Design Of Tubular Permanent Magnet Linear Generator Of Composite Transformer

With the increasing popularity of automobiles,in order to meet people’s requirements for the comfort,safety and stability of pure electric vehicles,and to overcome the problems of low efficiency and short cruising range of pure electric vehicles,this thesis proposes a tubular permanent magnet linear generator(PMLG)with integrated high-frequency transformer for automobile suspension,so that the device has both transformer and generator functions.According to the vibration characteristics and technical standard of automobile suspension,a tubular permanent magnet linear generator is designed.Because the DC voltage output by the generator after rectification is low,the output voltage level needs to be increased,and then power electronic devices and high-frequency transformer devices must be added.Aiming at the problem of limited space of the automobile suspension system,a structure in which the highfrequency transformer and the generator share the same iron core is proposed.The research work in this thesis is as follows:First of all,consult the relevant literatures on energy capture,simulation analysis and experimental research of automobile shock absorbers,as well as domestic and foreign related research literatures on permanent magnet linear generator type regenerative shock absorbers for automotive suspension,and related research literature on regenerative shock absorbers and energy feed control.Secondly,according to the reciprocating vibration characteristics of automobile suspension,a tubular permanent magnet linear generator for automobile suspension is designed.The basic structure and working principle are introduced first,and then the main dimension relational formula of the rotating electric machine is deduced to obtain the design formula of the tubular linear generator,and the main dimensions of the electric machine are calculated according to the main technical parameters.The three types of magnetizing structures are compared,and the magnetizing structure selected for the permanent magnet is determined on the basis of comprehensive consideration of the performance,manufacturing process and cost factors of the machine.Then,the generating principle of the detent force of the generator is analyzed,and the expressions of the cogging force and the end force are derived respectively.Contrast and analysis of the effects of different slot-pole coordination on cogging force and the end force of the generator at different primary lengths.Then the finite element method is used to analyze the effects of different stator tooth widths and polar arc coefficients on the detent force of the tubular permanent magnet linear generator,and then to optimize the detent force of the generator.Research the output voltage of the generator at different winding phases,model and simulate the optimized generator through the Ansoft simulation software.Finally,the basic structure and working principle of the tubular permanent magnet linear generator of the composite transformer are introduced in detail.By placing the transformer coil and the generator winding coil vertically to reduce the electromagnetic coupling,the highfrequency transformer winding part of the solid-state transformer is designed.Finally,the highfrequency transformer and the generator share the same iron core.After opening the transformer slot on the primary stator core,the effect of whether the transformer winding is energized on the generator output voltage is analyzed.And the external circuit of the tubular permanent magnet linear generator of the composite transformer is added.Simpliler and Maxwell are used for joint simulation analysis to verify the tubular permanent magnet of the designed composite transformer the effectiveness of linear generators.