Adaptive Control of In-Stream Ocean Current Turbines for Load Reduction

The ocean currents off Florida are a renewable and
energy dense resource capable of providing Florida
with about 25% of its electricity needs. This current
is strongest at the sea surface and decreases
in strength with depth such that the individual rotor
blades on ocean current turbines (OCT) deployed to
harness this resource will operate in stronger currents
when positioned vertically upwards than when vertically
downwards. This current shear will induce cyclic
loadings on the rotor blades unless active control is
used to reduce these load variations. A direct adaptive
individual blade pitch controller is implemented
into a numerical model simulating an OCT operating
in the Gulf Stream. The adaptive controller is analyzed
with the OCT simulated in both stationary and
moored configurations. The results concluded that
the IBP controller reduced the amplitude of the loads
in the stationary and moored simulations by 91.18%
and 92.3%, respectively.