Maximum power tracking for a wind driven induction generator connected to a utility network

The paper proposes a simple control strategy that is applied to a grid connected wind driven system to facilitate harnessing maximum power. The principles of this strategy are demonstrated in a system which comprises a double-output induction generator driven by a variable-speed wind turbine. This strategy is based on controlling the slip power, which is extracted from the rotor circuits and fed to the grid though a rectifier/inverter branch. The firing angle of the inverter is used to control the slip power and, hence, the operating point. A mathematical model is presented to analyse the behaviour of the system and to demonstrate the capability of the proposed control strategy. An experiment has been conducted to verify the validity of the control strategy and the calculation methodology. A good agreement with the computed results has been obtained.