Dynamic Active Control Of Pantograph For High-speed Railway Based On Genetic Algorithm

With the increase of train velocity,the fluctuation of contact force between pantograph and catenary becomes more severe,and the disconnection between pantograph and catenary becomes frequent,which affects the power transmission quality of train.In the case that the optimization of the structure parameters of pantograph and catenary is difficult to improve the train flow,active control of pantograph is an important method to solve and improve the power transmission of high-speed pantograph network.LQR(linear quadratic controller)active control strategy can often achieve good control effect because of its strong robustness and dynamic performance,and it has the advantages of simple structure,easy to operate,which is more suitable for active pantograph control.The main contents include:Firstly,DSA350 S and SS400 pantograph and catenary were taken as the research objects to establish a ternary coupling dynamic model,and the simulation of pantograph-catenary contact force when the train is running in the velocity range of 0-350km/h was carried out.The relationship between the standard deviation of contact force and velocity and the relationship between the mean value of contact force and velocity under passive control were analyzed.The velocity before the current transmission performance deteriorates is selected as the active control intervention velocity.Secondly,the control effect of the traditional artificial LQR control of pantograph in the intervening velocity range was analyzed,and the optimization of the weighted matrix of pantograph LQR by genetic algorithm was carried out.The real coding mode was selected and the appropriate algorithm function was matched to improve the standard genetic algorithm.The solution of the algorithm was analyzed by taking the performance optimization degree of a single fixed velocity as the objective function.Aiming at the problem that the performance of the optimal matrix was affected by the velocity,a multi-speed LQR control was designed to optimize the power transmission performance at multiple speeds,and a piecewise LQR control was designed to switch the weighted matrix according to the velocity.Finally,the test was carried out at [110,350]km/h with fixed velocity and uniform velocity.The two control modes meet the design criteria,effectively suppressed the contact force fluctuation and optimized the flow receiving performance.Among them,the multi-speed LQR is easier to design,and the piecewise LQR control has better optimization degree.DSA350 S,SS400 pantograph and catenary system can reduce the standard deviation of contact force by 21.64% and 32.76% respectively under the uniform velocity environment in the whole interval under the piecewise LQR control,and the drop of contact force under the multi-speed LQR control is 12.89% and 16.09% respectively.