Active Steering Control of Railway Vehicles with Securing Stability and Its Running Safety

在低速曲线通过条件下，比较了三轴转向架车辆与两轴转向架车辆在低速曲线通过条件下的运行安全性。结果表明，急曲线上的脱轨裕度显著降低，强制转向机构对提高行车安全性是有效的；其次，本文提出的主动转向机构能有效地减小曲线区段外轨接头处轮轨间的侧向力，并在转向反转等控制失灵导致攻角增大的情况下，对行车安全性进行了检验。结果表明，半径小于等于350m的曲线段脱轨系数比落在建议设置防脱轨的范围内；对于独立旋转车轮的货车，可以利用非旋转车轴上两个驱动轮之间的牵引力扭矩差进行转向。所提出的控制律有可能在较宽的曲线半径范围内，特别是在陡峭的曲线上，减小IRW的侧向力。在转向控制中，货车前后桥转向方向一致，建立了轮缘爬坡脱轨的分析模型。在小型单轴载货汽车上的试验中，确定了攻角增大或车轮载荷减小时车轮的轮缘爬升。这些趋势在数值模拟中也得到了类似的模拟。然而，在轮重动态降低的情况下，轮缘爬升的高度与实验结果不同。仿真结果表明，车轮动态减载对爬升高度影响不大。

The running safety of three-axle bogie vehicles that seemed to have more possibility of derailment was compared with two-axle ones under the condition of low-speed curve negotiation. As the result, it was shown that the margin up to derailment decreased remarkably on sharp curves and forced steering mechanism was effective for the improvement of the running safety.Then, it was shown that the active steering mechanism proposed in this study was effective to reduce the lateral force between the wheel and rail occurred at outer rail joints in curved section.And, the running safety was examined on the case in which angle of attack increased due to the malfunction of control such as the reverse steering. As the result, it was estimated that the derailment coefficient ratio of curve sections of radius less equal 350 m fell in the range in which the installation of derailment prevention rail was recommended.In case of the trucks with independently rotating wheels, steering can be done using traction torque difference between two driving wheels on a non-rotational axle. The proposed control law has a potential to reduce the lateral force of IRW over the wide range of curve radius, especially in sharp curves. In the steering control, the front and rear axles in a truck are steered in the same direction.Next, an analytical model for simulating the flange climb derailment was developed. In the experiment with scaled single-axle truck, flange climbing of wheel were confirmed when the angle of attack increased or the wheel load decreased. These tendencies were similarly simulated in the numerical simulation. However, the height of flange climbing under the dynamic reduction of wheel load differed between the experiment and the simulation. The effect of dynamic reduction of wheel load on the climbing height was small in the simulation.