This paper solves the problem of position tracking for a permanent magnet synchronous motor when the angular velocity is not measured and all the parameters of the dynamic equations are unknown. The mathematical model is expressed in the reference fixed to the stator. The adaptation algorithm gives a degree of robustness to the control scheme since it enables one to identify the motor's parameters under the hypothesis of persistent excitation, which is always satisfied when the unknown parameters are only the stator resistance and the load torque. The identification is exponential in these cases. Moreover, it is shown that the closed-loop trajectory corresponding to the nominal parameter values is not influenced by variations of stator resistance and load torque. The performances of the proposed controller are compared with those of a controller which solves the tracking problem with an observer for the angular velocity, designed on the basis of the motor's nominal parameters.