Cryogenic Liquid Level Measurement System In Pulsed Magnetic Field Science Experiment Station

Pulsed magnetic field special experimental conditions need the support of extremely low temperature environment, the traditional ways of level measurement are mostly designed and used for the normal temperature liquid, and most of them are not suitable for cryogenic liquid system in pulsed magnetic field. This study analyzes the principle of traditional liquid level measurement, the function of improved liquid level measurement, the design of the corresponding hardware and software. It also compares the advantages and disadvantages of different designs of liquid level measurement system, and finally put forward the improved and optimal design of liquid level measurement system, which can be suitable for a cryogenic liquid level measurement system in the pulsed magnetic field. Specific research results include:(1) This paper introduces the present situation of liquid level measurement in details. The research and analysis of existing liquid level measurement methods, and the summary of the advantages and the disadvantages of each measurement systems, can make a reasonable reference for the design of cryogenic liquid level measurement system.(2) According to the principles study of the traditional methods and the analysis of defects, the capacitive liquid level sensor has been designed and used for the main problem. Based on the principle of vibration method, the hardware circuit of liquid level measurement mainly consists of a 555 timer and a single chip microcomputer. Under the requirements of the hardware circuit and the system measurement, it completes the software design and program of the capacitive liquid level measurement.(3) There is a discussion about the principle of thermocouple type level measurement and the improvement of the main defects in this design, and completes the design of the heating thermocouple type liquid level sensor. According to the analysis and introduction of this type liquid level meter, it consists of the voltage amplification circuit, analog-to-digital conversion circuit, data processing circuit and constant current source heating circuit, etc. Based on the requirement of the measurement system, there is an optimal design for the relevant software program.(4)Finally, it introduces the tests about these two schemes of cryogenic liquid level measurement system, and compares the results between the former design and the improved design. The conclusion: the measuring accuracy and stability of improved designs are better than the formers, all of they can be suitable for different conditions of low temperature environment.