Electrical, Electronics and Computer Engineering,
Information Engineering and Technology,
Mechanical, Industrial and Manufacturing Engineering,
Automation and Mechatronics Engineering,
Material and Chemical Engineering,
Civil and Architecture Engineering,
Biotechnology and Bio Engineering,
Environmental Engineering,
Petroleum and Mining Engineering,
Marine and Agriculture engineering,
Aerospace Engineering.
Research Inventy : International Journal of Engineering and Science is published by the group of young academic and industrial researchers with 12 Issues per year. It is an online as well as print version open access journal that provides rapid publication (monthly) of articles in all areas of the subject such as: civil, mechanical, chemical, electronic and computer engineering as well as production and information technology. The Journal welcomes the submission of manuscripts that meet the general criteria of significance and scientific excellence. Papers will be published by rapid process within 20 days after acceptance and peer review process takes only 7 days. All articles published in Research Inventy will be peer-reviewed.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Welcome to International Journal of Engineering Research and Development (IJERD)IJERD Editor
journal publishing, how to publish research paper, Call For research paper, international journal, publishing a paper, IJERD, journal of science and technology, how to get a research paper published, publishing a paper, publishing of journal, publishing of research paper, reserach and review articles, IJERD Journal, How to publish your research paper, publish research paper, open access engineering journal, Engineering journal, Mathemetics journal, Physics journal, Chemistry journal, Computer Engineering, Computer Science journal, how to submit your paper, peer reviw journal, indexed journal, reserach and review articles, engineering journal, www.ijerd.com, research journals,
yahoo journals, bing journals, International Journal of Engineering Research and Development, google journals, hard copy of journal
Research Inventy : International Journal of Engineering and Science is published by the group of young academic and industrial researchers with 12 Issues per year. It is an online as well as print version open access journal that provides rapid publication (monthly) of articles in all areas of the subject such as: civil, mechanical, chemical, electronic and computer engineering as well as production and information technology. The Journal welcomes the submission of manuscripts that meet the general criteria of significance and scientific excellence. Papers will be published by rapid process within 20 days after acceptance and peer review process takes only 7 days. All articles published in Research Inventy will be peer-reviewed.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Welcome to International Journal of Engineering Research and Development (IJERD)IJERD Editor
journal publishing, how to publish research paper, Call For research paper, international journal, publishing a paper, IJERD, journal of science and technology, how to get a research paper published, publishing a paper, publishing of journal, publishing of research paper, reserach and review articles, IJERD Journal, How to publish your research paper, publish research paper, open access engineering journal, Engineering journal, Mathemetics journal, Physics journal, Chemistry journal, Computer Engineering, Computer Science journal, how to submit your paper, peer reviw journal, indexed journal, reserach and review articles, engineering journal, www.ijerd.com, research journals,
yahoo journals, bing journals, International Journal of Engineering Research and Development, google journals, hard copy of journal
A Five – Level Integrated AC – DC ConverterIJTET Journal
This paper presents the implementation of a new five – level integrated AC – DC converter with high input power factor and reduced input current harmonics complied with IEC1000-3-2 harmonic standards for electrical equipments. The proposed topology is a combination of boost input power factor pre – regulator and five – level DC – DC converter. The single – stage PFC (SSPFC) approach used in this topology is an alternative solution to low – power and cost – effective applications.
IOSR Journal of Electrical and Electronics Engineering(IOSR-JEEE) is an open access international journal that provides rapid publication (within a month) of articles in all areas of electrical and electronics engineering and its applications. The journal welcomes publications of high quality papers on theoretical developments and practical applications in electrical and electronics engineering. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
Novel Single Phase Full Bridge Inverter Formed by Floating CapacitorsIAES-IJPEDS
In this paper, a new single-phase bridge inverter is described which can
generate a more steps of voltage levels with reduced number of switches,
gate driver circuits and diodes as compare to normal multilevel inverter.
Another feature of this inverter is its ability to prodeuce the voltages from a
single dc-link power supply which enables back-to-back operation of
converter. The proposed method with more number of levels can improve
power quality, lower switching losses and produce high quality voltage
waveforms. Moreover at all load power factors the proposed method can be
operated.The research of the model is done by means of computer simulation
with the software MATLAB/SIMULINK. This topology has very low
common mode voltage variation and dv/dt stress. Also this inverter is help
full for reactive power compensation.
Design and Control for the Buck-Boost Converter Combining 1-Plus-D Converter ...IJPEDS-IAES
In this paper, a design and control for the buck-boost converter, i.e., 1-plus-D
converter with a positive output voltage, is presented, which combines the 1-
plus-D converter and the synchronous rectified (SR) buck converter. By
doing so, the problem in voltage bucking of the 1-plus-D converter can be
solved, thereby increasing the application capability of the 1-plus-D
converter. Since such a converter operates in continuous conduction mode
inherently, it possesses the nonpulsating output current, thereby not only
decreasing the current stress on the output capacitor but also reducing the
output voltage ripple. Above all, both the 1-plus-D converter and the SR
buck converter, combined into a buck–boost converter with no right-half
plane zero, use the same power switches, thereby causing the required circuit
to be compact and the corresponding cost to be down. Furthermore, during
the magnetization period, the input voltage of the 1-plus-D converter comes
from the input voltage source, whereas during the demagnetization period,
the input voltage of the 1-plus-D converter comes from the output voltage of
the SR buck converter.
Analysis of SEPIC for PV-Applications using PI Controller and Current Mode Co...ijsrd.com
A SEPIC (single-Ended Primary Inductor Converter) DC-DC converter is capable of operating in either step-up or step-down mode and widely used in battery-operated equipment. This paper presents two various closed loop techniques of SEPIC Converter, namely current mode control and PI control using PV panel. For PI controller voltage is taken as reference, for current mode controller current has taken as reference, by using the current mode controller chaos has also controlled.
International Journal of Engineering Research and Development (IJERD)IJERD Editor
journal publishing, how to publish research paper, Call For research paper, international journal, publishing a paper, IJERD, journal of science and technology, how to get a research paper published, publishing a paper, publishing of journal, publishing of research paper, reserach and review articles, IJERD Journal, How to publish your research paper, publish research paper, open access engineering journal, Engineering journal, Mathemetics journal, Physics journal, Chemistry journal, Computer Engineering, Computer Science journal, how to submit your paper, peer reviw journal, indexed journal, reserach and review articles, engineering journal, www.ijerd.com, research journals,
yahoo journals, bing journals, International Journal of Engineering Research and Development, google journals, hard copy of journal
Welcome to International Journal of Engineering Research and Development (IJERD)IJERD Editor
call for paper 2012, hard copy of journal, research paper publishing, where to publish research paper,
journal publishing, how to publish research paper, Call For research paper, international journal, publishing a paper, IJERD, journal of science and technology, how to get a research paper published, publishing a paper, publishing of journal, publishing of research paper, reserach and review articles, IJERD Journal, How to publish your research paper, publish research paper, open access engineering journal, Engineering journal, Mathemetics journal, Physics journal, Chemistry journal, Computer Engineering, Computer Science journal, how to submit your paper, peer reviw journal, indexed journal, reserach and review articles, engineering journal, www.ijerd.com, research journals
International Journal of Engineering Research and DevelopmentIJERD Editor
Electrical, Electronics and Computer Engineering,
Information Engineering and Technology,
Mechanical, Industrial and Manufacturing Engineering,
Automation and Mechatronics Engineering,
Material and Chemical Engineering,
Civil and Architecture Engineering,
Biotechnology and Bio Engineering,
Environmental Engineering,
Petroleum and Mining Engineering,
Marine and Agriculture engineering,
Aerospace Engineering.
Welcome to International Journal of Engineering Research and Development (IJERD)IJERD Editor
call for paper 2012, hard copy of journal, research paper publishing, where to publish research paper,
journal publishing, how to publish research paper, Call For research paper, international journal, publishing a paper, IJERD, journal of science and technology, how to get a research paper published, publishing a paper, publishing of journal, publishing of research paper, reserach and review articles, IJERD Journal, How to publish your research paper, publish research paper, open access engineering journal, Engineering journal, Mathemetics journal, Physics journal, Chemistry journal, Computer Engineering, Computer Science journal, how to submit your paper, peer reviw journal, indexed journal, reserach and review articles, engineering journal, www.ijerd.com, research journals
Welcome to International Journal of Engineering Research and Development (IJERD)IJERD Editor
call for paper 2012, hard copy of journal, research paper publishing, where to publish research paper,
journal publishing, how to publish research paper, Call For research paper, international journal, publishing a paper, IJERD, journal of science and technology, how to get a research paper published, publishing a paper, publishing of journal, publishing of research paper, reserach and review articles, IJERD Journal, How to publish your research paper, publish research paper, open access engineering journal, Engineering journal, Mathemetics journal, Physics journal, Chemistry journal, Computer Engineering, Computer Science journal, how to submit your paper, peer reviw journal, indexed journal, reserach and review articles, engineering journal, www.ijerd.com, research journals
A Five – Level Integrated AC – DC ConverterIJTET Journal
This paper presents the implementation of a new five – level integrated AC – DC converter with high input power factor and reduced input current harmonics complied with IEC1000-3-2 harmonic standards for electrical equipments. The proposed topology is a combination of boost input power factor pre – regulator and five – level DC – DC converter. The single – stage PFC (SSPFC) approach used in this topology is an alternative solution to low – power and cost – effective applications.
IOSR Journal of Electrical and Electronics Engineering(IOSR-JEEE) is an open access international journal that provides rapid publication (within a month) of articles in all areas of electrical and electronics engineering and its applications. The journal welcomes publications of high quality papers on theoretical developments and practical applications in electrical and electronics engineering. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
Novel Single Phase Full Bridge Inverter Formed by Floating CapacitorsIAES-IJPEDS
In this paper, a new single-phase bridge inverter is described which can
generate a more steps of voltage levels with reduced number of switches,
gate driver circuits and diodes as compare to normal multilevel inverter.
Another feature of this inverter is its ability to prodeuce the voltages from a
single dc-link power supply which enables back-to-back operation of
converter. The proposed method with more number of levels can improve
power quality, lower switching losses and produce high quality voltage
waveforms. Moreover at all load power factors the proposed method can be
operated.The research of the model is done by means of computer simulation
with the software MATLAB/SIMULINK. This topology has very low
common mode voltage variation and dv/dt stress. Also this inverter is help
full for reactive power compensation.
Design and Control for the Buck-Boost Converter Combining 1-Plus-D Converter ...IJPEDS-IAES
In this paper, a design and control for the buck-boost converter, i.e., 1-plus-D
converter with a positive output voltage, is presented, which combines the 1-
plus-D converter and the synchronous rectified (SR) buck converter. By
doing so, the problem in voltage bucking of the 1-plus-D converter can be
solved, thereby increasing the application capability of the 1-plus-D
converter. Since such a converter operates in continuous conduction mode
inherently, it possesses the nonpulsating output current, thereby not only
decreasing the current stress on the output capacitor but also reducing the
output voltage ripple. Above all, both the 1-plus-D converter and the SR
buck converter, combined into a buck–boost converter with no right-half
plane zero, use the same power switches, thereby causing the required circuit
to be compact and the corresponding cost to be down. Furthermore, during
the magnetization period, the input voltage of the 1-plus-D converter comes
from the input voltage source, whereas during the demagnetization period,
the input voltage of the 1-plus-D converter comes from the output voltage of
the SR buck converter.
Analysis of SEPIC for PV-Applications using PI Controller and Current Mode Co...ijsrd.com
A SEPIC (single-Ended Primary Inductor Converter) DC-DC converter is capable of operating in either step-up or step-down mode and widely used in battery-operated equipment. This paper presents two various closed loop techniques of SEPIC Converter, namely current mode control and PI control using PV panel. For PI controller voltage is taken as reference, for current mode controller current has taken as reference, by using the current mode controller chaos has also controlled.
International Journal of Engineering Research and Development (IJERD)IJERD Editor
journal publishing, how to publish research paper, Call For research paper, international journal, publishing a paper, IJERD, journal of science and technology, how to get a research paper published, publishing a paper, publishing of journal, publishing of research paper, reserach and review articles, IJERD Journal, How to publish your research paper, publish research paper, open access engineering journal, Engineering journal, Mathemetics journal, Physics journal, Chemistry journal, Computer Engineering, Computer Science journal, how to submit your paper, peer reviw journal, indexed journal, reserach and review articles, engineering journal, www.ijerd.com, research journals,
yahoo journals, bing journals, International Journal of Engineering Research and Development, google journals, hard copy of journal
Welcome to International Journal of Engineering Research and Development (IJERD)IJERD Editor
call for paper 2012, hard copy of journal, research paper publishing, where to publish research paper,
journal publishing, how to publish research paper, Call For research paper, international journal, publishing a paper, IJERD, journal of science and technology, how to get a research paper published, publishing a paper, publishing of journal, publishing of research paper, reserach and review articles, IJERD Journal, How to publish your research paper, publish research paper, open access engineering journal, Engineering journal, Mathemetics journal, Physics journal, Chemistry journal, Computer Engineering, Computer Science journal, how to submit your paper, peer reviw journal, indexed journal, reserach and review articles, engineering journal, www.ijerd.com, research journals
International Journal of Engineering Research and DevelopmentIJERD Editor
Electrical, Electronics and Computer Engineering,
Information Engineering and Technology,
Mechanical, Industrial and Manufacturing Engineering,
Automation and Mechatronics Engineering,
Material and Chemical Engineering,
Civil and Architecture Engineering,
Biotechnology and Bio Engineering,
Environmental Engineering,
Petroleum and Mining Engineering,
Marine and Agriculture engineering,
Aerospace Engineering.
Welcome to International Journal of Engineering Research and Development (IJERD)IJERD Editor
call for paper 2012, hard copy of journal, research paper publishing, where to publish research paper,
journal publishing, how to publish research paper, Call For research paper, international journal, publishing a paper, IJERD, journal of science and technology, how to get a research paper published, publishing a paper, publishing of journal, publishing of research paper, reserach and review articles, IJERD Journal, How to publish your research paper, publish research paper, open access engineering journal, Engineering journal, Mathemetics journal, Physics journal, Chemistry journal, Computer Engineering, Computer Science journal, how to submit your paper, peer reviw journal, indexed journal, reserach and review articles, engineering journal, www.ijerd.com, research journals
Welcome to International Journal of Engineering Research and Development (IJERD)IJERD Editor
call for paper 2012, hard copy of journal, research paper publishing, where to publish research paper,
journal publishing, how to publish research paper, Call For research paper, international journal, publishing a paper, IJERD, journal of science and technology, how to get a research paper published, publishing a paper, publishing of journal, publishing of research paper, reserach and review articles, IJERD Journal, How to publish your research paper, publish research paper, open access engineering journal, Engineering journal, Mathemetics journal, Physics journal, Chemistry journal, Computer Engineering, Computer Science journal, how to submit your paper, peer reviw journal, indexed journal, reserach and review articles, engineering journal, www.ijerd.com, research journals
International Journal of Engineering Research and Development (IJERD)IJERD Editor
International Journal of Engineering Research and Development is an international premier peer reviewed open access engineering and technology journal promoting the discovery, innovation, advancement and dissemination of basic and transitional knowledge in engineering, technology and related disciplines.
Welcome to International Journal of Engineering Research and Development (IJERD)IJERD Editor
call for paper 2012, hard copy of journal, research paper publishing, where to publish research paper,
journal publishing, how to publish research paper, Call For research paper, international journal, publishing a paper, IJERD, journal of science and technology, how to get a research paper published, publishing a paper, publishing of journal, publishing of research paper, reserach and review articles, IJERD Journal, How to publish your research paper, publish research paper, open access engineering journal, Engineering journal, Mathemetics journal, Physics journal, Chemistry journal, Computer Engineering, Computer Science journal, how to submit your paper, peer reviw journal, indexed journal, reserach and review articles, engineering journal, www.ijerd.com, research journals
Research Inventy : International Journal of Engineering and Science is published by the group of young academic and industrial researchers with 12 Issues per year. It is an online as well as print version open access journal that provides rapid publication (monthly) of articles in all areas of the subject such as: civil, mechanical, chemical, electronic and computer engineering as well as production and information technology. The Journal welcomes the submission of manuscripts that meet the general criteria of significance and scientific excellence. Papers will be published by rapid process within 20 days after acceptance and peer review process takes only 7 days. All articles published in Research Inventy will be peer-reviewed.
Research Inventy : International Journal of Engineering and Science is published by the group of young academic and industrial researchers with 12 Issues per year. It is an online as well as print version open access journal that provides rapid publication (monthly) of articles in all areas of the subject such as: civil, mechanical, chemical, electronic and computer engineering as well as production and information technology. The Journal welcomes the submission of manuscripts that meet the general criteria of significance and scientific excellence. Papers will be published by rapid process within 20 days after acceptance and peer review process takes only 7 days. All articles published in Research Inventy will be peer-reviewed.
Review of Step down Converter with Efficient ZVS OperationIJRST Journal
This paper presents the review of step down converter with efficient ZVS operation. The designed buck converter uses ZCS technique and the function is realized so that the power form is converted from 12V DC 5V DC (1A). A detailed analysis of zero current switching buck converters is performed and a mathematical analysis of the mode of operation is also presented. In order to reduce the switching losses in associated with conventional converters; resonant inductor and resonant capacitor (LC resonant circuit) is applied which helps to turn on-off the switch at zero current. The dc-dc buck converter receives the energy from the input source, when the switch is turned-on. The buck–buck converters have characteristics that warrant a more detailed study. The buck converters under discontinuous conduction mode /continuous conduction mode boundary.
NON-ISOLATED SOFT SWITCHING DC-DC CONVERTER AND LOAD AT FULL RANGE OF ZVS IAEME Publication
A non isolated soft switching DC–DC converter and load at full range of zero-voltage
switching (ZVS) characteristic is proposed. The proposed converter consists of an auxiliary circuit,
an inductor, two switches, and 2 diodes to achieving high efficiency at full range of load. At low
and heavy loads, ZVS of switching device is achieved by energy storing component. The inductor
energy stored varies with load and hence results in minimizes conduction loss. This leads to
switching of device for full range of load. The proposed DC - DC converter achieves high
efficiency as switching loss is reduced due to soft switching and ZVS operation which severe to
reduce conduction loss. The efficiency is improved about 4% in boost mode (2.5% in buck mode) at
full range of load. To verify the performance of the proposed converter, experimental results
prototype are presented.
Interleaved High Step-Down Synchronous Convertertheijes
For low output voltage, high output current systems applications, Synchronous switching power converters give better performance than non synchronous converters. This paper presents an interleaved synchronous buck converter which has low switch voltage stress with high conversion ratio. The input current can be shared among the inductors so that high reliability and efficiency can be obtained and ripples also reduced, the converter performance can be improved. Thus converter features automatic uniform current sharing characteristic of the interleaved phases without adding extra circuitry or complex control methods. Capacitors switching circuits are combined with interleaved four-phase buck converter for getting a high step-down conversion ratio without adopting an extreme short duty ratio. Synchronous rectifier technology is adopted to increase the converter efficiency. A 30V input voltage, 1.8V output voltage, circuit is simulated to verify the performance. The simulation is done in MATLAB/SIMULINK R2012a.
Research Inventy : International Journal of Engineering and Science is published by the group of young academic and industrial researchers with 12 Issues per year. It is an online as well as print version open access journal that provides rapid publication (monthly) of articles in all areas of the subject such as: civil, mechanical, chemical, electronic and computer engineering as well as production and information technology. The Journal welcomes the submission of manuscripts that meet the general criteria of significance and scientific excellence. Papers will be published by rapid process within 20 days after acceptance and peer review process takes only 7 days. All articles published in Research Inventy will be peer-reviewed.
Fuzzy Control Based Quadrupler Boost ConverterIJSRD
A voltage quadruple boost converter is presented. This converter is used to obtain higher voltage gain and reduces the voltage stress across the switches and diodes. These voltage multipliers are used in high voltage, low current applications such as for accelerating purpose in a cathode ray tube and also this converter topology is advanced than previous dc-dc converters. Voltage quadruple converter uses parallel-input series-output connection. Comparing with two phase interleaved boost converter one can see that two more capacitors and two more diodes are added so that during the energy transfer period partial inductor stored energy is stored in one capacitor and partial inductor stored energy together with the other capacitor store energy is transferred to the output to achieve much higher voltage gain. However, the proposed voltage gain is twice that of the interleaved two-phase boost converter. Simulation of the converter is carried out using MATLAB/SIMULINK software. The converter is simulated using fuzzy logic control and also the experimental setup was done.
Extremely high duty cycle of boost converter may result in higher conduction losses. To achieve a high
conversion ratio without operating at extremely high duty ratio, some converters based on transformers or coupled
inductors or tapped inductors have been provided. However, the leakage inductance in the transformer, coupled
inductor or tapped inductor will cause high voltage spikes in the switches and reduce system efficiency. A novel
single switch cascaded dc-dc converter of boost and buck boost converters have extended voltage conversion ratio
to d/(1-d)2. The features of the converter are high voltage gain; only one switch for realizing the converter, the
number of magnetic components is small etc. So comparing with other topologies cascaded converter is more
effective. Simulation of the converter for a dc input voltage and fixed duty cycle was done, and the same was
verified experimentally for a low input voltage. The software used for simulation was MatlabR2014a
A Novel Method for Prevention of Bandwidth Distributed Denial of Service AttacksIJERD Editor
Distributed Denial of Service (DDoS) Attacks became a massive threat to the Internet. Traditional
Architecture of internet is vulnerable to the attacks like DDoS. Attacker primarily acquire his army of Zombies,
then that army will be instructed by the Attacker that when to start an attack and on whom the attack should be
done. In this paper, different techniques which are used to perform DDoS Attacks, Tools that were used to
perform Attacks and Countermeasures in order to detect the attackers and eliminate the Bandwidth Distributed
Denial of Service attacks (B-DDoS) are reviewed. DDoS Attacks were done by using various Flooding
techniques which are used in DDoS attack.
The main purpose of this paper is to design an architecture which can reduce the Bandwidth
Distributed Denial of service Attack and make the victim site or server available for the normal users by
eliminating the zombie machines. Our Primary focus of this paper is to dispute how normal machines are
turning into zombies (Bots), how attack is been initiated, DDoS attack procedure and how an organization can
save their server from being a DDoS victim. In order to present this we implemented a simulated environment
with Cisco switches, Routers, Firewall, some virtual machines and some Attack tools to display a real DDoS
attack. By using Time scheduling, Resource Limiting, System log, Access Control List and some Modular
policy Framework we stopped the attack and identified the Attacker (Bot) machines
Hearing loss is one of the most common human impairments. It is estimated that by year 2015 more
than 700 million people will suffer mild deafness. Most can be helped by hearing aid devices depending on the
severity of their hearing loss. This paper describes the implementation and characterization details of a dual
channel transmitter front end (TFE) for digital hearing aid (DHA) applications that use novel micro
electromechanical- systems (MEMS) audio transducers and ultra-low power-scalable analog-to-digital
converters (ADCs), which enable a very-low form factor, energy-efficient implementation for next-generation
DHA. The contribution of the design is the implementation of the dual channel MEMS microphones and powerscalable
ADC system.
Influence of tensile behaviour of slab on the structural Behaviour of shear c...IJERD Editor
-A composite beam is composed of a steel beam and a slab connected by means of shear connectors
like studs installed on the top flange of the steel beam to form a structure behaving monolithically. This study
analyzes the effects of the tensile behavior of the slab on the structural behavior of the shear connection like slip
stiffness and maximum shear force in composite beams subjected to hogging moment. The results show that the
shear studs located in the crack-concentration zones due to large hogging moments sustain significantly smaller
shear force and slip stiffness than the other zones. Moreover, the reduction of the slip stiffness in the shear
connection appears also to be closely related to the change in the tensile strain of rebar according to the increase
of the load. Further experimental and analytical studies shall be conducted considering variables such as the
reinforcement ratio and the arrangement of shear connectors to achieve efficient design of the shear connection
in composite beams subjected to hogging moment.
Gold prospecting using Remote Sensing ‘A case study of Sudan’IJERD Editor
Gold has been extracted from northeast Africa for more than 5000 years, and this may be the first
place where the metal was extracted. The Arabian-Nubian Shield (ANS) is an exposure of Precambrian
crystalline rocks on the flanks of the Red Sea. The crystalline rocks are mostly Neoproterozoic in age. ANS
includes the nations of Israel, Jordan. Egypt, Saudi Arabia, Sudan, Eritrea, Ethiopia, Yemen, and Somalia.
Arabian Nubian Shield Consists of juvenile continental crest that formed between 900 550 Ma, when intra
oceanic arc welded together along ophiolite decorated arc. Primary Au mineralization probably developed in
association with the growth of intra oceanic arc and evolution of back arc. Multiple episodes of deformation
have obscured the primary metallogenic setting, but at least some of the deposits preserve evidence that they
originate as sea floor massive sulphide deposits.
The Red Sea Hills Region is a vast span of rugged, harsh and inhospitable sector of the Earth with
inimical moon-like terrain, nevertheless since ancient times it is famed to be an abode of gold and was a major
source of wealth for the Pharaohs of ancient Egypt. The Pharaohs old workings have been periodically
rediscovered through time. Recent endeavours by the Geological Research Authority of Sudan led to the
discovery of a score of occurrences with gold and massive sulphide mineralizations. In the nineties of the
previous century the Geological Research Authority of Sudan (GRAS) in cooperation with BRGM utilized
satellite data of Landsat TM using spectral ratio technique to map possible mineralized zones in the Red Sea
Hills of Sudan. The outcome of the study mapped a gossan type gold mineralization. Band ratio technique was
applied to Arbaat area and a signature of alteration zone was detected. The alteration zones are commonly
associated with mineralization. The alteration zones are commonly associated with mineralization. A filed check
confirmed the existence of stock work of gold bearing quartz in the alteration zone. Another type of gold
mineralization that was discovered using remote sensing is the gold associated with metachert in the Atmur
Desert.
Reducing Corrosion Rate by Welding DesignIJERD Editor
The paper addresses the importance of welding design to prevent corrosion at steel. Welding is
used to join pipe, profiles at bridges, spindle, and a lot more part of engineering construction. The
problems happened associated with welding are common issues in these fields, especially corrosion.
Corrosion can be reduced with many methods, they are painting, controlling humidity, and also good
welding design. In the research, it can be found that reducing residual stress on the welding can be
solved in corrosion rate reduction problem.
Preheating on 500oC and 600oC give better condition to reduce corosion rate than condition after
preheating 400oC. For all welding groove type, material with 500oC and 600oC preheating after 14 days
corrosion test is 0,5%-0,69% lost. Material with 400oC preheating after 14 days corrosion test is 0,57%-0,76%
lost.
Welding groove also influence corrosion rate. X and V type welding groove give better condition to reduce
corrosion rate than use 1/2V and 1/2 X welding groove. After 14 days corrosion test, the samples with
X welding groove type is 0,5%-0,57% lost. The samples with V welding groove after 14 days corrosion test is
0,51%-0,59% lost. The samples with 1/2V and 1/2X welding groove after 14 days corrosion test is 0,58%-
0,71% lost.
Router 1X3 – RTL Design and VerificationIJERD Editor
Routing is the process of moving a packet of data from source to destination and enables messages
to pass from one computer to another and eventually reach the target machine. A router is a networking device
that forwards data packets between computer networks. It is connected to two or more data lines from different
networks (as opposed to a network switch, which connects data lines from one single network). This paper,
mainly emphasizes upon the study of router device, it‟s top level architecture, and how various sub-modules of
router i.e. Register, FIFO, FSM and Synchronizer are synthesized, and simulated and finally connected to its top
module.
Active Power Exchange in Distributed Power-Flow Controller (DPFC) At Third Ha...IJERD Editor
This paper presents a component within the flexible ac-transmission system (FACTS) family, called
distributed power-flow controller (DPFC). The DPFC is derived from the unified power-flow controller (UPFC)
with an eliminated common dc link. The DPFC has the same control capabilities as the UPFC, which comprise
the adjustment of the line impedance, the transmission angle, and the bus voltage. The active power exchange
between the shunt and series converters, which is through the common dc link in the UPFC, is now through the
transmission lines at the third-harmonic frequency. DPFC multiple small-size single-phase converters which
reduces the cost of equipment, no voltage isolation between phases, increases redundancy and there by
reliability increases. The principle and analysis of the DPFC are presented in this paper and the corresponding
simulation results that are carried out on a scaled prototype are also shown.
Mitigation of Voltage Sag/Swell with Fuzzy Control Reduced Rating DVRIJERD Editor
Power quality has been an issue that is becoming increasingly pivotal in industrial electricity
consumers point of view in recent times. Modern industries employ Sensitive power electronic equipments,
control devices and non-linear loads as part of automated processes to increase energy efficiency and
productivity. Voltage disturbances are the most common power quality problem due to this the use of a large
numbers of sophisticated and sensitive electronic equipment in industrial systems is increased. This paper
discusses the design and simulation of dynamic voltage restorer for improvement of power quality and
reduce the harmonics distortion of sensitive loads. Power quality problem is occurring at non-standard
voltage, current and frequency. Electronic devices are very sensitive loads. In power system voltage sag,
swell, flicker and harmonics are some of the problem to the sensitive load. The compensation capability
of a DVR depends primarily on the maximum voltage injection ability and the amount of stored
energy available within the restorer. This device is connected in series with the distribution feeder at
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International Journal of Engineering Research and Development
1. International Journal of Engineering Research and Development
e-ISSN: 2278-067X, p-ISSN: 2278-800X, www.ijerd.com
Volume 10, Issue 1 (February 2014), PP. 16-21
16
A Novel Interleaved Buck Converter with Closed Loop Control
Arya Raveendran1
, Geetha B2
, Annie P Oommen3
1
P.G. Student, Mar Athanasius College of Engineering, Kothamangalam, Kerala
2,3
Professor, Mar Athanasius College of Engineering, Kothamangalam, Kerala
Abstract:- The paper presents a new Interleaved Buck Converter with feedback control. Closed loop control
provides a good regulated output voltage. Proposed IBC is suitable for application where input voltage is high
and operating duty cycle is less than 50%.In this IBC two active switches are connected in series and a coupling
capacitor is employed in the power path. It shows that the voltage stress across all the active switches is half of
the input voltage before turn-on or after turn-off when the operating duty is below 50%. So the capacitive
discharging and switching losses can be reduced considerably. It allows proposed IBC to have higher efficiency
and operate with higher switching frequency. In addition, the proposed IBC has a higher step-down conversion
ratio and a smaller output current ripple compared with a conventional IBC. Simulation can be carried out to
study the performance of the proposed topology in MATLAB/SIMULINK environment. With closed loop
control a better output voltage is obtained.
Keywords:- Interleaved , Buck, PWM ,Closed loop
I. INTRODUCTION
Interleaving technique connects dc-dc converter in parallel to share the power flow between two or
more conversion chains. It implies a reduction in the size, weight and volume of the inductors and capacitors.
Also a proper control of the parallel converters increases the ripple frequency and reduces the ripple waveforms
at the input and output of the power conversion system, which leads to a significant reduction of current and
voltage ripples.[6 7]
This paper presents new topology of interleaved buck converter. Due to the simple structure and low
control complexity of interleaved buck converter, it is used in applications where non isolation, step down
conversion ratio, high output current with low ripple is required. But in conventional IBC, the active switches
suffer from the input source voltage due to its parallel connection with the source. So high voltage devices
should be used. But high voltage rated devices is characterized with high forward voltage drop, high cost,
intense reverse recover y, high on resistance. Due to the hard switching condition, the operating efficiency is
very poor. For getting good dynamics and higher power density converter requires to operate at higher switching
frequency. But at higher switching frequency switching losses is increased and thus, efficiency is further
reduced.[1]
Fig.1.Conventional Interleaved Buck Converter
2. A Novel Interleaved Buck Converter with Closed Loop Control
17
II. PROPOSED CIRCUIT WITHOUT FEEDBACK
Fig.2.Proposed Interleaved Buck Converter without feedback
In the proposed IBC two switches are connected in series and there is a coupling capacitor in the power
path. The two switches Q1 and Q2 are activated with a phase shift angle of 180º.The output voltage can be
regulated by adjusting the duty cycle at fixed switching frequency. The new IBC is operates at continuous
conduction mode .So its current stress is low. The voltage stress of active switches is half of the input voltage
before turn on and after turn off under steady state. So the capacitive discharging and switching losses reduces
considerably. The voltage stress of freewheeling diode is also considerably reduced. So the reverse recovery and
conduction losses on the freewheeling diode improve by using schottky diode which have generally low break
down voltage. A good conversion ratio and low output current ripple can be obtained with proposed topology.
The new IBC is suitable for applications where the input voltage is high and duty cycle is less than 50%[5].
A. Circuit Operations
One switching period is divided into four modes. For illustrating the operation of IBC ,there are certain
assumptions are made such that, the two inductance L1 and L2 have the same inductance, all power
semiconductor devices are ideal, the coupling capacitor CB and output capacitor CO is large enough to be
considered as voltage source.
Steady-State Operation when D≤0.5
Mode 1 [t0 –t1 ]: Mode 1 starts with Q1 is turned on at t0 . Then, the current of L1 , flows through Q1 ,
CB , and L1 and the voltage of the coupling capacitor VCB is charged. The current of L2 , freewheels through D2 .
.
Mode 2 [t1 –t2 ]: Mode 2 starts when Q1 is turned off at t1 . The current of L1 and L2 freewheel through D1 and
D2, respectively.
Mode 3 [t2 –t3 ]: Mode 3 starts when Q2 is turned on at t2 . At this same time, D2 is turned off. The current, iL 1
freewheels through D1 and iL 2 flows through D1 , CB , Q2 , and L2.Thus, VCB is discharged.
Mode 4 [t3 –t4 ]: Mode 4 starts when Q2 is turned off at t3 , and its operation is the same with that of mode 2.
The switching states and voltage across different components during different modes are given in table 1
The steady-state operation of the proposed IBC operating with the duty cycle of D ≤ 0.5 has been
described. From the working principles, it is clear that the voltage stress of all semiconductor devices except Q2
is not the input voltage, but is determined by the voltage of coupling capacitor VCB. The maximum voltage of Q2
is the input voltage, but the voltage before turn-on or after turn-off is equal to VCB. As these results, the
capacitive discharging and switching losses on Q1 and Q2 can be reduced considerably. Also diodes with good
characteristics such as schottky can be used for D1 and D2 , the reverse-recovery and conduction losses can be
also improved.
(a)Mode 1
3. A Novel Interleaved Buck Converter with Closed Loop Control
18
(b) Mode 2 or 4
(C)Mode 3
Fig.3.Circuit operations of proposed IBC for D<.5
Table.1.Switching states and voltage during D<.5
Mode Q1 Q2 VQ1 VQ2 VL1 VL2 VD1 VD2
MODE1 ON OFF 0 VS VS-VCB-VO -VO VS-VCB 0
MODE2 OFF OFF V S -VCB VCB -VO -VO 0 0
MODE3 OFF ON VS-VCB 0 -VO VCB-VO 0 VCB
MODE4 OFF OFF V S -VCB VCB -VO -VO 0 0
Steady-State Operation when D > 0.5
Mode 1 [t0 –t1 ]: Mode 1 starts when Q2 is in on-state andQ1 is turned on at t0 . Then, iL 1 flows through
Q1 , CB , and L1 and VCB is charged. iL 2 (t) flows through Q1 , Q2 , and L2 .
Mode 2 [t1 –t2 ]: Mode 2 starts when Q2 is turned off at t1 .Then, iL 1 flows through Q1 , CB , and L1 and iL 2
freewheels through D2 . The operation during this mode is the same with mode 1 in the case of D ≤ 0.5.
Mode 3 [t2 –t3 ]: Mode 3 begins when Q2 is turned on at t2 ,and the operation is the same with mode 1.
Mode 4 [t3 –t4 ]: Mode 4 begins when Q1 is turned off at t3 . Then, iL 1 freewheels through D1 and iL 2
flows through D1 , CB , Q2 , and L2 . Thus, VCB is discharged. The operation during this mode is the same with
mode 3 in the case of D ≤0.5. The switching states and voltage across different components during different
modes are given in table 2
The operation of the proposed IBC under steady-state operating with D > 0.5 is described. During this
operating condition, the voltage stress of Q1 and D1 is determined by the capacitor voltage VCB, but the voltage
stress of Q2 and D2 is determined by the input voltage. In addition, since VL2 is much larger than VL1 during
mode1 or mode 3, the unbalance between iL1 and iL2 occurs. The current of Q1 , iQ1 , is the sum of iL1 and iL2
4. A Novel Interleaved Buck Converter with Closed Loop Control
19
and the current of Q2 , iQ2 , is equal to iL2 in mode 1 or mode 3. Therefore, it can be said that switches Q1 and Q2
experience high current stress in the case of D > 0.5. It can be known that the proposed IBC has advantages in
terms of efficiency and component stress in the case of only D≤0.5. Thus, the proposed IBC is recommended for
the applications where the operating duty cycle is smaller than or equal to 0.5.
(a)Mode 1 or 3
Fig.4.Circuit operations of proposed IBC for D>.5
Table.2. Switching states and voltages during D>.5
Mode Q1 Q2 VQ1 VQ2 VL1 VL2 VD1 VD2
Mode1 ON ON 0 0 VS-VCB-VO VS-VO VS-VCB VS
Mode2 ON OFF 0 VS VS-VCB-VO -VO VS-VCB 0
Mode3 ON ON 0 0 VS-VCB-VO VS-VO VS-VCB VS
Mode4 OFF ON VS-VCB 0 -VO VCB-VO 0 VCB
III. CLOSED LOOP CONTROL OF THE PROPOSED CONVERTER
A. Control Principles
A dc-dc converter should provide a regulated output voltage under varying load and input voltage
conditions. The component values of converter are also changing with time, temperature, pressure etc. So the
control of the output voltage should be performed in a closed-loop manner using principles of negative
feedback.
Fig.5.Voltage mode closed loop control
One of the closed loop control method of PWM dc-dc converters is voltage mode control. In the
voltage-mode control as shown in Fig.5 the converter output voltage is sensed and subtracted from an external
reference voltage in an error amplifier. The error amplifier produces a control voltage that is compared to a
constant- amplitude saw-tooth waveform. The comparator produces a PWM signal that is fed to drivers of
controllable switches in the dc-dc converter. The duty ratio of the PWM signal depends on the value of the
control voltage. The frequency of the PWM signal is the same as the frequency of the saw-tooth waveform.[2]
5. A Novel Interleaved Buck Converter with Closed Loop Control
20
B. Proportional Integral Controller
PI Controller (proportional-integral controller) is a feedback controller. It produces an output signal
consisting two terms. One is proportional to the error signal and the second is proportional to the integral of
error signal. The proportional action increases loop gain and integral action reduces steady state error.
Fig.6. SIMULINK model of proposed interleaved buck converter with closed loop control
IV. SIMULATION RESULTS
Input voltage given to the converter is 200 v and the switching frequency is50 Khz. It is assumed that
operating duty ratio is less than 50%.It is investigated that due to the improved voltage waveforms in the
proposed IBC, the capacitive discharging and switching losses are reduced. It can be seen that at higher
switching frequency, the increased losses in the proposed IBC are much smaller than that of conventional IBC.
It means that the proposed converter can operate at higher switching frequencies without a significant increase
in the losses. So, it can be said that the propose IBC is more advantageous in terms of efficiency and power
density compared with the conventional IBC. The simulation waveforms using MATLAB are given below.
(a) (b)
(c) (d)
(e)
Fig.7.(a)Voltage across Q1 (b)Voltage across Q2 (c)Voltage acrossD2 (d)Voltage across D1 (e) Output
voltage of proposed converter with closed loop control for D<.5
6. A Novel Interleaved Buck Converter with Closed Loop Control
21
Using the principle of inductor volt second balance , voltage conversion ratio of both conventional and
proposed IBC can be calculated[4]. The relevant analysis results are tabulated in table.3.
Table.3.Analysis results
Items Conventional IBC Proposed IBC
DC conversion ratio D .5D for D<.5 &D2
for D>.5
Voltage stress of Q1 VS .5VS
Voltage stress of Q2 VS VS
Voltage stress of D1 & D2 VS .5VS
THD of proposed converter without feedback control=56%.THD of proposed converter with feedback
control=40%.Using closed loop control the harmonic distortion in output voltage is reduced by 15%.So with a
closed loop control better output voltage is obtained.
V. CONCLUSION
The proposed IBC is suitable for the applications where the duty ratio is less than 50% since for the
proposed IBC, the voltage stress across active switches is half of the input voltage, when duty ratio is less than
50%.It leads to a significant reduction in capacitive discharging and switching losses. Also voltage stress of
freewheeling diode is half of the input voltage. So by employing schottky diodes which have low breakdown
voltage, the reverse recovery and conduction losses on freewheeling diode can be improved. The efficiency of
proposed IBC can be increased by increasing the switching frequency. Closed loop control provides a good
regulated output voltage and also reduces the harmonics in output.THD in the output voltage of a conventional
IBC is 56%.With closed loop THD, in the output voltage is decreased by 15%.
REFERENCES
[1]. Shin Young Cho ,Gun Woo Moon,‖ Interleaved Buck Converter Having Low Switching losses and
Improved Step-Down conversion ratio.
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