Periodic and Non-Periodic Disturbance Accommodating Control of the Controls Advanced Research Turbine (CART)

Abstract

In this paper we investigate the use of Disturbance Accommodating Control (DAC) for periodic and non periodic control of two -bladed horizontal -axis wind turbines operat ing in Region III. R ealizab le DAC controller/estimator pair s are developed for use on an existing wind -turbine called the CART (Control s Advanced Research Turbine) located at the National Wind Testing Technology Center in Golden, CO. Previously, these designs were done using a gen eric model of the turbine . The DAC controller s developed are verified on a simulation of this CART model . T his model was created and validated in time -invariant control studies. Four different case s are presented: each with a different set of DOF’s. In each case, both a constant -gain and a periodic -gain Full -State Feed Back (FSFB) controller are developed. In addition to the FSFB controllers, a constant -gain and a periodic -gain realizable controller are developed . A total of 16 different simulations ha ve been run: 4 different controllers for each of the 4 cases. All simulations were run against a 5 DOF non -linear plant model. The results indicate that the periodic controllers are slightly better than the constant -gain controllers, but the less complic ated non -periodic controller s might be adequate for wind turbine applications. Also, the controllers with higher numbers of DOF’s did not perform any better than the simple controllers. However, the design of the non -periodic controller is based upon the periodic design; consequently periodic control is an essential part of the design methodology. NOMENCLATURE