Optimal Control of a Variable-Speed Wind Energy Conversion System: A New Approach

The operation of wind energy conversion systems mainly deals with variable and unpredictable wind regimes resulting in variable power efficiency. In addition, nowadays with the presence of high penetration level of wind farms integrated to power systems, stability and power quality problems might be addressed, when a disturbance event occurs. These challenges are worsened with significant degree of nonlinearity, which leads to complex control. In this research despite common sophisticated methods, a novel control strategy based on linear controllers were employed to guarantee sufficient damping and performance once it undergoes the test including power regulation, wind speed variation and voltage sag and swell. Furthermore, a new optimal linearisation technique was proposed to improve accuracy in comparison with conventional linearisation methods. The simulation results on a full variable-speed benchmark system show the effectiveness of the opimised methods in the fulfilment of the control requirements within an acceptable time in terms of relevant control indices.