Experimental Research On Wing-sail Slewing System Hydraulic Characteristics And Control Strategy

In recent years, with the running out of oil and increasing fuel oil price and intensive supervision of vessel exhaust emission for CO2 and NOx etc., the international shipping industry is forced to explore the new technology and new method of energy conservation and emission reduction. The wind energy is used by ship effectively and feasibly for a long time, thus many countries in the world have started to study and develop the wind-assisted ship.The wing-sail ship used wing style sail (wing-sail for short) usually adopt the hydraulic system as its slewing system. The slewing system should adjust and hold the wing-sail to a optimum angle accurately according to the wind condition. The slewing system should be safe, reliable and stable. So far, the study on the wing-sail slewing system is less and plain. It is significant to research on the wing-sail slewing system, especially for the experimental research.First of all, this thesis designs the wing-sail slewing experimental table and its hydraulic driving system schematic diagram based on the aerodynamics characteristic of a high lift-drag ratio multi-element wing-sail, referencing the form and principle of deck machinery on the ship. Secondly, the experimental table is assembled by analyzing the forces of the wing-sail and by calculating the gyroscopic moment and selecting main devices of hydraulic system. Thirdly, a series of rotating speed and pressure experimental features are achieved by doing experiments on the table. Finally, based on the experimental characteristics the wing-sail slewing primary control strategies are proposed and tested successfully, including the starting and braking control signal and its time domain, and the nonlinear compensation control method.Through practical and experimental verification, the wing-sail slewing hydraulic experimental table is assembled successfully. The experimental research results show: the experimental table can satisfy the requires of the wing-sail slewing process and the hydraulic driving system’s experimental characteristics; the random disturbing wind has important effect on the hydraulic system, and it is better to turn off the wing-sail when the wind is continuing reciprocating disturbing; the hydraulic system is working better at the starting and braking processes under the control of sine signal, and the optimum time domain is 2s for the staring and braking processes; the nonlinear compensation control strategy can improve the wing-sail slewing accuracy. The experimental researches on the wing-sail slewing hydraulic experimental table of the thesis provide a significant basis for the design of the wing-sail slewing system on the actual ship and the design of the slewing control strategy and arithmetic.