Turbine CAD? OEM and software developer join forces
November 9, 2011 by Paul Dvorak
Filed under Turbine Design, Wind Power News, Wind Power Software
Parametric Technology Corp. says its software has capabilities and related processes extend throughout a product's lifecycle.
Wind-turbine developer Goldwind Science & Technology Co. Ltd., announced it would partner with software developer Parametric Technology Corp. to offer a lifecycle management system as part of its product line. Headquartered in Needham, Mass., the software company develops engineering design, analysis, and management software to over 25,000 users in industrial, high-tech, aerospace & defense, automotive, and medical-device industries. The announced engineering software is expected to help Goldwind design more products more efficiently than previously possible.
Parametric Technology Corp.
www.ptc.com
Alarm software texts you when things go awry
October 6, 2011 by Windpower Engineering
Filed under Condition Monitoring, Maintenance, Maintenance & operations, Wind Power Software
TopView software lets users configure alarms, monitor remote processes, signal notifications, and more. The software is a comprehensive, cost-effective alarm management and notification program that’s useful when data must be monitored, such as in wind turbines and other non-manned facilities. The software lets users quickly respond to abnormal conditions. Users can customize notification messages and directions for each monitored point so they know the problem and its precise location. It also allows a cascading queue of alarm notifications to recipients and launches other apps in response to alarms. For process data, it works safely and seamlessly with existing SCADA, PLC, or Historian products.
Exele
www.exele.com
WPE
How predicting failure improves reliability
October 5, 2011 by Windpower Engineering
Filed under Turbine Design, Wind Power Software
Engineers working to increase product quality and reliability will find a working knowledge of statistics invaluable. Design teams can use a conventional test-and-improve cycle or a more formal DMAIC (define, measure, analyze, improve, and control) sequence. However, this part of product development is too critical to simply toss “over the wall” to a test-department.
Without adequate attention and understanding of applicable statistics, much design and development can be a mystery. Questions that often arise include: How many samples should be used? How long should the test run? What do test results mean? How can one quickly calculate accurate figures for a total design reliability?
A system’s overall reliability is the product of its components’ reliabilities. Any component required for successful system operation is treated as a series or chain relationship. Reliability is also, by definition, 1.0 minus the probability of failure within a specified period.
A complex piece of equipment has multiple parts that succeed or fail under specific conditions. A failure means the component no longer performs to a predetermined definition of its function. In addition, a group of “identical components” often fails in a time relationship that may typically be described by a statistical distribution.
Weibull analysis is excellent for calculating this failure distribution. It is flexible and has sufficient parameters to describe a variety of real-life situations. Though commonly referred to as a distribution, a Weibull analysis calculation is simply a statistical curve-fit routine. It works by fitting a smooth curve to what may be noisy or rough data. One represents the data from individual components of a system by two or three Weibull parameters. One can then treat the reliability of the complete system as the product of the reliabilities of individual components. Finally, the best guarantors of reliability are project engineers who care about their work. Let’s look at a wind turbine to see how the analysis works.
F/S refers to Failed/Suspended tests. Order is statistically adjusted to correct for one of the tests being suspended. Median Rank is a system to estimate the midpoint of the interval represented by each data point. Weibull-Ease software calculates the table.
Component groups include a controller, rotor, transmission, generator, brake, and yaw drive. Structural members and safety issues are included. Starting with the control group, correlate stress duration to a variable that can apply to all components.
Megawatt-hours, or sometimes just hours, is a logical variable because most failure modes relate well to these easily measured values.
Once this is established, tests will all correlate to megawatt-hours generated under agreed upon stress levels with all tests documented and correlated to megawatt-hours.
Processing the initial data
This data, generated by tests under controlled conditions can be loaded into standard Weibull analysis routines. Each data (failure) point is arranged by value, and then assigned median rank figures. These figures are generated as part of standard routines. The median rank values adjust the data slightly to help remove intrinsic bias.
A Weibull routine calculates a scale and shape parameters. The procedures are available in a number of texts in the box For further reading.
A third parameter, X, of the Weibull routine is an intentional “offset” value subtracted from or added to each data point. Its value is selected to improve the correlation coefficient of the least squares regression fit of the data. It is determined by an iterative process that operates to find the closest local maxima of this correlation coefficient with respect to this offset.
The analysis would be repeated for all eight of the component groups of a wind turbine (each may have different failure modes) that are critical to the turbine’s function. Once a couple groups are completed, the rest are simply a repetition of these.
The next step consolidates the data generated from all eight of these component groups into a single relationship to represent the complete system. Weibull-Ease software is one such routine for doing just this, calculating and accurately representing the reliability of a complete system by a single equation.
When we processed the original data, the first component failure mode was identified as Mode #1 and assigned so by the Multiple Mode Reliability model. When finished entering this mode, as mode #1, other modes are entered simply clicking the “Retrieve Saved Mode” button and repeating the process.
Next, we do a complete time (in this case, megawatt-hours) sweep and record as discussed in the box, Regarding components critical to successful system operation.
Equivalent Weibull model
In addition to evaluating of each individual failure mode, we have managed to re-fit all modes into a single Weibull model of the complete system (the wind turbine design) with its own unique set of parameters. This total system includes confidence limits. These are based on the least reliable mode. This serves to assure the figures will be conservative.
The figures generated in the Multiple mode reliability model show the chance or probability of a single disabling problem requiring maintenance effort within the system.
WPE
Gear software for design and analysis
September 7, 2011 by Kathleen Zipp
Filed under Mechanical Components, Wind Power Software, Wind Turbine Gearboxes
The input window for the design portion of Excel-Lent Gear software.
Gear and gearbox manufacturer Excel has developed software that the company says quickly determines maximum product parameters for gears needed in various industries. The Excel-Lent software is said to save engineers a lot of time when designing pinion and gear or a gearbox.
With minimal input the Design portion of the software will calculate the number of teeth in the pinion and gear, DP or Module, face width etc. required to transmit the power, within a few seconds. The calculated data can be exported to the “Analysis” section for complete analysis with clicking the “Transfer Data “ tab on screen. Calculated capacity will be very close to the required power.
Also, the company says the Excel-Lent software’s dimensioning program is versatile. Non-standard center distance or matching a new gear to an existing gear can be done by clicking the indicated option. The material tables provided have all the commercially available materials listed, with heat treat and mechanical properties to allow the user to choose any gear material from the list to fit their need.
The analyze screen from the software.
“Although commercial software has long been available in the gear industry, it has been too expensive or too complicated to be used by engineers without specialized gear design knowledge, ” says Excel president N.K. Chinnusamy. “The software is specifically designed with a user-friendly interactive input screen providing defaults and options in accordance with the AGMA 2001 standard (American Gear Manufacturers Association).” The users of Excel-Lent software can easily navigate through the input screens to edit, analyze and produce reports on the optimum gear and gearbox design for various industrial and other applications.
The analyze screen from the software.
He continues that the software is not designed for any specific industry. It can be used for machine tools, heavy materials handling equipment or even the wind turbine industry. For the wind turbine industry, for example, the designer needs a full understanding of all the operating loads on the gear members to arrive at the required power rating.
The key calculations performed are the AGMA power rating and load calculations, including bending strength geometry
factor (J) and pitting resistance geometry factors (I). Output from the software is a single page of data printed in a format that is easy to read and interpret. Other commercial software typically prints five or six pages of information, which may be confusing to most design engineers unless they are gear experts, according to Chinnusamy.
The company says that users of Excel-Lent need not be familiar with AGMA standards to use the software. Those who are not gear engineers can also benefit from the gear engineering knowledge embedded in the software package.
A demo
The Excel Gear website now includes a demo to show the simplicity of the Excel-Lent Gear software. The demo takes a few minutes to download, and then runs through the numerical design of a spur gear needed to carry 350 hp at 1250 rpm and do so for 10,000 hr. The selections should be familiar to most mechanical engineers and include values such as the materials, mesh ratio, and safety factors. Results appear quickly in a green field at the screen bottom. A detailed sheet with many more of the gear characteristics also appears quickly after hitting the Calculate button. This information can be transferred to the included analysis program, with one button push, to calculate load and life values. Interpreting an analysis will take some experience. Values found here include yield, bending, and contact stresses for the gear and pinion. Lastly, a Dimensions program provides the inspection data for the gears. Three input screens from the software appear here. The company is also announcing a cost of $995 for first time users.
Excel Gear Inc.
Trends in simulation software
May 17, 2011 by Windpower Engineering
Filed under Turbine Design, Wind Power Software
General purpose finite-element analysis has proven itself very successful at finding stresses in structures if you assume a steady load. But wind turbines present a range of engineering challenges that arise from large displacements, non-linear material properties, and time varying loads from air flows, conditions which challenge general purpose structural analysis. For these applications it is often better to investigate a multiphysics approach using Computational Fluid Dynamics combined with structural and multibody dynamics solvers to arrive at a solution. The general trend for the industry is to model every possible element in a wind farm development, from the financials to structures to finding the best turbine layout across proposed terrain. Because of this brief space, let’s look at three engineering areas.
CFD software traditionally assisted with aircraft design. But recent trends are toward a wide range of specialized and focused simulation applications that assist with tasks such as composite blade optimization, and dynamic studies of blade and tower assemblies. The wind industry has also encouraged development of software for detailed rotor aerodynamics, wake predictions, and vortex induced vibration from offshore platforms and vortex induced motion.
“Multi-physics simulations are an emerging capability within computational fluid dynamics,” says Altair Engineering’s senior CFD analyst and Program Manager, David Corson. “Historically, CFD software focused on predicting fluid and thermal transport. Recent advances let us include additional physics into the simulation flow field. One area with significant implication for wind-turbine design is Fluid-Structure Interaction. For instance, as turbine blades are designed longer and use new materials, deflection under wind load becomes increasingly important. In high wind, for instance, a blade could deflect enough to hit the tower. But will it? This software can give a good indication. Turbine designers must also consider how a blade’s aerodynamic performance changes with deflection, and then fatigue concerns arising from blade deflections,” says Corson.
Few CFD solvers contain techniques for simulating such behavior in wind turbines. One possible approach to solving this problem utilizes a modal analysis of the wind turbine. Wind loading on blades (the fluid and structure) provides excitation of various vibration modes of the blades, and the resulting deformation is the sum of each modal contribution. All fluid and structural computations are performed by the CFD solver, so there is no run-time coupling of the solver to external codes. A second technique that works well for larger (nonlinear) bending applications, involves run-time coupling to external structural dynamics codes, yielding a coupled Fluid-Structure Interaction method. “This lets users couple the CFD software to a preferred structural solver,” says Corson. Specialized coupling algorithms handle the interpolation between dissimilar meshes (between structural model and fluid model) and communication requirements. Programs of this sort often allow running structural and CFD codes on different computers using different operating systems.
Offshore wind turbines prompt additional questions because they sit on towers driven deep into the ocean floor. “Strong currents can produce vortex-induced vibration and motion of risers and platforms. This leads to fatigue damage or sea bed erosion,” says Altair Engineering Energy Industry spokesperson, Shing Pan. “Experience with offshore oil platforms lets software such as AcuSolve provide validated solutions in this area to help predict tower stresses from wave motion and vortex action. The software helps optimize designs by taking into account changes in current speed and direction that often vary with depth.”
Simulation software has been developed to analyze a wide range of effects, such as wave motion, multiple structures, riser shapes, and motions including nonlinear response. What’s more, the software can tell of interactions with sea bottom and other complex problems, and transient-turbulent processes including boundary layer phenomena, separation, and free shear of wakes.
Other areas in which CFD provides insight include the aerodynamics of steady, transient, and moving rotors; siting studies that allow examining macro, micro and wake predictions; and just as important are noise predictions from high resolution transient simulations. Simulation software can also assist with the best practices and the design of experiments.
Software for designing the layout of wind farms is also going under frequent upgrades. Commercially available programs allow inputting information such as terrain models, historic wind data, performance graphs of selected turbines, and location identifiers. The software then considers wake effects and wind probabilities to calculate annual power outputs from each turbine and the entire farm. Adjusting locations allows finding a layout with the maximum payout.
WPE
Software assists with wind-farm layouts
May 7, 2011 by Windpower Engineering
Filed under Turbine Design, Wind Power Software
Sarah Herman
WindFarmer Specialist
GL Garrad Hassan
Austin, Texas
www.gl-garradhassan.com
Wind-farm designs and energy assessments are complex processes that vary greatly depending upon the constraints and challenges of each site. Stakeholders such as developers, utilities, and financiers must technically evaluate a project to determine its profitability and feasibility. Software that can model the performance of all types of farms is essential in the wind industry. Some key features and models needed in such wind-farm design software are highlighted here, using the latest WindFarmer 4.2 software developed by GL Garrad Hassan as a platform for discussion. A number of features in the software come from years of development and hence deserve attention. For example:
The graphic user interface on WindFarmer software shows a few selections and results for a large proposed layout. Panels on the left show selections and those on the right, calculations. The graph inset describes a turbulence model.
Energy calculations: Energy-production values calculated for a wind farm require several inputs to properly evaluate a site’s estimated energy generation. The topography for a wind farm and its site boundaries can be loaded into the software as ESRI shape files. The wind flow should be characterized from on-location measurements and extrapolated to the rest of the site. Its historical air density must also be evaluated.
Efficiencies and loss factors specific to the site should be understood, and a turbine layout and power curve must be selected. Once this basic site information is entered, the type of analysis method chosen to calculate energy depends on the characteristics of the wind farm being assessed.
A wind farm’s energy production greatly depends on the wake effects from upwind turbines. Hence, an accurate wake model is key to an accurate estimate. WindFarmer software has several wake models that can consider specific challenges found in the broad range of wind farms in development and operation.
Wind-farm wake modeling: The Eddy Viscosity Wake Model is a CFD model developed, refined, and validated using operational wind-farm data for many years. The model provides a successful wake-modeling algorithm for a wide variety of common situations. The software also includes several modifications to this base model for wind farms that fall outside a normal operational envelope of the model. With these adjustments, the exceptional characteristics of regions with such observed wind regimes can be taken into account.
Wakes in complex terrain: Environmental parameters such as air density and turbulence levels as well as development of the wake are a function of the underlying topography. Based on the turbine’s position in the terrain, the software adjusts turbine-wake development and the energy calculated.
The inset image suggests how the wind farm will appear from ground level.
Closely spaced wind farm layouts: A closely spaced wake model allows completing wake modeling on wind farms that are built for one or two-directional wind regimes. This type of wind farm has unique challenges. Such regimes lend themselves to turbine layouts that are positioned close together in one direction to maximize electricity generation per given area. Turbine wakes in such a layout do not propagate independently, and so must be modeled differently. The software’s Eddy Viscosity Model for Closely Spaced Turbines effectively models wakes propagated for this type of wind farm by altering the classic Eddy Viscosity model and letting velocity deficits caused by the wake effects add cumulatively.
Large wind-farm model: As the wind industry has developed, the size of wind farms has increased on and offshore to include some that are greater than 100 MW in size and many rows deep. A Large Wind Farm Wake Model simulates increased wakes generated by large wind farms. The model works by considering several characteristics specific to large wind farms, the most important being alterations to the boundary layer caused by the presence of many turbines extracting momentum from the atmosphere. As a result, the wind profile varies across the farm, an effect analogous to an increase in surface roughness length. Within WindFarmer, this technical and crucial feature is engaged with a check box where the software performs all analysis of upstream turbines to derive added wake losses due to the large wind-farm wake effect. The Large Wind Farm Wake Model has been tested and validated with operating offshore and onshore data. Furthermore, the speed of the energy yield calculation – typically 10 to 15 minutes for a 100-turbine array – lets wind farm designers explore many different layout options within a reasonable timeframe.
Data from site assessments display in WindFarmer showing an inset wind rose of wind speed and directional probability along with a contour map of color coded wind-energy levels.
Uncertainty analysis: Once a site’s estimated energy production calculations complete, the uncertainty associated with the results must be quantified. Uncertainty calculations are essential to quantify and assess the asset’s viability and profitability to raise project financing. As such, the software includes uncertainty analyses into its results to evaluate the many sources of uncertainty present within the development process, such as data collection sensors, topographic modeling, and yearly variations of the on-site wind regime. These uncertainties derive the relevant exceedance levels so stress cases can run and debt-service coverage ratios converted into currency for pro forma preparations.
Efficient wind farm design: Software for designing wind farms offer a range of tools to support the engineer designing a productive wind farm. These tools include aids for automatic generation of both random and symmetric layouts with high-energy yield. Using the advanced tools to design a wind farm can help mitigate project deficiencies found later in the detailed energy assessment. As wind farms become larger and more complex, scientific research is increasing understanding of how wakes behave within such a complex environment. Software such as WindFarmer is essential to leverage this knowledge and produce reliable estimates of electrical-power production.
WPE
Free software predicts composite stiffness
April 12, 2011 by Windpower Engineering
Filed under Turbine Design, Wind Power Software
A manufacturer of high-performance composite fabrics has released the latest version of its laminate-analysis software, VectorLam Cirrus. The new version offers better tools for comparing and evaluating stiffness, strength, weight, and cost in a composite part. The software has a metric-unit option on a Summary page, hull-side laminates on the DNV page, and more deflection limit options. Also new: navigating between laminates from the “Build a Laminate” screen.
Vectorply Corp.
www.vectorply.com
Software for long-range resource planning
March 30, 2011 by Kathleen Zipp
Filed under Wind Power Software
Map of ERCOT nodal market. In addition to ERCOT, the other six ISOs in the United States use Ventyx analytics software for generation and transmission planning.
ABB companyVentyx has a PowerBase Suite license contract with U.S.-based ISO Electric Reliability Council of Texas (ERCOT). The company’s software adds long-range resource planning analysis capability to nodal electricity market operations.
The PowerBase Suite—which includes PROMOD IV, MarketPower, and Simulation-Ready Data—will be used for long-range resource planning analysis including: nodal and zonal market price forecasting, ancillary service analysis, intermittent resource analysis and generation expansion and retirement analysis in ERCOT’s new nodal market system, operational since December 2010. ERCOT also recently implemented the Network Manager Market Management System (MMS) from Ventyx to administer its wholesale power market in the United States.
Ventyx www1.ventyx.com
Free software predicts composite stiffness
March 4, 2011 by Windpower Engineering
Filed under Construction, Wind Power Site Simulation
A manufacturer of high-performance composite fabrics has released the latest version of its laminate-analysis software, VectorLam Cirrus. The new version offers better tools for comparing and evaluating stiffness, strength, weight, and cost in a composite part. The software has a metric unit option on a Summary page, hull-side laminates on the DNV page, and more deflection limit options. Also new: navigating between laminates from the “Build a Laminate” screen.
Vectorply Corp.
www.vectorply.com
A new way to try before you buy
November 15, 2010 by Kathleen Zipp
Filed under Wind Power Site Simulation, Wind Power Software
A web-based analytical tool is available from a manufacturer of small wind power systems (2.5 kW to 100 kW). XZERES Wind Corporation’s WindRx offers a comprehensive site assessment and financial review to quickly assist potential customers who are considering purchasing a wind turbine from the company. The tool integrates wind resource data, energy production data based on specific site characteristics, government incentives (state and federal), and financing options to generate a detailed economic return profile for customers. It has the capability to perform “what if scenarios” that tailors to most customers’ situations. WindRx can generate a report that shows key decision parameters such as out of pocket cost, payback period, and net savings over the life of the equipment. The report will also provide a detailed review of yearly cash flows, site specific information, monthly energy production of the wind turbine system, and return on investment (NPV, IRR).
WindRx asks important questions needed to make sustainable energy choices. Does wind make economic sense for a particular site location? What does it cost? What federal and state incentives are available? Does the site location have the right wind resource? What does a feed-in tariff mean? How much energy will it give me and at what cost? Is wind energy a smart investment for me? WindRx(TM) makes small wind energy information more easily accessible. Additionally, as a web-based tool, an XZERES certified seller will have this tool in the field, at any time with internet access.
XZERES Wind Corp designs, develops, manufactures and markets distributed generation, wind power systems for the small wind (2.5kW-100kW) market. The company’s grid connected and off grid wind turbine systems, which consist of 2.5-kW and 10-kW devices and related equipment, are used for electrical power generation for applications and markets such as residential, micro-grid based rural electrification, agricultural, small business, rural electric utility systems, as well as other private, corporate infrastructure and government applications.
XZERES www.xzeres.com
