基于最佳相位匹配的减摇鳍低航速控制策略

为了满足工程船舶对低航速下减摇的需求,提高船舶在锚泊和低航速下的耐波性,提出减摇鳍在低航速下的控制策略,重点针对低航速下升力与鳍角之间相位关系对航速十分敏感的问题和船舶横摇模型的不确定性问题进行研究.通过数值迭代解决低航速下升力相位对航速的敏感性和升力与鳍角的非线性关系问题,相位调节器可以克服航速测量误差的影响,保证最佳的相位匹配;利用分数阶鲁棒控制器保证模型参数变化时整个系统的控制性能.对所设计的控制策略进行数值仿真,仿真数据表明,在随机海洋环境干扰下,减摇鳍可以获得满意的低航速减摇能力.进行船模水池试验,试验结果也表明,所设计的控制策略可以使减摇鳍在锚泊和低航速下产生满意的减摇效果.

Best phase matching based control strategy for ship stabilizer at low speed

In order to stabilize the engineering ships under low speed and improve its seakeeping at anchor and low speed, the control strategy of a fin stabilizer at low speed is proposed. Two main problems, such as the phase between the fin angle and the lift is very sensitive at low speed and the ship roll model has uncertainty, are studied. A numerical iterative method is introduced to solve the phase sensitivity at low speed and the nonlinear relationship between the lift and the fin angle. The phase adjuster can overcome the influence of speed measurement error to ensure the best phase matching. A fractional order robust controller is used to ensure the control performance of the fin stabilizer system when the model parameters are varying. A numerically simulate of the proposed control strategy is done, and the simulation data show that under the random ocean environment disturbance, the fin stabilizer can obtain satisfactory stabilizing effect under low speed. Finally, ship model testes in towing tank are carried out, and the test results also show that the designed control strategy can provide satisfactory anti-rolling effect at anchor and low speed.