Arc voltage characteristics of high current fault arcs in long gaps

This paper describes the arc voltage characteristics of high current arcs simulating fault arcs on 500 kV class transmission lines and the simulation result of the 50 kA rms class fault arcs. A high power arc test was carried out and the arc voltage in a 3.4 m gap and the voltage of the arc jet near the electrode were measured. The voltage gradient of the arcs and arc jets and the voltage-current characteristics of arcs were investigated. The test results showed that the voltage gradient of the arc jet was larger than that of the arc column. The high current fault arc voltages were calculated using numerical arc models and the arc parameters for the numerical arc model of 50 kA rms class ultra high current arcs were investigated. The calculated values were in good agreement with the measured data.