In the past several decades, extensive amount of research work has been done to
understand the fundamental characteristics of the electrical breakdown. Breakdown
voltage is a phenomenon where the quantity of an electrical force is required to
transform the electrical properties of an object. Many factors that lead to the
breakdown voltage are still not fully discovered. These factors are including the
physical parameters of the electrodes (sphere, plane, point etc.) and also the
environmental conditions. In electrical power system, high voltage (HV) power
equipment is mainly subjected with spark over voltage. In this study, point electrode
and plane electrode have been used for the experimental study of the short air gap.
The electrodes are vertically aligned. In order to simulate the performance
characteristic of the air breakdown voltage and maximum electric field between the
conducting point and plane electrodes, the electrodes is taken into considered in this
work using FEMM simulation. The air breakdown voltages between the electrodes
(point and plane) are measured by conducting the air breakdown voltage experiment
in high voltage laboratory and corresponding electrical field strength. The electrodes
gap distances are being varied to 5 different gaps which are 5mm, 10mm, 15mm,
20mm and 25mm. In order to achieve maximum strength in such a field, the point of
the highest stress is controlled. From the experiment, it was established that the point
at the electrode that produces maximum electric field is at the point with the smallest
area or width. As for point electrode, the smallest area is at the angle of the electrode.
Besides, it shows that the electrical breakdown characteristic is affected by the
strength of the impulse voltage. Higher gap distance between the electrodes will
result higher breakdown-impulse voltage while higher breakdown-impulse voltage
will produce higher field intensity