Analysis of the degree of sparkling of certain commutator plates of electric machines by the photo-stroboscopic method

Abstract

Analysis of the causes of failure showed that failures of a commutator and brush assembly (CBA) of electric machines make up 10–15% of the total number of failures. Many different methods to control the degree of sparkling of the CBA plates based on the measurement of different physical values and connected with the CBA sparkling processes were developed. The article describes a method of automated analysis of the degree of sparkling of certain commutator electric machine with the use of stroboscopic photo recording of sparkling and computer processing of the photo images of the sparkling plates aiming at obtaining the degree of sparkling for each collector plate. Processing methods of such images using the original OpenCV software library including image identification, classification and obtaining of the integral image and its analysis were considered. The proposed method allows the degree of sparkling under the trailing edge of the brush for each commutator plate to be determined. Determination is carried out for a large number of switching cycles for each brush, which allows statistical error to be avoided; in addition, automation of measurements decreases the influence of human factor on the test result.