Analysis Of Electromagnetic Vibration And Noise Characteristics Of Power Equipment And Research On Noise Reduction

The noise problem of power transformers is gradually attracting attention,especially because the harmonics introduced by nonlinear loads in the power grid and new energy industries aggravate the noise and vibration.Changes in vibration and noise will affect the surrounding environment and the service life of power transformers.In order to explore effective noise reduction methods,it is necessary to take an analysis of the causes of vibration of electrical equipment.This paper conducts numerical simulation analysis and experimental research on vibration and noise of power transformers,and tests of active noise reduction methods,mainly from the following aspects:(1)In order to obtain the magnetic characteristic parameters required for the numerical calculation of laminated electromagnetic vibration,this paper adopted the MST500 magnetic characteristic measurement system device that conforms to the IEC international standard,and developed the magnetization characteristics and magnetostrictive characteristics of iron core silicon steel sheets under different harmonics.Based on the measurement data,numerical calculation and analysis of electromagnetic vibration of power transformers are carried out.(2)Based on the measured magnetic characteristic data,a three-dimensional numerical weak coupling calculation model of the target power transformer is established to explore the service magnetic characteristics,electromagnetic vibration and sound field distribution of the power transformer under harmonic excitation;considering the iron core magnetostrictive effect,the magnetic field,mechanical field,and sound field of power transformer are calculated under harmonic excitation,and the results of magnetic field,sound field,and iron core vibration are obtained,and compared with the calculation results of power frequency sinusoidal excitation,the influence of harmonic input on the electromagnetic vibration of iron core is summarized.(3)Firstly adopt active noise reduction method to judge the noise reduction effect of the model;the device models are selected to build the active noise reduction hardware system;The main control algorithm program is written,and the function of each unit is modularized;The overall system is coordinated to optimize the efficiency of the system.(4)Test experiments for the target power transformer is done including measure the vibration displacement and acceleration of the measured point of the laminated core under specific working conditions to verify the accuracy of the numerical calculation results;research on the sound field distribution around the power transformer before and after the active noise reduction to explore the optimal noise reduction area and the optimal active noise reduction plan dimensionally.This article focuses on active noise reduction methods and explores the noise reduction effects of this method.The research content is beneficial to the accumulation of engineering practice experience in the field of noise reduction,and is of great significance to further propose effective noise reduction methods.