Electrical strength of air containing ozone and nitric oxides produced by intensive partial discharges

Internal arcing test results of gapped SiC arresters are presented. During a test in which the arrester is exposed to internal arcing, the positive impulse breakdown voltage increases. Measurements made with a model arrangement indicate that the increase in the electrical strength of gas is higher for positive than for negative impulse polarity. When the internal discharges extinguish, recovery processes occur. Additional phenomena that can cause changes in the electrical strength are discussed.