Simulation of the Venting Configuration Effects on Arc Plasma Motion in Low-Voltage Circuit Breaker

A 2-D magnetohydrodynamic (MHD) arc model is developed to simulate the influence of the venting configuration on air arc plasma motion in a low-voltage circuit breaker. It is demonstrated that the fully closed back venting is helpful to accelerate the arc motion due to the propagation of a pressure wave. Side- and central-type front-venting configurations are also compared. It is found that the arc velocity is higher, and yet the probability of reignition is increased for the central-type front venting, as a consequence of differences in the current density distribution. Using an arc chamber with different venting configurations, short-circuit interruption experiments are carried out. These verify the arc reignition trends predicted in the simulations.