Influence Of Secondary Topology On Lateral Force Of Linear Induction Motor

The continuous development and innovation of the urban rail public transportation system provides a variety of options for people to travel.At present,most of the drive systems of subways in urban rail transit are driven by traditional three-phase induction motors.However,with the continuous advancement of technology,the subway and medium-speed and low-speed magnetic levitation lines driven by linear induction traction motors have gradually entered our lives.Compared with the traditional rotary electric motor-driven subway,the linear induction traction motor drives the vehicle with the characteristics of small turning radius,strong climbing ability and low noise.It is well adapted to the increasingly tight urban underground space and meets people’s ride comfort.In the subway planning,corners and ramps are inevitable.The subway vehicles pulled by linear induction motors will cause different degrees of initial and secondary shifts of the motor through non-straight line segments.This thesis focuses on the electromagnetic characteristics and force characteristics of linear induction traction motors in the case of primary displacement.First of all,the thesis reviews the origin and development of linear motors,and investigates the research status of linear motors at home and abroad in recent years.Imagine the direction of linear induction motors that can be further developed.This thesis has detailed the development and innovation of its secondary structure.Secondly,the composition and classification of linear induction motors are introduced.The principle of linear induction motors and the unique lateral and longitudinal edge effects are highlighted.Linear induction motors have their own unique advantages and disadvantages.By continuously improving their performance,they play an increasingly important role in the field of rail transit.This thesis gives a detailed summary of the causes and structural changes and characteristics of linear motor secondary displacement.Thirdly,the formula is derived from the three-dimensional finite element analysis of linear induction motor,and the role of finite element method in the analytical calculation of linear motor is continuously deepened.The three-dimensional analysis models of flat-plate,cat-type and laminated-type linear induction motors were established by ANSYS,and the changes of motor force characteristics and magnetic field characteristics at the primary displacement were analyzed.At the same time,in the analysis of the laminated linear induction motor,the influence of the number of laminations on its motor characteristics is also analyzed.Finally,by comparing the flat-type,cap-type and laminated linear induction motors,the lateral force,thrust,normal force and magnetic field of the linear induction motor in different secondary topologies are summarized and analyzed.Changes in characteristics,etc.In the process of characteristic comparison,the advantages and disadvantages of various secondary structures are obtained,which provides theoretical support for engineering practice.