Abstract: To address the issues of fault current limitation, frequency deviation, and phase angle uncertainty caused by low-voltage ride-through control in wind-storage integrated systems, this paper proposes a longitudinal protection method based on time-matched current waveform comparison. Convert the three-phase currents at both ends of the line into a single-mode current sequence, calculate the longest common subsequence by matching ordered sampling points using Euclidean distance tolerance, and finally determine internal and external faults based on normalized matching similarity. PSCAD/EMTDC simulations show that the proposed method operates correctly under various conditions, including varying transition resistance, 20 dB noise, 15% sample loss, and changes in wind-storage capacity, demonstrating excellent performance.