A test method of winding deformation excited by pseudorandom M-Sequences — Part II: Experiments and outlook

In order to implement the test method to detect winding deformation excited by pseudorandom binary M-Sequences (The M-Sequence method), a detecting instrument for winding deformation synthetically based on the M-Sequence method and Frequency Response Analysis (FRA) is developed. Three kinds of the artificial failures aimed to simulate winding deformation were set in a pie-type winding. Comparative experiments between the M-Sequence method and FRA were carried out, and the results show that frequency response and statistical characteristics of the M-Sequence method are consistent with those of FRA in the common frequency band, which proves that the two methods have the same accuracy in terms of frequency response. Transfer function coefficients obtained by the M-Sequence method as well as changes in the map of the poles and/or zeros can also indicate winding deformation. The experiments confirm that the M-Sequence method is a feasible approach for identifying winding deformation. Moreover, the on-site experiment shows that frequency responses obtained through the two methods are coincident in the common frequency band, while differences exist between the poles/zeros obtained by transfer function and peaks/troughs in the frequency response curve obtained by FRA. The presented study of this new method demonstrates that it has some advantages over FRA and lays the foundation for further practical applications.