Giants of the air but still tied to the ground
They reach heights of 200 m, boast a circumference of up to 130 m and can supply over 5,000 households with electricity – that's right, wind turbines. As a source of clean, renewable energy, wind turbines rely solely on the power of the wind.
Global warming and the catastrophic events related to it – severe storms, floods, etc. – have finally convinced the world's governments to begin cutting back on the amount of harmful CO2 gases released into the atmosphere. To achieve this, the amount of oil and coal burned to generate energy must be reduced and replaced by other sources. The future lies in renewable sources of energy such as hydropower, solar power, biomass and wind power. The usable energy that could be gained from wind alone would be enough to cover the energy needs of the entire planet 50 times over.
Satisfying China's hunger for energy
A geography that is very favorable for wind – huge gusty steppes in the north and west and thousands of kilometers of coastline in the east and south – leads us into the Middle Kingdom. Currently the largest exporter on the planet, China has a monstrous appetite for energy, which makes the wide use of clean wind energy the perfect solution. The Chinese government has recognized this and has granted generous subsidies in order to get the industry up and running more quickly.
Wind turbines are being installed both on land and offshore. Robustness and reliability have the highest priority, because, for example, offshore systems can only be reached for servicing by helicopter when the weather cooperates. The high concentration of salt compounds in the air near the coast is also one of the biggest challenges facing the components involved. The substantial differences in temperatures that affect continental climates – up to +50°C in summer and down to -40°C in winter – and the vibrations caused by the constant rotation of the blades add to the difficult conditions. Wind turbines are designed to operate for more than 20 years, which means that the automation components themselves must be able to withstand this harsh environment as well.
The X20 system from B&R: Overcoming extreme conditions
The X20 System proved to be extremely well suited to these challenges. During a test established for the aviation industry that can also be used for wind turbines, the X20 achieved outstanding results. The test is designed to determine the limits of the device by cycling through extreme temperature changes while being subjected to constant vibration. This makes it possible to draw conclusions about existing reserves and the estimated service life of the product. According to statements from the manager of the external testing agency, the X20 goes far beyond the limits of products from other manufacturers that are on the market.
These excellent results – together with the availability of numerous modules that can be used for the many different tasks – make this the perfect system for use in wind turbines. A special X20 module can measure and monitor key parameters such as voltage, frequency and phasing of the power mains while simultaneously calculating the amount of energy output by the wind turbine. A network module handles optical data transfer over the lengthy connection between the X20 modules at the foot of the wind turbine and the modules situated in the enclosure at the top of the tower.
openSAFETY technology allows new safety strategies and increases convenience
The most dangerous situation that must be prevented in a wind turbine is rotor overspeed. This can cause one of the blades to break and fly off the turbine. With a mass of several tons per blade and a rated peak speed of around 300 km/h, the damage caused by careening components could be devastating. This is why the safety technology used in wind turbines also plays such an important role. Integrated Safety technology based on openSAFETY relies on seamless integration in the X20 System to eliminate the need for double wiring and also to offer extensive diagnostic functions. At the same time, completely new safety strategies and concepts can be implemented with the highest level of safety and convenience.
The actual brain of a wind turbine is the application software used to control the giant blades. Many established design and engineering companies offer software solutions to control the system in addition to designing the mechanical and electrical aspects of a wind turbine. The openness of the B&R system allows fast and efficient integration. Another possibility is the industry-specific software platform from B&R. Making adjustments for the respective wind turbine (customizing) is done on site. Large and experienced wind turbine manufacturers are capable of developing the entire system controller themselves.
Reduced commissioning times with automatic code generation
Clever closed-loop control algorithms maximize energy yield and minimize load on the machine components in the system. To simulate the physics of the wind turbine, mathematic models are used that make it possible to test the application software in the office, therefore shortening the commissioning time. Highly complex algorithms and models are normally developed with the help of simulation tools and must then be properly compiled for the automation architecture. An especially elegant and efficient method for this is automatic code generation; for example, algorithms and models developed with MATLAB® and Simulink® can be automatically compiled as high-performance programming code with a mouse click by linking to the Automation Studio Target for Simulink® software. The compiled algorithms and models are immediately available in the Automation Studio for further use.
The outstanding remote diagnostic functions provided by the B&R system make it easy to access all important parameters and data for each wind turbine, even after commissioning. As a result, maintenance intervals can be better planned and service work can be scheduled much more efficiently.
Successful commissioning of various systems impressively demonstrates again and again the capabilities of the efficient development tools and the excellent diagnostic possibilities. Sleek, elegant hardware solutions make new strategies and increased functionality possible, even while lowering costs. The high quality and long availability of B&R products guarantees customers ideal conditions over the entire product life cycle.