In desiging the practical plasma application chamber for the treatment of textile material of commercial size, extra consideration is required on the structure and plasma power source of the chamber beacuse any mismatch between the system tends to generate high-reactive voltage which likely leads to the breakdown of the complete power system.
In this paper, the author analysis the electrical characteristics of low temperature plasma introduced by abnormal glow discharge and derives a practical method of minimizing the effect of reactive component. In order to prevent destructive effect of reactance, the choosing of the lowest usable frequency is required. The author calculated that the power frequency of 24㎑ is the lowest frequency that can be used without impairing discharging efficiency. By choosing the frequency around 300㎑, together with a cage-shaped circular electrode with a feedback oscillator amplifier, the author successfully removed surge effect with the efficiency of better than 0.98. A complete electric system, including the electrode assembly and a 50 ㎾ high frequency power source, has been desigend and manufactured based on the analysis, which are assembled into a practical large size plasma treatment system. A serise of measurments made on the electrical system fairly matched with the results of theoretical analysis. The plasma treating facility composed of the main chamber(17.5㎥ capacity), the vacuum system, the cooling system and the electrical system has successfully treated the PET material with a speed of 4/m/min.
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