Research On The Magnetic Properties Of Amorphous Alloys And The Magnetically Induced Vibration Of Iron Cores

The amorphous alloy material has lower unit loss,which can effectively reduce the no-load loss of transformer compared with the traditional electrical steel sheet.However,due to the large magnetostrictive coefficient of amorphous alloy material,the noise caused by electromagnetic vibration of the core during the operation of transformer seriously affects people's living environment.In order to effectively reduce the electromagnetic vibration of amorphous alloy transformer during operation,it is of great significance to accurately predict and analyze the vibration of transformer products in the production design stage.Since the amorphous alloy transformer core is mainly made of rolled strip,the magnetic properties of the amorphous alloy strip and the annealed amorphous core are measured first,and the effect of annealing treatment on the magnetic properties of the amorphous alloy is analyzed.On this basis,the magnetic vibration of the core of the small-scale amorphous prototype is calculated,and the vibration of the core of the prototype is measured and compared with the numerical calculation results.In order to study the influence of local clamping force on the amorphous alloy coil core,the magnetic properties and vibration of the core under different clamping forces were measured,and the numerical calculation model was established to analyze the vibration measurement results of the prototype.The main contents of this paper are as follows:(1)Based on the principle of laser micro displacement measurement,the magnetization and magnetostriction characteristics of amorphous strip are measured by using magnetic characteristics measurement equipment.The magnetization and magnetostriction characteristics of annealed amorphous core were measured with a small-scale amorphous prototype and a Doppler laser vibrometer.The influence of annealing treatment on the magnetic properties of amorphous alloy materials was compared and analyzed.(2)The magnetic field mechanical field coupling three-dimensional numerical model of the amorphous transformer prototype is established.Based on the measured data of magnetic properties,the flux density distribution of the core of the prototype is calculated and analyzed,and the vibration calculation and analysis are realized by considering the magnetostrictive effect.The vibration of the sample core under the rated flux density is compared with the numerical model calculation results to verify the rationality of the numerical calculation and the accuracy of the measurement of the magnetic properties of the amorphous alloy before and after annealing.(3)In order to study the effect of clamping force on the magnetic properties of amorphous alloy rolled iron core,a measuring platform for magnetic properties of amorphous alloy rolled iron core under clamping stress was built.The changes of magnetic properties of the core under different clamping forces were compared and analyzed,and the corresponding magnetostrictive curves of the core under different clamping forces were measured.Vibration analysis equipment was used to measure the vibration of the core under each clamping force,and the influence of the clamping force on the magnetic properties and vibration of the amorphous alloy roll core was studied.(4)The numerical calculation model of the amorphous core prototype is established,and the magnetic characteristic measurement data of the core under the clamping force is substituted.The relationship between the magnetic flux density and stress distribution of the core and the clamping force is analyzed.The vibration acceleration calculation results of the core are compared with the vibration measurement results of the prototype,and the influence of the clamping force on the amorphous alloy roll core is analyzed.The research results of this paper can provide an analysis method for the accurate prediction of the vibration of amorphous alloy transformer products;in addition,it is of great significance for the optimal design of amorphous alloy transformer to improve its operation economy and environmental protection.