Quantitative Evaluation of Electrical Life of AC Contactor Based on Initial Characteristic Parameters

In terms of estimating the ac contactor's electrical life, a new method based on initial characteristic parameters is put forward in this article. First, the characteristic parameters of the contact voltage in the closing stage and the arcing energy in the breaking stage are selected to extract their statistical indexes due to different stages in the contactor's action, and the correlation between the indexes and electrical life is calculated by means of the Spearman rank correlation coefficient. Next, the electrical life evaluation indexes corresponding to the stages of closing and breaking are computed according to the weighted Euclidean distance calculation; the electrical life comprehensive evaluation index is presented by secondary fusion of the abovementioned indexes. Finally, a life prediction model based on unitary regression is established to evaluate electrical life with the predicted input of the comprehensive evaluation index. The results have displayed that the proposed method succeeds in quantitatively evaluating the electrical life of an ac contactor.