this is useful for peoples interested in power quality problems and their mitigation. it provides causes, effects of voltage sag and their mitigation techniques.
A power quality presentation includes definitions of power quality, most common power quality problems and the solutions, standard carves, and practical example of an active filter. Presented by - Eng. Shemy Elhady
this is useful for peoples interested in power quality problems and their mitigation. it provides causes, effects of voltage sag and their mitigation techniques.
A power quality presentation includes definitions of power quality, most common power quality problems and the solutions, standard carves, and practical example of an active filter. Presented by - Eng. Shemy Elhady
Introduction: Definition & Reasons of Occurrence of following Voltage Dip, Brief voltage increases, Brief voltage interruption, Transients, Voltage Notches, Flickers, Distortion, Un-balance. Power Quality Indices,Limits of Harmonic Distortion according to IEEE, IEC, EN and NORSOK limits.Brief Introduction of Power quality Standards: IEC 61000-2-5,IEC 61000-2-1, IEC 1159 ( Categories of Power quality variation according to IEEE 1159 standard with their relevant Spectral content, Duration of occurrence & Magnitude)
Hybrid Power System is the integration of number of generating plants those are working together serve a particular region. They may be off grid or may not be.
Power Quality is a combination of Voltage profile, Frequency profile, Harmonics contain and reliability of power supply.
The Power Quality is defined as the degree to which the power supply approaches the ideal case of stable, uninterrupted, zero distortion and disturbance free supply.
Injection of the wind power into an electric grid affects the power quality. The performance of the wind turbine and thereby power quality are determined on the basis of measurements and the norms followed according to the guideline specified in International Electro-technical Commission standard, IEC-61400. The influence of the wind turbine in the grid system concerning the power quality measurements are-the active power, reactive power, variation of voltage, flicker, harmonics, and electrical behavior of switching operation and these are measured according to national/international guidelines. The paper study demonstrates the power quality problem due to installation of wind turbine with the grid. In this proposed scheme STATic COMpensator (STATCOM) is connected at a point of common coupling with a battery energy storage system (BESS) to mitigate the power quality issues. The battery energy storage is integrated to sustain the real power source under fluctuating wind power. The STATCOM control scheme for the grid connected wind energy generation system for power quality improvement is simulated using MATLAB/SIMULINK in power system block set. The effectiveness of the proposed scheme relives the main supply source from the reactive power demand of the load and the induction generator. The development of the grid co-ordination rule and the scheme for improvement in power quality norms as per IEC-standard on the grid has been presented.
with the help of web based power quality monitoring system we can control and manage the data flow of electrical quantity and control the improve the quality of the power system in grid
Long & Short Interruptions: Interruptions – Definition – Difference between failures,
outage, Interruptions – causes of Long Interruptions – Origin of Interruptions – Limits for the
Interruption frequency – Limits for the interruption duration – costs of Interruption –
Overview of Reliability evaluation to power quality, comparison of observations and
reliability evaluation.Short interruptions: definition, origin of short interruptions, basic principle, fuse saving,
voltage magnitude events due to re-closing, voltage during the interruption, monitoring of
short interruptions, difference between medium and low voltage systems. Multiple events,
single phase tripping – voltage and current during fault period, voltage and current at post
fault period
Disadvantages of corona, radio interference, inductive interference between p...vishalgohel12195
Disadvantages of corona, radio interference, inductive interference between power and communication lines
Introduction
Disadvantages of corona.
Radio interference.
Inductive interference between power and communication lines
In microgrid, if fault occurs or any other contingency happens, then the problems would be created which are related to power flow, also there are various protection schemes are used for minimize or eliminate these problems.
Voltage control is used for reactive power balance and P-f control is used for active power control.
Various protection schemes such as, over current protection, differential protection scheme, zoning of network in adaptive protection scheme are used in microgrid system .
Introduction: Definition & Reasons of Occurrence of following Voltage Dip, Brief voltage increases, Brief voltage interruption, Transients, Voltage Notches, Flickers, Distortion, Un-balance. Power Quality Indices,Limits of Harmonic Distortion according to IEEE, IEC, EN and NORSOK limits.Brief Introduction of Power quality Standards: IEC 61000-2-5,IEC 61000-2-1, IEC 1159 ( Categories of Power quality variation according to IEEE 1159 standard with their relevant Spectral content, Duration of occurrence & Magnitude)
Hybrid Power System is the integration of number of generating plants those are working together serve a particular region. They may be off grid or may not be.
Power Quality is a combination of Voltage profile, Frequency profile, Harmonics contain and reliability of power supply.
The Power Quality is defined as the degree to which the power supply approaches the ideal case of stable, uninterrupted, zero distortion and disturbance free supply.
Injection of the wind power into an electric grid affects the power quality. The performance of the wind turbine and thereby power quality are determined on the basis of measurements and the norms followed according to the guideline specified in International Electro-technical Commission standard, IEC-61400. The influence of the wind turbine in the grid system concerning the power quality measurements are-the active power, reactive power, variation of voltage, flicker, harmonics, and electrical behavior of switching operation and these are measured according to national/international guidelines. The paper study demonstrates the power quality problem due to installation of wind turbine with the grid. In this proposed scheme STATic COMpensator (STATCOM) is connected at a point of common coupling with a battery energy storage system (BESS) to mitigate the power quality issues. The battery energy storage is integrated to sustain the real power source under fluctuating wind power. The STATCOM control scheme for the grid connected wind energy generation system for power quality improvement is simulated using MATLAB/SIMULINK in power system block set. The effectiveness of the proposed scheme relives the main supply source from the reactive power demand of the load and the induction generator. The development of the grid co-ordination rule and the scheme for improvement in power quality norms as per IEC-standard on the grid has been presented.
with the help of web based power quality monitoring system we can control and manage the data flow of electrical quantity and control the improve the quality of the power system in grid
Long & Short Interruptions: Interruptions – Definition – Difference between failures,
outage, Interruptions – causes of Long Interruptions – Origin of Interruptions – Limits for the
Interruption frequency – Limits for the interruption duration – costs of Interruption –
Overview of Reliability evaluation to power quality, comparison of observations and
reliability evaluation.Short interruptions: definition, origin of short interruptions, basic principle, fuse saving,
voltage magnitude events due to re-closing, voltage during the interruption, monitoring of
short interruptions, difference between medium and low voltage systems. Multiple events,
single phase tripping – voltage and current during fault period, voltage and current at post
fault period
Disadvantages of corona, radio interference, inductive interference between p...vishalgohel12195
Disadvantages of corona, radio interference, inductive interference between power and communication lines
Introduction
Disadvantages of corona.
Radio interference.
Inductive interference between power and communication lines
In microgrid, if fault occurs or any other contingency happens, then the problems would be created which are related to power flow, also there are various protection schemes are used for minimize or eliminate these problems.
Voltage control is used for reactive power balance and P-f control is used for active power control.
Various protection schemes such as, over current protection, differential protection scheme, zoning of network in adaptive protection scheme are used in microgrid system .
This gives you brief description to electrical power quality problems such as Ttransients, short and long duration voltage variation, voltage unbalance, waveform distortion,voltage fluctuations and power frequency variations.
International Journal of Computational Engineering Research (IJCER)ijceronline
International Journal of Computational Engineering Research(IJCER) is an intentional online Journal in English monthly publishing journal. This Journal publish original research work that contributes significantly to further the scientific knowledge in engineering and Technology.
Design Development and Testing of an Overvoltage and Undervoltage Protection ...Kunal Maity
This voltage protection circuit is designed to develop a low-voltage and high-voltage tripping mechanism to protect a load from any damage. The electronic devices get easily damaged due to fluctuation in AC means supply take place frequently.
Immunizing Image Classifiers Against Localized Adversary Attacksgerogepatton
This paper addresses the vulnerability of deep learning models, particularly convolutional neural networks
(CNN)s, to adversarial attacks and presents a proactive training technique designed to counter them. We
introduce a novel volumization algorithm, which transforms 2D images into 3D volumetric representations.
When combined with 3D convolution and deep curriculum learning optimization (CLO), itsignificantly improves
the immunity of models against localized universal attacks by up to 40%. We evaluate our proposed approach
using contemporary CNN architectures and the modified Canadian Institute for Advanced Research (CIFAR-10
and CIFAR-100) and ImageNet Large Scale Visual Recognition Challenge (ILSVRC12) datasets, showcasing
accuracy improvements over previous techniques. The results indicate that the combination of the volumetric
input and curriculum learning holds significant promise for mitigating adversarial attacks without necessitating
adversary training.
Quality defects in TMT Bars, Possible causes and Potential Solutions.PrashantGoswami42
Maintaining high-quality standards in the production of TMT bars is crucial for ensuring structural integrity in construction. Addressing common defects through careful monitoring, standardized processes, and advanced technology can significantly improve the quality of TMT bars. Continuous training and adherence to quality control measures will also play a pivotal role in minimizing these defects.
Cosmetic shop management system project report.pdfKamal Acharya
Buying new cosmetic products is difficult. It can even be scary for those who have sensitive skin and are prone to skin trouble. The information needed to alleviate this problem is on the back of each product, but it's thought to interpret those ingredient lists unless you have a background in chemistry.
Instead of buying and hoping for the best, we can use data science to help us predict which products may be good fits for us. It includes various function programs to do the above mentioned tasks.
Data file handling has been effectively used in the program.
The automated cosmetic shop management system should deal with the automation of general workflow and administration process of the shop. The main processes of the system focus on customer's request where the system is able to search the most appropriate products and deliver it to the customers. It should help the employees to quickly identify the list of cosmetic product that have reached the minimum quantity and also keep a track of expired date for each cosmetic product. It should help the employees to find the rack number in which the product is placed.It is also Faster and more efficient way.
Vaccine management system project report documentation..pdfKamal Acharya
The Division of Vaccine and Immunization is facing increasing difficulty monitoring vaccines and other commodities distribution once they have been distributed from the national stores. With the introduction of new vaccines, more challenges have been anticipated with this additions posing serious threat to the already over strained vaccine supply chain system in Kenya.
CFD Simulation of By-pass Flow in a HRSG module by R&R Consult.pptxR&R Consult
CFD analysis is incredibly effective at solving mysteries and improving the performance of complex systems!
Here's a great example: At a large natural gas-fired power plant, where they use waste heat to generate steam and energy, they were puzzled that their boiler wasn't producing as much steam as expected.
R&R and Tetra Engineering Group Inc. were asked to solve the issue with reduced steam production.
An inspection had shown that a significant amount of hot flue gas was bypassing the boiler tubes, where the heat was supposed to be transferred.
R&R Consult conducted a CFD analysis, which revealed that 6.3% of the flue gas was bypassing the boiler tubes without transferring heat. The analysis also showed that the flue gas was instead being directed along the sides of the boiler and between the modules that were supposed to capture the heat. This was the cause of the reduced performance.
Based on our results, Tetra Engineering installed covering plates to reduce the bypass flow. This improved the boiler's performance and increased electricity production.
It is always satisfying when we can help solve complex challenges like this. Do your systems also need a check-up or optimization? Give us a call!
Work done in cooperation with James Malloy and David Moelling from Tetra Engineering.
More examples of our work https://www.r-r-consult.dk/en/cases-en/
Final project report on grocery store management system..pdfKamal Acharya
In today’s fast-changing business environment, it’s extremely important to be able to respond to client needs in the most effective and timely manner. If your customers wish to see your business online and have instant access to your products or services.
Online Grocery Store is an e-commerce website, which retails various grocery products. This project allows viewing various products available enables registered users to purchase desired products instantly using Paytm, UPI payment processor (Instant Pay) and also can place order by using Cash on Delivery (Pay Later) option. This project provides an easy access to Administrators and Managers to view orders placed using Pay Later and Instant Pay options.
In order to develop an e-commerce website, a number of Technologies must be studied and understood. These include multi-tiered architecture, server and client-side scripting techniques, implementation technologies, programming language (such as PHP, HTML, CSS, JavaScript) and MySQL relational databases. This is a project with the objective to develop a basic website where a consumer is provided with a shopping cart website and also to know about the technologies used to develop such a website.
This document will discuss each of the underlying technologies to create and implement an e- commerce website.
Student information management system project report ii.pdfKamal Acharya
Our project explains about the student management. This project mainly explains the various actions related to student details. This project shows some ease in adding, editing and deleting the student details. It also provides a less time consuming process for viewing, adding, editing and deleting the marks of the students.
Water scarcity is the lack of fresh water resources to meet the standard water demand. There are two type of water scarcity. One is physical. The other is economic water scarcity.
2. DEFINITION
POWER QUALITY is defined as the ability
of a system or an equipment to function
satisfactorily in its electromagnetic
environment without introducing
intolerable electromagnetic disturbances
to anything in that environment.
PQ mainly deals with
1. Continuity of the supply.
2.”Quality” of the voltage.
3. SCOPE
For economic operation of power systems
Power system design
Future growth
For optimization and reliable operation
To meet the growing needs for standardization
and performance criteria
4. Power Quality Events
Voltage surges
Voltage spikes
Voltage sag
Voltage swell
Voltage fluctuations
&flickering
Voltage unbalance
Harmonic distortion
Noise
Short interruptions
Long interruptions
5. VOLTAGE SURGES
It is a voltage rise that endangers the insulation of
electric equipment.
Causes:
• Shutdown of heavily loaded circuits.
• Switching events such as the connection or disconnection
of a current and short-circuiting to ground.
Effects:
• Computers and other sensitive electronic equipment can
seriously be damaged by such an over-voltage surge.
• Temporal fluctuations produce parity errors and interrupts
protection systems.
6. VOLTAGE SPIKES
In electrical engineering, spikes are fast,
short duration electrical transients in voltage.
Causes:
• Lightning strikes
• Power outages
• Tripped circuit breakers
• Short circuits
Effects:
voltage spikes may be created by a rapid buildup
or decay of a magnetic field, which may be
induced into another circuit
7. VOLTAGE SAG (DIP)
The decrease of nominal voltage level between
10-90 percent of the nominal rms voltage for the
duration of 0.5 cycles to 1 minute.
Causes:
• Faults in the transmission or
distribution network
• Connection of heavy loads and
start-up of large motors
Effects:
• Tripping of contactors and electro-magnetic relays
• Disconnection and loss of efficiency in electric
rotating machines
8. VOLTAGE SWELL
Momentary increase of the voltage, at the power
frequency, outside the normal tolerances, with the
duration of more than one cycle and typically less than
few seconds.
Causes:
Start/stop of heavy loads, badly dimensioned power
sources, badly regulated transformers (mainly during
off-peak hours).
Effects:
Data loss, flickering of lighting and screens, stoppage or
damage of sensitive equipment, if the voltage values
are too high.
9. VOLTAGE FLUCTUATION & FLICKERING
Fluctuation is oscillation of voltage value. And
flickering is a visible change in brightness of lamp
Causes:
Arc furnaces, frequent start/
stop of electric motors,
oscillating loads.
Effects:
• Most consequences are common
to under-voltages.
• Filament of can be damaged.
• Reduction in life of electrical equipment
10. VOLTAGE UNBALANCE
A voltage variation in a three-phase system in
which the three voltage magnitudes or the phase angle
differences between them are not equal.
Causes:
Large single-phase loads
(induction furnaces, traction loads),
incorrect distribution of all
single-phase loads
(this may be also due to a fault).
Effects:
Unbalanced systems imply the existence of a negative
sequence that is harmful to all three phase loads. The
most affected loads are three-phase induction
machines.
11. HARMONIC DISTORTION
Voltage or current waveforms assume non-
sinusoidal shape. The waveform corresponds to the
sum of different sine waves with different magnitude
and phase, having frequencies that are multiples of
power-system frequency.
Causes:
• Classic sources: arc furnaces,
welding machines, rectifiers and
DC brush motors.
• Modern sources: all non-linear loads
Effects:
Increased probability in occurrence of resonance,
overheating of all cables and equipment, loss of
efficiency in electric machines, electromagnetic
interference with communication systems.
12. NOISE
Superimposing of high frequency signals
on the waveform of the power-system
frequency.
Causes:
• Electromagnetic interferences.
• Improper grounding.
Effects:
Disturbances on sensitive electronic
equipment usually not destructive. May cause
data loss and data processing errors.
13. SHORT INTERRUPTIONS
Interruption of electrical supply for a duration
of few milli seconds to one or two seconds.
Causes:
• Mainly due to opening and
automatic enclosure of
protection devices
• Insulation failure, lightning and
insulation flash-over
Effects:
• Tripping of protection devices, loss of information
and malfunction of data processing equipment.
• Stoppage of sensitive equipment, such as PCs, PLCs,
if they are not prepared to deal with this situation.
14. LONG INTERRUPTIONS
Total interruption of electrical supply for
duration greater than 1 to 2 seconds.
Causes:
Equipment failure in the power system
network, storms and objects
striking lines or poles, fire,
human error, bad coordination
or failure of protection devices.
Effects:
Stoppage of all the equipment
18. Distribution Static Compensators
Inject the pulses which are exactly 180 degrees out
of phase of the unwanted harmonics , thus cancelling
out the unwanted harmonics and yielding the output
wave, very close in nature to the fundamental wave
19. Static VAR Compensators
Static VAR compensators (SVR) use a combination of capacitors
and reactors to regulate the voltage quickly.
Solid-state switches control the insertion of the capacitors and
reactors at the right magnitude to prevent voltage from fluctuating.
20. Transient Voltage Surgé suppressors
(TVSS)
• Transient voltage surge
suppressors are used as
interface between the
power source and sensitive
loads, so that the transient
voltage is clamped by the
TVSS before it reaches the
load.
• It has a component with a
nonlinear resistance that
limits excessive line voltage
and conduct any excess
impulse energy to ground.
22. Noise Filters
Noise filters are used to
avoid unwanted frequency current
or voltage signals (noise) from
reaching sensitive equipment.
This can be accomplished by
using a combination of capacitors
and inductances that creates a
low impedance path to the
fundamental frequency and high
impedance to higher frequencies,
that is, a low-pass filter.
23. Unified Power Quality Conditioning
• It is the combination of DVR and DSTATCOM
•Shunt active filters eliminate the harmonics,
•Series active filters allow the passage of only the
fundamental wave.
24. IMPACT ON SOCIETY AND ENVIRONMENT
The mitigation of all the power quality related issues leads
to the economic operation of the power system.
A technically sound quality of power will be supplied to the
equipments, thereby leading to their smooth operation and
ensuring a long life for them.
The elimination of harmonics and other issues leads to the
proper operation of the system, thereby eliminating the
unwanted vibrations and keeping the system stable.
The reactive power is compensated at an acceptable and
affordable cost and thus, the system efficiency improves.
The power factor is improved; this leads to a heavy savage
in the costs of electricity bills.
Above all, the problem of power pollution is eliminated.
25. Conclusion
• POWERQUALITY maintenanceis an important aspect for
theeconomic operation of a system.
• So, Proper mitigationdevices can be used to maintainthe
level of power quality as desired.