Advanced control methods for cross-flow turbines

B. Strom, S. L. Brunton, B. Polagye
2018 International marine energy journal  
Cross-flow turbines have a number of potential advantages for hydrokinetic energy applications. Two novel control schemes for improving cross-flow turbine energy conversion are introduced and demonstrated through scale experiments. The first aims to alter the local flow conditions on the blades through varying blade kinematics as a function of rotational position, thus increasing beneficial fluid forcing. An established method accomplishes this by oscillating the mounting angle of the blade.
more » ... le of the blade. Instead we proposed to vary the angular velocity of the blade as a function of azimuthal position. Optimizing this controller resulted in a 59% increase in turbine performance over standard controllers. The second control scheme operates an array of two turbines in a coordinated manner to take advantage of periodic wake structures. For a range of relative turbine positions, a parent controller maintains a constant blade position difference between turbines with the same angular velocity. For select positions, the array efficiency is shown to be greater than that of a single turbine. At the optimal position, coordinated control results in a 4% increase in array performance over uncoordinated operation. Finally, intracycle angular velocity and coordinated control schema are combined.
doi:10.36688/imej.1.129-138 fatcat:2lnuep5xo5azxnv66rtb7ktc7e