The Study On Steering Technology Of Light Rail Vehicle With Independent Wheel

Light rail transit has the advantages of large capacity and low cost.100% low floor light rail vehicles mostly adopt independent wheel,which makes the children and the elderly getting on or off convenient to satisfy the humanized construction of the city.However,the independent wheel has some problems such as poor steering force and flange partial wear.Therefore,this paper has completed the following research on the steering technology of LRV with the independent wheel:Firstly,the design of light rail vehicle and bogie is studied.This paper analyses the structure of light rail vehicles at home and abroad.We analyze the curve negotiation problems of several mainstream vehicles by topology,the influence of wheelset type on low floor rate of vehicles and the arrangement of driving devices of bogie with independent wheel.the gear matching formula and transmission law in gear train transmission system: The gears in the transmission gear train can realize differential control of the coupling wheelset under the condition of matching teeth.One kind of coupling independent wheel structure with active planetary differentia is presented.Secondly,the steering control of independent wheel with the differential is studied.Based on the wheel-rail relationship,the creep force of the coupling independent wheel is derived.The coupling independent wheel has longitudinal creep force and rotary torque,which has the ability of automatic alignment.Then,it is analyzed the actively steering control based on the speed difference between left and right wheel and derives the kinematics equation of independent wheel.The speed difference between the left and right wheels is determined by the vehicle speed and the radius of curvature which the wheelsets is located on the line.The wheelset can reach the ideal state that the wheelset lateral shift is zero when it reaches steady state on the circular curve.Finally,the vehicle dynamic models of rigid wheelset bogie,fully independent wheel bogie and longitudinal coupling independent wheel bogie with active control are established in SIMPACK.The simulation results show that: the rigid wheelset and the longitudinal coupling independent wheel have the ability of alignment in straight line.And fully independent wheel only recovers slowly to the rail center by gravity restoring force.The small radius curve passing ability of rigid wheelset and fully independent wheel is poor,because their lateral shift and attack angle are larger.However,when the rigid wheelset is articulated and select the appropriate rotation stiffness,its curve negotiation ability is optimized.Coupled wheel’s small radius curve negotiation ability is best,with actively controlled based on the speed of left and right wheel.