抄録
To obtain a rectilinearly channelled surface discharge under atmospheric condition, a needle - thin film - knife edged electrode system was used and a negative impulse voltage to the needle electrode was applied .
The rectilinearly channelled discharge is quite different from the well-known surface discharge. Contrary to the well-known surface discharge, the negative polarity is much longer than that of the positive one and the discharge channel looks like a leader.
The propagation model of the rectilinearly channelled negative surface discharge that consists of a diffusion-type nonlinear partial differential equation and the boundary conditions are summarized. The nonlinear diffusion equation is solved by assuming the applied voltage is constant and using the moving boundary conditions which are the continuity condition of the electric charge and the propagation speed condition. As the result of discussion of the moving boundary conditions we assumed the potential at the channel tip is constant.
In this paper, the propagation phenomena of the channel and the influence of the waveform to the propagation parameters in case of the impulsive voltage are discussed.