Effect of axial magnetic field on surface flashover of cylindrical dielectric solid with gas layer inside

The paper describes the effects of an axial magnetic field on the surface flashover along a cylindrical dielectric solid with a gas layer inside and a back electrode outside. The surface flashover voltage in air depends on the pressure of the gas layer and the magnetic field. For positive impulses, the surface flashover voltage shows a sudden step-shaped reduction at a certain critical magnetic flux density. Beyond this critical value of magnetic field, an aurora-like discharge always appears in the gas layer. On the other hand, for negative impulses, the surface flashover voltage decreases gradually with the increase of the magnetic flux density. The aurora-like discharge either does not appear or sometimes appears irregularly. Semi-empirical equations which can predict the impulse surface flashover voltage in the absence or presence of a magnetic field were obtained