Investigating High Voltage Breakdown Through a Solid Dielectric Via a Coupled Modeling-Experimental Approach

Undesirable gas discharge is often mitigated by coating electrode surfaces with thin (< 1mm) solid dielectric. The additional protection this dielectric layer affords depends on a variety of factors which can include the material’s dielectric breakdown strength, thickness, relative permittivity, secondary electron emission yield, photoemission yield, and temperature, to name a few. Here, we will develop an analytic model for the breakdown voltage between the electrodes that accounts for the dielectric layer in an air filled parallel plate gap configuration. We will present, and compare to the model, experimental results for high voltage breakdown through epoxy coated surfaces for DC conditions, varying several of the relevant dielectric parameters, along with gap length and pressure. In addition, breakdown due to transient insults are often a concern and will be investigated as well.