In Search of Better Wind Turbines
Product development project management of wind energy generators is a complex process that can benefit from a single collaborative approach.
By Karun Chakravarthy
Solution Experience--Energy, Process & Utilities
Wind turbine manufacturers are constantly innovating with new designs, materials, and manufacturing processes to continuously improve the performance of wind turbines. It is critical for companies to innovate to differentiate themselves in this highly competitive market environment. Innovation not only includes new product concepts such as gearless direct drives and intelligent controls, but also production methods such as automated manufacturing to increase standardization and adoption of best production practices and to improve product quality. Companies can then manufacture the same products at several factories worldwide closer to the wind farms where these products will be deployed, enabling greater manufacturing flexibility and thereby reducing logistics and transportation costs.
Innovations in composite blades provide wind turbine manufacturers with an excellent opportunity to improve their product while reducing costs. Failures of wind turbine blades during the operations phase can be quite expensive—about $200,000 for blade replacement and $200,000 for installation. With advanced composites design and simulation software, composite blades can be designed for optimal performance and weight and virtually tested to validate the behavior under various operating conditions to ensure maximum performance and reliability of the wind turbine.
Wind turbine manufacturers are looking for ways to standardize their production processes and be in the most competitive position for expected future demand for wind turbines, especially from off-shore wind farms. It is not uncommon for manufacturers to face quality challenges during the production of composite blades, including high rejection rates due to the complexity of the manufacturing process and the correlation of the variables involved.
Product Development Project Management
Management of wind turbine product development is a complex process, given the diverse engineering, testing and manufacturing disciplines and the globalization of these departments. The program duration of a new wind turbine design is typically five years. Companies need to be able to develop innovative products and bring them to market quicker. Traditionally, each department implemented its own system to maintain the project data, which resulted in duplication of data, lack of traceability and no standardization of processes leading to significant project delays and cost overruns.
Managing the project development process on a single collaborative platform across departments enables concurrent engineering between design, testing and manufacturing. Companies can reduce the time needed to validate the design, enable early start of production, and reduce time to market. By providing design with early feedback, issues can be detected much earlier in the development process, thereby eliminating costly manufacturing problems and delays.
Stakeholders in all disciplines, as well as suppliers, can have access to the accurate and up-to-date information. This provides full traceability ensuring that the project requirements and goals will be met. Project managers have the latest project information such as budget, resource allocation, issues and risks to take appropriate decisions for projects to be executed on time and on budget. Companies across several industries, including wind turbine manufacturers, typically experience a 14% reduction in time-to-market, 25% reduction in project management time and 8% improvement in engineering efficiency.
Composite Blade Design
Blades are one of the most critical components of the wind turbine. The design of composite blades involves the design of a complex blade surface, the plies, manufacturability studies, aerodynamics analyses, and tests for stress and fatigue. Manufacturers focus on innovation in blade design, such as optimizing the number of plies and blade weight. Such tasks require close interaction and iteration between all teams—design, analysis, and manufacturing—during blade development. For many blade manufacturers, preliminary design, detailed design, analysis, and manufacturing of composite blades are often “siloed” processes. Data exchange between each disparate system may require considerable time and effort, as they do not share a common information backbone.
Innovation in blade design requires close interaction and iteration between all teams to manage all aspects of composite blade development from preliminary design all the way to testing and structural certification.
Advanced Simulation and Optimization
Wind turbines operate at various sites across the globe under varied operating conditions and have to withstand extreme temperature and climatic conditions such as ice, hail and hurricanes. Blades are subjected to large variations in stress while operating in different conditions throughout the year. Even during a single cycle, blades experience varying stresses due to increasing wind speeds with altitude and wake effects of surrounding blades, which have a fatigue effect on the blades.
It is very important to predict the real-world behavior of the turbine under all of these conditions to ensure maximum performance and reliability. Wind turbine manufacturers are subjected to very high warranty costs if the blade has to be replaced during operation. The goal is to maximize the availability of the turbine for its entire life, which is about 20 years.
Many companies develop physical prototypes to test the performance of wind turbine components. This can cost more than $1 million and can take up to one year to complete, depending on the complexity of the blade design. Advanced simulations enable manufacturers to accurately predict complex real-world behavior of the turbines. This includes vibrations, nonlinear deformation and stresses, fracture and failure, and multiphysics effects, like fluid-structure interactions. Manufacturers can perform sensitivity studies, identify optimum design parameters, and quickly engineer market-leading wind turbines. By performing these analyses virtually, companies can reduce their development costs and time.
Manufacturing to Increase Throughput and Quality
Many wind turbine manufacturers are seeking solutions to lower costs—and to quickly ramp up their production—while increasing quality. Manufacturing planning in a virtual environment allows companies to plan and validate the manufacturing processes in a virtual 3D environment, enabling them to identify and resolve issues up front and to manufacture products “right the first time.” Doing so lowers manufacturing costs, while increasing wind turbine quality.
Companies need to continue to innovate in the face of increased competition from low-cost manufacturers. Many are adopting automated production methods, such as using robots for composite manufacturing processes. Such automated methods provide them with greater flexibility to complete most of the work in a single station, allowing them to produce multiple products in a single manufacturing facility. Automated manufacturing of composite blades reduces waste compared to manual processes, saving the company money. Exposure of shop-floor workers to toxic composite materials is also minimized, improving health and safety.
Automation in manufacturing enables companies to standardize their best practices across all their global manufacturing facilities. Companies can then utilize local manufacturing, using factories that are close to the wind farm site where the wind turbine will be installed, to produce the wind turbine components, thereby reducing their logistics and transportation costs.
Investments in automated production systems incur high capital costs. By validating the production systems in a virtual environment, manufacturers can verify if these systems can enable the company to achieve its goals, which can help it justify the capital investment.
Composite Blade Production and Quality Control
Production of composite blades is a challenging process that involves controlling several variables and understanding the correlation between them. Companies experience very high rejection rates during blade production (even greater than 25%). Even a small improvement in the rejection rate can save a company millions of dollars per year.
A number of production defects, such as voids, wrinkles and delamination, can cause blades to be scrapped. It is hard to isolate the cause of the defects, since they can occur even if all the variables are within the permissible range, due to the complex correlation between them.
Traditional methods like SPC (statistical process control) are just not sufficient to solve these challenges. These methods require a very large number of data points to be statistically relevant, which may be too expensive to measure or just impossible to get in context of composites manufacturing.
A unique solution from Dassault Systèmes provides a data-driven, rule-based continuous process improvement methodology for blade manufacturing and is ideal for monitoring and controlling production quality. It is based on inductive logic programming that aims to identify the right combination of parameters to achieve the right product quality. The solution can work with a small set of data points, and continuously improves the production process based on the results, in real time. Monitoring shop-floor data helps quantify the risk of defects aiding customers to get the process back under control. With this solution, customers can develop “agile process control,” enabling experts to extract, optimize, and validate a robust set of easy-to-read operational best practices.
A leading blade manufacturer in Europe was having severe problems with a defect rate as high as 50%. With the use of the solution, the defects have been reduced to 25% and the company’s next goal is to reduce the defect rate to 5%.
To be successful in the challenging environment in which they operate, wind turbine and blade manufacturers need a best-in-class engineering, simulation and manufacturing solution that addresses all their challenges. Solutions such as the Sustainable Wind Turbines 3DEXPERIENCE provides a single platform backbone, integrating information from all disciplines and applications. It provides a collaborative environment allowing all users and stakeholders to work concurrently and collaboratively. As a result, companies will develop and deliver better performing wind turbines faster in a more global and competitive environment.
This article was first published in the 2013 edition of the Energy Manufacturing Yearbook.