Experimental Research On Active Control Of Longitudinal Vibration Of Shafting

Ship vibration and noise seriously affect the comfort of the ship and the reliability of the operation of electronic equipment.An important cause of vibration is the thrust pulsation of the propeller.This kind of thrust pulsation is transmitted through the shaft,thrust bearing,and base to the shell and causes vibration So it is feasible to control the vibration of the system by controlling the longitudinal vibration of the shafting system.The most common methods are passive vibration damping,Less active damping and mostly theoretical analysis,Less active control based on piezoelectric materials.By referring to the existing ship propulsion shafting device and designing piezoelectric actuators in combination with stacked piezoelectric materials,a longitudinal vibration active control test platform is built for experimental research.The specific content includes the construction process of the platform,the characteristics of the longitudinal vibration of the shafting system,the vibration characteristics of the stacked piezoelectric materials,and the PID control algorithm.Therefore,this paper explores the application of piezoelectric materials in the active control of longitudinal vibration in shafting systems.The main content is as follows:First of all,this article systematically summarizes the relevant references of the research project and understands the research status of the project at home and abroad,so as to have a general understanding of the research project.Based on this,using the distributed parameter method and lumped mass method to model the axis Understand the longitudinal vibration characteristics of the shaft to provide theoretical guidance for the next longitudinal vibration control experiment.Then use Labview software to compile the control program based on PID control algorithm.The acceleration value is the control object.The data measured by IEPE accelerometer is imported into the control program,and the difference between the calculation and the set value is calculated.Then,the size of the control voltage is calculated by PID algorithm and output from the PXI-6733 analog output board to the piezoelectric actuator for active damping.The test results show that the longitudinal vibration of the test platform can be reduced by 12.46% and 27.38% when the constant frequency 153 HZ and 205 HZ excitation are performed.It can be seen that the active control of longitudinal vibration based on the piezoelectric material has a certain effect,but at the same time it needs further improvement.In the end,the whole work of the project is summarized,and the deficiencies in it are analyzed,and the work to be carried out in the future is anticipated.