Research On Synchronous Data Acquisition And Motion Characteristics Of DC Rotating Arc

As an indispensable electrical component in people’s daily life,DC switch has been widely used because of its excellent performance,simple structure and low cost.However,with the rapid development of science and technology in recent years,higher requirements are proposed for its performance.How to quickly extinguish the arc and improve the reliability of electrical appliances has become the focus of current research.Therefore,it is of great theoretical and practical significance to study the motion characteristics of DC arc under rotation separation for shortening the arcing time,improving the service life and reliability of DC switch.In order to study the influence of rotation separation on the motion characteristics of DC arc,a synchronous data acquisition platform of rotating arc is designed and set up with different medium in this thesis,for carrying out arc-pulling experiments under different contacts motion respectively.The arc morphology,arc root displacement and energy distribution are analyzed in detail,combined with Zhang Zhengyou Calibration Method,the image processing technology and the feature information extracted from the collected arc image.The result of research shows,under the rotating separation mode with air,there is more metal vapor in the gap at the initial stage of arcing,which increases the arc brightness and enlarges the arc high temperature area.After entering the middle stage of arcing,the rotating motion causes the dislocation of the cathode and anode arc roots to promote the splitting of the cathode arc root,while the arc column frequently "oscillate" in the space to promote the diffusion speed of the particles around the arc column,and the rising speed of the arc voltage is accelerated,the higher the rotate speed,the more obvious the phenomenon.When the rotation speed is kept constant and the linear speed is increased from 0.6m/s to 0.7m/s,the dislocation of the cathode and anode arc roots are more obvious,with the increasing of the splitting frequency of the arc root.Besides,the opening distance is larger and more air pours into the gap at the same time,which increases the contact area between the air and the arc column and further accelerates the loss of arc energy.When the plate contacts are used for rotary separation experiment with vacuum medium,the result of research shows that the diameter of the arc root and the brightness of the arc column increases obviously at the initial stage of arcing.At the middle stage of arcing,with the frequent split of the arc roots,faster energy loss rate,faster area diffusion rate in the middle and low temperature area of the arc,it needs shorter time for the arc to transform to diffusion state.After the contact is replaced by the magnetic control cup contact,there is obvious increasing of the number of arcing points at the initial stage of arcing,more dispersed distribution of arc-starting points under the rotating separation,and the dispersed arc-roots eventually converges into a larger arc root.The arc area continues to rise during the period,followed by the rapid movement of the arc root on the contact surface,which results in the frequent changes of the brightness of the captured arc image and "flickering" phenomenon.