| The motor is the driving source of the ship’s electric auxiliary engine,and the noise of the electric auxiliary machine is the main source.The noise of the structure is the main effect on the sound radiation during the low speed navigation of the submarine and so on,so it should be strictly controlled.The vibration of the motor is produced by 2 aspects of the excitation source and the structure.The excitation source includes the mechanical excitation force and the electromagnetic excitation force.The mechanical excitation includes the excitation force caused by the machining,manufacturing and assembling of the mechanical parts,such as the rotor unbalance force and the bearing.The electromagnetic excitation force is mainly caused by magnetic density in electromagnetic field,including the electromagnetic excitation force of air gap fundamental wave and alveolar harmonics.In order to reduce the vibration caused by electric motor electromagnetic excitation,this paper studies the electromagnetic excitation mechanism of 2 types of main small drive motor of asynchronous motor and permanent magnet motor respectively.2 kinds of motor theoretical calculation and analysis are carried out by analytic method and finite element method.The laws and characteristics of electromagnetic excitation are found out.The influence of electromagnetic excitation characteristic parameters is studied to find out the influence of electromagnetic field.The main parameters and the influence rules of excitation are identified,and the electromagnetic excitation mechanism of small drive motor is basically found out.On the basis of theoretical analysis,an electromagnetic excitation test bench is built,and motor excitation test is carried out to verify the theoretical analysis.On the basis of finding out the characteristics of electromagnetic excitation and combining with the characteristics of motor structure,the structure and response characteristics of electromagnetic mechanical multi physical field are studied.On the basis of the theory of modal analysis,the modeling method of motor structure is explored by means ofmixed modeling technology,and a physical model to meet the requirements of the process is established,and the simulation and test methods of small drive motor are obtained.On the basis of finding out the characteristics of electromagnetic excitation and motor structure,the simulation calculation and analysis of electromagnetic excitation response are carried out,and the test verification is carried out.The difference between simulation and test results is analyzed.The method and law of electromagnetic excitation and response calculation are found out.The basic method of electromagnetic excitation acoustics design is determined,and some quantitative analysis of the frequency band is carried out to realize the purpose of partial quantitative acoustic design.Finally,based on the characteristics of electromagnetic excitation and the conclusion of structural design,a preliminary low noise motor design method is summarized.Using this low noise design method,a prototype is designed in combination with the needs of engineering practice and low noise technology research.The results of the prototype show that the motor vibration is greatly reduced than the original design method,and the theoretical analysis of the electromagnetic excitation characteristics of this paper is verified.The conclusion is reliable,and the accuracy of the method of motor structure modeling and vibration response analysis is verified.In the first chapter,the design of motor acoustics is summarized and summarized,and the progress and development process of motor acoustics design at home and abroad are analyzed.At the same time,the aim and significance of this research are put forward.In the second chapter,the characteristics of electromotor excitation source are analyzed and analyzed.The main source of motor excitation is classified and summarized.Starting with two kinds of induction motor and permanent magnet motor,the theoretical research of electromagnetic excitation characteristics is carried out.2 methods are used to verify the theoretical research conclusion,and the electromagnetic analytical method is formed,and the physical model of electromagnetic excitation is determined.Acoustics design provides the basis.In the third chapter,electromagnetic simulation calculation and test research and research,the simulation and calculation of electromagnetic field are carried out by numerical analysis method.The mathematical model of electromagnetic excitation and the method of finite element solution are studied,which lays a foundation for the analysis of the influence factors of electromagnetic excitation by numerical method.In the fourth chapter,the influence factors of electromagnetic excitation are studied.On the basis of theoretical analysis and analysis,the simulation calculation of the influence factors of the electromagnetic excitation characteristics of asynchronous motor and permanent magnet motor is carried out by using the finite element method,and the relationship between the influence factors and the electromagnetic excitation is found out,which makes up for the analysis of the analysis.The fifth chapter of the induction motor electromagnetic excitation test verification and research and the sixth chapter permanent magnetic motor electromagnetic excitation test verification and research,respectively carried out the induction motor and permanent magnet electromagnetic excitation characteristics test verification work,designed a special test bench,and according to the simulation calculation conclusion,carried out a number of comparative tests,from the test method,test process,test bench,data analysis.The method and other aspects are verified and analyzed,and the theoretical analysis results of electromagnetic excitation model,analytical calculation and finite element method in the first three chapters are verified,and the shortcomings of the previous theoretical results are found out.The seventh chapter analyses the response analysis of motor structure.On the basis of clear electromagnetic excitation characteristics and clear calculation method,the structure characteristic analysis is carried out.The typical motor is selected and the two dimensional electromagnetic excitation model is used to simulate and study the structure characteristics.The simulation model design law of the structural characteristics of the motor equipment is found out,and the electromagnetic field-the single term of the mechanical field is carried out,and the single term of the mechanical field is carried out.Hybrid analysis and quantitativeacoustic design were initially explored,and the quantitative acoustic design predict ion method of motor was initially explored.In the eighth chapter,the design of permanent magnet motor verification prototype and test verification,on the basis of the first seven chapters,summarize the low noise motor design technology,design a low noise permanent magnet motor from the low noise electromagnetic design,low noise structure design,low noise technology design and so on,and carry out the test verification.The test results show that the motor vibration has been greatly reduced and reached the preview.The ninth chapter makes a summary of the full text,analyses the achievements and shortcomings,and summarizes the design and analysis methods of the equipment,which provides the basis for the comprehensive equipment quantitative acoustic design.At the same time,the quantitative acoustic design of motor is outlined and prospected,providing a basis for quantitative acoustic design of complex generating units. |
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