Research Of On-line Trace Sodium Ion Analyzer Based On STM32 And ?C/os-?

In recent years,with the country's industrial restructuring of the power industry,small-capacity and low-parameter generator sets have gradually been eliminated,large-capacity and high-parameter generator sets go to the historical stage and become the pillar of the national power industry development.Due to the strict requirements on the quality of water and steam for the thermal system of large-capacity and high-parameter generator sets,the requirements and importance of the performance of online chemical monitoring instruments by various power plants are also increasing.Sodium ion concentration is an important indicator for evaluating the quality of water and steam systems in power plants.It is also an important parameter for identifying condenser leakage and supervising the working state of cation exchangers,therefore,the improvement of the measurement performance of the online sodium ion analyzer has important value and significance for ensuring the safety of the thermal system of the power plant.This paper illustrates the background and significance of localization of high performance online sodium ion analyzers through detailed data and examples.The measurement principle and influencing factors of the solutions of sodium ion selective electrode method are described and analyzed in detail.Due to the shortcomings of the two-point calibration method,a new calibration method based on the combination of fast iterative algorithm and student's t test based on multiple criteria is proposed,and it greatly improved the accuracy of the online sodium ion analyzer in measuring trace amounts of sodium ions.In the design of the instrument analysis flow path,the electrolyte constant pressure injection device and the electrode automatic activation device are added,and it can be completed that the constant pressure supplementation of the reference electrode electrolyte and the periodic automatic or manual activation of the sodium ion selective electrode.The online sodium ion analyzer of this paper adopts a three-electrode system to measure the sodium ion concentration while monitoring the pH value of the solution to be tested.In the design of the hardware circuit system of this paper,the low-cost,high-performance and 32-bit STM32F103 series micro-control chip developed and developed by the company of ST is the core,and the SDWe070C11 C capacitive true color touch screen is used as the human-computer interaction interface.The power supply,minimum system,measurement and detection,communication,valve control and other circuits constitute the hardware circuit system of the instrument.In the design of the software,the ?c/os-III embedded real-time operating system is transplanted,which avoids the shortcomings of poor real-time performance,low reliability and serious CPU waste of the front and back systems.It realizes the embedded real-time operating system apply in the online chemical monitoring instrument of the power plant.Instrument experiments and field operations show that this on-line trace sodium ion analyzer solves the problems of low automation degree and poor accuracy of measurement results of the existing domestic online sodium ion analyzer,and compared with the imported online sodium ion analyzer,it also has the advantages of small maintenance and low operating cost,it can realize stable and accurate online monitoring of trace sodium ions in water and steam systems of thermal power plants,and has broad market and application prospects.