Research on the energy consumption mechanism and characteristics of the gallium indium tin liquid metal arcing process

For high-voltage direct current (HVDC) power grid transmission with higher voltages, the energy-consuming branch of the DC circuit breaker is required to dissipate huge energies of more than megajoules in a short time in the case of a fault and short circuit. The requirements for huge volume and weight are difficult to meet with energy-consuming equipment based on ZnO. In this paper, a new energy consumption method is proposed based on gallium indium tin (GaInSn) liquid metal in the arcing process, and a test platform with adjustable short-circuit current is built. The mechanism triggering GaInSn liquid metal arcing energy consumption is studied. It is found that short-circuit current and channel aperture are the key parameters affecting the energy consumption of liquid metal arcing. The characteristics of GaInSn liquid metal energy consumption are investigated, and four stages of liquid metal energy consumption are found: oscillatory shrinkage, arc breakdown, arc burning phase change and arc extinction. The influence of short-circuit current and channel aperture on the energy consumption characteristics of GaInSn liquid metal is investigated. To further explore the physical mechanism of the above phenomena, a magneto-hydrodynamic model of energy consumption in the GaInSn liquid metal arcing process is established. The influence of short-circuit current and channel aperture on the temperature distribution of the liquid metal arc is analyzed. The mechanism of the effect of short-circuit current and channel aperture on peak arc temperature and the temperature diffusion rate is clarified. The research results provide theoretical support for this new liquid metal energy consumption mode DC circuit breaker.