Performance Analysis Of Vehicle-mounted Linear Generator In High Speed Maglev Train With Multiple Operating Attitude

With the rapid development of the world economy,the rapid growth of urban population density,the increase in people's travel volume and the expansion of the scope of activities,higher demands have been placed on the high-speed and greening of public transportation systems.The traditional wheel-rail system is out of reach,and the superconducting magnetic levitation train meets the increasing demands of rail transportation due to its advantages of high speed,strong climbing ability,environmental friendliness,and no noise.The maglev train fundamentally overcomes the problems of the traditional train wheel-rail adhesion,mechanical noise and wear,etc.,and achieves high-speed operation without mechanical contact between the train and the ground track.The speed of superconducting magnetic levitation trains reaches 500 km / h and above,and the traditional mechanical contact power supply method is no longer applicable.It is prone to problems such as short life,large loss,heat generation,poor stability,and large wind resistance.Therefore,the use of on-board linear generators to supply power to the electrical equipment of superconducting maglev trains has become a necessary technology and key research direction for the development of maglev trains.First,the thesis reviews the origin and development of maglev trains,expounds the research status of maglev trains at home and abroad in recent years,and makes a detailed evaluation of the performance of various power supply systems of superconducting maglev trains,indicating the necessity of vehicle-mounted linear generator.Compared with other power supply systems of magnetic levitation train,on-vehicle linear generators have the advantages of simplicity,convenience,high durability,environmental friendliness,and high reliability.Therefore,it is important to study the performance of on-vehicle linear generators for superconducting maglev train power supply systems.Next,the topology of the vehicle-mounted linear generator is introduced,the complete power supply system of the linear generator and its advantages and disadvantages are explained.The distribution of the magnetic field of the coils laid on both sides of the track was analyzed,and the principle of linear generator using harmonics to generate electricity was given.Secondly,the characteristics of on-vehicle linear generators were studied by the method of three-dimensional finite element analysis.Focusing on the analysis of the changing law of the magnetic field and eddy current of the linear generator under different running attitudes,different speeds and different suspension heights,the power of the linear generator and its influence on the propulsion and suspension system of the train were calculated and analyzed.Finally,the influence of the eddy current generated by the superconducting coil Dewar shell on the performance of the linear generator is studied,and the structure of the Dewar shell was optimized.According to the analysis of the performance of the linear generator under the multi-operation attitude of the maglev vehicle,it provides theoretical basis and data support for engineering practice.