Research On Key Problems Of Experimental Platform For The Pressure Sensor In Deep Ocean

The deep-ocean pressure sensor is a important tool of explorations in deep ocean. In order to make it meet requirements of high pressure’s measurement in deep sea, and realize measurement of small pressure’s change, the deep-sea pressure sensor needs a experimental calibration platform.Feed system’s precision of experimental platform, relational expression between pressure cylinder’s pressure and the piston rod’s feed displacement, and-delay and pressure fluctuation of the output signal with respect to the input signal during the experiment are direct reasons for affecting accuracy of the pressure, and key problems of the experimental platform. This paper mainly focuses on these three aspects of problems.Firstly, main errors of experimental platform (including geometric errors, return errors, load errors, deformation errors of pressure cylinder system, and thermal errors) were classified and relational expression between feed errors and geometric errors、 return errors、load errors was summed up according to errors’ synthesis principle. The relationship between cylinder pressure’s pressure and the piston rod’s displacement was obtained based on the liquid compressibility and analysis of the deformation errors of the system of pressure cylinder under pressure. Then, feed errors and return errors of the experimental platform were measured through the experiment, and reasons of these two errors were analyzed.The experimental platform is a closed loop feedback control system. Response performance of this system were obtained by establishing the mathematical model of the system and analyzing the step response of the system through MATLAB/Simulink. In order to get the relationship between the input and output pressure of the pressure cylinder, simulation analysis of the whole experimental platform were carried out by AMESim software, and rules between the input and the output pressure of the pressure cylinder were summarized.Through the above analysis, feed errors of experimental platform, the relationship type between pressure and feed displacement, dynamic characteristics of the platform were given, which all provide technical support and theoretical reference for the later experiment of the deep ocean pressure sensor.