Abstract: A single-end line protection based on reflection coefficient and model matching is proposed to address the issues of internal remote high-resistance fault rejection and lightning interference misoperation of line protection in flexible DC power grid.First, based on the reflection coefficient of voltage traveling waves, a directional criterion is constructed to avoid protection misoperation under backward faults or lightning stroke. Secondly, using the voltage traveling wave transfer function to analyze internal short-circuit faults, as well as the function model satisfied by the initial traveling wave of fault voltage at the protection point under forward external faults or forward lightning strikes, a recognition criterion based on model matching is designed according to the different matching degrees between the first traveling wave of fault and the reference function model. Then, a complete single-end line protection scheme is constructed by combining the starting criterion and pole-selection criterion. Finally,the PSCAD simulation results verify that the proposed protection scheme has high reliability and can withstand 500 Ω transition resistance and 20 dB noise.