Structural Design And Analysis Of Composite Material Energy Storage Flywheel Rotor

As a new type of energy storage,flywheel energy storage system has many advantages such as no pollution,long life,wide applicability,energy storage density,charge and discharge speed etc compared to other energy storage methods.Especially with the development of vacuum technology,composite technology and magnetic levitation technology,which has brought a broader research space and application prospects to flywheel energy storage technology.In this paper,the following research is carried out on the composite flywheel rotor: the flywheel rotor stress analysis derivation,flywheel rotor structure optimization design,flywheel rotor stress finite element analysis,and flywheel rotor modal analysis.First of all,the flywheel rotor stress analysis has been derived.Then the theoretical model of the ax symmetric problem of the orthotropic material was established,thus the radial stress,the circumferential stress and the radial displacement of the single ring composite rim under certain rotational speed was deduced,then the three dimensional surface diagram of the stress and displacement of the single-ring rim with the radial position and the rotational speed is plotted by MATLAB software.The stress distribution of the single-ring rim was deduced and the shear stress was related to the angular acceleration.The above analytic derivation can help us to understand the relationship between the parameters better and provide theoretical support for the structural optimization design of the later flywheel rotor.Secondly,the structure optimization design and supporting scheme selection of the flywheel rotor was carried out.Composite method of structural optimization has been adopted to solve the optimization of composite material rim,this project taking the energy density function as the objective function,taking the Tsai-Wu strength criterion as the constraint condition,then the optimal solution of the radius value inside and outside the rim was obtained by using MATLAB software to optimize the composite material rim.Using the optimization design module in ANSYS Workbench,some of the dimensions on the hub are optimized to improve the wheel force.According to the flywheel energy storage system technical indicators,structural design and program selection of other modules of the flywheel energy storage system has been designed.Then,the finite element analysis of the flywheel rotor has been carried out.The influence of the number of ring rings,the radial thickness of each ring,the interference between the ring and the ring,and the influence of the priestess on the rotor stress of the flywheel was studied by ANSYS Workbench software,then this paper meet the strength and energy storage requirements of the composite flywheel rotor model according to above rules.The analyze of stress condition of the flywheel rotor in the static state,the rated speed state and the charge and discharge state was obtained by using ANSYS Workbench,which respectively to judge whether the composite flywheel rotor designed in this paper failed.Finally,modal analysis has been adopted for the flywheel energy storage system.The natural frequency and vibration mode of the system has been obtained by using ANSYS Workbench software,which can predict the vibration characteristics of the system and verify the flywheel system in the normal speed range of security effectively.The influence of radial bearing support span,electromagnetic bearing stiffness and multi-loop assembly interference on the natural frequency of flywheel rotor was analyzed by ANSYS Workbench software,thus the influence law of each factor on the natural frequency was obtained,which can provide support for improving the vibration characteristics of the system.