29 / 2024-03-28 14:19:15

Health status evaluation of low-voltage DC circuit breaker based on the morphological characteristics of arc plate

low-voltage DC circuit,arc ablation trace,morphology feature extraction,health status evaluation

In the breaking process, low-voltage DC circuit breakers inevitably generate arc. Arc ablation will seriously affect health status of circuit breakers. Therefore, this paper proposed a health status evaluation method of low-voltage DC circuit breakers based on the morphological features of arc plate, by analyzing arc erosion trace. Firstly, carry out cyclic operation test of DC circuit breaker, and collect 2-D morphology image of arc plate at a certain interval. Then, visualize these images of arc plate using effective image processing algorithm. The key morphological feature parameters are extracted: 1) Distinguish the color difference between arc track area and other areas through the threshold segmentation method. Thus, the arc track area is extracted and its area is calculated as feature h₁. 2) Extract the material loss area of arc plate after ablation based on unablated image. Thus, the loss area is calculated as feature h₂. Finally, according to the degradation trajectories of h₁ and h₂, they are divided into linear degradation feature and nonlinear degradation feature. This paper established a health status assessment model using both segmented fitting and σ principle. Through example verification, accuracy of this model is as high as 100 %. By analyzing the morphological characteristics of arc plate, the purpose of characterizing circuit breaker's health status is achieved.