基于X射线的液位检测系统的设计

发布时间：2018-08-13 16:31

【摘要】：液位检测是工业生产中的一个非常重要环节,在石油、食品加工、产品封装等领域有着极其重要的意义。本论文采用发展成熟的PLC,结合闪烁体探测器、X射线发生装置和STM32控制模块组成了稳定性较强的液位检测系统,该系统主要针对啤酒、饮料等灌装产品进行液位检测。本文主要研究了可以控制的低能量X射线源(X光管),主要是对灯丝供电电流和加在X射线阴、阳两极间的高电压的控制。为了使X射线源能够稳定地工作,还附加了一些其他监控量:高压的供电电路以及灯丝供电电路的开关时间长短的控制。高压直流电源主要使用的是开关电源技术,高压和灯丝供电使用的是不同的拓扑结构,使用PWM波占空比来控制电源输出电压,还设计了反馈控制环路来提高电源稳定性。为了工作人员免受X射线的辐射,选用远距离控制射线的方法,所以选用了微控制器STM32103VET6作为下位机的主控制器芯片,并且在此微控制器上编写程序来控制射线。选用RS-485串行接口和上位机通信,上位控制软件在labVIEW环境中开发。自主设计了脉冲信号处理电路,并且对脉冲信号放大电路作了简单设计;针对PLC高速计数器HSC4(HSC5)做了脉冲计数测量实验;完成了 PLC对脉冲计数数据采集与处理程序,分析了系统的检测精度。
[Abstract]:Liquid level detection is a very important link in industrial production. It is of great significance in the fields of petroleum, food processing, product packaging and so on. In this paper, a stable liquid level detection system is composed of a mature PLC, a scintillator detector X-ray generator and a STM32 control module. The system is mainly used to detect the liquid level of beer, beverage and other filling products. This paper mainly studies the control of the low energy X-ray source (X-ray tube) which can be controlled. It mainly deals with the control of the filament supply current and the high voltage between the negative and the positive poles of the X ray. In order to make the X-ray source work stably, some other monitoring parameters are added: the control of the switching time of the high voltage power supply circuit and the filament power supply circuit. The high voltage DC power supply mainly uses the switching power supply technology. The high voltage and filament power supply uses different topology. The PWM wave duty cycle is used to control the output voltage of the power supply. A feedback control loop is also designed to improve the stability of the power supply. In order to protect the workers from X-ray radiation, the method of remote control ray is used, so the microcontroller STM32103VET6 is chosen as the main controller chip of the lower computer, and the program is written on the microcontroller to control the ray. RS-485 serial interface is selected to communicate with host computer, and upper control software is developed in labVIEW environment. The pulse signal processing circuit is designed, and the pulse signal amplification circuit is simply designed. The pulse count measurement experiment is done for the PLC high speed counter HSC4 (HSC5), and the program for collecting and processing the pulse count data by PLC is completed. The detection accuracy of the system is analyzed.
【学位授予单位】：山东科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TP274;O434.19

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