Research On System Design And Control Method Of Passive Anti-roll Tank

The anti-rolling tank is one of the most popular used stabilizing equipments, which fits for ships working at each speed such as passenger and train ferry, roll-off vessel, research and exploration vessel and so on in particular. The anti-roll tanks equipped on ships, whatever they are passive or passive controlled, are mostly u-shaped. The u-shaped anti-roll tank, which is easily designed and controlled, can require effective roll stabilization.In this paper, tank system design, control method of passive controlled tank were investigated to improve the tank's stabilization ability.According to the Lagrange dynamics equation of motion, a mathematical model of the ship- passive anti-roll-tank system was developed. And ship rolling frequency response function with two U-tube anti-roll tanks of different natural frequencies was developed. Design method of U-shaped anti-rolling tank system was established, and procedure of scale design for tank was summarized. An innovation selecting the natural frequency of passive tank was put forward according to sea condition and ship. The influence of tank vertical location within the ship was studied. Causes of formation of tank damping and motion state of water in tank were studied, calculation formula of the U-tube tank damping and design method of tank damping configuration were given.Control facility and conventional control methods were introduced. After analyzing the control principle of anti-roll tank, a novel control strategy was put forward based on method of torque opponency. New strategy was studied by simulation compared to conventional methods.A system was designed for a RoRo ship, and the effect of ship separately equipped double-tank system and single-tank system was tested through digital simulation.The simulation results show that ship installed double-tank system has more effective stabilization in wider natural frequently changing of ship and more complex sailing condition, compared to ship installed single-tank system. According to the simulation results, each conventional control method of passive controlled tank has both advantage and disadvantage, and the novel control strategy has good performance. Better effect "will be achieved when the algorithm is improved in further study.