Implementation of High Efficiency, High Lifetime and Low Cost Converter for an Automatic Photovoltaic Water Pumping Station

A novel idea of photovoltaic (PV) energy based converter for water pumping system without the USAge of fuel cells or batteries. In proposed system, the design of a three phase induction motor drive is directly supplied by using photovoltaic system energy. Presence of a three phase induction motor has better performance with optimized efficiency compared to the commercial water pumping system of DC motor. The developed resonant of Two Inductor Boost Converter (TIBC) and voltage quadruple with three phase Voltage Source Inverter (VSI) are based on the current fed multi resonant converter. Low input current ripple and high voltage gain are the features of TIBC. So the classical topology used to improve the system with a constant duty cycle control and a non dissipative snubber circuit along with a hysteresis controller to improve its efficiency. Due to the non existence of electrolytic capacitors the system is required to have a high lifetime and total system cost is low. As a result, in isolated locations the system has an optimistic solution and it provide water to poor societies

Improvement of Voltage output for Distribution System under Transient Condition with Dynamic Voltage Restorer

Abstract-Voltage sags and swells in the medium and low voltage distribution grid are considered to be the most frequent type of power quality problems based on recent power quality studies. Their impact on sensitive loads is severe. In this paper, the performance of voltage-source converter-based series compensators used for load voltage control in electrical power distribution network has been analyzed and compared, when a nonlinear load is connected across the load bus. Possible control schemes and their effects on the oscillation attenuation are also studied. Such studied control schemes include the commonly used single voltage loop control, voltage feedback plus reference feed forward control, and double-loop control with an outer voltage loop and an inner current loop. This research paper described DVR principles and voltage restoration methods for balanced and/or unbalanced voltage sags and swells in a distribution system. Simulation results were presented to illustrate and understand the performances of DVR under voltage sags/swells conditions. The MATLAB simulation verification of the results derived has been obtained using a model of the three-phase DVR

Genome sequence of Silicibacter pomeroyi reveals adaptations to the marine environment

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Sequence, annotation, and analysis of synteny between rice chromosome 3 and diverged grass species. The Rice Chromosome 3 Sequencing Consortium

Rice (Oryza sativa L.) chromosome 3 is evolutionarily conserved across the cultivated cereals and shares large blocks of synteny with maize and sorghum, which diverged from rice more than 50 million years ago. To begin to completely understand this chromosome, we sequenced, finished, and annotated 36.1 Mb (∼97%) from O. sativa subsp. japonica cv Nipponbare. Annotation features of the chromosome include 5915 genes, of which 913 are related to transposable elements. A putative function could be assigned to 3064 genes, with another 757 genes annotated as expressed, leaving 2094 that encode hypothetical proteins. Similarity searches against the proteome of Arabidopsis thaliana revealed putative homologs for 67% of the chromosome 3 proteins. Further searches of a nonredundant amino acid database, the Pfam domain database, plant Expressed Sequence Tags, and genomic assemblies from sorghum and maize revealed only 853 nontransposable element related proteins from chromosome 3 that lacked similarity to other known sequences. Interestingly, 426 of these have a paralog within the rice genome. A comparative physical map of the wild progenitor species, Oryza nivara, with japonica chromosome 3 revealed a high degree of sequence identity and synteny between these two species, which diverged ∼10,000 years ago. Although no major rearrangements were detected, the deduced size of the O. nivara chromosome 3 was 21% smaller than that of japonica. Synteny between rice and other cereals using an integrated maize physical map and wheat genetic map was strikingly high, further supporting the use of rice and, in particular, chromosome 3, as a model for comparative studies among the cereals

Genome sequence of Silicibacter pomeroyi reveals adaptations to the marine environment

Since the recognition of prokaryotes as essential components of the oceanic food web1, bacterioplankton have been acknowledged as catalysts of most major biogeochemical processes in the sea. Studying heterotrophic bacterioplankton has been challenging, however, as most major clades have never been cultured2 or have only been grown to low densities in sea water3,4. Here we describe the genome sequence of Silicibacter pomeroyi, a member of the marine Roseobacter clade (Fig. 1), the relatives of which comprise ∼10-20% of coastal and oceanic mixed-layer bacterioplankton2,5,6,7. This first genome sequence from any major heterotrophic clade consists of a chromosome (4,109,442 base pairs) and megaplasmid (491,611 base pairs). Genome analysis indicates that this organism relies upon a lithoheterotrophic strategy that uses inorganic compounds (carbon monoxide and sulphide) to supplement heterotrophy. Silicibacter pomeroyi also has genes advantageous for associations with plankton and suspended particles, including genes for uptake of algal-derived compounds, use of metabolites from reducing microzones, rapid growth and cell-density-dependent regulation. This bacterium has a physiology distinct from that of marine oligotrophs, adding a new strategy to the recognized repertoire for coping with a nutrient-poor ocean