Research On Dynamical Analysis And Control Of Pantograph-OCS System

The total length of high-speed railway in China has exceeded 29,000 kilometers according to the statistics by National railway administration of China until the end of 2018.The development of high-speed railway is not only reflected in the operating mileage,more evident on the running speed of trains.So it is really important to ensure the safe and stable running of high-speed trains.The Pantograph-OCS system is one of the three keys that restrict the train running speed and affect the train dynamical performance.When the locomotive runs at high speed,the nonlinear dynamic phenomena such as lag and large deformation will occur in the Pantograph-OCS system,which will seriously affect the service life of the Pantograph-OCS system and the locomotive running safety.Therefore,it is of great engineering significance to study the complex dynamics of high speed train Pantograph-OCS system and control it.This paper mainly studies the modeling,dynamic characteristics and vibration control of pantograph of high-speed train.The main contents are as follows:(1)The Pantograph-OCS system,the definition and basic properties of fractional order calculus and fractional order PID control are briefly introduced.In the simulation of air spring in pantograph,fractional order model is used.Finally,a unary fractional-order model of Pantograph-OCS system is established.(2)The dynamical characteristics of the Pantograph-OCS system under the influence of the Duffing oscillator is studied.The fractional-order parametric model of Pantograph-OCS system under the influence of Duffing oscillator is established.The first order approximate analytical solution of the system is obtained by the average method.The general forms of equivalent linear damping and equivalent linear stiffness of the system are defined.The analytical results are verified by power series method.Finally,the effects of Duffing coefficient,fractional-order coefficient and order on the dynamical characteristics of the system are analyzed.(3)The dynamical characteristics of Pantograph-OCS system under fractional-order PID control based on displacement feedback is studied.The first order approximate analytical solution of the system is obtained based on the average method.The analytical results are verified by power series method.This paper mainly analyzes the influence of fractional-order PID control parameters on the dynamical characteristics of Pantograph-OCS system.Finally.The advantage of fractional-order PID control is verified by comparison.(4)The complex dynamical characteristics of Pantograph-OCS system under fractional-order time-delay PID control is studied.The first order approximate analytical solution of the system is obtained by the average method.By comparing the numerical solution with the analytical solution,the accuracy of the results and process is verified.The effects of the fractional-order time-delay PID control parameters and time-delay parameters on the dynamical behavior of the Pantograph-OCS system is analyzed.