Stastical Variation of DC Corona Pulse Amplitudes in Point-to-Plane Air Gaps

Using a multichannel analyzer, statistical variations of corona pulse amplitudes are studied for positive and negative dc corona in point-to-plane air gaps. It is shown that,en generally, pulse amplitudes follow a Gaussian type of probability distribution. Exceptions to this be havior are observed near the corona onset level, near the pulse-to-glow transition level, or in less nonuniform field gaps. The corona pulse amplitudes are reasonably reproducible for positive corona, whereas, for negative corona, the pulse amplitudes are very sensitive to the applied voltage level and are less reproducible.