Offshore wind farm control strategies put to the test

Friday February 2, 2018 13:52

New project launched to field test wind farm control (WFC) strategies to maximise energy production from offshore wind whilst reducing turbine loads.

The Demowind 2 project ‘Wind Farm Control Trials’ will demonstrate how effective implementation of control strategies can reduce the cost of offshore wind. It will investigate the impact of strategies that aim to improve energy generation across an entire wind farm, rather than individual turbines.

The project is backed by innogy, Statoil, EnBW, E.ON, and Vattenfall. It will incorporate know-how from experts who have played a leading role in wind farm control concept generation and wind measurements, including ECN, DTU, Frazer-Nash Consultancy and Windar Photonics. The project is coordinated by The Carbon Trust within its offshore wind accelerator programme.

Optimising control strategies to reduce wake effects will help to lower the cost of energy.  This is achieved by increasing the total wind energy yield and reducing fatigue, thus saving both operational as well as maintenance costs. Additionally, the introduction of control strategies can also increase availability and extend the lifetime of existing and future assets.

Stoyan Kanev, Senior Project Manager at ECN: “This project will be the first and most comprehensive to demonstrate the economic benefits from wake control in real-life experiments at a full-scale offshore wind farm. It will increase the maturity and acceptance of the technology, paving the way towards a large scale implementation.”

Different methods of control will be used to optimise power production for the whole wind farm rather than maximising production of individual turbines. The turbine operation will be altered by adjusting the blade angle of attack (pitch) and rotation of the nacelle (yaw). These two concepts were patented by ECN more than a decade ago and this project will make a big step towards industry acceptance.

The project aims to build on previous simulation-based studies[1]. Based on these previous studies and simulations undertaken, it is expected that adopting blade pitch or yaw-based WFC strategies would result in increase in energy yield of between 0.5 and 3.5 per cent. It is also expected to possibly enable load reductions of up to 50 per cent for some wind turbine components meaning increased component life therefore reduced operation and maintenance costs. The project will seek to verify and validate these theories by implementing WFC strategies at an operational wind farm. The first stage of the project involves analysis to determine the most suitable wind farm test site for the trials and an optimisation of the control strategies. The trials are expected to start in the summer of 2018, with the full results available at the end of 2019.

The selected wind farm will have extensive measurement equipment installed as part of the validation process for the simulations, including eight nacelle-mounted Windar Photonics LiDARs[2], a scanning LiDAR and load measurements installed on individual turbines.

Despite the wealth of evidence showing the potential benefits of this technology, technical and economic risks pose a challenge for bringing it to market. The project has been set up with the aim of demonstrating the effectiveness of WFC strategies in an operational setting. Once proven, the concept can be rolled out to operational offshore wind farms across the wider industry.

 

For further information about the work of ECN in this project, please contact Stoyan Kanev via our online contact form.  


[1] FP7 ClusterDesign, Dutch FLOW program, NREL activities and earlier studies by the OWA.

[2] LiDAR – Light detection And Ranging technology is a laser-based sensor installed offshore to determine the upstream wind direction of single turbines, plus wake location and wake deficit behind the turbines.

Category: Corporate, Wind Energy