Dielectric Barrier Discharge Ozonizer Using the Transformerless Single-Switch Resonant Converter for Portable Applications

Abstract

This paper describes the analysis, design, and construction of an ozonizer based on a single-switch resonant converter (SSRC). The main contribution of the work is the removal of the transformer from the SSRC, resulting in much smaller footprint and higher efficiency. High voltage (up to 4.0 $\hbox{kV}_{{\rm p} - {\rm p}}$ ) is achieved using a resonant tank, which comprises of an LC circuit combined with the chamber's equivalent circuit components. Despite the absence of the transformer, the topology is able to generate sufficiently high voltage to initiate and sustain the formation of micro-discharges. Geometrically, the chamber is constructed as a planar type, using muscovite mica as dielectric. The main advantage of using mica is its availability in thin sheet (less than 1 mm), which then allows for the lowering of the initiation voltage. To validate the analysis and design, an experimental prototype of the ozonizer is build. It is found that the ozonizer draws very little power, i.e., less than 8 W with very high ozone yield (over 120 g/kWh at 1.0 L/min). The maximum measured efficiency is 75%. The proposed ozonizer is fed from a low voltage power source (up to 40 V dc) and hence its suitability for a wide range of portable applications.