【作者】 徐沾伟；

【导师】 郑贵林；

【作者基本信息】 武汉大学 ， 通信与信息系统， 2012， 博士

【摘要】 水质是指水和水中所含杂质共同构成水的物理、化学和生物学的综合性质。水质的特性决定了水质传感器区别于传统传感器,具有多样性、跨学科性等特点。随着人为污染日趋严重,工业生产释放的废水、废渣,农业生产使用的农药、化肥以及大量的生活污水和垃圾排入水中,水体特征更加复杂,导致水质传感器的研究更加复杂。随着微电子技术的迅猛发展,以及各种新材料、新元件、新工艺及新技术的引入,水质传感器技术得到了快速发展。针对目前水质传感器仍然存在的一些问题,本文研究和实现了一种新型多参数在线水质传感器。本文的主要研究内容概括如下：(1)研究了水质传感器系统的三个关键问题：可靠性、低功耗、自维护。从功能与系统角度分析水质传感器的可靠性问题,提出了硬件、软件设计以及系统构建的具体可靠性措施；在传统低功耗技术基础上,提出了“谁工作谁上电”的电源管理策略,进一步降低了设备功耗：针对水质传感器的使用环境,提出了微型增压泵与超声脉冲扫频相结合的方法,实现了水质传感器的自维护功能。(2)深入研究了pH、溶解氧、电导率、水位、水温五项水质参数测量原理,改进并创新了相关参数的测量方法。采用电位法测量pH,采用电流法测量溶解氧,采用对称脉冲法测量电导率,采用隔离膜片压力传感器测量水位,采用数字温度计测量水温。(3)实现了多参数水质传感器的结构设计与硬软件设计。根据水质传感器组成部件采用紧凑全密封的柱形分段壳体结构。硬件上采用模块化设计,根据功能划分为主控模块、pH测量模块、溶解氧测量模块、电导率测量模块、水位水温测量模块与自维护模块,各模块相互独立拥有自己的MCU,模块之间通过RS485总线连接。软件上实现了主MCU与分MCU的嵌入式软件设计以及传感器测量配置软件的设计。(4)设计了试验平台,模拟传感器工作的极端环境,对传感器电源、多个参数测量精度、温度稳定性等性能参数进行试验与论证,对试验过程中出现的问题进行了分析与处理。(5)分析了广州从化太平场水文站水质监测数据,并得出了相关结论。基于以上研究内容设计的多参数水质传感器已完成系统设计到原型河流试验,实践表明,达到了预期目标,实现了五参数的在线稳定测量。更多还原

【Abstract】 Water quality refers to water and impurities in water together constitute water’s physical, chemical biological and integrated nature. The water quality characteristics determine the difference of water quality sensor and conventional sensor. It has diversity and interdisciplinary. The man-made pollution is increasingly serious. Today, water and waste released by industrial production, pesticides and fertilizers used by agricultural production, a lot of sewage and garbage are drained into water. Water feature is much more complex than ever. Therefore, the water monitoring sensor is even more complex. In order to fit the increasing demands of the water rescource management, a new noval multi-parameter online water quality sensor is presented in this paper.In water quality sensor:three key issures are system reliability, low power consumption and self-maintenance. Perspectively, reliability problem of water quality sensor is closely relative to hardware, software, system structure design as well as its manufacture process. So perfect comes from detailed precision.The main contents and contributions are as follow:Firstly, To reduce energy consumption, a functional method, only working elements are power supplied, while turn off others which only work in cycle.Secondly, To realize self clean the sensors’ability, a pump driving recurrence washing structure is studied and implemented and a ultrasonic frequency pulse sweep is pretended against the microorganism hanging on the sensors.Thirdly, five of parameters of water quality sensors are studied in detail. They are pH, dissolved oxygen, conductivity,water level, water temperature. Creative measurement methods are studied, such as electronic potential is used for pH measurement, electronic current is used for dissolved oxygen measurement, symmetric pulse method is used for conductivity detecting, isolation diaphragm pressure sensor is used for water level measurement.With the achievement above, a systematically designed multi parameter sensor is developed and described in the paper. It is composed of amould shell in a compact, sealed, cylindrical, segmented shape in which five modules are integrated, they are main control module, pH measurement module, dissolved oxygen measurement module, conductivity measurement module, water level and temperature measuring module as well as the system designed for self maintenance. Each module has an independent MCU. All the modules are connected via RS485bus.It is known, the test and study of any sensor at the simulated extreme experimental environments are important, the test and demonstration of the sensor’power, accurancy, temperature stability for each integrated sensor are also described in chapter? A compact5parameter water quality transducer has been installed in Taiping Hydraulic Station, Chonghua City, Guangdong Province since July,2011. Analysis and observation of the transducer is indicated in chapter? The transducer works well until present time.更多还原