Utility Integrated Variable Speed Wind Energy Conversion System Using Innovation Sequence based Modified Kalman Type Estimator and Improved Robust Control Technique

A utility integrated wind energy conversion system (WECS) encounters challenges in regulating the power flow of the grid and peak wind power extraction from the variable speed wind turbine. To take care of these challenges, this paper proposes an innovation sequence based modified Kalman type estimator (ISMKE) based control for the utility side converter (USC) and an improved robust speed control technique with disturbance rejection capability for the wind turbine side converter (WTSC). The proposed ISMKE estimates fundamental positive sequence component from harmonics contaminated nonlinear load current to generate sinusoidal reference grid currents. Estimation of the harmonics and disturbance free positive sequence load currents, is performed for achieving good grid synchronization and load compensation. The USC with proposed control technique is proficient of dealing with the power quality issues such as load unbalancing, power factor correction, harmonics elimination and load compensation. Moreover, it effectively regulates the active power flow from the WECS to the grid. The WTSC uses field oriented control (FOC) that controls the q-axis current, where the reference q-axis current is generated by using the proposed improved robust sliding mode speed control technique that provides improved performance against model uncertainties and external disturbances.