A primary transformer is a step-up transformer that takes the line voltage of the AC source and steps it up to a range between 12 kV and 50 kV at 60 Hz (Johnson 4). The efficiency of this transformer is largely dependable on the construction of its core. The iron from which the core is made has to be of a high permeability (amount of magnetization within the iron when immersed into a magnetic field) and a low retentivity (portion of residual magnetic field upon the removal of the magnetizing force).

For the purpose of minimizing the energy losses, it is prefferable to use the straight core. The logic

*…show more content…*

Therefore, by simple logic, one should look for a suitable dielectric material, the area of the plate as large as possible, and the distance between the plates as smaller as possible. Also, one should take into account the breakdown voltage of the used material and maybe some other limiting factors. Figure 2: MMC (Multi-Mini Capacitor)

A spark gap is, as the name indicates, a gap or an open circuit between two wires in the circuit, which becomes short circuited when there is a sufficient voltage build-up on its electrodes. This happens when the capacitor has excerted all its energy on the coil, thus, there is a maximum charge in the coil, which causes a spark that makes a short circuit in the spark gap.

Essentially, a spark gap is a switch between the primary transformer and the primary coil. When there is an open circuit, a capacitor will charge from the primary transformer and, consequently, when there is a short circuit, a capacitor will discharge on the primary coil. Figure 3: Static type spark