An Electrical Stall Control Algorithm for Small-Scale Wind Generation System using Aerodynamic Observer

In a small-scale fixed-pitch variable-speed wind generation system, the power production has to adapt to various wind conditions by varying its rotation speed to achieve the maximum power extraction. However, this maximum power extraction behavior may result to over-rated operation of the system in high wind speed regions, where wind speed to the system is higher than its rated wind speed. Therefore, the power production of the system has to be regulated by certain stall control algorithm within system constraints in order to achieve long term operation in high wind speed regions. In this paper, a novel electrical stall control algorithm using an aerodynamic observer is proposed for small-scale wind generation systems to perform power curtailment and stall regulation of the wind turbine when operating in high wind speed conditions. By integrating of the aerodynamic torque observer and the additional stall control loop into the system, the operation of the wind turbine can be estimated and controlled to achieve desired stall regulation. Detailed control system analysis and simulation results have been presented in this paper to demonstrate the effectiveness of the proposed algorithm.