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In Industries, AC motors are preferable to DC motors because of their commutatorless and brushless operation. Permanent Magnet Synchronous Motor (PMSM) is familiarizing for the reason of its less weight and high efficiency. To get the fast dynamic performance and also the maximum torque per ampere in AC motors it is necessary to do Field Oriented Control (FOC). FOC in PMSM can be achieved by regulating the resultant stator current vector i.e. vector addition of three-phase stator current and rotor magnetic flux angle at 90 degrees. Initially, the rotor flux angle ⊖ will be sensed by the rotor position sensor. Then, the resultant stator current vector will be continuously regulated to 90 degrees with respect to the rotor flux angle. The stator currents in the rotating reference frame are direct axis (d-axis) or flux component current id and quadrature axis (q-axis) or torque component current iq. The currents id and iq are coupled in the stator windings and there will be significant distortion in id when there is a change in the iq and vice-versa. If the speed of the PMSM increases, then the torque component current iq and hence the distortion in the flux component current id increases. Prior researches solved this issue of distortion had failed to denote the amount of distortion in the current id when there is a change in the speed or torque component current iq. In this paper, the equations for the d-axis and q-axis coupling terms were derived and PSIM simulation of FOC was carried out with d-q axes decoupling using feed-forward compensation. The stator current id is compared with d-q axes decoupling and without d-q axes decoupling. Moreover, the amount of maximum distortion in current id with d-q axes decoupling and without d-q axes decoupling is calculated when there is a change in the speed of the PMSM from 100 rpm to 0 rpm and also from 150 rpm to 0 rpm. [ABSTRACT FROM AUTHOR]