Structural Design And Control Research On A Novel Vehicle-mounted Flywheel Energy Storage System

To cope with the problem of energy shortage,China has put forward strategic measures to promote energy transformation in the "14th Five-Year Plan".As the vehicles increased,a large number of retired batteries(mainly to chemical batteries)will be brought.In our country,the chaos of chemical battery recycling is common.A large number of pollutants discharge directly,which brings irreversible harm to the environment.Batter than chemical energy storage,the flywheel energy storage system has the advantages of no pollution,high energy efficiency,high power density and long cycle life,etc.However,there is no comprehensive integration of energy storage,stability,weigh and anti-interference characteristics,which limits vehicle-mounted flywheel energy storage system rapid promotion.This paper mainly focuses on the design of a new vehicle-mounted flywheel energy storage system.The main research work is as follows:Firstly,the research on background of vehicle flywheel battery is introduced.The status and development trend of flywheel energy storage system and magnetic suspension support system are introduced.Finally,the purpose of this research and the main content of this paper are simply described.Secondly,based on the perspective of electric vehicles,the working principle is expounded.Different from the traditional topology with inertia spindle structure through the motor and flywheel causing large size,a new kind topology with embedded in the high level of integration is designed.Then,based on analyzing the existing flywheel energy storage system,the design requirements of the overall topology and key components are determined.Thirdly,a novel vehicle-mounted flywheel energy storage system is proposed,which has the advantages of superior energy storage characteristics,high integration,safety and stability.The key components such as flywheel,magnetic bearing and motor/generator are analyzed in detail and optimized designs are carried out.Firstly,in order to achieve high integration,high energy storage density and high stability,an irregular solid flywheel is designed.The flywheel structure with the best energy storage performance is obtained by multi-objective optimization.The safety and stability of the flywheel are verified by the strength simulation.Secondly,in order to improve the stability of the system under complex running conditions,a combined AC hybrid magnetic bearing with "spherical" element is designed.The working principle of the combined magnetic bearing are introduced and verified,and the optimal design is carried out.In addition,the anti-interference characteristics of the combined magnetic bearing with "spherical" element is verified by the finite element software.An external rotor brushless DC motor with light weight,high efficiency and low loss is designed.Finally,according to the optimization design,the prototype of the vehicular flywheel energy storage system and the experimental platform are built.To verify the feasibility of the vehicle flywheel energy storage prototype and the anti-interference performance of magnetic bearing-flywheel system,the stiffness experiments and performance tests are carried out,and the detailed analyses are conducted.