Research On Vibration And Noise Characteristics Of Single-Winding Bearingless Switched Reluctance Motor For Flywheel Batteries

In recent years,the emergency of traditional fossil energy has caused people to turn more attention to the development of new energy,and energy storage technology has become a worldwide research topic.Flywheel batteries are gradually being valued by scholars at home and abroad because of their high efficiency,high energy density,short charge and discharge time,and environmentally friendly performance.With the advantages of simple structure and high control flexibility,Single-Winding Bearingless Switched Reluctance Motors(SWBSRM)has wide application value in flywheel battery field.However,as the core component of the flywheel battery,the performance of the SWBSRM directly influences the productivity of flywheel battery,the working environment of the flywheel battery running at high speed also has higher requirements for the vibration and noise level of the motor.Therefore,the calculation of the vibration and noise of the flywheel battery SWBSRM is very important for ensuring the stability of the flywheel system and prolonging its service life.Based on the analysis of the structure and operation mechanism of 12/8 pole SWBSRM,a mathematical model is established and its vibration and noise characteristics are deeply studied.The main studies are as follows:(1)The mathematical model of the motor is deduced,and the design equation of the basic size parameters is established according to the structural characteristics of SWBSRM,and the initial structural parameters of the motor are determined from this,which lays the foundation for further study on vibration and noise of the motor.(2)Build a 2-D motor model according to the given design parameters,analyze the suspension and torque performance of SWBSRM to ensure that the initial structural parameters of the motor meet the design requirements.Starting from the air gap magnetic field,the radial electromagnetic force of the motor is analyzed,and the radial and tangential components of the air gap magnetic density are obtained by using a field calculator.Then based on the Maxwell stress equation,the distribution of the radial electromagnetic force of the motor is calculated,and the Fourier Transform is performed to explore the amplitude,order and frequency distribution of the radial electromagnetic force wave.Finally,the effect of different structure components on motor mode is compared by using finite element software.(3)Build a 3-D model for SWBSRM analysis and prediction of vibration and noise,and the radial electromagnetic force is coupled to the inner surface of the stator tooth pole of the motor by magnetic-solid weak coupling method.The vibration response characteristics of the motor under electromagnetic excitation are calculated.Then the vibration velocity is loaded into the inner hole surface of the noise analysis model as the excitation source of acoustic analysis,calculate the motor sound pressure nephogram and the noise distribution curve at different frequencies.The results shows that the SWBSRM vibration noise level corresponds to the frequency component of the radial electromagnetic force wave.When the harmonic frequency is similar or consistent with the natural frequency of the motor,the resonance phenomenon will occur in the motor.(4)Study and analyze the variation of radial electromagnetic force and modal frequency under different values of motor structural parameters,select key structural parameters as optimization variables,and use genetic particle swarm optimization(GAPSO)to optimize the design of motor parameters and determine the final size parameters.By comparing and analyzing the electromagnetic performance and vibration noise level of SWBSRM before and after optimization,it can be seen that the torque and suspension performance have been improved after the optimization,and the vibration acceleration and noise level of the motor have been reduced,verifying the effectiveness of the GAPSO.