An Optimization Framework for Load and Power Distribution in Wind Farms: Low Wind Speed

Abstract In this paper, an optimization approach has been developed for wind farms such that the reference signals for each wind turbine is produced and load reduction on each of them is taken into account. The proposed approach is based on a spatially discrete model of the farm which provides wake information and delivers an approximation of wind speed all over the farm. The farm controller can affect the generated wake of each wind turbine either by changing the pitch angle and power reference or rotor speed reference signals, and this is the motivation for the proposed optimization method for a farm. The problem of determining the reference signals for wind turbine controllers is considered separately for low and high wind speed regions. However, because of the complexity of the high wind speed scenario formulated with this approach, only the problem in low wind speed has been scrutinized. Accordingly, in low wind speed, the reference signals for rotor speed are adjusted, taking the trade-off between power maximization and load minimization into account.

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