Research On Strategy Of Active Radial For Metro Vehicle Bogie

As an urban rail transit mode with large volume and high speed,metro plays an important role in the daily travel of residents in big cities.In the design process of metro bogie,it is necessary to coordinate the contradiction between running stability and curve negotiation performance.In order to ensure the running stability of vehicles,the longitudinal positioning stiffness of wheelsets is often set to be large to prevent hunting instability.Because there are many small radius curves in the subway line,the wheels are seriously worn when the vehicle passes through the curve,which has become a major problem faced by the subway operation departments.As an effective method to solve the above problems in theory,the active radial technology of bogie wheelset has a very important application prospect,and has become a research hotspot of urban rail transit vehicles.Rocker type journal box positioning device has been widely used in metro bogie,which has the advantages of few components,easy maintenance and easy to meet the best design requirements of bogie suspension system.In this thesis,a domestic A-type metro vehicle with rocker type journal box positioning device is taken as the research object.Firstly,the structures of several existing wheelset active radial devices are analyzed,and then a new type active radial device for rocker type journal box positioning bogie is designed according to the principle of wheelset active radial.The active radial device integrates two plunger cylinders into the rubber joint,and the plunger can push the journal box to move relative to the bogie frame.When the vehicle passes through the curve,the longitudinal position of the journal box relative to the frame becomes controllable by controlling the telescopic displacement of the plunger,so as to realize the active radial steering of the wheelset.Using AMESim and MATLAB/Simulink software,the model of controllable rubber joint device and control system are established respectively,and the performance of the device is analyzed.The finite element model of the key component of the device is established by using Hyper Mesh software,and its static strength is checked by using ANSYS software.Finally,by establishing the simulation model of metro vehicle equipped with active radial bogie,the dynamic performance of vehicle on small radius curve line and straight line line is analyzed respectively.The research results show that,compared with the traditional bogie,the active radial bogie makes the angle of attack between the wheelset and the rail tend to zero when the vehicle passes through the small radius curve,and the total transverse force of a single bogie acting on the rail outside the curve decreases by 74.87%.Besides,the state of the front wheelset of the bogie is changed from “high wear” to “low wear”.The proposed controllable rubber joint device can effectively improve the curve negotiation performance of metro vehicles,and at the same time,it will not cause the deterioration of vehicle running stability and ride comfort.The designed active radial device based on controllable rubber joint and its research provide a technical idea for the engineering application of wheelset active radial technology.