A method for speed-sensorless identification of two-mass-systems

The focus of the present paper lies on the identification of mechanical two-inertia-systems based on frequency response measurement without the need of angular transducers. The calculation of the frequency response is carried out by excitation of the system with Pseudo-Random-Binary-Signals followed by a signal processing procedure utilizing the Welch-Method. Former research has pointed out that this approach leads to reliable, good results with measured signals of the systems current and speed. As actual research tends to the control of variable speed drives without encoders, the paper gives an approach for an identification method using estimated speed values from an observer structure.