Determination of the angular position of the rotor of a synchronous motor by connecting a high-frequency signal in the excitation winding

The article deals with sensorless method for determining the angular position of the rotor of a synchronous motor by means of superimposing a high-frequency signal. The scheme of the laboratory stand for the experiment to determine the angular position without the use of the position sensor was made. A technique for determining the angular position of the rotor with an accuracy of 30° was described. The logic diagram for its implementation was presented. The derivation of the formula for the calculation of the angular position of the synchronous motor rotor was presented. Findings during the experiment for determining the angular position sensorless were analyzed. Conclusions to reduce the cost and size of the drive system and increase its reliability were presented.