283 research outputs found

    A NOVEL MULTIPHASE BIDIRECTIONAL FLY-BACK CONVERTER TOPOLOGY IS APPLIED TO INDUCTION MOTOR DRIVE

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    Hybrid Electric Vehicle (HEV) is an emerging technology in the modern world because of the fact that it mitigates environmental pollutions and at the same time increases fuel efficiency of the vehicles. Bi-directional Fly – back Converter controls electric drive of HEV of high power and enhances its performance which is the reflection of the fact that it can generate Constant voltages. For hybrid electric vehicles, the batteries and the drive dc link may be at different voltages. The batteries are at low voltage to obtain higher volumetric efficiencies, and the dc link is at higher voltage to have higher efficiency on the motor side. Therefore, a power interface between the batteries and the drive’s dc link is essential. This power interface should handle power flow from battery to motor, motor to battery, external gen-set to battery, and grid to battery. This paper proposes a multi-power-port topology which is capable of handling multiple power sources and still maintains simplicity and features like obtaining high gain, wide load variations, lower output-current ripple, and capability of parallel-battery energy due to the modular structure. The scheme incorporates a transformer winding technique which drastically reduces the leakage inductance of the coupled inductor. The development and testing of a bidirectional fly-back dc–dc converter for hybrid electric vehicle is described in this paper. Simple hysteresis voltage control is used for dc-link voltage regulation. The simulation results are presented, and modeling the circuit by using MATLAB/SIMULINK Platform

    Feeding stimulatory effects of Cyperus rotundus tuber on Cirrhinus mrigala

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    Traditionally tubers of cyperus (Cyperus rotundus) and its extracts have been used for alluring fish during harvesting in India. An experiment was conducted to evaluate its feeding stimulatory activity and effect on the growth of a commercially important freshwater fish, Cirrhinus mrigala. Three isonitrogenous and isocaloric formulated diets viz. plant ingredient based control and control supplemented with cyperus tuber (CS) at 1% and 5% levels were fed to the fingerlings of mrigal, C. mrigala (2.68+0.20 g) for a period of 45 days. The growth performance and the activity of metabolic enzymes, aspartate aminotransferase (AST) and alanine aminotransferase (ALT), in liver, gill and muscle tissues of mrigal were studied during every 15 days interval. Highest relative growth (72.28%) was obtained in the mrigal fed with the diet containing 5% cyperus (5% CS), while the relative growths were 66.18% and 43.40% for the fish fed with the 1% CS diet and control respectively. The activities of AST and ALT were significantly higher (p<0.01) in both 1% and 5% CS diets as compared to the control in all the tissues studied. Higher aminotransferase activities were observed in the tissues of 5% CS group than in those of 1% CS group throughout the experimental period. The observed higher enzymatic activity was concomitant with the higher growth rate in fish. The results suggested that cyperus tuber supplementation increased feed palatability and growth

    Implementation of phase imbalance scheme for stabilizing torsional oscillations

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    This paper implements the phase imbalance scheme for damping torsional oscillations of a series capacitor compensated power system. The IEEE Second Benchmark Model, system-1, wherein two turbine generator model and two system model connected to an infinite bus is employed as a standard system model to study the concept of subsynchronous resonance. The turbine generator models have a common torsional mode. The Electromagnetic Transients Program (EMTP) is employed to simulate the damping effects provided by the phase imbalance scheme. The simulation results also show that parallel phase imbalance scheme gives the better damping characteristics when compared to that of series phase imbalance scheme.DOI:http://dx.doi.org/10.11591/ijece.v4i5.629

    Phosphate Tether-Mediated Approach to the Formal Total Synthesis of (-)-Salicylihalamides A and B

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    A concise formal synthesis of the cytotoxic macrolides (-)-salicylihalamides A and B is reported. Key features of the synthetic strategy include a chemoselective hydroboration, highly regio- and diastereoselective methyl cuprate addition, Pd-catalyzed formate reduction, and an E-selective ring-closing metathesis to construct the 12-membered macrocycle subunit. Overall, two routes have been developed from a readily prepared bicyclic phosphate (4-steps), a 13-step route and a more efficient 9-step sequence relying on regioselective esterification of a key diol

    A Phosphate Tether-Mediated, One-pot, Sequential RCM/CM/Chemo-selective Hydrogenation Protocol

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    A versatile three-step, one-pot, sequential reaction protocol involving RCM, CM, and chemoselective hydrogenation is reported. This phosphate tether-mediated process occurs without intermediate isolation, is chemoselective and is governed by stereoelectronic properties innate to phosphate tethers, which ultimately act to preserve the integrity of the bisallylic, bicyclic phosphate for subsequent nucleophilic additions. Overall, this process can be used to efficiently generate advanced polyol synthons

    A Concise, Phosphate-Mediated Approach to the Total Synthesis of (−)-Tetrahydrolipstatin

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    An efficient synthesis of (−)-tetrahydrolipstatin (THL) is reported. This method takes advantage of a phosphate tether-mediated, one-pot, sequential RCM/CM/hydrogenation protocol to deliver THL in 8 total steps from a readily prepared (S,S)-triene. The strategy incorporates selective cross metathesis, regio-selective hydrogenation, regio- and diastereoselective cuprate addition and Mitsunobu inversion for installation of the C5 formamide ester subunit

    Imminent Rift Assortment Algorithm for Elevated Facet Data Using Wanton Collecting

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    Feature subset clustering is a powerful technique to reduce the dimensionality of feature vectors for text classification. In this paper, we propose a similarity-based self-constructing algorithm for feature clustering with the help of K-Means strategy. The words in the feature vector of a document set are grouped into clusters, based on similarity test. Words that are similar to each other are grouped into the same cluster, and make a head to each cluster data sets. By the FAST algorithm, the derived membership functions match closely with and describe properly the real distribution of the training data. Besides, the user need not specify the number of extracted features in advance, and trial-and-error for determining the appropriate number of extracted features can then be avoided. Experimental results show that our FAST algorithm implementation can run faster and obtain better-extracted features than other methods

    Coordination Control for Grid Connected Photovoltaic and Fuel Cell system

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    ABSTRACT: Power system plays important role for the generation of power from conventional sources, transmutation and distribution power at different consumer applications it will faces a so many problems. This can be overcome to implement the micro grid concept. The micro grid concept introduces the power is generated from the renewable energy sources like P.V Wind, Fuel cell, Micro Turbine etc will give signifying moment in near future. These power generating stations interconnected to form a micro grid system. IN this paper power generated from P.V and Fuel Cell (PEM). Here Both are the DC power generating stations for the purpose of power generating from the P.V in night time, rain session and cloud time face difficulties. this can be overcome to power is generating by using fuel cell and without any interruption of energy supplies to load and this system can interconnected to the utility grid and coordinately between these two system by using P-Q control theory in bidirectional converter system. This concept to reduces multiple reserve conversions and it will consists of both A.C and D.C networks connected to distribution generation through multi-bidirectional converters and to maintain stable operation of system by using proposed coordination schemes in the MATLAB simulink environment. KEYWORDS: micro grid, grid-tied mode, coordination control operations, PV system, Fuel Cell power generation. I.INTRODUCTION The ever increasing energy consumption, the soaring cost and the exhaustible nature of fossil fuel, and the worsening global environment have created increased interest in green [renewable based energy sources] power generation systems. Wind and solar power generation are two of the most promising renewable power generation technologies. The growth of wind and photovoltaic (PV) power generation systems has exceeded the most optimistic estimation. Nevertheless, because different alternative energy sources can complement each other to some extent, multisource hybrid alternative energy systems (with proper control) have great potential to provide higher quality and more reliable power to customers than a system based on a single resource. Because of this feature, hybrid energy systems have caught worldwide research attention A hybrid scheme consists of wind PV[3] array and fuel cell with power electronic convertors and power balancing controls are proposed in this paper for the purpose of reduces the reversible covert ions smooth power variation between sources and maintain stable operation in the system. The battery bank, which is charged during the daytime, will supply the inverter during the night to provide fuel cell necessary. when solar irradiation reaches its peak, the proposed scheme with appropriate choice of the sizes of the PV array and fuel cel

    Centrifugal Pump Impeller Modeling With Reverse Engineering

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    Abstract This project is about application of reverse engineering. Reverse engineering helps in obtaining the geometry of part or product which is not available otherwise. Its application makes it possible to reconstruct the original component with its drawing and manufacturing process. It is used in various fields but here the main application is related to broken impeller. In this present work a broken impeller of an old 0.5 hp motor taken. Currently this part is not available in the market as it is out dated and drawing of the component does not exist. As the part is no longer available it has to be made in-house so it will require all activities from designing to rapid prototyping. The procedure includes various stages which will help understand the different phases of reverse engineering. The process starts with understanding the reverse engineering procedure. The part geometry is first obtained with the help of scanning technology. Then with the use of different softwares, the three-dimensional image of the broken impeller is obtained. Once the image is obtained the part is optimized using ANSYS software. After the optimized geometry is obtained, the pattern of the part is obtained using Rapid prototyping machine. This can be used for casting of the original part
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