| With sonar system constantly improve markedly improved detection ability,especially for low frequency noise of ship line of low frequency vibration greatly reduces the acoustic stealth performance of ships,the active vibration control of low frequency vibration has good control effect,into the ship piping vibration control for further weaken line low frequency vibration has profound practical significance.As the active execution structure of pipeline vibration active control system,electromagnetic actuator directly acts on the controlled pipeline,and its performance will directly affect the control effect of pipeline low frequency vibration.Based on the design of a new electromagnetic actuator,this paper studies the magnetic circuit structure parameter optimization,engineering prototype manufacturing and performance testing,and evaluates the vibration reduction effect of electromagnetic actuator prototype applied to pipeline low-frequency vibration effectively.The main research contents of this paper are as follows:Firstly,two different types of electromagnetic actuators are compared,and a moving magnetic electromagnetic actuator is designed for pipeline low-frequency vibration control,and its working principle is analyzed.The dynamic physical model of electromagnetic actuator is established,and the influencing factors of its output force are analyzed.The results show that increasing the mass of actuator and increasing the force constant can effectively increase the output force of electromagnetic actuator.Simulation analysis is made on two magnetization modes of ring permanent magnet,and the distribution of magnetic induction intensity of magnetic circuit air gap under different magnetization modes is explored,and the axial magnetization mode is determined for permanent magnet.A magnetic circuit structure model with two permanent magnets in series was designed,and the average magnetic induction intensity at the magnetic circuit air gap was taken as the sensitivity evaluation index.Secondly,the experimental design method was introduced into the optimization analysis of magnetic circuit structure of electromagnetic actuator.The sensitivity of single structural parameter of magnetic circuit to evaluation index was analyzed by all-factor experimental design method,and the sensitivity of magnetic circuit structural parameter to evaluation index was analyzed by orthogonal experimental design method under coupling effect.Magnetic circuit was built based on the response surface analysis,the average air-gap magnetic induction intensity of the second order polynomial response surface agent model,and through the genetic algorithm to optimize the main structural parameters of magnetic circuit,the results show that after genetic algorithm to optimize the magnetic circuit average air-gap magnetic induction intensity compared to the initial design value increased by60.38%,up 25% compared with the experimental design method.Finally,the machining of the electromagnetic actuator prototype is completed and its performance is tested.The results show that the dynamic output force of the prototype can still reach 250 N at 150 Hz,and the output force performance is good.When the electromagnetic actuator works at a lower frequency,the distortion is relatively large.With the increase of the frequency,the distortion gradually decreases,but the overall distortion is controlled within 5%,and the prototype of the electromagnetic actuator meets the design requirements.In order to verify whether the electromagnetic actuator prototype can effectively suppress pipeline vibration and achieve ideal vibration reduction effect,the pipeline vibration active control test is carried out.The results show that the vibration reduction amount of measuring point 1 at the fundamental frequency of 48 Hz is 22.8d B,and that at the double frequency of 96 Hz is 12.9d B.The vibration reduction of measuring point 2 at the base frequency of 48 Hz is23.7d B,and the vibration reduction of measuring point 2 at 96 Hz is 10.2d B.Both measuring points of water outlet pipeline have achieved good control effect.The electromagnetic actuator designed can be applied to active control of pipeline vibration and effectively weaken the low-frequency vibration of pipeline. |
