Design Of Water Content Detection Instrument For Fine Iron Powder Based On Capacitance Sensor

The water content of fine iron powder is indispensable important price parameters for iron powder commercial trade,so it is of much important significance to measure it in real time and fast.At present,in the process of fine iron powder commercial trade,usually the water content of fine iron powder is measured by the verbal commitments to buyers and sellers,the basis for judgment usually derives from the results of laboratory sampling measurement.Because the credibility and fraud issues exist and the price dependes on the water content of fine iron powder in actual sales process,so there is an important practical significance to the reasearch of real time water content detection system for fine iron powder.In this paper,based on the water content of fine iron powder measurement system of capacitance humidity sensor,it designs the test probe of the water content of fine iron powder,researches the humidity sensitive mechanism of capacitance humidity sensor,and analyzes a variety of influencing factors to water content detection,including a kind of fine iron powder sample,temperature and compaction rate.Based on the humidity sensitive mechanism of capacitance humidity sensor,it designs the testing circuit of water content of fine iron powder,and completes simulation and debug of circuit.At the same time it designs the STC89C55 microcontroller control system of water content detection for fine iron powder,and completes the program and debug of single-chip control system software.It analyses the mechanism of temperature compensation,and defines the influence from temperature on the frequency output,quantitatively gives the method of temperature compensation.It analyses the influence from the water content of fine iron powder on the frequency output,establishes the mathematical model for the water content of fine iron powder and module output frequency of water content detection,analyses the factors affecting the water content of fine iron powder due to measurement data,and establishes the relationship between the water content of fine iron powder and impactive factors by multiple regression.In a variety of methods of the water content of fine iron powder,capacitance becomes the most important method for the simple structure,low cost,and easy used in real time or site testing and so on.The paper designs and achieves the water content of fine iron powder measurement system of capacitance sensor,and analyses a various of impactive factors on system output.The achievement of this paper is that it lays the necessary foundation for future study of the method of the water content of fine iron powder,as well as provides a theoretical basis for improving the performance of water content of fine iron powder detection system.