<p>The research outlines the outcomes of utilizing methods based on a mathematical model of the motor for sensorless control of permanent magnet synchronous motors (PMSM) in the medium- and high-speed range using different strategies. The Back-EMF observer utilizes stator voltages, stator currents, and a mathematical model of the motor. An estimator, like a phase-locked loop or an Atan function, is used to determine the rotor speed and position. As the accuracy of these estimates has a direct influence on the quality and dynamics of the sensorless control, precise Back-EMF signal observation is paramount. Furthermore, the research demonstrates the implementation of sensorless control in an actual motor. The results are divided into four sections, comprising steady states, transient states, states with load torque and robustness against parameter changes. In order to fully explore the theory and its real-world applications, the simulation results are compared with those obtained from measurements taken on a real motor.</p>