This paper proposes a method for suppressing the fundamental and 6th-order oscillations in the estimated position of the position sensorless control of concentrated winding permanent magnet synchronous motors (PMSMs) with all-pass filters. In general, the DC offset in the current or voltage sensor causes the fundamental oscillation in the estimated position. In addition, the 6th-order oscillation in the estimated position is emphasized partically for the stator winding with the concentrated structure for PMSMs. To address these issues, this paper proposes the reduction of these oscillations with the assistance of the flucuation of the estimated flux amplitude and its delayed utilization. Finally, some experimental results show the feasibility and effectiveness of the proposed method.