In order to effectively control the low-frequency vibration of ship machinery, an active-passive hybrid vibration isolator based on multi-line spectrum adaptive control is proposed. Firstly, the structure of this hybrid isolator is designed, and a two-degree-of-freedom vibration isolation system dynamic model is established. Based on the proposed model, the control force requirements of the vibration isolation system in different damping forces are analyzed. Then, the improved wavelet packet decomposition algorithm and Hartley transform are introduced to the FxLMS (filter-x least mean square) algorithm. A multi-line spectrum adaptive control algorithm with time-delay compensation and fast convergence speed is put forward. Finally, experimental results demonstrate that the active-passive hybrid vibration isolator can effectively reduce the low-frequency line spectrum vibration energy. Experiments have shown that the multi-line spectrum adaptive control algorithm has a better control effect than the traditional FxLMS algorithm.

Low-frequency line spectrum,Active-passive hybrid vibration isolator,Adaptive Control,FxLMS algorithm