Germany gears up to test 20MW wind turbines

Germany’s Fraunhofer Institute for Wind Energy Systems (IWES) is gearing up to launch a mobile grid test simulator that will assess the impact of mammoth wind turbines with outputs of as much as 20MW, thanks to a €12.7 million grant from the German Government.

Fraunhofer IWES is launching its mobile test facility for grid compliance tests research project, or Mobil-Grid-CoP, which is aiming to develop and commission a mobile grid simulator which will serve to verify current and future grid system services as well as the electrical properties of wind turbines.

Importantly, however, the Mobil-Grid-CoP will allow for the testing and optimisation of the grid compatibility of mammoth wind turbines – with the current focus being on wind turbines with individual capacity of up to 20MW.

The world’s largest wind turbine about to enter serial production is the 12MW GE Haliade-X turbine, but manufacturers are actively developing ever-larger turbines with the hope of delivering 20MW turbines by the end of the decade.

With wind turbines of such magnitude on the horizon a testing setup is necessary, as current test benches – which provide accelerated testing of the electrical properties of wind turbines – cannot cope with turbine output in excess of 15MW.

Enter Fraunhofer IWES’ Mobil-Grid-CoP which will be able to simulate various grid connection points and dynamic grid events for testing prototypes directly in the field. The simulator will not only be able to test grid errors but will also be able to test for dynamic frequency changes so as to analyse the supply of active power from the turbine and examine its effects on the overall system.

The Mobil-Grid-CoP will also be able to simulate scenarios such as blackouts so as to test the grid restoration capacity of power grids with such mammoth variable electricity sources as 20MW offshore wind turbines.

The project is expected to run for three years and commissioning of the Mobil-Grid-CoP is expected for the fall of 2022.

“In Mobil-Grid-CoP, Fraunhofer IWES is developing the world’s largest grid simulator with an output of 80 MVA,” said Professor Jan Wenske, Deputy Head of the Institute and Technical Director of Fraunhofer IWES. “For one thing, this can be integrated seamlessly into our existing DyNaLab (Dynamic Nacelle Testing Laboratory) test structure and, for another, it can be used in the open field. Furthermore, it will also be able to be connected to the planned hydrogen test field.”

“We are delighted by the positive feedback and the specific technical requirements of industry which we will integrate into the specifications for the test facility,” said Torben Jersch, Head of the System Technology department at Fraunhofer IWES, speaking at the presentation of Mobil-Grid-CoP to an international industrial circle.

“The mobile grid simulator will be connected directly to the grid connection point at a test site,” added Gesa Quistorf, project manager at Fraunhofer IWES. “The 80 MVA grid simulator enables the testing of objects up to an output of 20 MW, meaning that even entire wind farms and strings can be measured. Furthermore, active disturbance analysis during operation on the grid is possible.”