| The Switched Reluctance Generator(SRG)is widely used in wind power generation due to its simple structure,high efficiency and low manufacturing cost.However,the biconvex structure and the highly non-linear nature of the SRG make the vibration and noise of the SRG much more severe than that of a permanent magnet motor,limiting its operation and application in demanding environments.This paper therefore aims to optimise the structure of the generator and suppress the vibration noise,and conducts corresponding theoretical analysis and experimental verification.This paper is based on a new type of Deflected Dual-stator Switched Reluctance Generators(DDSRG),which is designed and studied in terms of solving the electromagnetic characteristics of the generator,studying the vibration response of the generator and optimising the structure of the generator for vibration reduction.This study provides some theoretical references and optimisation ideas for practical engineering.Firstly,the analysis of the electromagnetic field characteristics of the SRG and the suppression of electromagnetic vibration are summarised in a large amount of domestic and international literature,and various methods of suppressing electromagnetic vibration are studied,with emphasis on two methods of suppressing motor vibration and noise.For the model of the DDSRG the structural characteristics of the double stator and the power generation principle of deflection operation are elaborated,the basic torque,voltage,linear mathematical model and non-linear mathematical model of generator operation are derived and calculated,and the power generation current and inductance characteristics of the double stator generator are obtained.The non-linear magnetic chain and current characteristics of the generator at different speeds are simulated using the finite element software Maxwell,and the feasibility of the generator operation is verified by conducting power generation experimental comparisons with the DDSRG power generation experimental platform built.By combining electromagnetic field theory,analytical calculations and harmonic decomposition are carried out around the magnetic flux density and the electromagnetic radial force(ERF)of the DDSRG.A three-dimensional physical model of the generator is also established,and the analysis of the radial and tangential magnetic density of the generator is completed by the finite element method,and the specific magnetic field law in both time and space dimensions.Combining the theoretical analysis of the ERF with the amplitude and waveform of the radial and tangential electromagnetic forces,the comparison identifies the radial forces as the main cause of vibration noise.At the same time,the electromagnetic characteristics and ERF waveforms of the generator under static eccentricity are analysed and simulations are carried out to obtain the radial force variation patterns under different eccentricity angles and eccentricity directions.Then,the vibration mechanism is studied and discussed,the process and principles of electromagnetic-vibration multi-physical field simulation are introduced,and the modal analysis of the inner and outer stator is carried out for the model of the DDSRG.Also taking into account the practical situation,housing constraints are added to the stator and the inherent vibration frequencies and vibration diagrams of the inner and outer stator are solved.By using the electromagnetic force as an excitation for harmonic response analysis,the frequency response results of the vibration of the generator operation are obtained,the law of stator resonance is compared and analysed,and the experimental platform built for experimental verification.Finally,a method of suppressing vibration by means of slotting on both sides of the stator is proposed,and the feasibility of slotting is demonstrated by means of the magnetic circuit decomposition method.The effects of different parameters of slotting height,slotting depth and slotting width on the average torque and ERF are analysed.The slotting parameters with the optimum ERF amplitude are obtained without any reduction in the average torque,which not only reduces the manufacturing cost but also greatly reduces the radial force amplitude by 22.6% and has a more obvious vibration damping effect,providing a reference for future motor vibration suppression. |
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