Variable Speed Wind Generators Participation in Primary Frequency Control

To maintain a power reserve to contribute to the primary frequency control with variable speed wind generators, two control strategies are analysed in this paper: a torque control strategy and a fuzzy logic based multivariable control strategy. The first and most simple strategy allows to maintain a regular reserve only when the wind turbine generator works at full load and needs the determination of a power reference value a priori or by the network manager. The second control strategy allows to overcome these limits without any wind speed measurement; it determines in real time the generator power reference value to maintain a fixed minimum reserve. The main result of this paper is to shown that it is possible to maintain a regular reserve on a large range of the wind speed. This reserve is still more regular when considering a wind farm owing to the wind speed dispersion. The performance of the proposed primary frequency control strategies is shown with the help of simulations by considering a wind farm including three wind generators.