Optimal Cable Configurations for Passive Dynamic Control of Compliant Towers

Abstract

Whether in storm or normal seas, the ideal offshore cable-stayed compliant tower moves in harmony with the wind and waves. A properly tuned cable configuration is the key to controlled dynamic response. Formulated here are a nonlinear dynamic model involving wind, wave, current, tower, and cable interactions and a cable optimization algorithm. The objective function, the rms tower rotation, is minimized subject to appropriate constraints involving compatible system geometries and loads, as well as bounds on the platform level accelerations needed for human comfort. Tower motion is limited to a plane.