This dissertation addresses the issues of system chattering, rotor position, and speed estimation errors inherent in the use of sliding mode observers for sensorless control of high-speed permanent magnet synchronous motors (HSPMSM). To mitigate these problems, the research introduces the super twisting algorithm as an enhancement to traditional sliding mode observers. This approach replaces the conventional switching function with a stability-compliant function incorporating a disturbance term. Furthermore, the study implements a normalized phase-locked loop for rotor position and speed estimation, superseding the traditional arctangent function method. These modifications aim to reduce system chattering and estimation errors while improving both dynamic and static system performance. The efficacy of this novel approach was validated through comprehensive simulations. Under sensorless control utilizing the second-order sliding mode observer with the super twisting algorithm, when the motor speed tends to stabilize, the speed fluctuation fluctuates between the set reference speed of 30000 r/min ± 20 r/min, and the rotor position estimation error oscillates between 0.035 rad and 0.05 rad. Comparative analysis revealed that the second-order sliding mode observer enhanced with the super twisting algorithm significantly suppressed system chattering compared to traditional sliding mode observers. Moreover, the integration of a normalized phase-locked loop for rotor position estimation yielded reduced estimation errors, enhanced dynamic and static response characteristics, and improved overall system robustness.