| Ozone is a kind of strong oxidant which has high efficiency without bis pollution, so it is widely applied to the disposal of the tap water, municipal sewage, domestic fecal sewage and industrial sewage. With the development of society and economy, the demand for the ozone technology is more and more apllied to the disposal of the tap water and sewage in our country. But the technology of home-made large-capacity ozone generator is relatively backward, for example, the generator has smaller capacity, the productive outlays is higher, the degree of automatization is lower. Especially the ozone generator which can online measure the ozone concentration has not emerged, so the ozone generator can not realize the automatization in the course of ozone production. On one hand, if the output is fewer, it doesn't meet the demand for the disposal of the tap water and sewage. On the other hand, if the output is excessive, it wastes the electric energy and increases the productive outlays. So the research of the online automatic measuring system of ozone concentration is important and valuable, which can improve the level of the home-made large-capacity ozone generator. This thesis studies the mathematic relation between the ozone concentration and the applied voltage in the course of ozone which is generated by dielectric barrier discharge. The relation offers the bases for the ozone generator realizing the closed-loop control. This thesis designs the automatic system that can online measure ozone concentration, the system is based on the 89C51 single-chip and adopts the ultraviolet ray absorbing law. This system not only can realize the function of online measuring the ozone concentration and output, but also realize the function of online measuring the ozone temperature and velocity of flow, which can deal with the trouble and give an alarm when the air source system or the cooling system is failure. Furthermore it can communication with the CPU of power supply via the RS485 interface, which can realize the closed-loop control for ozone generator.The main content of the thesis is following:(1) The chemical change that the air produces the ozone in manner of dielectric barrier discharge is analyzed, and the calculation formula that the number of ozone molecule which is produced by the unit discharge energy is found out. Based on the equivalent circuit of the ozone generator, the calculation formula of the ozone concentration and the mathematics relation expressions between the ozoneconcentration and applied voltage under certain conditions is proposed, which offers the bases for the closed-loop control of ozone production.(2) Three kinds of operation principle which measures ozone concentration at present is recommended: KI titration law, ethylene giving out light law and the ultraviolet ray absorbing law, and these method's own pluses and minuses is compared. The ultraviolet ray absorbing law is suitable for the automatic system which online measuring ozone concentration is found.(3) The configuration of the automatic system which online measures ozone concentration is designed. The system is made up of three parts: lamp-house subsystem, light subsystem and circuit subsystem. Lamp-house subsystem is made of the mercury-arc lamp which radiates in the low air pressure and effects luminosity stabilization, and the dimmer which is a kind of bandwidth filter. A measuring method which adopts single ray irradiating ozone concentration into the light subsystem is introduced. In the course of measuring luminosity, temperature and velocity of flow, the technology which gets rid of the extreme value and calculates the average value is used. A new kind of circuit which can realize linear transform for the temperature sensor is designed.(4) According to the means of modulization and structurization the programme is combined to write. A few of anti-jamming measures which combines hardware with software is used, such as the double integral A/D converter, the restraining of power interferes, digi...
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