Design and Optimization of PV Power Supply System for Marine Buoys

Abstract

Marine buoys need to operate in high sea areas far from land for a long time. Therefore, how to provide a long-term power supply for the buoy system is critical to be addressed. Photovoltaic (PV) power supply systems are the most commonly used power supply method for marine buoys. Due to the limitations of the buoy structure and considering the rotation of the buoy in the ocean, most of the PV modules are placed in a four-sided enclosure. The output performance of the PV power supply system in this placement is affected by the tilt angle produced by waves. However, there are few relevant studies on the actual power generation performance of PV power supply systems for marine buoys, and there is a lack of methods for power generation performance analysis. In order to meet the power requirements of the marine buoy, a large design margin must be left. It increases the cost of marine buoys. In this paper, second-order Stokes waves are used to simulate waves of different levels by varying the wave height and frequency. The motion characteristics of the marine buoy are analyzed using ANSYS-AQWA under calm-rippled, smooth, slight, and moderate conditions. Combined with the tilted surface irradiance calculation model to get the variation law of solar radiation of PV modules under dynamic conditions, the effect of different tilt angle PV modules on the output of PV system under dynamic conditions was also studied. The experiments show that for every 5° increase in the tilt angle of the PV modules the output power of the system decreases by 3% on average. As the tilt angle of the PV modules increases, the impact on the system output performance is more pronounced. The output power decreased by 69.5% when the PV modules were tilted at an angle of 90°, and the PV system electrical parameters were similarly affected. By comparing the influence of different tilt angles on the power supply performance of PV modules, we optimize the design of the PV power supply system of the buoy. This enables the designers to maximize the use of limited area and space while reducing the cost and extending the power supply time and service life of the buoy.