Research On Active Vibration Reduction For A Main Power Of A Yacht

As a modern high-end leisure consumer goods,the sound and vibration comfort requirement of a yacht is more strict compared with general civilian ship.In order to meet the comfort requirement,strict vibration and noise reduction design is needed,including vibration control design for yacht power equipment,and noise reduction design for major noise sources.The vibration control of the main vibration source of the yacht is of great significance to improve the comfort of the yacht.Passive vibration isolation can achieve good performance for medium and high frequency vibration,but not for low frequency vibration.So it is important to take other methods to suppress low frequency vibration into account.In this paper,the vibration problem of ‘Changdanghu’ yacht is focused on,and an active vibration reduction system is designed to solve the problem.Active actuators are installed on the yacht engine,and vibrations generated by the actuator will counteract the vibration generated by the yacht engine.The electromagnetic inertial actuator is selected,and the appropriate parameters are designed to meet the control system demand,the multi-channel filtered x-LMS algorithm is chosen as the control strategy to realize the goal of active vibration reduction design for the yacht.Firstly,the vibration characteristics of the yacht are analyzed.The main vibration source of the yacht is determined from the measurement of forced vibration response of cabins.The vibration characteristics of main vibration source are analyzed,and the transfer functions of the possible actuating installation structures are measured for determining the vibration transmission characteristics from source to the hull.Secondly,according to the results of yacht vibration characteristics analysis,the active reduction system is designed,including the design of electromagnetic inertial actuator,the selection of control algorithm,as well as the hardware equipments and installation.Thirdly,simulation of the active vibration reduction system is carried on to determine the control frequency band and control strategy.Finally,the experimental investigation of the active vibration reduction system is carried on to verify the control effect on a real yacht.The experiment results show that the system can reduce the vibration level at the control frequency.