Application Of Hydraulic Anti-kink System In Single-car Low Floor Tram

As an important part of the single-car low floor tram,hydraulic anti-kink system can prevent vehicle bending on the urban small radius curve.In this thesis,the mechanical-hydraulic system is simulated on a Simulink platform by using AMEsim software and Simpack multi-body dynamics software.The systematic research is carried out from the internal structure,kinematics and dynamics of the hydraulic anti-kink system,which has important engineering application value for realizing the localization of the hydraulic anti-kink system and ensuring the safe operation of the tram.The main research work is as follows:(1)Based on the physical structure and working principle of the hydraulic anti-kink system,the structural components of the system are simulated and the system model is established.Then,the verified AMEsim anti-kink system model and Simpack four-group single-car tram model realized the co-simulation of mechanical-hydraulic system through a Simulink platform.(2)The running attitude of the vehicle with or without anti-kink system is calculated.The results show that the hydraulic anti-kink system can improve the centering ability of the independent wheelset and reduce the wheelset angle on the straight line.On different types of curves,the yaw angle difference between the front and rear carbody and the bogie can be obviously consistent,which effectively reduces the maximum yaw angle of the vehicle and the distance between the end of the carbody and the track center line,and prevents the vehicle from bending on the curve.For the C-type circular curve,the smaller the radius is,the more obvious the effect is.For the S-type curve,the shorter the intermediate straight line is,the more obvious the effect is.At the same time,the anti-kink system also improves the adaptability of trams to line changes,on the lines with different friction coefficients,the vehicle can have a smaller yaw angle and maintain a stable yaw state.(3)The stained condition of the vehicle under the action of the anti-kink system is analyzed.On the C-type circular curve and the S-type curve with the length of the intermediate straight line longer than the center distance of the front and rear bogies,the front bogie generates the torque opposite to the track direction,and the rear bogie generates the torque consistent with the track direction.On the S-type curve with the length of the intermediate straight line shorter than the center distance of the front and rear bogies,the front and rear bogies both generate the torque opposite to the track direction,and the action torque of the hydraulic anti-kink system on the S-type curve is much larger than that on the C-type circular curve.(4)The dynamic performance of the vehicle with or without anti-kink system is compared.The results show that the hydraulic anti-kink system mainly affects the lateral index of the vehicle on the straight line,which can effectively improve the lateral stability and ride comfort.On the C-type circular curve and the S-type curve with the length of the intermediate straight line longer than the center distance of the front and rear bogies,the anti-kink system is not conducive to the front car,but conducive to the smooth entry of the rear vehicle into the curve.On the S-type curve with the length of the intermediate straight line shorter than the center distance of the front and rear bogies,the anti-kink system reduces the vehicle dynamic performance and is not conducive to curve passing.It is suggested that the curve perception strategy should be applied on the inclement S-type curve to close the anti-kink system in time.