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硕士论文-原油含水率智能检测的研究，正文共66页。
【摘要】 原油含水率的准确测量对原油的安全开采、储运以及后期的加工等环节起着至关重要的作用。由于长期的开采,我国大部分油井已经进入中高含水率时期,因此根据我国原油自身的特点研究出新的原油含水率检测方法,研制出高精度新型传感器,开发出更精确、稳定以及测量范围广的仪表,具有重要的意义。微波是一种频率很高的电磁波,由于水的介电常数比纯油的介电常数大很多,所以经过油水混合物后微波能量的衰减主要是由水分引起。通过测量微波信号能量的衰减量来测得原油的含水率,这就是微波透射衰减法测量原油含水率的原理。该方法具有测量精度高、抗干扰能力强、可靠性好等优点并且满足在线连续测量的要求。因此本文选择用微波法实现原油含水率的智能检测。本论文主要的设计内容包括微波测试系统、信号处理系统、单片机系统。微波测试系统改进了传统单通道测量的方法,采用测量通道和参考通道双通道的测量方式,实现自动定标的目的。由于微波频率很高,直接分析微波能量的衰减量来测得原油的含水率将很难实现,而用1KHz方波信号将其调制,分析解调出的低频方波信号幅值的变化来测得原油的含水率将很容易实现,因此设计了一套调制解调微波测量信号处理系统,包括选频放大器、整流滤波电路、A/D转换,实现微波测量信号的检测。单片机系统中采用STC89C52单片机,通过对A/D的控制完成数据的采集和处理；并通过对温度传感器的控制实现温度补偿；可通过控制系统中参考通道的数控衰减器实现自动定标零点,即实现自动定标调节的目的;最后通过液晶显示出原油的含水率。本实验装置可对10%-60%的中高含水率模拟原油油品进行测量,测量误差小于2%。
【Abstract】 Water content in crude oil plays a vital role in crude oil secure exploiting,storage, transportation, subsequent process and so on.Because of long-time exploit,oil wells in our country have already come into a high water content period. Based on our country crude oil character, a new method to measure water content in crude oil is studied. It is important to develop new sensors, exploit instruments with high accuracy, stabilization and large measure scope. Actually there are many methods to measure water content in crude oil,for example density method, shortwave absorb method, capacitance method, microwave method.Microwave method is selected in this paper to measure water content in crude oil.Microwave is a kind of high frequence electromagnetic wave, because the permittivity of water molecule is more larger than pure oil, the power attenuation of microwave is mainly absorbed by water when microwave pass through oil with water. Though measuring microwave attenuation the rate of water content in crude oil is known, which is the principle of microwave method measure water content in crude oil. This method can meet the demand of online and sequence measure and has some merits, such as strong resist interfere, good reliability, high accuracy and so on. So this paper select microwave method to realize measure water content in crude oil.The main design of this paper are microwave test system, signal processing system, MCU system. Traditional single channel method is improved in this paper,double channels including measuring channel and reference channel are used to achieve automatic calibration. Because of microwave is high frequency, it is difficult to measure the moisture content in crude oil directly by the analysis of the attenuation of microwave energy. Instead, it is simple to use a 1KHz square wave to modulate it and analysis the amplitude changes of low frequency square wave after demodulation to measure the moisture content in crude oil. So this paper designs a modulation and demodulation microwave measurement signal processing system, including selected frequency amplifier, rectifier circuit,filter circuit, A/D converter, realize microwave measure signal detect. STC89C52 is used in MCU system to control A/D converter to collect and process data.Temperature compensation is achieved by controlling temperature sensor and numerical control attenuator is used to realize automatic calibration zero, such to realize automatic calibration adjust. At last LCD display is used to display water content in crude oil.This experiment device could accurately measure high water content in simulate crude oil sample from 10% to 60% and the measure error is less than 2%.
【关键词】 微波检测； 定标调节； 含水率；
【Key words】 Microwave Detect； Calibration Adjust； Water Content；