Studies of Electrical Characteristics and Numerical Simulation of Surface Dielectric Barrier Discharge
|Course||High Voltage and Insulation Technology|
|Keywords||Surface Dielectric Barrier Discharge current characteristics chargeaccumulation circuit equivalent numerical calculation|
Dielectric Barrier Discharge (DBD) which is also called silent discharge can produce non-equilibrium plasma at normal atmosphere. Now it has been used and studied in broad area such as Ozone synthesis, flat panel display, environmental protection, medical sterilization, et al. Surface Dielectric Barrier Discharge (SDBD) is a new kind of DBD. Besides the above normal characteristics, it can be used in air flow control at norm atmosphere. SDBD can transfer electrical power to kinetic energy of the air without mechanical moving parts, which avoiding the traditional mechanical control devices’complex structure, noise, vibration, easy to wear and breakdown, and has a broad development prospects in many aerodynamics areas such as aircraft movements and wind power generation. In a word, SDBD has an important application value in the future.In this paper, the SDBD experimental platform is built up first, and then we study the current characteristics of three cases, such as symmetrical discharge, normal and reversal voltage of symmetrical discharge, point out the effect of electron in barrier surface on the discharge, analyze the effect of voltage and frequency on the discharge power, and analyze the impact trend. Besides the equivalent circuit of SDBD based on the discharge mechanism is built up. After study the equivalent parameters, the formula of discharge power is deduced using the transfer charge in every half discharge period and maintain voltage across air gap in the discharge. The model is proved feasible compared with the Lissajous method.Because the applied voltage is high frequency and high voltage sine wave, the load is capacitive and the power resistance is not zero, the mismatch between the voltage resource and impedance characteristics may happen. In this case the voltage across power resistance will be large enough and voltage across the plasma generator will be small, and the power will be reflected to the voltage resource, casing the low efficiency of voltage resource. In order to solve the problem, parallel matching impedance is required between the voltage resource and plasma generator. This paper builds the equivalent circuit based on the discharge mechanism, and then studies the impedance characteristics at different frequencies. Finally we math the discharge circuit with LR and LCR and receive excellent results.Because of the limitations of the experimental conditions and rapid discharge process, the detailed discharge process can’t be fully understood. So it is an important method to understand it with numerical simulation. This paper simulates the SDBD with air at normal atmosphere by solving the fluid diffusion equation. The model in the simulation contains8particles in the discharge such as O2-, N2-, O2+and electron and16chemical reactions. Based on the simulation results, the paper studies the density derivation process in the discharge, and the movement of electron in the discharge initial period. Finally the paper analyzes the asymmetry discharge compared with the experiment results.