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Abstract—This paper develops a flux-linkage estimator using voltage model in stator reference based on an improved integrator with DC-offset PI-correction loop having the reference flux magnitude in the correction error. The DC-offset and drift from acquisition channels and the flux-vector initial error are canceled. A phase locked-loop state estimator extracts the speed and position from the estimated rotor flux. This robust solution can be applied in all AC drives with sinusoidal flux distribution in wide speed range, including sensorless control. A sensorless DTC is investigated for both PMSM and IM drives. Simulation results for PMSM drive and also experimental results for IM drive prove high-dynamic performances in large speed range step reversal, for zero to rated load-torque step. Index Terms—Direct torque control, flux estimator, integrator with DC-offset correction, sensorless control I