This paper studies the method of the digital signal processing about the base wave phase synchronizationS based on Electronic Transformer. Because the widely applied phase synchronization method based on the Lagrangian interpolation theorem has a problem of heavy computation, Fristly we studied a two-point interpolation algorithm is studied in this paper. SBecause of the disadvantages, we design a precision correction methods based on analog filter. By the analog filter though the transformation. We obtain the transfer function in the discrete domain. SBy the simulation, Algorithm has the ideal curve of amplitude and phase. Finally because of the the difference between Transformer and the Smismatches of the digital integration, which Lead to a bad transient characteristic of the electronic transformer, we Simproved the integral algorithm, through the simulation, the algorithm can restore the original waveform Sperfectly.