DYNAMICS MODEL OF MOVABLE BODY-TYPE WAVE ENERGY CONVERTER CONSIDERING TWO DIMENSIONAL MOTIONS OF THE FLOAT

Abstract

Dynamics model has been proposed for the float-counterweight type wave energy converter which takes into account the vertical and horizontal forces on the energy extracting float. The model consists of the equation of the generator, force balance at stationary free state, equation of the float motion in operation, and the equation for the driving pulley motion. Second order simultaneous differential equations for the vertical and horizontal displacement of the float have been obtained as the equations to be solved. Components of the flow force have been evaluated from the linear progressive wave theory. Examination of the model using the experimental data shows that the model underestimates the heaving and surge, overestimates the wire tension, and gives relatively good agreement to energy gain.