Numerical Simulation of an Explosively Driven HVDC Circuit Breaker

High Voltage Direct Current (HVDC) circuit breakers have to suppress high values of currents at high voltages in absence of current-zero points. This makes the arc interruption more severe than the case of conventional AC networks. For circuit breaking in HVDC networks, a capacitor-inductor set has been inserted in parallel with the circuit breaker to inject reverse current to the interruption chamber and create the artificial current-zero points. In this paper, a novel method for reverse current injection has been proposed in which a high current pulsed power source (Helical Flux Compression Generator) has been employed to generate the opposing current. Numerical simulation of high-current arc in case of HVDC circuit breakers has been presented. For this purpose, the MHD equations describing the behavior of the DC arcs are jointed to the circuit equations of Flux Compression Generator which is coupled to a simple HVDC network. The results indicate that the explosively driven current injection set can make the current-zero point properly and lead to successful interruption of DC current consequently. This method needs much less volume and cost in comparison with the parallel capacitor-inductor sets.