Application in the Sugarcane Industry

Xiaoling Zhuang,Yuanpeng Wang,Qingbiao Li,Shan Yan,Ning He 한국생물공학회 2012 Biotechnology and Bioprocess Engineering Vol.17 No.5

A bioflocculant produced by B. licheniformis was investigated with regard to a low-cost culture medium and its industrial application. Molasses replaced sucrose as the sole carbon source in bioflocculant fermentation. The optimum low-cost culture medium was determined to be composed of 20 g/L molasses, 0.4 g/L urea, 0.4 g/L NaCl,0.2 g/L KH2PO4, 1.6 g/L K2HPO4, and 0.2 g/L MgSO4. The bioflocculant from B. licheniformis was then applied to treat sugarcane-neutralizing juice to remove colloids,suspended particles, and coloring matters in a sugar refinery factory. The optimal operation conditions were a bioflocculant dosage of 21 U/mL, pH 7.3 and a heating temperature of 100oC. The color and turbidity of the sugarcane juice reached IU 1267 and IU 206, respectively,after clarification with the bioflocculant; these values were almost the same as those acquired following treatment with polyacrylamide (PAM), the most widely applied flocculant in sugar industries. These results suggest the great potential for use of bioflocculants in the sugar refinery process. A bioflocculant produced by B. licheniformis was investigated with regard to a low-cost culture medium and its industrial application. Molasses replaced sucrose as the sole carbon source in bioflocculant fermentation. The optimum low-cost culture medium was determined to be composed of 20 g/L molasses, 0.4 g/L urea, 0.4 g/L NaCl,0.2 g/L KH2PO4, 1.6 g/L K2HPO4, and 0.2 g/L MgSO4. The bioflocculant from B. licheniformis was then applied to treat sugarcane-neutralizing juice to remove colloids,suspended particles, and coloring matters in a sugar refinery factory. The optimal operation conditions were a bioflocculant dosage of 21 U/mL, pH 7.3 and a heating temperature of 100oC. The color and turbidity of the sugarcane juice reached IU 1267 and IU 206, respectively,after clarification with the bioflocculant; these values were almost the same as those acquired following treatment with polyacrylamide (PAM), the most widely applied flocculant in sugar industries. These results suggest the great potential for use of bioflocculants in the sugar refinery process.

Nanomagnetic Sensing System and Biomarker Quantification for PERSONAL Medicine

Jian-Ping Wang,Yuanpeng Li,Ying Jing,Balasubramanian Srinivasan,Xiaofeng Yao,Marie A. Hugger,Chengguo Xing 한국자기학회 2010 한국자기학회 학술연구발표회 논문개요집 Vol.2010 No.12

A Modified PiggyBac Transposon System Mediated by Exogenous mRNA to Perform Gene Delivery in Bovine Mammary Epithelial Cells

Guangdong Hu,Jing Wang,Hui Huang,Fusheng Quan,Jian Kang,Yongyan Wu,Yuanpeng Gao,Feng Su,Minghao Shao,Yong Zhang 한국생물공학회 2014 Biotechnology and Bioprocess Engineering Vol.19 No.2

Transposons are widely used for geneticengineering in various model organisms. Recently, piggyBac(PB) has been developed as a transposable and efficientgene transfer tool in mammalian cells. In the present study,we developed three types of PB transposon systemscontaining a dual plasmid system (DPS), a single plasmidsystem (SPS), and a DNA-mRNA combined system (DRPS)and characterized their basic properties in HEK293 cells. The basic elements of the donor plasmid included aselectable-reporter gene expression cassette, two loxP sitesin the same orientation, a multiple cloning site, and twochicken β-globin insulator core elements. We further identifiedthe function of the selectable-reporter and examined PBintegration sites in the human genome. Moreover, wecompared the transposition efficacy and found that SPStransposed more efficiently, as compared to DPS; integrationinto the host genome was determined by measuring PBaseactivity. Results discovered the loss of PBase activity in theDRPS, indicating that this system is much more biologicallysafe, as compared to DPS and SPS. Finally, we employedthe DRPS to successfully perform a gene delivery intobovine mammary epithelial cells (BMECs). Taken together,the information from this study will improve the flexibilityof PB transposon systems and reduce the genotoxicity ofPBase in genetic engineering.

Genome-wide association analysis for yield-related traits at the R6 stage in a Chinese soybean mini core collection

Li Xiangnan,Zhou Yang,Bu Yuanpeng,Wang Xinfang,Zhang Yumei,Guo Na,Zhao Jinming,Xing Han 한국유전학회 2021 Genes & Genomics Vol.43 No.8

Background Soybean (Glycine max (L.) Merr.) is an economically important crop for vegetable oil and protein production, and yield is a critical trait for grain/vegetable uses of soybean. However, our knowledge of the genes controlling the vegetable soybean yield remains limited. Objective To better understand the genetic basis of the vegetable soybean yield. Methods The 100-pod fresh weight (PFW), 100-seed fresh weight (SFW), kernel percent (KP) and moisture content of fresh seeds (MCFS) at the R6 stage are four yield-related traits for vegetable soybean. We investigated a soybean mini core collection composed of 224 germplasm accessions for four yield-related traits in two consecutive years. Based on 1514 single nucleotide polymorphisms (SNPs), genome-wide association studies (GWAS) were conducted using a mixed linear model (MLM). Results Extensive phenotypic variation existed in the soybean mini core collection and signifcant positive correlations were shown among most of traits. A total of 16 SNP markers for PFW, SFW, KP and MCFS were detected in all environments via GWAS. Nine SNP markers were repeatedly identifed in two environments. Among these markers, eight were located in or near regions where yield-related QTLs have been reported in previous studies, and one was a novel genetic locus identifed in this study. In addition, we conducted candidate gene analysis to the large-efect SNP markers, a total of twelve genes were proposed as potential candidate genes of soybean yield at the R6 stage. Conclusion These results will be benefcial for understanding the genetic basis of soybean yield at the R6 stage and facilitating the pyramiding of favourable alleles for future high-yield breeding by marker-assisted selection in vegetable soybean.

Preparation of γ-alumina nanoparticle modified polyacrylamide composite and study on its solid phase extraction of Sunset Yellow

Wanjun Li,Qiong Jia,Zhenyu Zhang,Yuanpeng Wang 한국화학공학회 2016 Korean Journal of Chemical Engineering Vol.33 No.4

An organic-inorganic composite, γ-alumina nanoparticle modified polyacrylamide, was synthesized in this study. The composite was characterized by scanning electron microscope, nitrogen adsorption-desorption measurement, thermal gravimetric analyzer, differential scanning calorimetry, and Fourier-transformed infrared spectrometer. A novel solid-phase extraction method with the synthesized composite as the adsorbent was developed for the enrichment of Sunset Yellow coupled with ultraviolet-visible spectrophotometry. To obtain the optimum extraction efficiency, the experimental parameters in the processes of preparation of the adsorbent and solid-phase extraction were studied including synthesis temperature, synthesis time, the dosage of γ-alumina nanoparticles, sample flow rate, sample pH, eluant concentration, and eluant flow rate. Under the optimum conditions, the detection limit of the developed method was calculated to be 0.037 μg mL−1 with intra-day and inter-day relative standard deviation values of 2.57% and 3.89%, respectively. When the method was applied to the determination of Sunset Yellow in beverages, satisfactory recoveries were obtained in the range of 92.3-109.8%.