CFD Simulation and Energy Balance of a High Voltage Gas Circuit Breaker

High-voltage circuit breakers (HVCBs) are critical components in power systems. They safely isolate and connect electrical networks. Their primary function is to open or close circuits, controlling electrical current flow under normal conditions and preventing damage during faults. HVCBs interrupt currents from very small values up to the maximum rated short-circuit current. The interruption process uses arc energy to generate gas pressure, which is necessary for extinguishing the arc and preventing re-ignition. The residual arc energy is dissipated through heating and ionization of the surrounding gas, vaporization of metals from arcing contacts, and ablation of nozzles. Understanding the energy balance in an HVCB is crucial for designing efficient and reliable circuit breakers. This involves determining how the arc energy is distributed among the various dissipation mechanisms. This work investigates the energy balance of an HVCB using computational fluid dynamics (CFD) simulations. The simulations are performed for a power test duty with 100% of the short-circuit current (T100a). The results show that the energy balance is complex and depends on several factors and estimating it can highlight necessary design changes to enhance performance. By using CFD simulations and understanding the energy balance within an HVCB, engineers can develop more reliable and efficient circuit breakers that can meet the demands of modern power systems.