Simulation study on arc dynamic characteristics of DC contactor under metallic grid sheet
Dynamic characteristics of DC contactor arc have an important influence on contact breaking performance.Based on magnetohydrodynamic(MHD)theory,the metallic grating sheet arc model is established,and the grid sheet sheath assumption is given to simulate the actual working conditions.The arc reignition phenomenon is explained by analyzing the arc temperature,current density,airflow field and other factors,and the effect of different tilt angles of the grid sheet on the arc reignition is studied.Results show that the main reason for arc reignition is the thermal ionization generated by the residual high-temperature gas after arc extinguishing,which promotes the partial discharge and re-breakdown.Changing the tilt angle of the grid sheet can change direction of the airflow field and the Lorentz force.When the angle is 20°,the number of arc reignition is the least and the arcing time is the shortest.
DC contactormagnetohydrodynamics(MHD)arc reignitiontilt angle of grid sheet
万方数据
维普
