Hydrodynamic characteristics of tensile floating island-type offshore floating photovoltaic array

In this study, an array composed of eight tensile floating island-type offshore floating photovoltaic (FPV) platforms was investigated. Wave-tank model tests were conducted to examine its hydrodynamic characteristics under different irregular wave conditions. Taking the prototype installed capacity of 2 MW as an example, a 1:40 scale model was tested in a wave tank using wave data from the Bohai Sea. The motion responses of pitch, roll, and surge acceleration were analyzed in both time and frequency domains. The results show that: (1) The motion response of the wave ward-side floating structures is the largest, whereas the central structures exhibit minimal motion due to array constraints and shielding effects. (2) The FPVs array exhibits significant phase differences between units, indicating complex nonlinear interactions. (3) The response is more sensitive to wave height than to spectral peak period, and long-period waves (6–7 s) induce the largest motion. (4) Frequency-domain analysis indicates that wave ward-side structures receive the highest energy input, central structures are the most stable, and leeward-side structures experience strong responses with high-frequency components. (5) Under conditions of wave heights greater than 0.075 m and spectral peak periods above 0.949 s, surge acceleration of some floating structures exceeds 0.5 g, suggesting the need to limit array operation to ensure safety. These findings provide valuable guidance for the design, optimization, and safe operation of tensile floating island-type offshore FPV arrays.