[Objective] This article focuses on the challenges of stator magnetic field orientation in mover current vector control for the quasi-synchronous operation of a doubly-fed linear motor (DFLM). In high-speed maglev applications, the mover magnetomotive force significantly exceeds that of the stator, making it difficult to obtain accurate stator magnetic field information. Additionally, harmonic injection in the mover current during levitation control presents further challenges. To address these issues, this paper introduced an innovative stator magnetic field orientation method based on a mover-fixed α-β coordinate system, along with a corresponding parameter correction method. [Method] By conducting error analysis and parameter correction, the proposed method determined the mover-side parameters with sufficient precision. This enabled the direct and precise calculation of the relatively small stator back electromotive force in the mover windings, facilitating magnetic field orientation. [Results] The proposed method was validated on a DFLM test platform. The results demonstrated that, with sufficiently precise mover-side parameters, the flux observation algorithm successfully converged the T^-axis component of the stator current to zero, thereby achieving effective magnetic field orientation. [Conclusion] The proposed method accurately determined mover parameters and achieved reliable magnetic field orientation. It was unaffected by harmonic injection in the mover current, maintaining good dynamic performance and ensuring stable magnetic field orientation.