Research On Fast Simulation Method Of Electromagnetic Radiation Of Arc Between Pantograph And Catenary

In the high-speed railway system,the pantograph-catenary arc is one of the most important sources of electromagnetic disturbance.Arc disturbance energy spectrum is very wide,it will not only cause the impact of overvoltage on the on-board equipment,but also the high frequency electromagnetic pulse generated by the arc will cause electromagnetic interference to the on-board sensitive electronic equipment and the railway surrounding environment through a variety of coupling ways.So the electromagnetic harassment of pantograph-catenary arc is an important research content in the field of railway electromagnetic compatibility.In this thesis,the rapid simulation problem of multi-scale spatial pantograph-catenary arc radiation field of the Key Laboratory of Electromagnetic Environmental Effect and Information Processing in Hebei Province is discussed.The main work of this thesis is summarized as follows:(1)Research on parallel computing Technology of train space radiation fieldIn order to solve the problem of low efficiency of serial FDTD method in processing large-size targets,this chapter studies parallel FDTD method in detail.Firstly,the principle of parallel FDTD method and the overall implementation process are described,and the fast grid partitioning of complex models is realized.The threedimensional parallel FDTD method is used to realize the rapid calculation of the train space radiation field,and the accuracy of the realized parallel FDTD method is verified.The parallel efficiency can reach more than 70% through analysis,which provides a parallel basis for the subsequent realization of the train Pantograph-catenary arc coupling calculation.(2)Research on modeling method of electromagnetic radiation effect of pantograph-catenary arcBecause there are fine targets such as overhead contact line and ground system,FDTD method requires a large amount of mesh.In this chapter,the transmission line equation and FDTD method are combined to achieve the rapid calculation of contact line electromagnetic radiation.The equivalent circuit model of the grounding system is established,which avoids the direct modeling of fine structure and reduces the amount of grid calculation.By integrating the above numerical calculation methods,an efficient hybrid FDTD parallel algorithm is formed,the calculation speed is increased by 46%,and the rapid simulation of the electromagnetic radiation of the pantographcatenary arc of the train arc is realized.(3)Research on the equivalent modeling and rapid prediction method of pantograph-catenary arc electromagnetic radiationLimited by the need for a large amount of grid when the full wave algorithm simulates the distribution of train radiation field,the computational efficiency is low.In this chapter,the traditional electromagnetic simulation and machine learning method are combined to study the equivalent modeling method of Pantograph-catenary arc electromagnetic radiation in the Pantograph-catenary arc grid,so as to realize the rapid prediction of arc radiation field.By extracting the current distribution along the arc through the contact line,the corresponding equivalent dipole array was established,and the extreme learning machine was used to establish the rapid prediction model of arc radiation field in the arc grid.Finally,the reliability of the prediction model was verified.