Research On Transient Calculation Method For Integrated Grounding System Of High-Speed Railway Based On Waveform Relaxation Method

The integrated grounding system is an important part of the high-speed railway system, which plays a vital role in ensuring the safe operation of the railway. With the continuous development of high-speed railway, the reliability of its operation is more and more high. According to the relevant data, lightning accident is one of the important factors affecting the safety of high-speed railway, and simulation calculation of lightning overvoltage for it has a very important significance for the high-speed railway insulation design. This paper is aimed at the problems of modeling of integrated grounding system for high-speed railway and method of time domain calculation under the effect of lightning, combined with National Natural Science Foundation Project "Fast Time Domain Electromagnetic Transient Simulation Technology of the Large Scale Multi-conductors System"(51407073), and the time domain calculation method for the integrated grounding system of high-speed railway and 10 kV through line cable are studied.The high-speed railway integrated grounding system has many characteristics such as the number of conductors, the complex structure, and it is difficulty to direct calculation. Aiming at this problem, this paper implements a time domain algorithm based on the waveform relaxation method, which is combined with the GPU parallel computing. The concrete implementation process of the algorithm is: firstly, the circuit model of the high-speed railway integrated grounding system is established by using Partial Element Equivalent Circuit method(PEEC), a partition strategy based on sensitivity analysis is presented, the whole system area is decomposed by the effective discrimination of the coupling relationship between the conductors, on this basis, the Waveform Relaxation algorithm for the calculation of Lightning Overvoltage in high-speed railway integrated grounding system with large scale is realized; then based on the GPU parallel computing workstation, the simulation calculation of the potential rise of the high-speed railway integrated grounding system is realized by CUDA program; in the end, the Lightning Overvoltage calculation and analysis for single body of the viaduct bridge and 10 kV cable, and the related proposal for lightning protection design is put forward.In this paper, the time domain transient calculation method for large scale multi-conductor system based on the Waveform Relaxation and parallel computing method, On the other hand, it can solve the problem of calculating large-scale system directly, and on the other hand, it can greatly improve the computational efficiency, has a very good application prospect in the area of electromagnetic transient simulation calculation.