Research On Train Vibration Analysis And Control Under Strong Wind Environment

As a kind of random excitation,wind interacts with train wind,which would produce strong wind load to be applied to the surface of train body,and then result in traversing,floating and rolling of train.Considering the increasing speed of trains and the increasing proportion of bridges in the total lines,the impact of windy environment on trains would be more significant,and the response results of bodies would be intensified,which would eventually lead to the reduction of train running stability,and even safety accidents such as train derailment and overturning.Therefore,it is of great significance to analyze the train vibration and control system in windy environment for ensuring the safe and stable operation.In this paper,harmonic synthesis method and Fast Fourier Transform(FFT)are used to simulate the fluctuating wind field,and then solve the wind load.Then,SIMPACK software is used to simulate the vibration response of CRH2 EMU train model under wind load impact.According to a large number of vibration response results,the corresponding relations are summarized,the universe expansion factors under different train speeds and wind speeds are obtained,the design of variable universe fuzzy controller is completed,and the train variable universe fuzzy control full active suspension system is established.Finally,SIMPACK software is also used to simulate the application process of train full active suspension system in windy environment,and the safety and stability of train operation are evaluated by derailment coefficient,wheel weight shedding rate,wheel-rail lateral force,overturning coefficient and Sperling index.The main conclusions of this paper are as follows:(1)According to the simulation results of fluctuating wind field,it can be found that the fluctuating wind speed basically falls within the range of ±5 m/s,and occasionally there would be ±15 m/s wind speed.With the increase of average wind speed,the fluctuating wind speed would also increase accordingly.(2)The wind load is applied to the train,and the 0.06 g body lateral acceleration limit and the 0.1g body vertical acceleration limit are introduced to analyze the body response acceleration.It can be found that the body lateral acceleration has a certain probability of exceeding the limit,and the body vertical acceleration response basically does not exceed the limit.It also shows that the traverse movement of the train body is obvious in windy environment.(3)The application of variable universe fuzzy controller in the train lateral active suspension control system makes the response result of the train in strong wind environment obviously better than that of the passive suspension,especially for the lateral movement and roll of the body,the active suspension system obviously has a better suppression effect.When the speed and wind speed decrease,with the compression of universe,the fuzzy control rules become more detailed,and the variable universe fuzzy controller of train lateral active suspension control system can play a better role in suppressing lateral vibration.(4)By analyzing derailment coefficient,wheel load reduction rate,wheel-rail lateral force,overturning coefficient and stability index,it can be found that wind speed is the main reason that aggravates train vibration and leads to the deterioration of train dynamic performance,whether it is the safety problem or the stability problem of train operation.In addition,besides wind speed,train speed would also affect the safe and stable operation of trains.Compared with the uncontrollable factor of wind speed,the safety of train operation can be improved by reducing the train speed during train operation.