Control Scheme for a Stand-Alone Wind Energy Conversion SystemRoja Rani
Energy is the considered to be the pivotal input for development.
At present owing to the depletion of available conventional resources and concern regarding environmental degradation, the renewable sources are being utilized to meet the ever increasing energy demand.
Due to a relatively low cost of electricity production wind energy is considered to be one of the potential sources of clean energy for the future.
This report gives an overview of patenting activity around Doubly-fed Induction Generators (DFIG) used in the horizontal axis wind turbines for efficient power generation. Patents were categorized as per key DFIG technologies and analyzed for generating different trends within PatSeer Project.
Control Scheme for a Stand-Alone Wind Energy Conversion SystemRoja Rani
Energy is the considered to be the pivotal input for development.
At present owing to the depletion of available conventional resources and concern regarding environmental degradation, the renewable sources are being utilized to meet the ever increasing energy demand.
Due to a relatively low cost of electricity production wind energy is considered to be one of the potential sources of clean energy for the future.
This report gives an overview of patenting activity around Doubly-fed Induction Generators (DFIG) used in the horizontal axis wind turbines for efficient power generation. Patents were categorized as per key DFIG technologies and analyzed for generating different trends within PatSeer Project.
In this presentation a brief introduction is given on parts of wind turbine, classification of wind turbines, importance of wind turbines, current status like installed capacity (annual and cumulative) . Then there is a explanation on theory behind the design of wind turbine blades i.e, AERODYNAMICS OF WIND TURBINES which includes explanation about shape of an aerofoil, its different parameters, lift force, drag force, different equations about lift drag force, NACA profiles, Blade Element Momentum Theory, etc.
Wind power or wind energy is the use of wind to provide the mechanical power through wind turbines to turn electric generators and traditionally to do other work, like milling or pumping. Wind power is a sustainable and renewable energy, and has a much smaller impact on the environment compared to burning fossil fuels.
Wind Power History
Advantages & Disadvantages
Wind Turbine & Components
Power From Wind Mill
Swept area Of Wind Mill Rotor
Wind Speed Variation with Height
Density & Temperature Variation with Height
Global Wind Patterns
Wind Speed Measurements
Wind Speed Distribution
Weibull Probability Distributions
These slides present at an introduction level about the demand side management and demand response in smart micro-grid system. Later mathematical modelling and detail on optimization techniques will be covered.
As the fifth in a series of tutorials on the power system, Leonardo ENERGY introduces its minute lecture on voltage and frequency control, using the analogy of a metal/rubber plate to demonstrate the centralised nature of frequency control, whereas voltage control is more a local matter.
Until we know that large wind turbines/mills to generate electricity. But the technology advanced such that these wind turbines came to our home for our domestical use. In this ppt I discussed about new small residential wind turbines by which we can reduce our electrical bills and more. Have a look!
In this presentation a brief introduction is given on parts of wind turbine, classification of wind turbines, importance of wind turbines, current status like installed capacity (annual and cumulative) . Then there is a explanation on theory behind the design of wind turbine blades i.e, AERODYNAMICS OF WIND TURBINES which includes explanation about shape of an aerofoil, its different parameters, lift force, drag force, different equations about lift drag force, NACA profiles, Blade Element Momentum Theory, etc.
Wind power or wind energy is the use of wind to provide the mechanical power through wind turbines to turn electric generators and traditionally to do other work, like milling or pumping. Wind power is a sustainable and renewable energy, and has a much smaller impact on the environment compared to burning fossil fuels.
Wind Power History
Advantages & Disadvantages
Wind Turbine & Components
Power From Wind Mill
Swept area Of Wind Mill Rotor
Wind Speed Variation with Height
Density & Temperature Variation with Height
Global Wind Patterns
Wind Speed Measurements
Wind Speed Distribution
Weibull Probability Distributions
These slides present at an introduction level about the demand side management and demand response in smart micro-grid system. Later mathematical modelling and detail on optimization techniques will be covered.
As the fifth in a series of tutorials on the power system, Leonardo ENERGY introduces its minute lecture on voltage and frequency control, using the analogy of a metal/rubber plate to demonstrate the centralised nature of frequency control, whereas voltage control is more a local matter.
Until we know that large wind turbines/mills to generate electricity. But the technology advanced such that these wind turbines came to our home for our domestical use. In this ppt I discussed about new small residential wind turbines by which we can reduce our electrical bills and more. Have a look!
Ocean Thermal Energy Conversion (OTEC) is a marine renewable energy technology that converts solar radiation to electrical power by the temperature difference between the deep cold ocean water and warm tropical surface water.
Ocean Thermal Energy Conversion SystemsNaveen Kumar
OTEC or OCEAN THERMAL ENERGY CONVERSION, is a renewable energy technology that converts solar radiation to electric power by use of the world oceans. The use of OTEC as a source of electricity will help reduce the state’s almost complete dependence on imported fossil fuels. About one fourth of the 1.7 * 1013 watts of solar energy reaching the earth’s atmosphere is absorbed by sea water. OTEC can be considered as an indirect solar technology because the surface water are warmed by the sun. OTEC can also be used to produce ammonia, hydrogen, aluminium, chlorine and other chemicals.
Performance Evaluation of 830kW Wind Turbine and an Analysis of Various Param...Rohan Raibagkar
The project aimed at
1) Understanding the performance of wind power project of 830KW
2) Determining system reliability (Grid availability, Machine availability, System availability) and
operating hours of the wind conversion system from the data obtained at site
3) Analyzing the effect of various parameters like velocity, blade length, temperature, pressure, air
density on the power generation of a wind turbine
4) Forecasting or Predicting the performance of the wind turbine generators based on the above
parameters
This analysis can be used to existing sites which are nearby the above evaluated wind power project for Maximizing power generation
It helps us to understand effect of various parameters viz. air density, air pressure, air temperature, blade length, velocity on the power generation
According to the results, there is a high effect of air characteristics on the mechanical power.
The environment’s parameter has a massive effect on the generated power, which will lead the researchers to concentrate on it with highest priority
Complete one year data was used for the analysis of the wind power project
Results were executed using Matlab
Luis Vega from the National Marine Renewable Energy Center describes the technical and economic aspects of Ocean Thermal Energy Conversion (OTEC). Slides from the REIS seminar series at the University of Hawaii at Manoa on 2009-10-01.
Renewable energy is generally electricity supplied from sources, such as wind power, solar power,
geothermal energy, hydro power and various forms of biomass. The popularity of renewable energy
has experienced a significant upsurge in recent times due to the exhaustion of conventional power
generation methods and increasing realization of its adverse effects on the environment. Wind energy
has been harnessed for centuries but it has only emerged as a major part of our energy solution quite
recently and this report focus on utilizing wind energy by using vertical axis wind turbine.
Among the Renewable Energy Sources, Wind Energy is taken up with careful prior efforts before implementation as it requires all capital and technical inputs before payback starts. However, it is a clean source of electric power compared to coal based thermal power. India is a country that has made progress in wind power investment.
Design Construction, Simulation and Testing of A 300W Wind-Powered Battery Ch...theijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
When designing a power generation project from a different source, and in our case study, wind, when calculating the annual energy produced, it is necessary to define and calculate the losses incurred in the system. The main cause of losses in a wind park is due to the oscillations caused by the turbulence of the air around the turbine because of roughness of terrain. The paper describes two methods of estimating turbulence intensity: one based on the mean and standard deviation (SD) of wind speed from the nacelle anemometer, the other from mean power output and its SD. These analyses are very important for understanding the fatigue and mechanical stress on the wind turbines. Then significance of the site ruggedness index (RIX) and the associated performance indicator (ΔRIX) are confirmed for terrain and the consequences of applying WAsP outside its operating envelope are quantified.
Economic viability and profitability assessments of WECS IJECEIAES
Technical and technological advances in alternative energy sources have led many countries to add green energy to their power plants to reduce carbon emissions and air pollution. At present, many electricity companies are looking to use alternative sources of energy because of high electrical energy prices. Wind energy is more useful than many renewable energies such as solar, heat, biomass, etc. The Wind Energy Conversion System (WECS) is a system that converts the kinetic energy of the wind into electrical energy to feed the known loads. WECS can be found in a variety of technology. Climate change and load demand are essential determinants of WECS optimization modelling. In this paper, proposed a strategy focused primarily on economic analysis WECS. The strategy based on a weather change to find the optimal designing and modelling for four different types of WECS using HOMER software. Finally, several criteria were used to determine which type of WECS was the most profitable investment and less payback period.
Measures for prevention, control and abatement of environmental pollution in river Ganga and to ensure continuous adequate flow of water so as to rejuvenate the river Ganga.
Let's dive deeper into the world of ODC! Ricardo Alves (OutSystems) will join us to tell all about the new Data Fabric. After that, Sezen de Bruijn (OutSystems) will get into the details on how to best design a sturdy architecture within ODC.
Kubernetes & AI - Beauty and the Beast !?! @KCD Istanbul 2024Tobias Schneck
As AI technology is pushing into IT I was wondering myself, as an “infrastructure container kubernetes guy”, how get this fancy AI technology get managed from an infrastructure operational view? Is it possible to apply our lovely cloud native principals as well? What benefit’s both technologies could bring to each other?
Let me take this questions and provide you a short journey through existing deployment models and use cases for AI software. On practical examples, we discuss what cloud/on-premise strategy we may need for applying it to our own infrastructure to get it to work from an enterprise perspective. I want to give an overview about infrastructure requirements and technologies, what could be beneficial or limiting your AI use cases in an enterprise environment. An interactive Demo will give you some insides, what approaches I got already working for real.
GraphRAG is All You need? LLM & Knowledge GraphGuy Korland
Guy Korland, CEO and Co-founder of FalkorDB, will review two articles on the integration of language models with knowledge graphs.
1. Unifying Large Language Models and Knowledge Graphs: A Roadmap.
https://arxiv.org/abs/2306.08302
2. Microsoft Research's GraphRAG paper and a review paper on various uses of knowledge graphs:
https://www.microsoft.com/en-us/research/blog/graphrag-unlocking-llm-discovery-on-narrative-private-data/
The Art of the Pitch: WordPress Relationships and SalesLaura Byrne
Clients don’t know what they don’t know. What web solutions are right for them? How does WordPress come into the picture? How do you make sure you understand scope and timeline? What do you do if sometime changes?
All these questions and more will be explored as we talk about matching clients’ needs with what your agency offers without pulling teeth or pulling your hair out. Practical tips, and strategies for successful relationship building that leads to closing the deal.
Accelerate your Kubernetes clusters with Varnish CachingThijs Feryn
A presentation about the usage and availability of Varnish on Kubernetes. This talk explores the capabilities of Varnish caching and shows how to use the Varnish Helm chart to deploy it to Kubernetes.
This presentation was delivered at K8SUG Singapore. See https://feryn.eu/presentations/accelerate-your-kubernetes-clusters-with-varnish-caching-k8sug-singapore-28-2024 for more details.
UiPath Test Automation using UiPath Test Suite series, part 4DianaGray10
Welcome to UiPath Test Automation using UiPath Test Suite series part 4. In this session, we will cover Test Manager overview along with SAP heatmap.
The UiPath Test Manager overview with SAP heatmap webinar offers a concise yet comprehensive exploration of the role of a Test Manager within SAP environments, coupled with the utilization of heatmaps for effective testing strategies.
Participants will gain insights into the responsibilities, challenges, and best practices associated with test management in SAP projects. Additionally, the webinar delves into the significance of heatmaps as a visual aid for identifying testing priorities, areas of risk, and resource allocation within SAP landscapes. Through this session, attendees can expect to enhance their understanding of test management principles while learning practical approaches to optimize testing processes in SAP environments using heatmap visualization techniques
What will you get from this session?
1. Insights into SAP testing best practices
2. Heatmap utilization for testing
3. Optimization of testing processes
4. Demo
Topics covered:
Execution from the test manager
Orchestrator execution result
Defect reporting
SAP heatmap example with demo
Speaker:
Deepak Rai, Automation Practice Lead, Boundaryless Group and UiPath MVP
Essentials of Automations: Optimizing FME Workflows with ParametersSafe Software
Are you looking to streamline your workflows and boost your projects’ efficiency? Do you find yourself searching for ways to add flexibility and control over your FME workflows? If so, you’re in the right place.
Join us for an insightful dive into the world of FME parameters, a critical element in optimizing workflow efficiency. This webinar marks the beginning of our three-part “Essentials of Automation” series. This first webinar is designed to equip you with the knowledge and skills to utilize parameters effectively: enhancing the flexibility, maintainability, and user control of your FME projects.
Here’s what you’ll gain:
- Essentials of FME Parameters: Understand the pivotal role of parameters, including Reader/Writer, Transformer, User, and FME Flow categories. Discover how they are the key to unlocking automation and optimization within your workflows.
- Practical Applications in FME Form: Delve into key user parameter types including choice, connections, and file URLs. Allow users to control how a workflow runs, making your workflows more reusable. Learn to import values and deliver the best user experience for your workflows while enhancing accuracy.
- Optimization Strategies in FME Flow: Explore the creation and strategic deployment of parameters in FME Flow, including the use of deployment and geometry parameters, to maximize workflow efficiency.
- Pro Tips for Success: Gain insights on parameterizing connections and leveraging new features like Conditional Visibility for clarity and simplicity.
We’ll wrap up with a glimpse into future webinars, followed by a Q&A session to address your specific questions surrounding this topic.
Don’t miss this opportunity to elevate your FME expertise and drive your projects to new heights of efficiency.
State of ICS and IoT Cyber Threat Landscape Report 2024 previewPrayukth K V
The IoT and OT threat landscape report has been prepared by the Threat Research Team at Sectrio using data from Sectrio, cyber threat intelligence farming facilities spread across over 85 cities around the world. In addition, Sectrio also runs AI-based advanced threat and payload engagement facilities that serve as sinks to attract and engage sophisticated threat actors, and newer malware including new variants and latent threats that are at an earlier stage of development.
The latest edition of the OT/ICS and IoT security Threat Landscape Report 2024 also covers:
State of global ICS asset and network exposure
Sectoral targets and attacks as well as the cost of ransom
Global APT activity, AI usage, actor and tactic profiles, and implications
Rise in volumes of AI-powered cyberattacks
Major cyber events in 2024
Malware and malicious payload trends
Cyberattack types and targets
Vulnerability exploit attempts on CVEs
Attacks on counties – USA
Expansion of bot farms – how, where, and why
In-depth analysis of the cyber threat landscape across North America, South America, Europe, APAC, and the Middle East
Why are attacks on smart factories rising?
Cyber risk predictions
Axis of attacks – Europe
Systemic attacks in the Middle East
Download the full report from here:
https://sectrio.com/resources/ot-threat-landscape-reports/sectrio-releases-ot-ics-and-iot-security-threat-landscape-report-2024/
From Daily Decisions to Bottom Line: Connecting Product Work to Revenue by VP...
Power from wind in india
1. WIND ENERGY ENGINEERING
Wind Electric Conversion Systems
* Wind Energy Availability
• Energy in wind, speed
• Wind Turbine, Design
• Variables – wind power density
• Generator and power output
• PV-Wind, Diesel-set-Wind Hybrid System
• Tower design
• Wind Electric Conversion System
economics
2. 2
Wind Energy Engineering Syllabus-1
Wind energy Assessment by
Measurement and instrumentation –
Beaufort number -Gust parameters –
Wind type – power law index -Betz
constant -Terrain value.
Energy in wind– study of wind data
and applicable Indian standards –
Steel Tables, Structural Engineering
for tower design- Wind farms––
fatigue stress – Tower design.
3. 3
Wind Energy Engineering Syllabus-2
Wind Energy Conversion Systems: Variables
– wind power density – power in a wind
stream – Wind turbine efficiency – Forces on
the blades of a propeller –Solidity and
selection curves.
Horizontal Axis –WT and Vertical Axis -WT-
Power duration curves- wind rose diagrams -
study of characteristics - actuator theory-
Controls and instrumentations.
Grid-Connected WECS and Independent
WECS- Combination of WECS and diesel
generator, Battery storage – Wind Turbine
Circuits.
4. 4
CL 716 WIND ENERGY
ENGINEERING: Text & Reference Books
1. S. Rao & B. B. Parulekar, “Energy Technology”,
3rd Edition, Khanna publishers, 1995.
2. Wind and Solar Power Systems, Mukund. R.
Patel, 2nd Edition, Taylor & Francis, 2001
3. Wind Energy Handbook, Edited by T. Burton, D.
Sharpe N. Jenkins and E . Bossanyi, John Wiley
& Sons, N.Y. 2001
4. . L .L. Freris, Wind Energy Conversion Systems,
Prentice Hall, 1990.
5. D. A. Spera, Wind Turbine Technology:
Fundamental concepts of Wind Turbine
Engineering, ASME Press
5. 5
From wind to electricity.
The first wind powered electricity was produced in
1888. It had a rated power of 12 kW (direct current - dc).
In the 1930's the first large scale AC turbine was constructed
in the USA.
In the 1970's the fuel crises sparked a revival in R & D
work in America (USA and Canada) and Europe (Denmark,
Germany, the Netherlands,Sweden and the UK) and
modern wind turbine-generators were developed. This was
achieved due to improvements in aerodynamic and
structural design, materials technology and mechanical,
electrical and control engineering and led to capablilty to
produce several megawatts of electricity.
6. 6
Wind power is
economically viable.
Over the last two decades, there has been a
tremendous amount of technical
improvement in wind turbines. Their costs
have increased by about a factor of 9, due to
more advanced controls, materials, and
engineering, but at the same time their
energy production has increased by a factor
of 56, leading to a net decline in the cost per
watt of a factor of more than six. Wind power
is thus rapidly becoming economically viable.
9. 9
Kinetic energy >
Mechanical
[Rotational] >
Electrical energy
Wind turbines convert the
kinetic energy in wind into
mechanical power that runs a
generator to produce
electricity.
10. 10
horizontal-axis vs vertical-axis
There are two basic designs of wind electric
turbines: vertical-axis, or "egg-beater" style,
and horizontal-axis (propeller-style)
machines.
Horizontal-axis wind turbines are most
common today, constituting nearly all of the
"utility-scale" (100 kilowatts, kW, capacity and
larger) turbines in the global market.
13. 13
Wind power for developing countries
Large-scale grid connected wind turbines
are common with wind farm; This can be
the main national network, in which case
electricity can be sold to the electricity
utility.
Micro-grids distribute electricity to smaller
areas, typically a village or town. When
wind is used for supplying electricity to
such a grid, a diesel generator set is often
used as a backup for the periods when
windspeeds are low.
15. 15
Performance of WECS
The availability of wind resources are
governed by the climatic conditions of the
region concerned- for which wind survey is
extremely important to exploit wind energy.
Performance of W E C S depends upon:
Subsystems like
wind turbine (aerodynamic),
gears (mechanical),
generator (electrical) and Control (electronic)
16. 16
Wind Electric Potential in India
Gross
Potential: 45,000 MW
Technical Potential:13,000
MW
Sites with Annual Average
Wind
Power Density > 200
watts/m2
generally viable, 208 such
sites
in 13 states identified
States with high potential :
Gujarat, Andhra Pradesh,
Tamil Nadu, Karnataka,
Kerala, Madhya Pradesh,
and Maharashtra.
17. 17
India’s Installed Wind Power
Gen Capacity at end of 2001
State Installed capacity, MW
Tamil Nadu 828
Maharashtra 236
Gujarat 167
Andhra 92
Karnataka 50
M.P. 23
All Others 111
18. 18
Wind resources
Apart from having a good wind turbine, the
most critical aspects for the success of
investment in the wind energy sector are
having a good site and
an accurate assessment of the wind
resource at the site.
21. 21
Choosing an exact location for the
monitoring tower:
Place the tower as far away as possible
from local obstructions to the wind
Select a location that is representative of
the majority of the site.
23. 23
anemometer
An instrument for measuring the force or
velocity of wind. There are various types:
A cup anemometer, is used to measure
the wind speed from the speed of rotation
of a windmill which consist of 3 or 4
hemispherical or conical cups, each fixed
to the ends of horizontal arms attached to
a vertical axis.
A Byram anemometer is a variety of cup
anemometer.
24. 24
A counting anemometer has cups or a fan whose
rotation is transmitted to a counter which integrates
directly the air movement speed.
A hand anemometer is small portable anemometer
held at arm's length by an observer making a wind
speed measurement.
A pressure tube anemometer (Dines anemometer)
is an instrument that derives wind speed from
measurements of the dynamic wind pressures. Wind
blowing into a tube develops a pressure greater
than the static pressure, while wind blowing across
a tube develops a pressure less than the static. This
pressure difference is proportional to the square of
the wind speed.
29. 29
For wind data from selected stations,
essential attributes are:
Station location
Local topography
Anemometer height and exposure
Type of observation (instantaneous or
average)
Duration of record.
30. 30
Topographic maps
provide the analyst with a preliminary look
at other site attributes, including:
Available land area
Positions of existing roads and dwellings
Land cover (e.g., forests)
Political boundaries
Parks
Proximity to transmission lines.
31. 31
For verifying site conditions items of
importance include:
Available land area
Land use
Location of obstructions
Trees deformed by persistent strong winds (flagged
trees)
Accessibility into the site
Potential impact on local aesthetics
Cellular phone service reliability for data transfers
Possible wind monitoring locations.
32. 32
Cost – economics-1
The cost of producing electricity form the wind is
heavily dependent on the local wind regime.
The power output from the wind machine is
proportional to cube of the windspeed and so a
slight increase in windspeed will mean a
significant increase in power and a subsequent
reduction in unit costs.
Capital costs for windpower are high, but running
costs are low and so access to initial funds,
subsidies or low interest loans are an obvious
advantage when considering a wind-electric
system.
33. 33
Cost – economics-2
If a hybrid system is used a careful cost-
benefit analysis needs to be carried out.
A careful matching of the load and
energy supply options should be made to
maximise the use of the power from the
wind - a load which accepts a variable
input is ideally matched to the intermittent
nature of windpower.
34. 34
WIND RESOURCE ASSESSMENT-
India- Implemented through :
(i) State Nodal Agencies
(ii) Centre for Wind Energy Technology (C-
WET)
Financial Assistance :
(i) Full establishment costs of Wind Resource
Assessment Project (WRAP) of C-WET by
the Central Government.
35. 35
WIND RESOURCE ASSESSMENT
Implemented through…. :
(ii) The cost of setting up the wind monitoring
stations would be shared between MNRE
and State Nodal agencies in 80:20 ratio,
except for North-eastern and hilly States,
where it would be in 90:10 ratio.
36. 36
Resource Survey in India
Centre for Wind Energy Technology (C-WET)
Chennai.
6 Volumes of “Wind Energy –Resource Survey in
India” , containing wind data have been published
Master Plans for 87 sites prepared and available
from C-WET at nominal cost.
Wind data available from C-WET on CD ROM.
37. 37
Government of India
Ministry of New and Renewable Energy
(Wind Power Division)
Block No.14, CGO Complex,
Lodhi Road, New Delhi – 110003
•C-WET would evaluate the eligibility of manufacturer,
who approaches for Type. Certification, as per the
evaluation criteria in vogue, which is being followed by C-
WET.
•Validity of Self-Certification facility for models specified in
the List of Models and Manufacturers thereof issued by C-
WET is extended up to 30th September, 2007.
•Self-Certification facility would be available for a
maximum period of 18 months from the date of signing of
the agreement with C-WET for the models hereinafter
including in the category "Model under Testing and
Certification at C-WET" in the List to be issued by C-WET.
41. 41
Wind Turbine, tail, support tower
The amount of power a turbine will
produce depends primarily on the
diameter of its rotor.
The diameter of the rotor defines its
“swept area,” or the quantity of wind
intercepted by the turbine.
The turbine‟s frame is the structure onto
which the rotor, generator, and tail are
attached. The tail keeps the turbine
facing into the wind.
43. 43
Horizontal Axis upwind
Wind Turbine
Most turbines today are Horizontal Axis
upwind machines with two or three
blades, made of a composite material like
fiberglass.
44. 44
Some definitions:
Solidity: In reference to a wind energy
conversion device, the ratio of rotor blade
surface area to the frontal, swept area that
the rotor passes through.
wind rose: A diagram that indicates the
average percentage of time that the wind
blows from different directions, on a monthly
or annual basis.
power curve: A plot of a wind energy
conversion device's power output versus
wind speed.
power coefficient: The ratio of power
produced by a wind energy conversion
device to the power in a reference area of
the free wind stream.
49. 49
Some definitions….
1 m/s = 3.6 km/h = 2.237 mph = 1.944 knots
1 knot = 1 nautical mile per hour = 0.5144 m/s =
1.852 km/h = 1.125 mph
average wind speed: The mean wind speed over a
specified period of time.
PITCH CONROL: A method of controlling the
speed of a wind turbine by varying the orientation,
or pitch, of the blades, and thereby altering its
aerodynamics and efficiency.
50. 50
Tip Speed Ratio
The tip-speed is the ratio of the rotational speed
of the blade to the wind speed. The larger this
ratio, the faster the rotation of the wind turbine
rotor at a given wind speed. Generation requires
high rotational speeds. Lift-type wind turbines
have maximum tip-speed ratios of around 10.The
tip speed ratio (λ = ΩR/v), R Wind turbine blade
radius (m), Ω Wind turbine rotor angular speed
(rpm), v Wind speed [m/s].
51. 51
Operating Characteristics
All wind machines share certain operating
characteristics, such as cut-in, rated and cut-
out wind speeds.
Cut-in Speed
Cut-in speed is the minimum wind speed at which the
wind turbine will generate usable power. This wind speed
is typically between 7 and 10 mph.
Rated Speed
The rated speed is the minimum wind speed at which the
wind turbine will generate its designated rated power. For
example, a "10 kilowatt" wind turbine may not generate 10
kilowatts until wind speeds reach 25 mph. Rated speed
for most machines is in the range of 25 to 35 mph.
52. 52
Rated Speed…
At wind speeds between cut-in and rated, the
power output from a wind turbine increases
as the wind increases. The output of most
machines levels off above the rated speed.
Most manufacturers provide graphs, called
"power curves," showing how their wind
turbine output varies with wind speed.
54. 54
Cut-out Speed
At very high wind speeds, typically between
45 and 80 mph, most wind turbines cease
power generation and shut down. The wind
speed at which shut down occurs is called
the cut-out speed. Having a cut-out speed is
a safety feature which protects the wind
turbine from damage. Shut down may occur
in one of several ways. In some machines an
automatic brake is activated by a wind speed
sensor.
55. 55
Cut out speed & yaw
Some machines twist or "pitch" the blades to
spill the wind. Still others use "spoilers," drag
flaps mounted on the blades or the hub which
are automatically activated by high rotor
rpm's, or mechanically activated by a spring
loaded device which turns the machine
sideways to the wind stream. Normal wind
turbine operation usually resumes when the
wind drops back to a safe level.
56. 56
number of blades
The number of rotor blades and the total area they
cover affect wind turbine performance. For a lift-
type rotor to function effectively, the wind must flow
smoothly over the blades.
To avoid turbulence, spacing between blades
should be great enough so that one blade will not
encounter the disturbed, weaker air flow caused by
the blade which passed before it.
It is because of this requirement that most wind
turbines have only two or three blades on their
rotors
57. 57
Transmission- Gear box
The number of revolutions per minute (rpm)
of a wind turbine rotor can range between
40 rpm and 400 rpm, depending on the
model and the wind speed.
Generators typically require rpm's of 1,200
to 1,800. As a result, most wind turbines
require a gear-box transmission to increase
the rotation of the generator to the speeds
necessary for efficient electricity production.
59. 59
Electrical Generators
It converts the turning motion of a wind
turbine's blades into electricity. Inside
this component, coils of wire are rotated
in a magnetic field to produce electricity.
Different generator designs produce
either alternating current (AC) or direct
current (DC),
60. 60
generators for wind turbines
At the present time and for the near future,
generators for wind turbines will be
synchronous generators,
permanent magnet synchronous
generators, and
induction generators, including the squirrel-
cage type and wound rotor type.
64. 64
generators for SMALL wind
turbines
For small to medium power wind turbines,
permanent magnet generators and squirrel-cage
induction generators are often used because of
their reliability and cost advantages. Induction
generators, permanent magnet synchronous
generators, and wound field synchronous
generators are currently used in various high
power wind turbines.
65. 65
Induction generator
Induction generator offers many advantages over a
conventional synchronous generator as a source of
isolated power supply.
Reduced unit cost, ruggedness, brush less (in
squirrel cage construction), reduced size, absence
of separate DC source and ease of maintenance,
self-protection against severe overloads and short
circuits, are the main advantages
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induction generator…
Further induction generators are loosely
coupled devices, i.e. they are heavily damped
and therefore have the ability to absorb slight
change in rotor speed and drive train
transient to some extent can therefore be
absorbed.
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drawback of the induction
generator
Reactive power consumption and poor
voltage regulation under varying speed are
the major drawback of the induction
generators, but the development of static
power converters has facilitated the control of
induction generator, regarding output voltage
and frequency.
68. 68
Synchronous generator
Synchronous generators are closely coupled
devices and when they are used in wind
turbines which is subjected to turbulence and
requires additional damping devices such as
flexible couplings in the drive train or to
mount gearbox assembly on springs and
dampers.
70. 70
range of output power ratings.
Generators are available in a large
range of output power ratings.
The generator's rating, or size, is
dependent on the length of the wind
turbine's blades because more energy is
captured by longer blades.
72. 72
Applications adapted to run on
DC.
• Storage systems using batteries store DC
and usually are configured at voltages of
between 12 volts and 120 volts in USA.
• A typical 100 W battery-charging machine
has a shipping weight of only 15 kg.
73. 73
A .C. Generators…..
• Generators that produce AC are
generally equipped with features to
produce the correct voltage (120 or 240
V) and
• constant frequency (60 / 50 cycles) of
electricity, even when the wind speed is
fluctuating.
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Advantages of Induction
generator over synchronous
Induction generator offers many advantages over a
conventional synchronous generator as a source of
isolated [A .C] power supply.
Reduced unit cost, ruggedness, brush less (in
squirrel cage construction), reduced size, absence
of separate DC source and ease of maintenance,
self-protection against severe overloads and short
circuits, are the main advantages
75. 75
Environmental Aspects of
Power Generation Using WECs
Wind turbines are most environment friendly method
of producing electricity.
They do not pose any adverse effect on the global
environment, unlike the conventional coal or oil-fired
power plants. The pollution that can be saved per
year from a typical 200 kW wind turbine, involving of
substitution of 120 - 200 tonnes of coal which
contain pollution contents as, Sulphur dioxide
(SO2): 2 –3 tonnes, Nitrogen oxide (NOX): 1.2 to
2.4 tonnes, and other particulates of 150-300 kg. .
76. 76
Audible noise
The wind turbine is generally quiet. The wind turbine
manufacturers generally supply the noise level data
in dB versus the distance from the tower.
A typical 600 kW wind turbine may produce 55 dB
noise at 50 meter distance from the turbine and 40
dB at a 250 meter distance [4, 22] comparable with
the noise level in motor car which may be
approximately 75 dB.
This noise is, however, is a steady state noise. The
wind turbine makes loud noise while yawing under
the changing wind direction. Local noise ordinance
must be compiled with.
77. 77
Towers
Tower on which a wind turbine is mounted is
not just a support structure. It also raises the
wind turbine so that its blades safely clear
the ground and so it can reach the stronger
winds at higher elevations.
Maximum tower height is optional in most
cases, except where zoning restrictions
apply. The decision of what height tower to
use will be based on the cost of taller towers
versus the value of the increase in energy
production resulting from their use.
78. 78
Towers….
Studies have shown that the added
cost of increasing tower height is often
justified by the added power generated
from the stronger winds.
Larger wind turbines are usually
mounted on towers ranging from 40 to 70
meters tall.
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The tower must be strong enough to
support the wind turbine and to sustain
vibration, wind loading and the overall
weather elements for the lifetime of the
wind turbine.
Tower costs will vary widely as a function
of design and height.
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Research and development
Research and development is going on to make
wind power competitive with fossil fuel and nuclear
power in strict sense, without taking into account of
wind power‟s social factors such as environment
benefits.
Efforts are being made to reduce the cost of wind
power by: design improvement, better
manufacturing technology, finding new sites for wind
systems, development of better control strategies
(for output and power quality control), development
of policy and instruments, human resource
development, etc
81. 81
About Enercon - E-30-230 kW-
Gearless type--1
Variable speed drive, Continuous pitch
regulation,
Starts gen. at low speed of 2.5 m/s,
Gearless construction, no transmission loss,
Synchronous gen., draws < one % reactive
power from grid,
By using AC_DC_AC conversion, pumps the
power at „grid frequency‟,
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About Enercon - E-30-230 kW-
Gearless type--2
Produces power at all loads at near unity
power factor without using capacitors
Supply reactive power to the grid to improve
grid power factor
Slow speed generator of maximum 50 rpm
Three independent air breaks, no
mechanical breaks
Lightning protection
83. 83
Wind Turbine Design
Design efforts benefit from
knowledge of the wind speed distribution and
wind energy content corresponding to the
different speeds and
the comparative costs of different systems to
arrive at the optimal rotor/generator combination.
Optimizing for the lowest overall cost considers
design factors such as relative sizes of rotor,
generator, and tower height.
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Thanks to extensive R&D efforts during the
past 30 years, wind energy conversion has
become a reliable and competitive means for
electric power generation.
The life span of modern wind turbines is
now 20-25 years, which is comparable to many
other conventional power generation
technologies.
The average availability of commercial wind
power plants is now around 98%.
Thank You