Abstract: The key structure of main circuit of a line-frequency synchronous induction motor drive system and its snubber parameters were described. The harmonic wave assimilation algorithm and current control strategy for this system based on flux orientation vector computation were analyzed. The system's current response performance under the typical industrial application condition was studied. It is concluded that the line-frequency synchronous induction motor drive system has excellent current response performance and some similar characteristics compared with the standard synchronous motor.