Research On Charge-discharge Characteristics Of Flywheel Energy Storage System Based On Superconducting Magnetic Bearing

High-temperature superconducting flywheel energy storage system(HTSFESS)is a special structure of flywheel energy storage system.In this paper,the charging and discharging characteristics of the HTSFESS are studied from the aspects of its principle,structure and electrical control.In principle,the rotational speed of HTSFESS can reach several hundred thousand revolutions,and the power and energy density of HTSFESS are high.However,due to the special structure and operation mechanism of the HTSFESS,the primary and secondary eccentric operation of the flywheel rotor will occur in the process of operation,which will affect the charging and discharging characteristics of the HTSFESS,and it will cause the flywheel out of control operation in serious cases,.Therefore,the study of the operation of the HTSFESS in the eccentric state cannot only make us understand the operation characteristics of the flywheel in extreme cases,but also monitor whether the eccentric operation of the flywheel occurs through the electrical indicators,which is of great significance to the actual operation of the superconducting flywheel energy storage device.In this paper,the charge and discharge simulation model of flywheel energy storage device is built by using SVPWM control method in Matlab / Simulink software.Then,based on the actual HTSFESS,the charge and discharge characteristics at different speeds are tested and compared with the simulation results.Based on the flywheel rotor dynamics model,the characteristics of the primary and secondary eccentricity of the permanent magnet synchronous motor rotor in the HTSFESS are studied.The whole charging and discharging system is built by the joint simulation of the three software ANSYS Simplorer,ANSYS Maxwell and MATLAB / Simulink,and the influence of different eccentricity types on the charging and discharging characteristics of the flywheel system is completed.