A UTILITY INTERACTIVE WIND ENERGY-CONVERSION SCHEME WITH AN ASYNCHRONOUS DC LINK USING A SUPPLEMENTARY CONTROL LOOP

The paper presents modelling, simulation and experimental verification of a utility interactive wind energy conversion scheme [WECS] with an asynchronous link comprised of a diode bridge rectifier and a line co mmutated inverter. The control objective is to track and extract maxim um power to the utility. wind energy system [WSE] and transfer this po wer to the utility. This is achieved by controlling the firing delay a ngle of the inverter. Since the diode bridge rectifier has no control on the dc link voltage, a supplementary control loop is used to limit the voltage within a preset voltage threshold. The proposed scheme for regulating the flow of power through the dc link ensures reduced reac tive power burden on the self-excitation capacitor banks and better ut ilisation of available wind energy, while limiting the dc link voltage within a preset voltage threshold. The simulated results are experime ntally verified and found to give good power tracking performance.