Nordex Group and the Fraunhofer-Institut fur Windenergiesysteme (IWES) have developed a new approach to integrating wind turbines with the grid.
Their research has resulted in a hardware-in-the-loop (HiL) test bench to validate wind turbines in isolation on a grid simulator.
In order to operate when connected to the grid, wind turbines have a fault-ride-through capacity in order to not detach itself from the grid during sudden voltage drops or peaks.
Evidence of this must be provided during the development process and market launch of wind turbines. In the past, manufacturers have provided evidence of these properties with a complex measuring routine on prototype turbines in the field.
With the new HiL system, all other components of the wind turbine are simulated in real time and the test bench can be operated regardless of the weather. A first generator and converter configuration has already been successfully tested and certified “in the laboratory”.
Michael Franke, Vice President Global Engineering of the Nordex Group said: “Field validations of turbine system properties are necessary but time-consuming. Added to this is the difficulty of finding a suitable site for the test series. Measurement of the electrical grid properties of a turbine in the field takes more than 12 months until certification.
“The same test on the IWES test bench has now been completed in three months – a saving of nine months. This test bench represents a major step forward for both partners as it makes a faster time to market possible.”
Dr Andreas Reuter, Director of Fraunhofer, IWES, added: “Thanks to its flexibility and functionality, the test bench is also ideally equipped for the expected future requirements for verification.”