Study On Technology Of Zoning Excitation In Scaled Plasma Source Of DBD

Non-equilibrium plasma can be generated by dielectric barrier discharge (DBD) at atmospheric pressure. It is used in many fields such as environment protection, microelectronics industry, modification of material surface, etc. So the research on DBD has been paid more attention in the field of plasma science. Although, it has got certain result in some aspects by the middle and small plasma in DBD. But existing plasma resources can't be used in situation of needing scaled plasma because of their limited scale and efficiency. At present, the main problem of hindering the development scaled DBD plasma source is that the frequency of system operation is low; the power output is hard to improve. In order to developing the efficient scaled plasma source, this paper combines with "the support projects of science and technology ministry" (No. 2006BAC11B06) and "the talents-support plan of education ministry in new century" (No. NCET-05-0296) focuses on the research of excitation technology on scaled DBD plasma source and the simulating of single micro-streamer of DBD.The micro-streamer discharge is the main work model of scaled gas phase DBD plasma chemical reactor. Beginning from the modular construction of micro-streamer, equivalent circuit of single micro-streamer is established in this study, and simulating the equivalent circuit by Protel, conclusion as follows: the bigger the distributed capacitance of single micro-streamer, the higher the peak value of single micro-streamer, so more micro-streamer will be got at unit area when dielectric medium that the value of relative dielectric constant is higher is used. When the value of series capacitance of gasp and dielectric or resistance of equivalent circuit is higher, the peak value of single micro-streamer diminish, pulse width become wider. As the scale of DBD plasma source become larger, it makes against forming micro-streamer and must be ameliorated.Non-equilibrium plasma chemical reaction system is composed of large quantities micro-streamers, dimension amplification effect restrict the improvement of performance in plasma source. The resonance effect of leak inductance of transformer and equivalent capacitance of generator is the key matter. So based on this point, a new excitation technology-zoning excitation technology is brought forward, the whole generator is divided arrays and an array is drove by a high frequency transformer, all transformers are adjusted and controlled by a inverter. It proves that the resonance frequency and discharge power are improved under the zoning excitation technology by experiment; and it lays a technological foundation for enhancing the performance of scale plasma source in DBD.