Short-circuit fault characteristics analysis in new-type power systems under different LVRT control strategies and SCR factors

In the traditional short-circuit fault characterization of transmission lines of new-type power systems, one end is equivalent as the traditional AC system dominated by synchronous generators, while the other end is the new energy field station connected. The short-circuit fault characterization in this scenario can provide support for the research and test verification of new principles of longitudinal differential protection, distance protection and current protection for new energy-connected distribution lines or transmission lines. However, in the context of large-scale new energy plants coming into operation on the transmission grid system side, both sides of the new power system lines in some regions will be dominated by new energy sources, with weak feeder characteristics at both ends. Taking this as the background of the study, we analyze the short-circuit fault characteristics by taking into account the low-voltage ride-through (LVRT) strategy and the system short-circuit ratio (SCR) index of the new energy stations, build the corresponding distribution network model, and give the short-circuit fault characteristics of some typical fault scenarios, which points out the future challenges of the new type of power system line fault analysis, relay protection, and fault localization.