Establishment And Verification Of The Glow Discharge Plasma Equivalent Circuit Model

For the study of low pressure glow discharge plasma characteristics, the majority of researchers generally use a professional multi-physics simulation software to assist in theoretical research. Simulation can effectively help a comprehensive analysis of the physical model, and their interactions, a variety of games inside the colliding particles and so on. However, there are risks that simulation can not converge, that it needs a long calculation time and other defects. The accuracy and reliability of simulation is heavily dependent on the chemical reaction and parameter setting. This paper proposes a new method which by acquiring voltage and current in the experiment, using the circuit model parameters to match the model components, and then based on the relationship between components and plasma theory,we can further obtain the plasma parameters of interest. This paper has done the following several parts of work:1.Introduces the characteristics of glow discharge plasma. The glow discharge is divided into the positive column region and the sheath to analysis, summarize the characteristics of their own, to lay the theoretical foundation for the equivalent circuit.2.This paper makes in-depth analysis of the low pressure glow discharge theory, the basic theory of equivalent circuit model and combined with the discharge process in our laboratory plasma device builds a glow discharge plasma equivalent circuit model. The experimental apparatus can be divided into a discharge area and the diffusion zone.3.Parameters of components in the equivalent circuit model is to match according to the specific discharge conditions. Through the acquisition of large groups of experiment data of the voltage and current, we can get component parameters then according to the theory of plasma, we deduce the plasma parameters compared with the probe measured data to verify the correctness of model.The results show that the values of plasma electron temperature and electron density derivated from circuit model and the probe measured data had little difference, which it is in the range of allowable error. Equivalent circuit model can accurately reflect the variation of the plasma parameters. It has control of plasma parameters for theoreticalguidance, while providing a rapid diagnostic method of plasma parameters.