Control of Variable Speed Wind Energy Conversion Systems by a Discrete-time Sliding Mode Approach

This paper presents a discrete-time variable-structure-based control designed for a variable speed wind energy conversion system based on a permanent magnet synchronous generator. A cascade control scheme is proposed to obtain the maximum power efficiency. The analysis of the control stability is given and the ultimate boundedness of the speed tracking error is proved. Reported numerical simulations show that the proposed controller enhances the overall performance obtaining the maximum power efficiency and it is robust under variable operating conditions and in the presence of disturbances affecting the system.