Design And Experimental Study Of Semi-active Electromagnetic Vibration Absorber

The semi-active vibration absorber is currently a research focus in the field of vibrationcontrol. The electromagnetic semi-active vibration absorber studied in this paper can changeits natural frequency by adjusting the excitation current, thereby achieving tracking control ofexcitation frequency within a certain frequency band. The main content of this paper is asfollows:1. Appling electromagnetic field theory to make a theoretical research of the vibrationabsorber’s interdental air-gap permeance and axial electromagnetic force, obtained themethod for determining the optimal size of the electromagnetic semi-active vibration absorber,and combined with electromagnetic semi-active vibration absorber’s working principle andperformance indicators proposed the method and steps to design an electromagneticsemi-active vibration absorber.2. According to the actual situation of the controlled main vibration system devised anew type of electromagnetic semi-active vibration absorber, which features asymmetric teeth,built-in coil, etc.; used electromagnetic finite-element analysis software Maxwell Ansoft tomake optimization analysis of the various dimensions of the vibration absorber’s magneticcircuit and ultimately determined the optimal size; and then carried out test of static stiffnesscharacteristics, test of working frequency characteristics and test of damping ratiocharacteristics on the processed vibration absorber prototype to obtain its damping ratio of0.029, and that within the working current range of0~2.5A, its adjustable range of staticstiffness was44974~1207544N/m, adjustable range of working frequency16.5~82.5Hz;the simulation and experimental results were basically the same, jointly verifying the betterperformance of the new type of semi-active electromagnetic vibration absorber, providing thebasis and reference for the future design of electromagnetic actuator.3. Carring out a bench-based vibration absorption experiment on the electromagneticsemi-active vibration absorber prototype: within the vibration absorber’s range of workingfrequency used single frequency sinusoidal excitation signal to excite the bench, and thenused the vibration absorber to absorb the vibration of the bench, and found that exceptindividual points the vibration absorber had a certain vibration absorbing effect on each testpoint of each frequency, especially at62.5Hz or above the damping effect was5dB or more on basically each frequency and on some frequency points even reached more than30dB,which effectively took control of the vibration of the entire test bench and the vibrationreached the base via isolator and verified the actual working performance of the vibrationabsorber.