EXPERIMENTAL INVESTIGATION ON A CABIN-SUSPENDED CATAMARAN FOR WAVE ENERGY HARVESTING

Wave energy can be a significant factor in the progress towards a carbon-free society. This paper demonstrates the wave energy harvesting performance of a 1/2 scale cabin-suspended catamaran in regular head waves. The catamaran has a twinseater, the length is 3.28 m, and the width is 2.10 m. It consists of a suspended cabin, a suspension unit, and a twin-hull. One brushed DC Motor/Generator (M/G) coupled with one gearhead is set at each of the four corners of the cabin's deck. The shaft of the gearhead connects to a shaft of a pinion gear which meshes with a rack that is fixed on a hull through a ball joint. In this way, the vertical motion of the rack can be transferred into the rotational motion of the pinion causing the M/G generates electrical power. The power generation of the catamaran is experimentally investigated using a Maximum Power Point Tracking (MPPT) technique in a towing tank. Two control algorithms are developed: indirect MPPT and direct MPPT. It is found that the wave energy capture width ratio (CWR) obtained at the direct MPPT is approximately 11% higher than the indirect MPPT when their control parameters are having equal magnitude.