Hardware Design Of Open Channel Digital Flowmeter System Based On GPRS And MSP430

The work of this paper is based on the project of “Study on EfficientTreatment of Urban Sewage—Research and Development of a Channel DigitalFlowmeter” supported by Shanxi Province Science Committee. Flow detectionis a very important measure in such fields as industry, agriculture, chemicalindustry, electric power. Recently, flow detection of closed pipeline hasnumerous methods, mature technology and high reliability. However, for flowdetection of open channel, accurate and stable flow measurement is still one ofthe problems due to complex flow change and various water quality structures.Because the fluid located in different locations is affected by differentmechanical impact and indirect measurement value of flow is inaccurate, flowdetection of open channel need to analyze and master the laws of fluid motionclearly. Now, research on the fluid detection of open channel focuses on threedirections:1. Research of new type of flowmeter;2. Improvement of flow detection method such as water level-velocity method;3. Research of new typeof flow tank such as thin-plate weir.This article places emphasis on the combination of the traditional flow tank(Parshall flume) and new type of digital flowmeter. In order to provide accurateand reliable guarantee for the flow measurement, this article regulates waterflow movement to make flow be proportional steadily to liquid level. Thelaboratory develops a channel digital flowmeter and its liquid level precision canachieve2mm. The flowmeter uses microcontroller of MSP430as its coreprocessor, which controls the system to inspect and submit data, coordinates thepower supply and low power adjustment of each circuits and realizes the sorting,storage and analysis of historical data. This article also designs GPRScommunication and solar energy supply system, which provide a reliabletechnical scheme for energy self-sufficiency of digital flowmeter, no-delay dataand real-time data query.In this article, the main work is as follows:1. By studying, analyzing and grasping the open channel flow detectionmethod, the article combines Parshall flume and flowmeter to measure flow;2. This article designs the internal processing circuit of channel digitalflowmeter. And through using MSP430, it realizes the coordinated controlamong internal clock circuit, sampling frequency setting, sampling and storagecircuit, dormancy reset circuit, communication circuit and the power supplycircuit, etc. 3. This article also designs the GPRS communication and solar energysupply system.The experimental results prove that the meter has the properties of workingstability, small errors and strong anti-interference ability. The meter has thepotential of being widely used in agricultural irrigation, water project and otherprojects involving open channel flow measurement.