Temporal Impact of High-Speed Railway Traction Load on Grid Voltage Considering the Uncertainty

With the increasing of high-speed railway traction load, the characteristics of single-phase, high-power, and spatiotemporal movable have brought major impacts and challenges to the voltage quality of grids. In this article, a probabilistic analysis framework with uncertainty is investigated to implement the temporal impact of traction load on grid voltage for high-speed railway applications. First, a single-phase traction power supply system (TPSS) is used, equivalent to a three-phase model based on the port transformation of the traction transformer. Meanwhile, a diffusion-based kernel density estimator (DKDE) is built as the timing probabilistic model of distributed traction loads. On this basis, a timing three-phase probabilistic load flow (3PLF) calculation model is constructed for the power grid connected with traction loads. Specifically, the three-point estimation method (3PEM) based on the correlation is applied to determine the calculation of 3PLF. Finally, the advantages of the DKDE and the 3PEM for the 3PLF are compared and verified. Essential factors such as the number of traction stations and their access method, as well as different levels of correlation coefficient, are contemplated in case studies. The results validated the probabilistic impact of the spatiotemporal movable traction loads on the power grid voltage.