Dielectric barrier discharge (DBD) excimer or exciplex lamps are known as efficient UV and VUV sources but their power supply operates at a high voltage (some kV) and at a frequency of some tens of kHz. Consequently, for industrial applications, DBD lamps need specific power supplies, designed for one lamp geometry and gas filling. We have proposed in [1] and [2] an electrical model of a DBD which can be implemented in an electrical simulation software and can thus be used as virtual load for innovative DBD power supply design. The aim of that paper is to describe the mechanisms involved in the development of an homogeneous DBD and their transcription to an electrical equivalent circuit where the UV flux of the discharge can be estimated.