New ECN Control System to Increase Wind Turbine Yield
ECN introduces an advanced control system that individually adjusts wind turbine blades. This makes it possible to construct larger wind turbines that generate up to 13% more energy.
It is a well-known fact that wind energy production costs of large wind turbines are lower and the yield is higher. However, a problem with large turbines is that the wind load on the rotor blades is greater. ECN and wind turbine manufacturer XEMC-Darwind have come up with a solution.
Smart control, greater yield
The new control system of ECN and XEMC-Darwind individually controls each of the three rotor blades and adjusts them. Project leader Stoyan Kanev of ECN: “A computer programme continuously measures wind load, adjusting the position of the blades accordingly. A smarter adjustment of the rotor blades reduces the load and allows lighter and cheaper wind turbines to be designed. The result is a better financial yield. It is now possible to design wind turbines with rotor blades that are roughly 6.3 percent larger. This means you can generate 13 percent more energy.”
The control system (Individual Pitch Control) of ECN was tested on a large scale at ECN’s own wind turbine test farm in Wieringermeer for a long period. This is quite unique, because these types of systems had previously only been tested in simulations. For the test, a wind turbine was used with a rotor diameter of 115 metres, the XD 115 of XEMC-Darwind.
”We spent two months field-testing the system in accordance with the international IEC certification standard. We have now proved that it works. The results are even better than in the simulations. Tests have shown that the load on the rotor blades is reduced to 20%. We are very happy with this result,” says Kanev. Even though the system was designed for offshore wind farms, it can also be applied to wind turbines on land.
Research will continue
The advanced control system was designed within the framework of the FLOW research programme. As part of this programme, thirteen Dutch companies and knowledge institutions work together to identify innovative ways of reducing offshore wind farm costs. ECN will continue its research into reducing the costs and increasing the yield of turbines and wind farms.