Electrical field affected by current decrement ratio at base current

Summary form only given. Recently, the stable supply of electric power is indispensable in a power generation, and a transmission and distribution system of electric power. Therefore, many researchers have researched abnormal phenomenon of power system which is obstacle to the power transmission and distribution. The GCB (Gas Circuit Breaker) has been researched for performance improvement of the arc interruption of abnormal fault current without the fail. The GCB has been researched for the high capacity and downsizing for development of practical use. Because the power network is expanded, the capacity of interruption current increased for reliability. The GCB should interrupt the arc of high current and voltage, shorten the time to interrupt, and become the high capability in order to improve the reliability and practicability. It is important to prevent the insulation of re-ignition and thermal re-ignition of arc after the arc interruption. It is mainly considered that the factor of thermal re-ignition is the arc temperature distribution at current zero. It is considered that the joule heating is related to the formation of the temperature distribution. The joule heating depends on electrical field. The electrical field is affected by the electrical conductivity and current radius at base current. Therefore, it is considered to be determined by the electrical conductivity and current radius of arc with various current decrement ratio is calculated by using the electromagnetic thermal field (EMTF) simulation in the case of rod-plate gap model. As a result, the electrical conductivity and current radius increases with increasing the current decrement ratio. This reason is the temperature increases, and the electrical conductivity as a function of the temperature increases a lot when the transient time is short at the current zero. Therefore, the electrical field decreases after the current decrement.