The Research And Design Of Low Hydrogen Type Electrode Covering Water Content Detecting System Based On Electrical Capacitance Method

Fast,non-destructive,on-line measurement method is of great importance for the detection of water content of low hydrogen alkaline electrode.A novel detection method based on electrical capacitance for detecting water content of low hydrogen alkaline electrode is proposed in this paper,and its detection principle is analyzed and verified.On this basis,a semi-closed cylindrical capacitive sensor is designed,its structure is optimized,and the sensor's structure parameters are obtained.According to GB5117-1995 standard method of measuring the water content of electrode coating,the modified low-hydrogen type alkaline electrode coating water content sensor was calibrated,three different sizes of J707 low hydrogen type alkaline electrode are used as experimental material in this experiment,and the experimental study of the model sensor is carried out.The experimental results show that,when the water content of the electrode is less than 2.4%,the water content of the electrode is similar to that of the electrode of the electrode as the capacitance of the capacitor,and the absorbent saturation point of the electrode is determined by the error analysis.Finally,the detection system is designed based on the sensor of the electrode type,and the detect performance is measured.The results show that the system meets the requirements of the water content of the coating.This research has a very important application value to the non-destructive,fast and on-line inspection of the electrode.This graduation thesis mainly carried out the following four aspects of the research work:(1)According to the principle of water detection,technology and commonly used sensors,the measurement principle is analyzed,and a variety of detection sensors are analyzed and studied.A new method for detecting the water content of electrode is proposed based on that comparative analysis as well.(2)Based on the analysis of the sensor principle and the classification of the sensor,the design scheme of the water content sensor for the low-hydrogen type alkaline electrode is carried out.The structure,the measurement principle and the equivalent model are analyzed and calculated.Then,stress analysis and finite element analysis of the sensor structure parameters,which can be used as theoretical basis of the sensor's manufacture,are given to optimize the sensor' structure.(3)By the calibration experiment of the water content of the electrode,the sensor 's performances are measured.The results show that the sensor can be applied to the detection of the water content of the electrode.In the calibration experiment,the least squares regression equation,the polynomial regression equation and the first linear regression equation were precisly used to find the saturation point of the electrode.(4)The electrode water content sensor detection system based on the capacitance method is designed.Respectively,the system made a detailed introduction from the hardware to software.Among them,a single ampifier with analog switch differential charge and discharge circuit is designed as detection circuit to obtain the sensor's highprecision elecrical capacitance value.At the same time,in the software,a algorithm which can process in the system processor has designed within the range of digital filters.From that,the system's detection accuracy has been improved greatly,and its detection error has been reduced appropriately.