Optimal Control of Wave Energy Converters

The control logic of a Wave Energy Converter (WECs) usually aims to increase the energy converted from waves. For optimal energy conversion, most WEC control methods require reactive power; that is a power flow from the WEC to the ocean, at times, in order to increase the overall harvested energy over a period of time. The power take off (PTO) unit that has the capability of providing reactive power is usually expensive and complex. In this work, an optimal control analysis is presented in which the objective of the optimal control problem is to maximize the harvested energy while constraining the power flow to be only in the positive direction; that is adding a constraint of no reactive power. The optimal control derivation is presented for the case of a solo WEC. Low fidelity numerical simulations are presented comparing the proposed control to the known Bang-Bang (BB) control and the Bang-Singular-Bang (BSB) control.