Abstract:

The structure of high-voltage DC relay is generally very compac. The lack of an arc extinguishing chamber results in high difficulty in extinguishing the arc. In order to solve the existing problems, a new high-power DC relay is developed. Different from the traditional relay, the new type of relay utilizes a motor to drive a gear transmission mechanism to separate the dynamic and the static contacts. The compact transmission mechanism makes the breaking gap enough, which can reach 12~15 mm and effectively break the high voltage and high current. Based on the MHD model, using the Comsol Multiphysics finite element software to establish the new relay two-dimensional symmetrical model, the arcs of the relay under different factors are simulated and the relationship between different factors and the arcing time is analyzed, which can determine the appropriate value range of each factor and also prove the arcing ability of the new relay.

Key words: high voltage relay, DC arc, magnetohydrodynamics (MHD), different factors, arc time