Abstract: The dissertation presents a new vector control method based on fixed voltage mode, which is designed by aiming at the defects in traditional vector control methods of traction motor, which can′t meet the need of high speed torque′s saltation. Under the mode of fixed voltage amplitude of the traction converter, the method presented can achieve the real－time control of high speed torque′s saltation of the traction motor, through the way of combining the high－speed change of converter′s voltage phase with the modified value of the magnetic flux feedback. The results are achieved through theory analysis and simulation experiment, which proves the feasibility and advantage of the control method.

Key words: traction motor, fixed voltage, vector control