Research On Vibration And Shock Response Characteristics Of Marine Relay

As the most basic electronic component in ships,relay for ships plays an important role in ship control system.In order to get the vibration and shock response characteristics of marine relays on rivers and seas,the vibration and shock response characteristics of the contact spring system which is most susceptible to environmental interference in relays are studied in depth.Firstly,the development of ships and the research status of relays in China in recent years were introduced,the failure modes and reliability requirements of relays were expounded,and the mechanical model of relay reed was established.After constructing the relay finite element model,the modal analysis of the relay finite element model with initial force was carried out,and the natural frequency and mode shape of the contact spring system were obtained.According to the results of modal analysis,the vibration simulation analysis of the contact spring system was carried out,and the contact force change curve between relay contacts,the stress curve at the root of the reed and the displacement curve at the end of the reed were obtained under different frequency vibration loads.Through the harmonic response analysis of the contact spring system,the response changes of the contact spring system in the frequency of 1-600 Hz were obtained,it is concluded that the working environment of ship relay should be as far away from the natural frequency of contact spring system as possible to reduce the negative impact caused by resonance phenomenon.Secondly,the shock simulation of relay contact spring system under different working conditions was carried out,and the shock response characteristics of relay contact spring system under different working conditions were obtained.It is found that shock may cause short-time disconnection of contacts and accelerate the aging of springs,and it is concluded that increasing the area of static contacts can effectively improve the shock resistance of relay contact spring system.A variety of time-domain shock loads were designed,and the influence laws of maximum acceleration response,pseudo-velocity response,maximum relative displacement response and shock response of relay contact spring system were obtained by simulation analysis.By changing the delay time of negative wave delay,the influence of negative wave delay phenomenon on the shock response characteristics and working reliability of relay contact spring system was discussed.Then,the vibration and shock tests of relay were carried out,and the natural frequency of the relay and the contact voltage curves of the relay under different shock conditions were obtained.The experimental data were processed and compared with the simulation data,it is found that the change trend of relay endurance response characteristics obtained by simulation and test is consistent,which indicates that simulation method used are correct.Finally,the specific position of the limiter was determined,and the vibration and shock simulation of relay model with limiter under contact mode 2 was carried out under various working conditions,and the vibration response and shock response of relay model with limiter were obtained.Compared with two relay models with and without limiter,by observing the value of contact force between the two contacts and the change trend of stress at the root of the reed,it is concluded that this kind of limiter device can effectively improve the anti-vibration and anti-shock ability of marine relay.The research can provide an important reference for the design and improvement of antivibration and anti-shock of marine relay,and give a new idea for the research of contact reliability of marine relay.