舰船浮筏混合隔振系统建模及约束输出控制策略

摘要

针对舰船内部动力机组浮筏系统低频隔振效果不佳的问题，提出有源前馈控制解决方案。建立由多向扰动振源、分布参数主被动一体式隔振器、中间柔性筏体及弹性安装基础组成的浮筏混合隔振系统结构声传递广义数理模型。基于导纳矩阵理论，定量考虑实际作动器输出的阈值限制，给出浮筏混合隔振系统动态传递特性统一数学模型。从声振能传递与控制角度揭示系统耦合振动机理并给出浮筏系统隔振设计遵循准则。研究表明，力矩激励在浮筏隔振系统能量传输中扮演重要角色，应尽量减少力矩扰动所致能量注入；中间筏体结构柔性及与隔振器内共振的耦合交互作用使中高频段系统隔振性能恶化；全主动控制策略可结合上、下层主动控制策略在低、中高频段的振动控制优势，能实现宽频域内声振能控制最优化。%In order to improve the low-frequency performance of floating raft systems conventionally used in marine ships,a feedforward active control solution was proposed.An analytical model consisting of complex excitations, distributed parameter isolators,a flexible floating raft and a non-rigid foundation was established.Considering the output threshold of actual actuators,a general mathematic description of the dynamic transfer characteristics of the overall system was given by using the mobility matrix approach.It is shown that moment excitations play an important role in the vibration transfer process.Coupling interactions between the elastic raft and distribution parameter isolators can lead to a deterioration of performance in the high-frequency domain.The upper active control strategy can achieve good effect at rigid-body modal frequencies,and the prominent advantage of the lower active control strategy is mainly reflected in higher frequency band.However,the full active control strategy can realize the optimal control of vibra-acoustic power in broadband domain.