An Inductance Voltage Vector Control Strategy and Stability Study Based on Proportional Resonant Regulators under the Stationary αβ Frame for PWM Converters

Qiang Sun,Kexin Wei,Chenghai Gao,Shasha Wang,Bin Liang 전력전자학회 2016 JOURNAL OF POWER ELECTRONICS Vol.16 No.3

The mathematical model of a three phase PWM converter under the stationary αβ reference frame is deduced and constructed based on a Proportional-Resonant (PR) regulator, which can replace trigonometric function calculation, Park transformation, real-time detection of a Phase Locked Loop and feed-forward decoupling with the proposed accurate calculation of the inductance voltage vector. To avoid the parallel resonance of the LCL topology, the active damping method of the proportional capacitor-current feedback is employed. As to current vector error elimination, an optimized PR controller of the inner current loop is proposed with the zero-pole matching (ZPM) and cancellation method to configure the regulator. The impacts on system’s characteristics and stability margin caused by the PR controller and control parameter variations in the inner-current loop are analyzed, and the correlations among active damping feedback coefficient, sampling and transport delay, and system robustness have been established. An equivalent model of the inner current loop is studied via the pole-zero locus along with the pole placement method and frequency response characteristics. Then, the parameter values of the control system are chosen according to their decisive roles and performance indicators. Finally, simulation and experimental results obtained while adopting the proposed method illustrated its feasibility and effectiveness, and the inner current loop achieved zero static error tracking with a good dynamic response and steady-state performance.

An Inductance Voltage Vector Control Strategy and Stability Study Based on Proportional Resonant Regulators under the Stationary αβ Frame for PWM Converters

Sun, Qiang,Wei, Kexin,Gao, Chenghai,Wang, Shasha,Liang, Bin The Korean Institute of Power Electronics 2016 JOURNAL OF POWER ELECTRONICS Vol.16 No.3

The mathematical model of a three phase PWM converter under the stationary αβ reference frame is deduced and constructed based on a Proportional-Resonant (PR) regulator, which can replace trigonometric function calculation, Park transformation, real-time detection of a Phase Locked Loop and feed-forward decoupling with the proposed accurate calculation of the inductance voltage vector. To avoid the parallel resonance of the LCL topology, the active damping method of the proportional capacitor-current feedback is employed. As to current vector error elimination, an optimized PR controller of the inner current loop is proposed with the zero-pole matching (ZPM) and cancellation method to configure the regulator. The impacts on system's characteristics and stability margin caused by the PR controller and control parameter variations in the inner-current loop are analyzed, and the correlations among active damping feedback coefficient, sampling and transport delay, and system robustness have been established. An equivalent model of the inner current loop is studied via the pole-zero locus along with the pole placement method and frequency response characteristics. Then, the parameter values of the control system are chosen according to their decisive roles and performance indicators. Finally, simulation and experimental results obtained while adopting the proposed method illustrated its feasibility and effectiveness, and the inner current loop achieved zero static error tracking with a good dynamic response and steady-state performance.

Y-Single Nucleotide Polymorphisms Diversity in Chinese Indigenous Horse

Han, Haoyuan,Zhang, Qin,Gao, Kexin,Yue, Xiangpeng,Zhang, Tao,Dang, Ruihua,Lan, Xianyong,Chen, Hong,Lei, Chuzhao Asian Australasian Association of Animal Productio 2015 Animal Bioscience Vol.28 No.8

In contrast to high genetic diversity of mitochondrial DNA (mtDNA), equine Y chromosome shows extremely low variability, implying limited patrilines in the domesticated horse. In this study, we applied direct sequencing and restriction fragment length polymorphism (RFLP) methods to investigate the polymorphisms of 33 Y chromosome specific loci in 304 Chinese indigenous horses from 13 breeds. Consequently, two Y-single nucleotide polymorphisms (SNPs) (Y-45701/997 and Y-50869) and one Y-indel (Y-45288) were identified. Of those, the Y-50869 (T>A) revealed the highest variation frequency (24.67%), whereas it was only 3.29% and 1.97% in Y-45288 (T/-) and Y-45701/997 (G>T) locus, respectively. These three mutations accounted for 27.96% of the total samples and identified five Y-SNP haplotypes, demonstrating genetic diversity of Y chromosome in Chinese horses. In addition, all the five YSNP haplotypes were shared by different breeds. Among 13 horse breeds analyzed, Balikun horse displayed the highest nucleotide diversity (${\pi}=5.6{\times}10^{-4}$) and haplotype diversity (h = 0.527), while Ningqiang horse showed the lowest nucleotide diversity (${\pi}=0.00000$) and haplotype diversity (h = 0.000). The results also revealed that Chinese horses had a different polymorphic pattern of Y chromosome from European and American horses. In conclusion, Chinese horses revealed genetic diversity of Y chromosome, however more efforts should be made to better understand the domestication and paternal origin of Chinese indigenous horses.

Y-Single Nucleotide Polymorphisms Diversity in Chinese Indigenous Horse

Haoyuan Han,Qin Zhang,Kexin Gao,Xiangpeng Yue,Tao Zhang,Rui-Hua Dang,Xianyong Lan,Hong Chen,Chuzhao Lei 아세아·태평양축산학회 2015 Animal Bioscience Vol.28 No.8

In contrast to high genetic diversity of mitochondrial DNA (mtDNA), equine Y chromosome shows extremely low variability, implying limited patrilines in the domesticated horse. In this study, we applied direct sequencing and restriction fragment length polymorphism (RFLP) methods to investigate the polymorphisms of 33 Y chromosome specific loci in 304 Chinese indigenous horses from 13 breeds. Consequently, two Y-single nucleotide polymorphisms (SNPs) (Y-45701/997 and Y-50869) and one Y-indel (Y-45288) were identified. Of those, the Y-50869 (T>A) revealed the highest variation frequency (24.67%), whereas it was only 3.29% and 1.97% in Y-45288 (T/-) and Y-45701/997 (G>T) locus, respectively. These three mutations accounted for 27.96% of the total samples and identified five Y-SNP haplotypes, demonstrating genetic diversity of Y chromosome in Chinese horses. In addition, all the five Y-SNP haplotypes were shared by different breeds. Among 13 horse breeds analyzed, Balikun horse displayed the highest nucleotide diversity (π = 5.6×10‒4) and haplotype diversity (h = 0.527), while Ningqiang horse showed the lowest nucleotide diversity (π = 0.00000) and haplotype diversity (h = 0.000). The results also revealed that Chinese horses had a different polymorphic pattern of Y chromosome from European and American horses. In conclusion, Chinese horses revealed genetic diversity of Y chromosome, however more efforts should be made to better understand the domestication and paternal origin of Chinese indigenous horses.

Genome-Wide Association Study in East Asians Identifies Novel Susceptibility Loci for Breast Cancer

Long, Jirong,Cai, Qiuyin,Sung, Hyuna,Shi, Jiajun,Zhang, Ben,Choi, Ji-Yeob,Wen, Wanqing,Delahanty, Ryan J.,Lu, Wei,Gao, Yu-Tang,Shen, Hongbing,Park, Sue K.,Chen, Kexin,Shen, Chen-Yang,Ren, Zefang,Haima Public Library of Science 2012 PLoS genetics Vol.8 No.2

<P>Genetic factors play an important role in the etiology of both sporadic and familial breast cancer. We aimed to discover novel genetic susceptibility loci for breast cancer. We conducted a four-stage genome-wide association study (GWAS) in 19,091 cases and 20,606 controls of East-Asian descent including Chinese, Korean, and Japanese women. After analyzing 690,947 SNPs in 2,918 cases and 2,324 controls, we evaluated 5,365 SNPs for replication in 3,972 cases and 3,852 controls. Ninety-four SNPs were further evaluated in 5,203 cases and 5,138 controls, and finally the top 22 SNPs were investigated in up to 17,423 additional subjects (7,489 cases and 9,934 controls). SNP rs9485372, near the TGF-β activated kinase (<I>TAB2</I>) gene in chromosome 6q25.1, showed a consistent association with breast cancer risk across all four stages, with a <I>P</I>-value of 3.8×10<SUP>−12</SUP> in the combined analysis of all samples. Adjusted odds ratios (95% confidence intervals) were 0.89 (0.85–0.94) and 0.80 (0.75–0.86) for the A/G and A/A genotypes, respectively, compared with the genotype G/G. SNP rs9383951 (<I>P</I> = 1.9×10<SUP>−6</SUP> from the combined analysis of all samples), located in intron 5 of the <I>ESR1</I> gene, and SNP rs7107217 (<I>P</I> = 4.6×10<SUP>−7</SUP>), located at 11q24.3, also showed a consistent association in each of the four stages. This study provides strong evidence for a novel breast cancer susceptibility locus represented by rs9485372, near the <I>TAB2</I> gene (6q25.1), and identifies two possible susceptibility loci located in the <I>ESR1</I> gene and 11q24.3, respectively.</P><P><B>Author Summary</B></P> <P>Breast cancer is one of the most common malignancies among women worldwide. Genetic factors play an important role in the etiology of breast cancer. To identify common genetic susceptibility alleles for breast cancer, we performed a four-stage genome-wide association study in 19,091 cases and 20,606 controls among East-Asian women. Single nucleotide polymorphism (SNP) rs9485372, near the TGF-beta activated kinase 1 (<I>TAB2</I>) gene at chromosome 6q25.1, was associated with breast cancer risk (<I>P</I> = 3.8×10<SUP>−12</SUP>). SNPs rs9383951, located in intron 5 of the estrogen receptor 1 (<I>ESR1</I>) gene, and rs7107217, located at 11q24.3, were also consistently associated with breast cancer risk in all four stages with a combined <I>P</I> of 1.9×10<SUP>−6</SUP> and 4.6×10<SUP>−7</SUP>, respectively. This study provides strong evidence for a novel breast cancer susceptibility locus represented by rs9485372, near the <I>TAB2</I> gene (6q25.1), and identifies two possible susceptibility loci located in the <I>ESR1</I> gene and 11q24.3, respectively.</P>