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
medium voltage. A fuzzy logic control is used to produce the gate pulses for control circuit of DVR and the
circuit is simulated by using MATLAB/SIMULINK software.
This paper gives a systematic technique of the design and simulation of Dynamic Voltage Restorer (DVR) the use of Sinusoidal Pulse Width Modulation (SPWM). though electricity great associated problems like voltage sags/swells arise both at the transmission aspect as well as the distribution facet, the terminology used for the compensation devices is exclusive. DVR is a series linked tool used for compensating voltage sags and swells at the distribution side. on this work, a step by step technique is given to determine out the additives which can be required for the layout and simulation of DVR. The detection of sags/swells is completed with the assist of d-q-o concept, whereas the manager of the voltage source inverter is achieved with the assist of SPWM. The VSI has been applied with the assist of both Bipolar SPWM in addition to Unipolar SPWM and the results were compared. The simulation becomes achieved with the help of SIMULINK & MATLAB and the consequences have been located to be in accordance with concept.
this is useful for peoples interested in power quality problems and their mitigation. it provides causes, effects of voltage sag and their mitigation techniques.
Power Quality Enhancement through Dynamic Voltage Restorer using SRF Theory f...IJERD Editor
Power quality is certainly a major concern in the present era, it becomes especially important with
the introduction of sophisticated devices, whose performance is very sensitive to the quality of power supply.
Voltage sag is one of the severe power quality problems. This report addresses all the different aspects related to
voltage sag problem, such as its types, consequences and mitigation.
At present, a wide range of very flexible controllers, which capitalize on newly available power electronics
components, are emerging for custom power applications. Among these, the distribution static compensator (DSTATCOM)
and the dynamic voltage restorer (DVR) are most effective devices, both of them based on the
VSC principle.
Mitigation of Voltage Sag/Swell using Custom Power Devices with SMES System i...Editor IJMTER
Any power problem noticed in voltage, current or frequency deviations that results in
misoperation of customer or end user equipment. The new method of dynamic voltage restorer with
SMES is proposed to protect consumers load from tripping .The DVR can effectively inject the
voltage to the power lines. To improve the performance of DVR the superconducting magnet is
selected as the energy storage unit. The compensation of the voltage sag, swell by short period of
voltage injection. SMES based DVR has been used to improve the performance of power system. It
is having high power rating with maximum efficiency than any other energy storage devices. It
restores line voltage to its nominal value within few milliseconds. Most of the power quality
problems are voltage sag, swell, interruption, transient, fluctuation, etc.. Among those power quality
problem voltage sag is severe one. So it is analyzing and mitigated using custom power device and
SMES system using MATLAB SIMULINK in proposed system.
This paper gives a systematic technique of the design and simulation of Dynamic Voltage Restorer (DVR) the use of Sinusoidal Pulse Width Modulation (SPWM). though electricity great associated problems like voltage sags/swells arise both at the transmission aspect as well as the distribution facet, the terminology used for the compensation devices is exclusive. DVR is a series linked tool used for compensating voltage sags and swells at the distribution side. on this work, a step by step technique is given to determine out the additives which can be required for the layout and simulation of DVR. The detection of sags/swells is completed with the assist of d-q-o concept, whereas the manager of the voltage source inverter is achieved with the assist of SPWM. The VSI has been applied with the assist of both Bipolar SPWM in addition to Unipolar SPWM and the results were compared. The simulation becomes achieved with the help of SIMULINK & MATLAB and the consequences have been located to be in accordance with concept.
this is useful for peoples interested in power quality problems and their mitigation. it provides causes, effects of voltage sag and their mitigation techniques.
Power Quality Enhancement through Dynamic Voltage Restorer using SRF Theory f...IJERD Editor
Power quality is certainly a major concern in the present era, it becomes especially important with
the introduction of sophisticated devices, whose performance is very sensitive to the quality of power supply.
Voltage sag is one of the severe power quality problems. This report addresses all the different aspects related to
voltage sag problem, such as its types, consequences and mitigation.
At present, a wide range of very flexible controllers, which capitalize on newly available power electronics
components, are emerging for custom power applications. Among these, the distribution static compensator (DSTATCOM)
and the dynamic voltage restorer (DVR) are most effective devices, both of them based on the
VSC principle.
Mitigation of Voltage Sag/Swell using Custom Power Devices with SMES System i...Editor IJMTER
Any power problem noticed in voltage, current or frequency deviations that results in
misoperation of customer or end user equipment. The new method of dynamic voltage restorer with
SMES is proposed to protect consumers load from tripping .The DVR can effectively inject the
voltage to the power lines. To improve the performance of DVR the superconducting magnet is
selected as the energy storage unit. The compensation of the voltage sag, swell by short period of
voltage injection. SMES based DVR has been used to improve the performance of power system. It
is having high power rating with maximum efficiency than any other energy storage devices. It
restores line voltage to its nominal value within few milliseconds. Most of the power quality
problems are voltage sag, swell, interruption, transient, fluctuation, etc.. Among those power quality
problem voltage sag is severe one. So it is analyzing and mitigated using custom power device and
SMES system using MATLAB SIMULINK in proposed system.
—In this paper, different voltage injection schemes for
dynamic voltage restorers (DVRs) are analyzed with particular
focus on a new method used to minimize the rating of the voltage
source converter (VSC) used in DVR. A new control technique is
proposed to control the capacitor-supported DVR. The control of
a DVR is demonstrated with a reduced-rating VSC. The reference
load voltage is estimated using the unit vectors. The synchronous
reference frame theory is used for the conversion of voltages from
rotating vectors to the stationary frame. The compensation of
the voltage sag, swell, and harmonics is demonstrated using a
reduced-rating DVR.
In this paper, different voltage injection schemes for dynamic voltage restorers (DVRs) are analyzed with particular focus on a new method used to minimize the rating of the voltage source converter (VSC) used in DVR. A new control technique is proposed to control the capacitor-supported DVR. The control of a DVR is demonstrated with a reduced-rating VSC. The reference load voltage is estimated using the unit vectors. The synchronous reference frame theory is used for the conversion of voltages from rotating vectors to the stationary frame. The compensation of the voltage sag, swell, and harmonics is demonstrated using a reduced-rating DVR.
Power quality problems such as transients, sags, swells, and other distortions to the sinusoidal waveform of the supply voltage affect the performance of these equipment pieces. Technologies such as custom power devices are emerged to provide protection against power quality problems. Custom power devices are mainly of three categories such as series-connected compensators known as dynamic voltage restorers (DVRs), shunt-connected compensators such as distribution static compensators, and a combination of series and shunt-connected compensators known as unified power quality conditioner. The DVR can regulate the load voltage from the problems such as sag, swell, and harmonics in the supply voltages. Hence, it can protect the critical consumer loads from tripping and consequent losses . The custom power devices are developed and installed at consumer point to meet the power quality standards such as IEEE-519 .
Voltage sags in an electrical grid are not always possible to avoid because of the finite clearing time of the faults that cause the voltage sags and the propagation of sags from the
Transmission and distribution systems to the low-voltage loads. Voltage sags are the common reasons for interruption in production plants and for end-user equipment malfunctions in general. In particular, tripping of equipment in a production line can cause production interruption and significant costs due to loss of production. One solution to this problem is to make the equipment itself more tolerant to sags, either by intelligent control or by storing “ride-through” energy in the equipment. An alternative solution, instead of modifying each component in a plant to be tolerant against voltage sags, is to install a plant wide uninterruptible power supply system for longer power interruptions or a DVR on the incoming supply to mitigate voltage sags for shorter periods [8]–[23]. DVRs can eliminate most of the sags and minimize the risk of load tripping for very deep sags, but their main drawbacks are their standby losses, the equipment cost, and also the protection
Scheme required for downstream short circuits.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
Power Quality Improvement Using A DVR (Dynamic Voltage Restorer)
ABSTRACT
Power quality is one of major problems in the today’s scenario. It has become important with the introduction of complex devices, whose performance is very sensitive to the quality of power supply. Power quality problem is an occurrence developed as a nonstandard voltage, current or frequency that results in a failure of end use equipment. Some of the major problems dealt here is the power sag and swell. This paper describes the effectiveness of using dynamic voltage restorer (DVR) in order to mitigate voltage sags and swells in low voltage distribution systems. Dynamic Voltage Restorer can provide the most cost effective solution to mitigate voltage sags and swells that is required by customer. The Dynamic Voltage Restorer (DVR) is a rapid, flexible and resourceful solution to power quality problems.
POWER QUALITY IMPROVEMENT AND FAULT RIDE THROUGH OF GRID CONNECTED WIND ENE...Bharadwaj S
This work tries to improve the power quality by compensating reactive power with Active Power Filters and also to analyze Fault Ride Through of Grid connected wind energy conversion systems.
Control of Dvr with Battery Energy Storage System Using Srf TheoryIJERA Editor
One of the best solutions to improve power quality is the dynamic voltage restorer (DVR). DVR is a kind of
custom power devices that can inject active/reactive power to the power grids. This can protect loads from
disturbances such as sag and swell. Usually DVR installed between sensitive loads feeder and source in
distribution system. Its features include lower cost, smaller size, and its fast dynamic response to the
disturbance. In this project SRF technique is used for conversion of voltage from rotating vectors to the
stationary frame. SRF technique is also referred as park’s transformation. In this the reference load voltage is
estimated using the unit vectors. The real power exchanged at the DVR output ac terminal is provided by the
DVR input dc terminal by an external energy source or energy storage system. In this project three phase
parallel or series load may be used along with SRF technique to compensate voltage sag and voltage swell. And
also wind generator is also used as a load. This project presents the simulation of DVR system using
MATLAB/SIMULINK.
Enhancement of Power Quality Problem by Using Dynamic Voltage RestorerAM Publications
Dynamic voltage restorers (DVRs) are used to protect sensitive loads from the effects of voltage sags on the
distribution feeder. This paper presents and verifies a novel voltage sag detection technique for use in conjunction
with the main control system of a DVR. In all cases it is necessary for the DVR control system to not only detect the
start and end of a voltage sag but also to determine the sag depth and any associated phase shift. The DVR, which is
placed in series with a sensitive load, must be able to respond quickly to a voltage sag if end users of sensitive
equipment are to experience no voltage sag. The DVR can restore the load voltage within few milliseconds. A control
technique based on a proportional–integral (PI) controller and a selective controller is used. The controller is
designed in a synchronously-rotating reference frame. In fact, three independent controllers have been used to tackle
balanced and unbalanced voltage supplies. Simulation results using ‘MATLAB SIMULINK’ Sim Power System
Toolbox is presented to illustrate the principle and performance of a DVR operation in load voltage compensation.
Sag mitigation in distribution system by using Dynamic voltage Restorer (DVR)IJERA Editor
Power quality is most important concern in the current age. It’s now a day’s necessary with the refined devices, where performance is very perceptive to the quality of power supply. Power quality crisis is an incidence manifest as a typical voltage, current or frequency that results in a failure of end use equipments. One of the major crises dealt here is the power sag. Perceptive industrial loads and distribution networks suffer from different types of service interruptions and outages which results in a major financial loss. To improve the power quality, custom power-devices are used. The device considered in this work is Dynamic Voltage Restorer. This paper shows modelling, analysis and simulation of a DVR test systems using MATLAB.
I have considered single line to ground fault for linear load. The role of DVR is to “compensate load voltage” is examined during the different fault conditions like voltage sag, single phase to ground faults.
LOW VOLTAGE RIDE - THROUGH CAPABILITY OF WIND FARMSEditor IJMTER
Nowadays wind turbines are generally required to offer ancillary services similar to those
provided by conventional generators. One of the most important services wind turbines must offer is
to stay connected to the grid in fault situations delivering the reactive current specified in the recent
grid codes. In this paper, FACTS solutions for fixed speed wind farms such as DVR (Dynamic
Voltage Restorer) are presented as well as classic control and crowbar solutions for variable speed
wind turbines.
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.
A Review of Matrix Converter and Novel Control Method of DC-AC Matrix Converteridescitation
For the past three decades, research work in matrix
converter has increased much. This paper presents a new
topology of DC-AC matrix converter, starting with a brief
historical review of different modulation and control strategies
which was developed recently. The purpose of the Paper is to
generate a multilevel output voltage equal to multilevel
inverter with reduced switches. An important part of the paper
is to design a dedicated DC-AC matrix converter and some
new arrays of bidirectional switches in a single module are
also presented. To find the performance of the module the
entire module is designed with MATLAB simulation and tested
with three phase induction motor.
DVR with Artificial Intelligent Controller for Voltage Sag MitigationMohamed Khaleeel
This paper concludes that DVR is an effective device to compensate the voltage sag in power distribution systems. In term of DVR applications, although Mamdani-type and Sugeno-type share the same functions and rules, there are some distinctions between them.
—In this paper, different voltage injection schemes for
dynamic voltage restorers (DVRs) are analyzed with particular
focus on a new method used to minimize the rating of the voltage
source converter (VSC) used in DVR. A new control technique is
proposed to control the capacitor-supported DVR. The control of
a DVR is demonstrated with a reduced-rating VSC. The reference
load voltage is estimated using the unit vectors. The synchronous
reference frame theory is used for the conversion of voltages from
rotating vectors to the stationary frame. The compensation of
the voltage sag, swell, and harmonics is demonstrated using a
reduced-rating DVR.
In this paper, different voltage injection schemes for dynamic voltage restorers (DVRs) are analyzed with particular focus on a new method used to minimize the rating of the voltage source converter (VSC) used in DVR. A new control technique is proposed to control the capacitor-supported DVR. The control of a DVR is demonstrated with a reduced-rating VSC. The reference load voltage is estimated using the unit vectors. The synchronous reference frame theory is used for the conversion of voltages from rotating vectors to the stationary frame. The compensation of the voltage sag, swell, and harmonics is demonstrated using a reduced-rating DVR.
Power quality problems such as transients, sags, swells, and other distortions to the sinusoidal waveform of the supply voltage affect the performance of these equipment pieces. Technologies such as custom power devices are emerged to provide protection against power quality problems. Custom power devices are mainly of three categories such as series-connected compensators known as dynamic voltage restorers (DVRs), shunt-connected compensators such as distribution static compensators, and a combination of series and shunt-connected compensators known as unified power quality conditioner. The DVR can regulate the load voltage from the problems such as sag, swell, and harmonics in the supply voltages. Hence, it can protect the critical consumer loads from tripping and consequent losses . The custom power devices are developed and installed at consumer point to meet the power quality standards such as IEEE-519 .
Voltage sags in an electrical grid are not always possible to avoid because of the finite clearing time of the faults that cause the voltage sags and the propagation of sags from the
Transmission and distribution systems to the low-voltage loads. Voltage sags are the common reasons for interruption in production plants and for end-user equipment malfunctions in general. In particular, tripping of equipment in a production line can cause production interruption and significant costs due to loss of production. One solution to this problem is to make the equipment itself more tolerant to sags, either by intelligent control or by storing “ride-through” energy in the equipment. An alternative solution, instead of modifying each component in a plant to be tolerant against voltage sags, is to install a plant wide uninterruptible power supply system for longer power interruptions or a DVR on the incoming supply to mitigate voltage sags for shorter periods [8]–[23]. DVRs can eliminate most of the sags and minimize the risk of load tripping for very deep sags, but their main drawbacks are their standby losses, the equipment cost, and also the protection
Scheme required for downstream short circuits.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
Power Quality Improvement Using A DVR (Dynamic Voltage Restorer)
ABSTRACT
Power quality is one of major problems in the today’s scenario. It has become important with the introduction of complex devices, whose performance is very sensitive to the quality of power supply. Power quality problem is an occurrence developed as a nonstandard voltage, current or frequency that results in a failure of end use equipment. Some of the major problems dealt here is the power sag and swell. This paper describes the effectiveness of using dynamic voltage restorer (DVR) in order to mitigate voltage sags and swells in low voltage distribution systems. Dynamic Voltage Restorer can provide the most cost effective solution to mitigate voltage sags and swells that is required by customer. The Dynamic Voltage Restorer (DVR) is a rapid, flexible and resourceful solution to power quality problems.
POWER QUALITY IMPROVEMENT AND FAULT RIDE THROUGH OF GRID CONNECTED WIND ENE...Bharadwaj S
This work tries to improve the power quality by compensating reactive power with Active Power Filters and also to analyze Fault Ride Through of Grid connected wind energy conversion systems.
Control of Dvr with Battery Energy Storage System Using Srf TheoryIJERA Editor
One of the best solutions to improve power quality is the dynamic voltage restorer (DVR). DVR is a kind of
custom power devices that can inject active/reactive power to the power grids. This can protect loads from
disturbances such as sag and swell. Usually DVR installed between sensitive loads feeder and source in
distribution system. Its features include lower cost, smaller size, and its fast dynamic response to the
disturbance. In this project SRF technique is used for conversion of voltage from rotating vectors to the
stationary frame. SRF technique is also referred as park’s transformation. In this the reference load voltage is
estimated using the unit vectors. The real power exchanged at the DVR output ac terminal is provided by the
DVR input dc terminal by an external energy source or energy storage system. In this project three phase
parallel or series load may be used along with SRF technique to compensate voltage sag and voltage swell. And
also wind generator is also used as a load. This project presents the simulation of DVR system using
MATLAB/SIMULINK.
Enhancement of Power Quality Problem by Using Dynamic Voltage RestorerAM Publications
Dynamic voltage restorers (DVRs) are used to protect sensitive loads from the effects of voltage sags on the
distribution feeder. This paper presents and verifies a novel voltage sag detection technique for use in conjunction
with the main control system of a DVR. In all cases it is necessary for the DVR control system to not only detect the
start and end of a voltage sag but also to determine the sag depth and any associated phase shift. The DVR, which is
placed in series with a sensitive load, must be able to respond quickly to a voltage sag if end users of sensitive
equipment are to experience no voltage sag. The DVR can restore the load voltage within few milliseconds. A control
technique based on a proportional–integral (PI) controller and a selective controller is used. The controller is
designed in a synchronously-rotating reference frame. In fact, three independent controllers have been used to tackle
balanced and unbalanced voltage supplies. Simulation results using ‘MATLAB SIMULINK’ Sim Power System
Toolbox is presented to illustrate the principle and performance of a DVR operation in load voltage compensation.
Sag mitigation in distribution system by using Dynamic voltage Restorer (DVR)IJERA Editor
Power quality is most important concern in the current age. It’s now a day’s necessary with the refined devices, where performance is very perceptive to the quality of power supply. Power quality crisis is an incidence manifest as a typical voltage, current or frequency that results in a failure of end use equipments. One of the major crises dealt here is the power sag. Perceptive industrial loads and distribution networks suffer from different types of service interruptions and outages which results in a major financial loss. To improve the power quality, custom power-devices are used. The device considered in this work is Dynamic Voltage Restorer. This paper shows modelling, analysis and simulation of a DVR test systems using MATLAB.
I have considered single line to ground fault for linear load. The role of DVR is to “compensate load voltage” is examined during the different fault conditions like voltage sag, single phase to ground faults.
LOW VOLTAGE RIDE - THROUGH CAPABILITY OF WIND FARMSEditor IJMTER
Nowadays wind turbines are generally required to offer ancillary services similar to those
provided by conventional generators. One of the most important services wind turbines must offer is
to stay connected to the grid in fault situations delivering the reactive current specified in the recent
grid codes. In this paper, FACTS solutions for fixed speed wind farms such as DVR (Dynamic
Voltage Restorer) are presented as well as classic control and crowbar solutions for variable speed
wind turbines.
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.
A Review of Matrix Converter and Novel Control Method of DC-AC Matrix Converteridescitation
For the past three decades, research work in matrix
converter has increased much. This paper presents a new
topology of DC-AC matrix converter, starting with a brief
historical review of different modulation and control strategies
which was developed recently. The purpose of the Paper is to
generate a multilevel output voltage equal to multilevel
inverter with reduced switches. An important part of the paper
is to design a dedicated DC-AC matrix converter and some
new arrays of bidirectional switches in a single module are
also presented. To find the performance of the module the
entire module is designed with MATLAB simulation and tested
with three phase induction motor.
DVR with Artificial Intelligent Controller for Voltage Sag MitigationMohamed Khaleeel
This paper concludes that DVR is an effective device to compensate the voltage sag in power distribution systems. In term of DVR applications, although Mamdani-type and Sugeno-type share the same functions and rules, there are some distinctions between them.
Characteristics Analysis of Voltage Sag in Distribution System using RMS Volt...IDES Editor
Voltage sags caused by the short-circuit faults in
transmission and distribution lines have become one of the
most important power quality problems facing industrial
customers and utilities. Voltage sags are normally described
by characteristics of both magnitude and duration, but phaseangle
jump should be taken into account in identifying sag
phenomena and finding their solutions. In this paper, voltage
sags due to power system faults such as three-phase-to-ground,
single phase-to-ground, phase-to-phase, and two-phase-toground
faults are characterized by using symmetrical
component analysis and their effect on the magnitude
variation and phase-angle jumps for each phase are examined.
A simple and practical method is proposed for voltage sag
detection, by calculating RMS voltage over a window of one
cycle and one-half cycle. The industrial distribution system
at Bajaj hospital is taken as a case study. Simulation studies
have been performed by suing MATLAB/SIMULINK and the
results are presented at various magnitudes, duration and
phase-angle jumps.
nternational 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.
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.
Characteristics of Feed grizzly
1.Smooth vibration
2.Reliable operation
3.Long service life
4.Low noise
5.Low power consumption
6.Easy to adjust
7.Simple structure
8.Easy to install
9.Light weight
10.Small volume
11.Simple maintenance
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.
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.
VOLTAGE SAG AND SWELL ALLEVIATION IN DISTRIBUTION NETWORK USING CUSTOM POWER...Gaddafi Sani
IEEE-Pemc 2014 conference: VOLTAGE SAG AND SWELL ALLEVIATION IN DISTRIBUTION NETWORK USING CUSTOM POWER DEVICES; D-STATCOM AND DVR. by Abdullahi Kunya, T. Yalcinoz, Gaddafi Shehu
Design Modification of Failure Mode Effect Analysis of Vibrating Feeder used ...ijsrd.com
Vibratin feeder technology is common in material handling applications in numerous industries. This review paper examines a problem with fatigue in the support structure of a specific type of vibrating feeder. It also reviews the theory behind vibrating feeder technology and considerations that engineers who design them need to be aware of. The finite element method is used to replicate a fatigue problem in the support structure and various design configurations are then analyzed to reduce the risk of the conditions that caused the fatigue. The results are reviewed and recommendations are made to improve the design and modify the component dimensional parameters vibrating feeder.
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.
SIMULATION OF CASCADED H- BRIDGE MULTILEVEL INVERTER USING PD, POD, APOD TECH...ecij
Multilevel inverter (MLI) can achieve medium voltage high power efficiency inverters in industrial
application. It can generate stepped waveform by reducing harmonic distortion with increase in the
number of voltage level; a full bridge is known as H-bridge inverter because it shows alphabet ‘H’. In this
paper, Multicarrier PWM topologies and there Modulation schemes are discussed. Level Shifted [LS]
Scheme is applied to the Cascade H-bridge multilevel inverter and the complete analysis of THD to 9 levels
is done.
Design and Analysis of Adaptive Neural Controller for Voltage Source Converte...IDES Editor
Usually a STATCOM is installed to support power
system networks that have a poor power factor and often poor
voltage regulation. It is based on a power electronics voltagesource
converter. Various PWM techniques make selective
harmonic elimination possible, which effectively control the
harmonic content of voltage source converters. The distribution
systems have to supply unbalanced nonlinear loads transferring
oscillations to the DC-side of the converter in a realistic
operating condition. Thus, additional harmonics are modulated
through the STATCOM at the point of common coupling
(PCC). This requires more attention when switching angles are
calculated offline using the optimal PWM technique. This
paper, therefore, presents the artificial neural network model
for defining the switching criterion of the VSC for the
STATCOM in order to reduce the total harmonic distortion
(THD) of the injected line current at the PCC. The model takes
into the account the dc capacitor effect, effects of other possible
varying parameters such as voltage unbalance as well as
network harmonics. A reference is developed for offline
prediction and then implemented with the help of back
propagation technique.
Analysis of Total Harmonic Distortion (THD) Level of Distribution Network Usi...IJERA Editor
The modern sensitive, Non-linear and sophisticated load affects the power quality. Dynamic Voltage Restorer (DVR) provides the fast, flexible and efficient solution to improve the power quality for such distribution network [8]. The active power, reactive power, variation of voltage, flicker, harmonics, and electrical behavior of switching operations are the major source of affecting power quality. The intent of this paper is to demonstrate the improvements obtained with DVR in power system network using MATLAB/SIMULINK. In this paper, an overview of the DVR, its functions, configurations, components, control strategies are reviewed. The Simulation results are presented to illustrate the performance of DVR in Total Harmonic Distortion (THD). The results showed clearly the performance of using DVR in improving THD level.
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.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
Contemporary Control of DG Integrated DVR for Sag, Swell and Harmonic Mitigat...IJECEIAES
This paper presents a novel control strategy to control DG integrated DVR (dynamic voltage restorer) for mitigation voltage quality problems. Power quality is the most concerning areas in power engineering and voltage quality is of prime focus. Voltage sag, voltage swell and harmonics in voltage causes deterioration in quality of voltage delivered to load. A minor disturbance in voltage profile can degrade the performance of load. Dynamic voltage restorer is a quick responsive custom power device for voltage quality improvement. Photovoltaic (PV) system is considered as DG and output voltage of PV system is boosted with a boost converter to support voltage source converter of DVR. DG integrated DVR with novel control strategy for mitigation of voltage sag, swell and voltage harmonic is presented in this paper. The power system model with DG integrated DVR is developed and results are obtained using MATLAB/SIMULINK. Results are discussed during pre and post sag/swell condition with compensation and THD in voltage is maintained within nominal values.
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.
Compensation of Sag and Swell Voltage by using Dynamic Voltage Restorerijtsrd
The increase use of modern sensitive and sophisticated loads connected to distribution system causes various problems to the system. The major problems are voltage sag and swell, there is need to compensate it .Today most of the distribution companies are using power semiconductor based devices for improving power quality. Among the various custom power devices, Dynamic voltage restorer is used for compensation in this paper, which is most popular and widely used method. Here, in phase compensation technique of DVR is used with battery energy storage system. The DVR's life time is improved by replacing battery with super capacitor. Super capacitor are most suitable short duration energy requirement. The control technique employed here is SRF controller. The overall work is carried out in MATLAB Simulink. Diksha Wasnik | Prof Radharaman Shaha | Pratik Ghutke ""Compensation of Sag and Swell Voltage by using Dynamic Voltage Restorer"" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-4 , June 2019, URL: https://www.ijtsrd.com/papers/ijtsrd23740.pdf
Paper URL: https://www.ijtsrd.com/engineering/electrical-engineering/23740/compensation-of-sag-and-swell-voltage-by-using-dynamic-voltage-restorer/diksha-wasnik
Research Inventy : International Journal of Engineering and Scienceresearchinventy
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.
Dvr Based Power Quality Improvement In Distribution Systeminventionjournals
International Journal of Engineering and Science Invention (IJESI) is an international journal intended for professionals and researchers in all fields of computer science and electronics. IJESI publishes research articles and reviews within the whole field Engineering Science and Technology, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online.
Modeling and simulation of dynamic voltage restorer for voltage sag mitigatio...IJRRR
Abstract- Power quality deals with utilization of electric energy from the distribution system successfully without interference or interruption. Various factors like interruption in power supply, under voltage, over voltage, unbalanced voltage or current, harmonic distortion, flickering voltage, voltage fluctuation voltage sag etc. result in poor power quality. These power quality related problems can be solved with the help of various custom power devices. Voltage sags are considered to be the most common type of disturbances in the field based on current power disturbances studies. Their impact on sensitive loads is rigorous. The impact ranges from load disruptions to financial losses. In spite of the technical advances in electronics, there are some pieces of equipment that are so sensitive that they are unable to withstand voltage sags. There are many varies methods to mitigate voltage sags, but a Custom Power Supply device is considered to be the most efficient method. This dissertation is the study of Dynamic Voltage Restorer (DVR) which is the most efficient and effective device to protect sensitive equipment against voltage sags. It has low cost, smaller size and it has dynamic response to the disturbance.
Keywords- Voltage sag, DVR, power system, mitigation
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.
Study on the Fused Deposition Modelling In Additive ManufacturingIJERD Editor
Additive manufacturing process, also popularly known as 3-D printing, is a process where a product
is created in a succession of layers. It is based on a novel materials incremental manufacturing philosophy.
Unlike conventional manufacturing processes where material is removed from a given work price to derive the
final shape of a product, 3-D printing develops the product from scratch thus obviating the necessity to cut away
materials. This prevents wastage of raw materials. Commonly used raw materials for the process are ABS
plastic, PLA and nylon. Recently the use of gold, bronze and wood has also been implemented. The complexity
factor of this process is 0% as in any object of any shape and size can be manufactured.
Spyware triggering system by particular string valueIJERD Editor
This computer programme can be used for good and bad purpose in hacking or in any general
purpose. We can say it is next step for hacking techniques such as keylogger and spyware. Once in this system if
user or hacker store particular string as a input after that software continually compare typing activity of user
with that stored string and if it is match then launch spyware programme.
A Blind Steganalysis on JPEG Gray Level Image Based on Statistical Features a...IJERD Editor
This paper presents a blind steganalysis technique to effectively attack the JPEG steganographic
schemes i.e. Jsteg, F5, Outguess and DWT Based. The proposed method exploits the correlations between
block-DCTcoefficients from intra-block and inter-block relation and the statistical moments of characteristic
functions of the test image is selected as features. The features are extracted from the BDCT JPEG 2-array.
Support Vector Machine with cross-validation is implemented for the classification.The proposed scheme gives
improved outcome in attacking.
Secure Image Transmission for Cloud Storage System Using Hybrid SchemeIJERD Editor
- Data over the cloud is transferred or transmitted between servers and users. Privacy of that
data is very important as it belongs to personal information. If data get hacked by the hacker, can be
used to defame a person’s social data. Sometimes delay are held during data transmission. i.e. Mobile
communication, bandwidth is low. Hence compression algorithms are proposed for fast and efficient
transmission, encryption is used for security purposes and blurring is used by providing additional
layers of security. These algorithms are hybridized for having a robust and efficient security and
transmission over cloud storage system.
Application of Buckley-Leverett Equation in Modeling the Radius of Invasion i...IJERD Editor
A thorough review of existing literature indicates that the Buckley-Leverett equation only analyzes
waterflood practices directly without any adjustments on real reservoir scenarios. By doing so, quite a number
of errors are introduced into these analyses. Also, for most waterflood scenarios, a radial investigation is more
appropriate than a simplified linear system. This study investigates the adoption of the Buckley-Leverett
equation to estimate the radius invasion of the displacing fluid during waterflooding. The model is also adopted
for a Microbial flood and a comparative analysis is conducted for both waterflooding and microbial flooding.
Results shown from the analysis doesn’t only records a success in determining the radial distance of the leading
edge of water during the flooding process, but also gives a clearer understanding of the applicability of
microbes to enhance oil production through in-situ production of bio-products like bio surfactans, biogenic
gases, bio acids etc.
Gesture Gaming on the World Wide Web Using an Ordinary Web CameraIJERD Editor
- Gesture gaming is a method by which users having a laptop/pc/x-box play games using natural or
bodily gestures. This paper presents a way of playing free flash games on the internet using an ordinary webcam
with the help of open source technologies. Emphasis in human activity recognition is given on the pose
estimation and the consistency in the pose of the player. These are estimated with the help of an ordinary web
camera having different resolutions from VGA to 20mps. Our work involved giving a 10 second documentary to
the user on how to play a particular game using gestures and what are the various kinds of gestures that can be
performed in front of the system. The initial inputs of the RGB values for the gesture component is obtained by
instructing the user to place his component in a red box in about 10 seconds after the short documentary before
the game is finished. Later the system opens the concerned game on the internet on popular flash game sites like
miniclip, games arcade, GameStop etc and loads the game clicking at various places and brings the state to a
place where the user is to perform only gestures to start playing the game. At any point of time the user can call
off the game by hitting the esc key and the program will release all of the controls and return to the desktop. It
was noted that the results obtained using an ordinary webcam matched that of the Kinect and the users could
relive the gaming experience of the free flash games on the net. Therefore effective in game advertising could
also be achieved thus resulting in a disruptive growth to the advertising firms.
Hardware Analysis of Resonant Frequency Converter Using Isolated Circuits And...IJERD Editor
-LLC resonant frequency converter is basically a combo of series as well as parallel resonant ckt. For
LCC resonant converter it is associated with a disadvantage that, though it has two resonant frequencies, the
lower resonant frequency is in ZCS region[5]. For this application, we are not able to design the converter
working at this resonant frequency. LLC resonant converter existed for a very long time but because of
unknown characteristic of this converter it was used as a series resonant converter with basically a passive
(resistive) load. . Here, it was designed to operate in switching frequency higher than resonant frequency of the
series resonant tank of Lr and Cr converter acts very similar to Series Resonant Converter. The benefit of LLC
resonant converter is narrow switching frequency range with light load[6] . Basically, the control ckt plays a
very imp. role and hence 555 Timer used here provides a perfect square wave as the control ckt provides no
slew rate which makes the square wave really strong and impenetrable. The dead band circuit provides the
exclusive dead band in micro seconds so as to avoid the simultaneous firing of two pairs of IGBT’s where one
pair switches off and the other on for a slightest period of time. Hence, the isolator ckt here is associated with
each and every ckt used because it acts as a driver and an isolation to each of the IGBT is provided with one
exclusive transformer supply[3]. The IGBT’s are fired using the appropriate signal using the previous boards
and hence at last a high frequency rectifier ckt with a filtering capacitor is used to get an exact dc
waveform .The basic goal of this particular analysis is to observe the wave forms and characteristics of
converters with differently positioned passive elements in the form of tank circuits.
Simulated Analysis of Resonant Frequency Converter Using Different Tank Circu...IJERD Editor
LLC resonant frequency converter is basically a combo of series as well as parallel resonant ckt. For
LCC resonant converter it is associated with a disadvantage that, though it has two resonant frequencies, the
lower resonant frequency is in ZCS region [5]. For this application, we are not able to design the converter
working at this resonant frequency. LLC resonant converter existed for a very long time but because of
unknown characteristic of this converter it was used as a series resonant converter with basically a passive
(resistive) load. . Here, it was designed to operate in switching frequency higher than resonant frequency of the
series resonant tank of Lr and Cr converter acts very similar to Series Resonant Converter. The benefit of LLC
resonant converter is narrow switching frequency range with light load[6] . Basically, the control ckt plays a
very imp. role and hence 555 Timer used here provides a perfect square wave as the control ckt provides no
slew rate which makes the square wave really strong and impenetrable. The dead band circuit provides the
exclusive dead band in micro seconds so as to avoid the simultaneous firing of two pairs of IGBT’s where one
pair switches off and the other on for a slightest period of time. Hence, the isolator ckt here is associated with
each and every ckt used because it acts as a driver and an isolation to each of the IGBT is provided with one
exclusive transformer supply[3]. The IGBT’s are fired using the appropriate signal using the previous boards
and hence at last a high frequency rectifier ckt with a filtering capacitor is used to get an exact dc
waveform .The basic goal of this particular analysis is to observe the wave forms and characteristics of
converters with differently positioned passive elements in the form of tank circuits. The supported simulation
is done through PSIM 6.0 software tool
Amateurs Radio operator, also known as HAM communicates with other HAMs through Radio
waves. Wireless communication in which Moon is used as natural satellite is called Moon-bounce or EME
(Earth -Moon-Earth) technique. Long distance communication (DXing) using Very High Frequency (VHF)
operated amateur HAM radio was difficult. Even with the modest setup having good transceiver, power
amplifier and high gain antenna with high directivity, VHF DXing is possible. Generally 2X11 YAGI antenna
along with rotor to set horizontal and vertical angle is used. Moon tracking software gives exact location,
visibility of Moon at both the stations and other vital data to acquire real time position of moon.
“MS-Extractor: An Innovative Approach to Extract Microsatellites on „Y‟ Chrom...IJERD Editor
Simple Sequence Repeats (SSR), also known as Microsatellites, have been extensively used as
molecular markers due to their abundance and high degree of polymorphism. The nucleotide sequences of
polymorphic forms of the same gene should be 99.9% identical. So, Microsatellites extraction from the Gene is
crucial. However, Microsatellites repeat count is compared, if they differ largely, he has some disorder. The Y
chromosome likely contains 50 to 60 genes that provide instructions for making proteins. Because only males
have the Y chromosome, the genes on this chromosome tend to be involved in male sex determination and
development. Several Microsatellite Extractors exist and they fail to extract microsatellites on large data sets of
giga bytes and tera bytes in size. The proposed tool “MS-Extractor: An Innovative Approach to extract
Microsatellites on „Y‟ Chromosome” can extract both Perfect as well as Imperfect Microsatellites from large
data sets of human genome „Y‟. The proposed system uses string matching with sliding window approach to
locate Microsatellites and extracts them.
Importance of Measurements in Smart GridIJERD Editor
- The need to get reliable supply, independence from fossil fuels, and capability to provide clean
energy at a fixed and lower cost, the existing power grid structure is transforming into Smart Grid. The
development of a smart energy distribution grid is a current goal of many nations. A Smart Grid should have
new capabilities such as self-healing, high reliability, energy management, and real-time pricing. This new era
of smart future grid will lead to major changes in existing technologies at generation, transmission and
distribution levels. The incorporation of renewable energy resources and distribution generators in the existing
grid will increase the complexity, optimization problems and instability of the system. This will lead to a
paradigm shift in the instrumentation and control requirements for Smart Grids for high quality, stable and
reliable electricity supply of power. The monitoring of the grid system state and stability relies on the
availability of reliable measurement of data. In this paper the measurement areas that highlight new
measurement challenges, development of the Smart Meters and the critical parameters of electric energy to be
monitored for improving the reliability of power systems has been discussed.
Study of Macro level Properties of SCC using GGBS and Lime stone powderIJERD Editor
One of the major environmental concerns is the disposal of the waste materials and utilization of
industrial by products. Lime stone quarries will produce millions of tons waste dust powder every year. Having
considerable high degree of fineness in comparision to cement this material may be utilized as a partial
replacement to cement. For this purpose an experiment is conducted to investigate the possibility of using lime
stone powder in the production of SCC with combined use GGBS and how it affects the fresh and mechanical
properties of SCC. First SCC is made by replacing cement with GGBS in percentages like 10, 20, 30, 40, 50 and
by taking the optimum mix with GGBS lime stone powder is blended to mix in percentages like 5, 10, 15, 20 as
a partial replacement to cement. Test results shows that the SCC mix with combination of 30% GGBS and 15%
limestone powder gives maximum compressive strength and fresh properties are also in the limits prescribed by
the EFNARC.
Seismic Drift Consideration in soft storied RCC buildings: A Critical ReviewIJERD Editor
Reinforced concrete frame buildings are becoming increasingly common in urban India. Many such
buildings constructed in recent times have a special feature – the ground storey is left open for the purpose of
parking, i.e., columns in the ground floor do not have any partition walls (of either masonry or
Reinforced concrete) between them. Such buildings are often called open ground storey buildings. The
relative horizontal displacement in the ground storey is much larger than storeys above it. The total horizontal
earthquake force it can carry in the ground storey is significantly smaller than storeys above it. The soft or weak
storey may exist at any storey level other than ground storey level. The presence of walls in upper storeys
makes them much stiffer than the open ground storey. Still Multi storey reinforced concrete buildings are
continuing to be built in India which has open ground storeys. It is imperative to know the behavior of
soft storey building to the seismic load for designing various retrofit strategies. Hence it is important to
study and understand the response of such buildings and make such buildings earthquake resistant based
on the study to prevent their collapse and to save the loss of life and property.
Post processing of SLM Ti-6Al-4V Alloy in accordance with AMS 4928 standardsIJERD Editor
This Research work was done to find out the impact of AMS 4928 standard heat treatment on
Selective Laser Melted (SLM) Ti-6Al-4V Grade 23 alloy. Ti-6Al-4V Grade 23 is an Extra Low Interstitial
version of Ti alloy with lower impurities and is α+β type alloy at room temperature. SLM is one type of method
in Additive Manufacturing based on Powder bed system. Each powder layer of few microns is coated and a laser
beam is scanned to melt the metal powder according to the specification of the part and subsequently moved
downwards layer by layer. The test coupons were first heat treated according to the above mentioned standard.
The tensile testing and the microstructural analysis were done to compare the results with that of mentioned in
the AMS 4928.The yield stress andPercentage elongation in the test coupons achieved are better than the
minimum requirement by AMS 4928 standard. Coarse lamellar grain structures were obtained with no
continuous network of alpha at prior beta grain boundaries.
Treatment of Waste Water from Organic Fraction Incineration of Municipal Soli...IJERD Editor
Evaporation is one of treatment alternatives of waste water from condensation of vapour in flue gas
or from flue gas scrubber system of an incinerator. The waste water contains tar and heavy metals which are
toxic and must be separated, before discharged to environment or recycled. Due to the relatively low efficiency
of the evaporation process, a combination of the evaporation-absorption process is developed to increase the
efficiency. The aim of this research is to study the separation efficiency of tar from the tar-water mixture from
organic fraction incineration of garbage by evaporation-absorption process, and compared it with the
evaporation process. The evaporation process was performed by evaporating the waste water directly, while the
evaporation-absorption process was carried out by evaporating the waste water before it had been mixed with
palm oil as an absorbent. The results showed that the efficiency to separate the heavy tar of the evaporation
process was 73.27% compared to the combination of evaporation-absorption that was 98.82%. Meanwhile, for
the separation of the light tar, the efficiencies of both process types were almost the same. This system can be
integrated with the incinerator for the treatment of flue gases and waste water generated from the burning of
organic fraction of MSW
Content Based Video Retrieval Using Integrated Feature Extraction and Persona...IJERD Editor
Traditional video retrieval methods fail to meet technical challenges due to large and rapid growth of
multimedia data, demanding effective retrieval systems. In the last decade Content Based Video Retrieval
(CBVR) has become more and more popular. The amount of lecture video data on the Worldwide Web (WWW)
is growing rapidly. Therefore, a more efficient method for video retrieval in WWW or within large lecture video
archives is urgently needed. This paper presents an implementation of automated video indexing and video
search in large videodatabase. First of all, we apply automatic video segmentation and key-frame detection to
extract the frames from video. At next, we extract textual keywords by applying on video i.e. Optical Character
Recognition (OCR) technology on key-frames and Automatic Speech Recognition (ASR) on audio tracks of that
video. At next, we also extractingcolour, texture and edge detector features from different method. At last, we
integrate all the keywords and features which has extracted from above techniques for searching
purpose.Finallysearch similarity measure is applied to retrieve the best matchingcorresponding videos are
presented as output from database. Additionally we are providing Re-ranking of results as per users interest in
original result.
Planar Internal Antenna Design for Cellular Applications & SAR AnalysisIJERD Editor
This paper presents a new design of direct-fed Multi band printed Planar Internal Antenna (PIA), for
cellular applications. The PIA antenna is composed of ground plane, meander radiating strip and two other
parasitic strips are printed on a common substrate. The designed antenna has been simulated in CST
environment. The simulated results for the resonant frequency, return loss, radiation pattern and gain are
presented and discussed. The bandwidths for three resonance achieved on the basis of -6 dB return loss.These
Bandwidths can be utilized for GSM 900, GSM 1800, GSM 1900, LTE 2300 and Bluetooth/WLAN as an
acceptable reference in mobile phones applications. Further the antenna was placed in proximity to the SAR
head on CST environment. The simulated results of SAR analysis are presented in this paper with acceptable
range.
Intelligent learning management system startersIJERD Editor
learning management system (lms) is increasingly gaining popularity in the academic community as
a means of delivering e-learning contents. Simply placing lecture notes and videos among other contents on
lmss do not particularly train the best. This situation could be improved with intelligent tutoring systems (itss)
integration into preferred lms to make it more adaptive and effective, through enhanced student participation
and learning. This work aims, therefore, to create a starter model and a model java its integrated preferred lms.
The its integrated lms starter model was proposed through augmentation and a fluid iterative cycle of
awareness, suggestion, development, evaluation and conclusion. Known open/inexpensive, tried and tested
popular lmss were evaluated at cms matrix site, and complemented. Java its integrated moodle (preferred),
employing certain architectural framework of its integrated lms, was created following the spiral model of
software development
Joint State and Parameter Estimation by Extended Kalman Filter (EKF) techniqueIJERD Editor
In order to increase power system stability and reliability during and after disturbances, power grid
global and local controllers must be developed. SCADA system provides steady and low sampling density. To
remove these limitation PMUs are being rapidly adopted worldwide. Dynamic states of power system can be
estimated using EKF. This requires field excitation as input which may not available. As a result, the EKF with
unknown inputs proposed for identifying and estimating the states and the unknown inputs of the synchronous
machine.
Experimental Study of Material Removal Efficiency in EDM Using Various Types ...IJERD Editor
The machining process in electrical discharge machining (EDM) consists of a melting process and a
removal process. A region of the workpiece surface heated by the discharge plasma is melted and a portion of
the melted region is removed from the workpiece body. The rest of the melted region remains on the workpiece
surface and re-solidified as a white layer. In previous research, to evaluate the removal ability, a ratio of the
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Mitigation of Voltage Sag/Swell with Fuzzy Control Reduced Rating DVR
1. International Journal of Engineering Research and Development
e-ISSN: 2278-067X, p-ISSN: 2278-800X, www.ijerd.com
Volume 11, Issue 09 (September 2015), PP.41-52
41
Mitigation of Voltage Sag/Swell with Fuzzy Control
Reduced Rating DVR
J.Janakiram Naik1
, G.madhavi2
1
M.tech student, electrical and electronics engineering, P.V.P.Siddhartha institute of technology, A.P,
India.
2
Assistant professor, electrical and electronics engineering, P.V.P.Siddhartha institute of technology, A.P,
India.
Abstract: - 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
medium voltage. A fuzzy logic control is used to produce the gate pulses for control circuit of DVR and the
circuit is simulated by using MATLAB/SIMULINK software.
Index Terms: - Dynamic voltage restorer (DVR), power quality, unit vector, voltage harmonics, voltage sag,
voltage swell, Hysteresis Voltage Controller.
I. INTRODUCTION
Power quality and reliability in distribution systems have been tracking an increasing interest in
modern times and have become an area of concern for modern industrial and commercial applications.
Introduction of sophisticated manufacturing systems, industrial drives, precision electronic equipments in
modern times demand greater quality and reliability of power supply in distribution networks than ever before.
Power quality problems encompass a wide range of phenomena. Voltage sag/swell, flicker, harmonics
distortion, impulse transients and interruptions are a prominent few. These disturbances are responsible for
problems ranging from malfunctions or errors to plant shut down and loss of manufacturing capability. Voltage
sags/swells can occur more frequently than any other power quality phenomenon. These sags/swells are the
most important power quality problems in the power distribution system [1].
The main problem of this simple controller is the correct choice of the PI gains and the fact that by
using fixed gains, the controller may not provide the required control performance, when there are variations in
the system parameters and operating conditions. Various control strategies have been developed to mitigate the
voltage sag and swell have been proposed for three phase voltage source PWM converters. They can be divided
into two main groups: linear and nonlinear, linear controllers include the ramp-comparison current regulator,
Synchronous PI regulator, state feedback regulator and predictive and dead-beat regulator. The neural network
and Fuzzy Logic (FL) based regulators belong to the non-linear controllers. It appears that the non-linear
controller is more suitable than the linear type since the DVR is truly a nonlinear system. The DVR is a non-
linear device due to the presence of power semiconductor switches in the inverter bridge.
This paper introduces Dynamic Voltage Restorer (DVR) and its operating principle, also presents the
proposed controllers of PI and fuzzy controllers. Then, simulation results using MATLAB/SIMULINK provide
a comparison between the proposed and the conventional PI controllers in terms of performance in voltage
sag/swell compensation at the end, discussions of the results and conclusion are given.
II. DYNAMIC VOLTAGE RESTORER (DVR)
DVR is a Custom Power Device used to eliminate supply side voltage disturbances. DVR also
known as Static Series Compensator maintains the load voltage at a desired magnitude and phase by
compensating the voltage sags/swells and voltage unbalances presented at the point of common coupling.
The power circuit of the DVR is shown in Fig. 1.The DVR consists of 6 major parts:-
2. Mitigation of Voltage Sag/Swell with Fuzzy Control Reduced Rating DVR
42
a) Voltage Source Inverter (VSI): These inverters have low voltage ratings and high current ratings as step up
transformers are used to boost up the injected voltage.
b) Injection Transformers: Three single phase injection transformers are connected in delta/open winding
to the distribution line.
Fig.1: DVR series connected topology
These transformers can be also connected in star/open winding. The star/open winding allows injection of
positive, negative and zero sequence voltages whereas delta/open winding only allows positive and negative
sequence voltage injection.
c) Passive Filters: Passive filters are placed at the high voltage side of the DVR to filter the harmonics. These
filters are placed at the high voltage side as placing the filters at the inverter side introduces phase angle shift
which can disrupt the control algorithm.
d) Energy storage: Batteries, flywheels or SMEs can be used to provide real power for compensation.
Compensation using real power is essential when large voltage sag occurs.
e) Capacitor: DVR has a large DC capacitor to ensure stiff DC voltage input to inverter.
f) By-Pass Switch: If the over current on the load side exceeds a permissible limit due to short circuit on the
load or large inrush current, the DVR will be isolated from the system by using the bypass switches and
supplying another path for current.
III. OPERATION OF DVR
The schematic of a DVR-connected system is shown in Fig. 2(a). The voltage Vinj is inserted such that
the load voltage Vload is constant in magnitude and is undistorted, although the supply voltage Vs is not constant
in magnitude or is distorted. Fig. 2(b) shows the phasor diagram of different voltage injection schemes of the
DVR. VL (pre−sag) is a voltage across the critical load prior to the voltage sag condition. During the voltage sag,
the voltage is reduced toVswith a phase lag angle of θ. Now, the DVR injects a voltage such that the load voltage
magnitude is maintained at the pre-sag condition. According to the phase angle of the load voltage, the injection
of voltages can be realized in four ways [7]. Vinj1 represents the voltage injected in-phase with the supply
voltage. With the injection ofVinj2, the load voltage magnitude remains same but it leads Vs by a small angle. In
Vinj3, the load voltage retains the same phase as that of the pre-sag condition, which may be an optimum angle
considering the energy source. Vinj4 is the condition where the injected voltage is in quadrature with the current,
and this case, is suitable for a capacitor-supported DVR as this injection involves no active power [8]. However,
a minimum possible rating of the converter is achieved byVinj1.
The DVR is operated in this scheme with a battery energy storage system (BESS) [4]. Fig. 3 shows a
schematic of a three-phase DVR connected to restore the voltage of a three-phase critical load. A three-phase
supply is connected to a critical and sensitive load through a three-phase series injection transformer [5]. The
equivalent voltage of the supply of phase A vMa is connected to the point of common coupling (PCC) vSa
through short-circuits impedance Zsa. The voltage injected by the DVR in phase A vCa is such that the load
voltage vLa is of rated magnitude and undistorted. A three-phase DVR is connected to the line to inject a voltage
in series using three single-phase transformers Tr, Lr and Cr represent the filter components used to filter the
ripples in the injected voltage. A three-leg VSC with insulated-gate bipolar transistors (IGBTs) is used as a
DVR, and a BESS is connected to its dc bus.
3. Mitigation of Voltage Sag/Swell with Fuzzy Control Reduced Rating DVR
43
(a) (b)
Fig.2. (a) Basic circuit of DVR. (b) Phasor diagram of the DVR voltage injection schemes.
Fig.3. Schematic of the DVR-connected system
IV. CONTROL OF DVR
The compensation for voltage sags using a DVR can be performed by injecting or absorbing the
reactive power or the real power [8]. When the injected voltage is in quadrature with the current at the
fundamental frequency, the compensation is made by injecting reactive power and the DVR is with a self-
supported dc bus. However, if the injected voltage is in phase with the current, DVR injects real power, and
hence, a battery is required at the dc bus of the VSC. The control technique adopted should consider the
limitations such as the voltage injection capability (converter and transformer rating) and optimization of the
size of energy storage.
A. Control of DVR with BESS for Voltage Sag, Swell, and Harmonics Compensation
Fig. 4 shows a control block of the DVR in which the SRF theory is used for reference signal
estimation. The voltages at the PCC vS and at the load terminal vL are sensed for deriving the IGBTs’ gate
signals. The reference load voltage VL
*
is extracted using the derived unit vector [9]. Load voltages
(VLa,VLb,VLc) are converted to the rotating reference frame using abc−dqo conversion using Park’s
transformation with unit vectors(sin,θ,cos,θ) derived using a phase-locked loop as
(1)
Similarly, reference load voltages and voltages at the PCC vS are also converted to the rotating
reference frame. Then, the DVR voltages are obtained in the rotating reference frame as
(2)
(3)
The reference DVR voltages are obtained in the rotating reference frame as
(4)
(5)
4. Mitigation of Voltage Sag/Swell with Fuzzy Control Reduced Rating DVR
44
The error between the reference and actual DVR voltages in the rotating reference frame is regulated using two
proportional–integral (PI) controllers. Reference DVR voltages in the abc frame are obtained from a reverse
Park’s transformation taking V∗
Dd from (4),V∗
Dq from(5),V∗
D0 as zero as
(6)
Reference DVR voltages and actual DVR voltages are used in
a pulse width modulated (PWM) controller to generate gating pulses to a VSC of the DVR. The PWM
controller is operated with a switching frequency of 10 kHz.
Fig. 4(a).capacitor-supported DVR connected to three-phase critical loads
Fig. 4(b).Control block of the DVR that uses the SRF method of control
B. Control of Self-Supported DVR for Voltage Sag, Swell, and Harmonics Compensation
Fig4 (a).shows a schematic of a capacitor-supported DVR connected to three-phase critical loads, and Fig 4(b)
shows a control block of the DVR in which the SRF theory is use for the control of self-supported DVR.
Voltages at the PCC vs are converted to the rotating reference frame using abc−dqo conversion using Park’s
transformation [6]. The harmonics and the oscillatory components of the voltage are eliminated using low pass
filters (LPFs). The components of voltages in the d- and q-axes are
(7)
(8)
The compensating strategy for compensation of voltage quality problems considers that the load terminal
voltage should be of rated magnitude and undistorted. In order to maintain the dc bus voltage of the self-
supported capacitor, a PI controller is used at the dc bus voltage of the DVR and the output is considered as a
voltage vcap for meeting its losses
The referenced-axis load voltage is therefore expressed as follows:
(9)
The amplitude of load terminal voltage VL is controlled to its reference voltage using another PI controller.
The output of the PI controller is considered as the reactive component of voltage vqr for voltage regulation of
5. Mitigation of Voltage Sag/Swell with Fuzzy Control Reduced Rating DVR
45
the load terminal voltage. The amplitude of load voltage VL at the PCC is calculated from the ac voltages
(vLa,vLb,vLc) as
(10)
The reference load quadrature axis voltage is expressed as follows:
(11)
Reference load voltages ( , ) in the abc frame are obtained from a reverse Park’s transformation as in
(6).
The error between sensed load voltages (vLa, vLb,vLc) and reference load voltages is used over a
controller to generate gating pulses to the VSC of the DVR.
C. About Hysteresis Current Controller
Hysteresis band PWM control is basically an instantaneous feedback current control method of PWM,
where the actual current continuously tracks the command current within a hysteresis band. A reference sine
wave, current wave is compared with the actual phase current wave. When the current exceeds a prescribed
hysteresis band, the upper switch in the inverter bridge is turned off and the lower switch is turned on, and the
current starts to decay. As the current crosses the lower band limit, the lower switch is turned off and the upper
switch is turned on. The actual current is forced to track the sine reference within the hysteresis band by back
and forth (or bang-bang) switching of the upper and lower switches. The inverter then essentially becomes a
current source with peak-to-peak current ripple, which is controlled within the hysteresis band, which makes the
source current to be sinusoidal.
The switching logic is realized by three hysteresis controllers, one for each phase (Fig.5). The
hysteresis PWM current control, also known as ―bang-bang ―control, is done in the three phases separately.
Each controller determines the switching -state of one inverter half-bridge in such a way that the corresponding
current is maintained within a hysteresis band.
Fig.5 Hysteresis PWM Current Control and Switching Logic
To increase a phase current, the affiliated phase to neutral voltage is equal to the half dc bus voltage
until the upper band-range is reached. More complicated hysteresis PWM current control techniques also exist
in practice, e.g. adaptive hysteresis current vector control is based on controlling the current phasor in a α/β -
reference frame. These modified techniques take care especially for the interaction of the three phases.
Obviously, the dynamic performance of such an approach is excellent since the maximum voltage is applied
until the current error is within predetermined boundaries (bang-bang control). Hysteresis current control is
used for operation at higher switching frequency, as this compensates for their inferior quality of modulation.
The switching losses restrict its application to lower power levels. Due to the independence of system
parameters, hysteresis current control is often preferred.
6. Mitigation of Voltage Sag/Swell with Fuzzy Control Reduced Rating DVR
46
V. MATLAB/SIMULINK RESULTS
Here simulation is carried out by several cases, in that 1) Voltage Sag/Swell Compensation by using
Conventional DVR, 2) Voltage Sag/Swell Compensation by using Proposed DVR using PI Controller, 3)
Voltage Sag/Swell Compensation by using Proposed DVR using fuzzy logic control.
Case 1: Voltage Sag/Swell Compensation by using Conventional DVR
The DVR-connected system consisting of a three phase critical loads, and the series injection
transformer is modeled in MATLAB/SIMULINK environment along with a simpower system toolbox. An
equivalent load considered is a 10-KVA 0.8-pf lag linear load. The performance of the DVR is demonstrated for
different supply voltage disturbance such as voltage sag and swell. At 0.2 s a sag in supply voltage is created
and at 0.2 s a swell in supply voltage is created. The phase voltage is 440 volts and phase current is 16.4amp for
this circuit.
Fig.6 shows the MATLAB/SIMULINK Modeling of Conventional DVR under Voltage Sag/Swell Issues using
computer simulation tool. Waveforms are shown in Fig.7.
Fig.6 Matlab/Simulink Modelling of Conventional DVR under Voltage Sag/Swell Issues.
Fig.7.Source Voltage, DVR Injected Voltage, Load Voltage
In Fig.7 first waveform shows the Source Voltage, second waveform shows DVR Injected Voltage and third
waveform shows Load Voltage of the conventional DVR under Voltage Sag Compensation Scheme.
Fig.8.Source Voltage, DVR Injected Voltage, Load Voltage
7. Mitigation of Voltage Sag/Swell with Fuzzy Control Reduced Rating DVR
47
In Fig.8 first waveform shows the Source Voltage, second waveform shows DVR Injected Voltage and
third waveform shows Load Voltage of the conventional DVR under Voltage Sag Compensation Scheme.
Case 2: Voltage Sag/Swell Compensation by using Proposed DVR using PI Controller
The DVR-connected system consisting of a three phase critical loads, and the series injection
transformer is modeled in MATLAB/SIMULINK environment along with a simpower system toolbox. An
equivalent load considered is a 10-KVA 0.8-pf lag linear load. The performance of the DVR is demonstrated for
different supply voltage disturbance such as voltage sag and swell. At 0.2 s a sag in supply voltage is created
and at 0.2 s a swell in supply voltage is created.
The phase voltage is 338.84 v and phase current is 16.4amp for this circuit
Fig.9 Matlab/Simulink Modelling of Proposed DVR under Voltage Sag/Swell Issues
Fig.9 shows the MATLAB/SIMULINK Modeling of Proposed DVR under Voltage Sag/Swell Issues using
computer simulation tool. Waveforms are shown below.
(a) Source Voltage, DVR Injected Voltage, Load Voltage.
(b) RMS value of source voltage, load voltage, Its comparison, DC Link Voltage
8. Mitigation of Voltage Sag/Swell with Fuzzy Control Reduced Rating DVR
48
(c) Source Voltage & Load Voltage
Fig 10(a) source voltage, injected voltage, load voltage, (b) RMS value of source voltage,
load voltage, its comparison, DC link voltage, (c) source voltage & load voltage
In Fig.10 (a) first waveform shows Source Voltage, second waveform shows DVR Injected Voltage and third
waveform shows Load Voltage. In fig.10 (b) first waveform shows the RMS voltage value of source voltage,
second waveform shows the value load voltage, third waveform its comparison, fourth waveform is DC Link
Voltage. In fig 10(c) shows Source Voltage & Load Voltage of the Proposed DVR under Voltage Sag
Compensation Scheme.
(a) Source Voltage, DVR Injected Voltage, Load Voltage.
(b) RMS value of source voltage, load voltage, Its comparison, DC Link Voltage
9. Mitigation of Voltage Sag/Swell with Fuzzy Control Reduced Rating DVR
49
(c) Source Voltage & Load Voltage
Fig 11(a) source voltage, injected voltage, load voltage,
(b) RMS value of source voltage, load voltage, its comparison, DC link voltage,
(c) Source voltage & load voltage
In Fig.11 (a).first waveform shows Source Voltage, second waveform shows DVR Injected Voltage,
third waveform shows Load Voltage, In fig.11 (b) first waveform shows RMS voltage value of source voltage,
second waveform shows load voltage, third waveform shows its comparison, fourth waveform shows DC Link
Voltage and In fig.11(c) shows Source Voltage & Load Voltage of the Proposed DVR under Voltage Swell
Compensation Scheme.
A comparison of the performance of the DVR with different schemes has been performed with a
reduced-rating VSC, including a capacitor-supported DVR.
(a) Source Voltage, DVR Injected Voltage, Load Voltage.
(b) RMS value of source voltage, load voltage, its comparison, DC Link Voltage.
10. Mitigation of Voltage Sag/Swell with Fuzzy Control Reduced Rating DVR
50
(c) THD Analysis of Supply voltage.
Fig 12(a) source voltage, injected voltage, load voltage, (b) RMS value of source voltage, load voltage,
its comparison, DC link voltage, (c) THD analysis of supply voltage
In Fig.12 (a) first waveform shows Source Voltage, second waveform shows DVR Injected Voltage,
third waveform shows Load Voltage. In fig.12 (b) first waveform shows RMS voltage value of source voltage,
second waveform shows load voltage, third waveform shows its comparison, fourth waveform shows DC Link
Voltage. In fig12(c) THD Analysis of Source Voltage of the Proposed DVR under Harmonics Compensation
Scheme. These harmonics are in the range of IEEE-519 standards.
Case 3: Voltage Sag/Swell Compensation by using Proposed DVR using fuzzy logic control.
The DVR-connected system consisting of a three phase critical loads, and the series injection
transformer is modeled in MATLAB/SIMULINK environment along with a simpower system toolbox. An
equivalent load considered is a 10-KVA 0.8-pf lag linear load. The performance of the DVR is demonstrated for
different supply voltages. At 0.2 s a harmonics in supply voltage is created.
Fig.13 shows the MATLAB/SIMULINK Modeling of Proposed DVR under Voltage Sag/Swell Issues
by using fuzzy logic control with the help of computer simulation tool. Waveforms are shown below.
Fig.13 Matlab/Simulink Modeling of Proposed DVR under
Voltage Sag/Swell Issues using fuzzy logic control.
11. Mitigation of Voltage Sag/Swell with Fuzzy Control Reduced Rating DVR
51
(a).Source Voltage, DVR Injected Voltage, Load Voltage.
(b). RMS value of source voltage, load voltage, its comparison, DC Link Voltage.
(c). THD Analysis of Supply voltage
Fig 14(a) source voltage, injected voltage, load voltage, (b) RMS value of source voltage, load voltage,
its comparison, DC link voltage, (c) THD analysis of supply voltage
In Fig.14 (a) first waveform shows Source Voltage, second waveform shows DVR Injected Voltage,
third waveform shows Load Voltage, Source. In fig. (b) first waveform shows RMS voltage value of source
voltage, second waveform shows load voltage, third waveform shows its comparison, DC Link Voltage. In
fig.14(c) THD Analysis of Source Voltage of the Proposed DVR under Harmonics Compensation Scheme with
fuzzy logic controller. These harmonics are in the range of IEEE-519 standards.
12. Mitigation of Voltage Sag/Swell with Fuzzy Control Reduced Rating DVR
52
VI. CONCLUSION
The operation of a DVR has been demonstrated with a new control technique using various voltage
injection schemes. A comparison of the performance of the DVR with different schemes has been performed
with a reduced-rating VSC, including a capacitor-supported DVR. The reference load voltage has been
estimated using the method of unit vectors, and the control of DVR has been achieved, which minimizes the
error of voltage injection. The SRF theory has been used for estimating the reference DVR voltages. It is
concluded that the voltage injection in-phase with the PCC voltage results in minimum rating of DVR but at the
cost of an energy source at its dc bus. The analysis of mitigating harmonics, DVR under fuzzy controller is
carried out using MATLAB Power System Block set. The results of simulation are presented and discussed.
The total harmonic distortion (THD) of voltage at the PCC, supply current, and load voltage. It is observed that
the load voltage THD is reduced to the level of 0.75% from the PCC voltage of 2.50%. The THD and the
amount of unbalance in load voltage are decreased with the application of DVR. The proposed system
performs better than the traditional methods in mitigating harmonics and voltage sags.
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