The Preliminary Research Of Very-high Speed Bogie Parameter Matching

In order to better realize China’s high-speed rail economic use, we must correct cognition the restricting factors of high-speed wheel/rail speed limit in theory. Through the very-high speed bogie prospective study to improve the technical way of high speed wheel/rail technology security redundancy and discuss high-speed wheel/rail speed limit and the main restricting factors. Although there are three creep theories which have different cognitive in wheel spin creep, so wheel/rail speed limit is still a hot issue, but according to the theory of Wicken, wheel spin creep has become one of the main factors of restricting the wheel/rail speed limit, then,we must earnestly implement high-speed Rail(HSR) economic use.By the guidance of the anti-hunting frequency spectrum characteristics of the matching principle and Germany’s ICE3bogie as a benchmark bogie.In this paper, basing on the linear stability analysis method to guide the nonlinear dynamic analysis, to formulate the very-high speed wheels matching and bogie parameter optimal distribution scheme. For very-high speed wheels matching, the minimum equivalent conicity is moderately improved to0.22. In order to absorb higher frequency instability of the hunting energy, appropriately raise the anti-hunting series stiffness. According to the motor stability property analysis, two very-high speed bogie parameters configuration schemes have finished. In order to keep the relationship of wheel/rail lateral dynamic balance, the optimal distribution scheme is determined, the maximum equivalent conicity under0.52, the lowest nonlinear critical speed close to or more than600km/h. Dynamic simulation analysis shows that when more than400km/h high-speed use, there have the following three major technical problems, so very-high speed bogie lost commercial use value:①Sachs anti-hunting damper performance reliability. By comparison with actual rolling radius and the abrasion index, wheel/rail has more obvious rim roots or rim edge grinding under the very-high speed running in new state. By the anti-hunting damper hard constraints, the transverse impact will cause the anti-hunting damper oil leakage fault, so its performance is difficult to guarantee.②The body lateral acceleration response frequency band broadening. The stronger the anti-hunting high frequency impedance, car body shaking head big damping is more outstanding. The lateral disturbance enhancement that vehicle body to a bogie interface may lead to lower car equipment of rubber suspension transverse coupling vibration. There is no doubt that this has a negative impact to technology of vehicle service life30years constitute.③The self-excited vibration of motor lateral swings tend to instability. Due to the high-damping of carbody yaw, the front carbody of high frequency impedance is bigger than rear carbody, so the front bogie motor suspension yawing showed a trend of "pendulum". With the speed increase, the equivalent conicity become increase, at last the front motor suspension’s "back pendulum" is more and more strong.China’s high-speed trains impact600km/h, which has realistic engineering significance and technical feasibility. Unlike previous wheel/rail speed limit exploration, very-high speed bogie optimal distribution to ensure its stable performance and high speed wheel/rail speed limit research will explore the restriction of wheel-rail creep effect. Dynamic simulation show that when the speed is close to600km/h, the wheels spin creep close to or more than0.6, which will produce longitudinal creep instability problems, such as stick slip vibration phenomenon. Of course, it can take the necessary technical measures to slow the longitudinal creep instability, such as rail sprinkler and forming oxide layer, etc. But sheen’s theory shows:spin creep has "saturated" characteristics to lateral creep force, so speed limit is inexistence. If high speed wheel/rail technology exists speed limit, the bogie parameter must be unified optimal match, and300km/h high-speed applied more emphasis on the robustness of the disturbance of natural factors.