Optimal analysis on low frequency line spectrum sound control of power equipment using dynamic vibration absorber

Abstract

As generated by alternating current with the frequency of 50 Hz, the noise characteristics of power equipment reveal to be low frequency and line spectrum. The paper proposed a method to reduce the noise of the power equipment by installing dynamic vibration absorber (DVA) on the surface of it. The coupling between the attached DVA and the equipment may lead to undesirable frequency shift of the DVA itself, which will diminish the noise suppression effect of the whole system. The traditional passive DVA design method does not consider the effect of dynamic coupling. To solve this problem, global demodulation algorithm is applied to analyze the optimal parameters of DVA, which is integrated in the model of power equipment, to get the lowest single frequency radiated sound power level (SPL) of the equipment. The finite element model is established to verify the noise reduction optimal effect. The results show that the noise reduction effect of the optimized system is significantly improved compared with that using the classical parameter setting. The research can provide references for noise reduction optimization of power equipment in the future.