Research On Distributed Dust Concentration Network Measurement And Control System

Air quality issues constrain people's living standards.Nowadays fog and haze occur frequently.Dust,as the main cause of haze,has become the focus of research.Cities are always environmental disaster region of dust pollution.The main polluted sources are the car exhaust and construction dust.Dust detection systems for open atmospheric environments such as road traffic and construction sites become one of the research priorities.For solving the above problems,this paper designs and develops a set of dust control system for open atmospheric environments.Firstly,this paper describes the types and hazards of dust particle matter,indicating the importance of measuring and controlling dust concentration.Comparing common used dust concentration detection method with dedusting method,then selecting the light scattering method as a real-time detection method.At the same time,fully researching the performance index of domestic and foreign mainstream light scattering particle matter concentration device.Secondly,analyzing the theory of light scattering.And the principle of Mie scattering is described in detail.And using analyzing result and principle of Mie scattering as theoretical basis.The relationship between the detection signal and the size of the particles is established by analyzing the electrical signal output from the photoelectric detection device,thus achieving the conversion of the particle matter concentration to the mass concentration.For improving the detection accuracy and stability,the double measurement light path scheme is adopted in the design of dust particle matter concentration sensor.Using the spectroscope to measure the variation of the incident light intensity,the light intensity compensation method can effectively eliminate the measurement error caused by the variation of the incident light intensity.Designing sensor conversion circuit and system peripheral circuit,and through the distributed network that consists of GPRS module and MCU,to achieve a wide range of data acquisition and dust controlling.Using the LabVIEW platform to develop the host computer program,to display and to store the data comes from different detection points,to control the dedusting devices in test points,consequently to achieve effective measurement and control of dust concentration in open atmospheric environment.Finally,calibrating the sensor,then determining the proportional constant K,to analyze the data.Sequentially concluding and prospecting the research,putting forward the corresponding improvement measures to the existing problems and determining the direction of future research.