Pearson pulse transformer has few solid edges in high electric field region. This type of construction prevents accidental flashover damage to the transformer due to poor oil quality or overvoltage beyond the typical 50% to 100% safety factor built into the transformer. The deliberately weak region lies between the high voltage corona ring and the core. These are metal surfaces, and the flashover between them has a negligible effect on the surface, even with the energy involved in a high power linear pulse generator.