A Smart Wind Turbine Blade Using Distributed Plasma Actuators for Improved Performance

Abstract

This paper presents an innovative Plasma Aerodynamic Control E! ectors (PACE) concept for improved performance of wind turbines. The concept is aimed towards the design of “smart” wind turbine blades with integrated sensor-actuator-controller modules to improve the performance of wind turbines. The system will be designed to enhance energy capture, and reduce aerodynamic loading and noise by way of virtual aerodynamic shaping. Virtual shaping is the modification of the flow field around the surface by means of flow control (plasma actuators), which results in flow changes as if the geometry itself is altered. In e! ect the flow control scheme is giving the designer the capability to change the e! ective pitch distribution across the turbine blade as needed to control blade loading. The present concept is based on the use of surface-mountable, single dielectric barrier discharge (SDBD) plasma actuators on the turbine blades for increased energy capture and noise reduction. The system will allow continuous operation of wind turbines at near optimal conditions (as close as possible to the rated power coe cient) using a smart/adaptive PACE system in both steady and unsteady conditions (wind gusts, varying wind speeds, etc.), thereby ensuring safety and optimal power capture for electricity conversion. Experimental data and computational model results are presented that show the feasibility of using plasma flow actuators to control the aerodynamic characteristics of selected wind turbine airfoil sections. Two airfoil profiles designed for wind turbine applications were selected for this study. These were the S827 and the S822 profiles. The S827 airfoil was used to examine circulation control to increase the e! ective camber, and leading-edge separation control to increase Clmax. The S822 airfoil was used to demonstrate geometric changes that promote local flow separations that can be manipulated by plasma actuators to control lift. Both these approaches produced controlled changes in the lift coe cients on the airfoils that were equivalent to a trailing-edge flap or a leading-edge slat, but without conventional moving surfaces.