Concert - Control and uncertainties in real-time power curves of offshore wind power plants

Gregor Giebel, Tuhfe Göçmen, Jonas Kazda, Nicolaos Cutululis, Torben Juul Larsen, Christos Galinos
DTU Wind Energy, Risĝ, Denmark


Modern wind farms need to be grid-friendly in times where wind power produces a sizeable amount of the total electricity in the grid. Their controllability plays a crucial role, to be downregulated when there is too much power in the grid, or to provide some upregulation potential when there is danger of too little power in the grid. For the latter case, the calculation of the possible reserve power needs an accurate assessment of the power available from the wind power plant given the current wind conditions. During the last 4 years, the ForskEL PossPOW project developed the necessary real-time power curve for offshore wind power plants, and verified it with some experiments. The follow-up project Concert now enhances the PossPOW real-time power curve with the impact on loads, with an uncertainty calculation, and with additional experiments. Concert also develops an optimal control strategy to distribute the set-points on the turbines with regard to the total power and loads.


The real-time power curve algorithm PossPOW will be the basis for a calculation of the local wind speed and turbulence at the turbine positions within a downregulated wind farm. The improvements will be tested with dedicated experiments at offshore wind power plants of project partner Vattenfall, ideally containing wind turbines of project partner Siemens Wind Power. The convolution of the power forecasts with the algorithm's uncertainty is investigated (see Göçmen et al on this conference). Additionally, Concert develops a wind farm control algorithm for improved power or reduced loads (see Kazda et al on this conference). For the fatigue load estimations the Dynamic Wake Meandering method is extended. Finally, the improved wind power plant control will be tested at Vattenfall's trading office in Sweden.


The PossPOW algorithm uses 3 input signals from the individual turbine SCADA to estimate the local wind speed and turbulence intensity. The uncertainty module processes the differences in the error distributions between the reported statistical AEP calculations and real-time wind farm power. Eventually, it is targeted to combine the short-term forecasting uncertainty with online results to provide a platform for the market players to assess the risk.
The developed wind farm control operates in two modes: total power maximisation and total power reference following operation while reducing fatigue loading. The developed controller is first tested in simulation tools and later potentially a full-scale wind farm. The loads database covers the most dominating inflow conditions and is a very fast method usable for online predictions.


The poster presents a new Danish national project, enhancing the PossPOW real-time power curve with a full uncertainty calculation, with a load parameterisation amenable for real-time control purposes, and with optimal control for maximum power extraction or minimum loads. The results will be tested at operating offshore wind farms and for trading on the electricity exchange.
Funding from the Danish programme ForskEL is acknowledged.


The PossPOW project has gotten a successor, Concert, enhancing the PossPOW real-time power curve in several aspects.
Aim of Concert is to distribute set-points within a wind farms for optimal power production, load reduction or minimisation of uncertainty. The outcome of Concert will be tested on a Vattenfall operational wind farm.