Research On Control Strategy Of The Controlled Passively Anti-rolling Tank

The anti-rolling tank is one of the widely used stabilizers in the world, and it fits for ships working at zero speed or low speed , whose characters are simple structure, low cost and easy to maintain. The anti-rolling tanks have three types including passive anti-rolling, controlled passively anti-rolling tank and active anti-rolling tank. The controlled passively anti-rolling tank has high performance, and it can adjust the water oscillation period through the valves in the upper of side tank in order to adapt the roll period. Thus the controlled passively anti-rolling has favorable effect in the any states. It has been proved that this kind of tank is applicable of multifold boats, which not only reduces the roll angle and the heel angle, but also improves the efficient and fall the transport cost. The controlled passively anti-rolling tank can elevate the comfort and safe of the boats.The paper is based on the item the anti-rolling tank test setup among the school "211" key construction projects. The control method of the controlled passively anti-rolling tank is mainly investigated, and test about the controlled passively anti-rolling tank is researched.The research achievement on the academic research and model test of anti-rolling tank at home and abroad is roughly described first by a lot of documents. Aiming at the controlled passively anti-rolling tank, the main subjects are drafted.As the basis of study in the last chapters, the operational principle of passive anti-rolling tank and controlled passively anti-rolling tank is described. We also discuss the configuration of valves, and an innovation selecting the natural frequency of controlled passive anti-rolling is put forward.According to Lagrange dynamics equation of motion, a mathematical model of the ship-controlled passively anti-rolling tank system is developed. We take advantage of impulse response method to solve the mathematical model. In the light of the signals of roll angle and water level, we can control the air valve, and use this control method to simulate the controlled passively anti-rolling tank. Simulationresults indicate that this control strategy is feasible. The controlled passively anti-rolling tank can work in the wide frequency range.In addition, we should have not only the theoretical research on the controlled passively anti-rolling tanks, but also carry through performance test on them, which is necessary to study performance of the anti-rolling tank and predict ship's rolling motion. The monitoring system of the controlled passively anti-rolling tank model performance takes charge of control and regular service of anti-rolling tank. Accomplishing the hardware design and software programmed of tank control, data acquisition, we process the model test of the controlled passively anti-rolling tank. According to signals of the roll angle and water level, the control system output signals to open or close the valves, and achieve some stabilized effects.