Research On Temperature Compensation And Overload Protection Center Diaphragm Of High Precision Silicon Differential Pressure Sensor

Diffused silicon differential pressure sensor,as the basic pressure measurement and control instrument,is widely used in industrial process control,internet of things,aerospace,modern biomedical and many other areas.With the improvement of automation and refinement of our control engineering,new requirements of differential pressure sensor in measurement accuracy,measurement stability and measurement reliability are put forward.Sensor industry of our country started later than foreign countries and the gap is large.Especially,high precision differential pressure sensor market is dominated by foreign countries.In this paper,based on the national 863 major project,two issues of practical significance were studied.In order to deal with the affect of temperation on pressure sensor,the temperature compensation algorithm was studied.Under the research of overload protection center diaphragm,the overload protection capabilities was improved.Differential pressure sensor,influenced by the silicon and the temperature characteristics of the packaging medium,when the ambient temperature changes,the sensor output will show large non-linear error.The traditional hardware compensation method and linear software compensation method both are not ideal for their operational difficulties and low compensation precision.The neural network intelligent algorithm has been widely used in the fitting and classification of nonlinear systems because of its superior performance in nonlinear mapping.This paper reviews the application of the existing neural network algorithm in sensor compensation,then proposes an improved radial basis temperature compensation algorithm based on generalized radial basis network,while including fusion clustering algorithms and intelligent optimization algorithms.Based on original generalized radial basis network,new selection strategy are designed for the four unknown network parameters.The number of hidden nodes is determined by the convergence speed and accuracy of the iterative error.The clustering algorithm is used to optimize the network center value.The network expansion value is found by using of intelligent optimization algorithm,and use pseudo-inverse method to calculate the network weights.Three different types of clustering algorithms and optimization algorithms are put into the algorithm,and nine kinds of sub-algorithms are formed.In order to verify the effectiveness of the algorithm,the sensor temperature calibration experiment is designed,the experimental data is obtained,the compensation prediction model is established and the temperature compensation is carried out.The compensation results show that the accuracy of differential pressure sensor output is much higher than that before compensation,and with the continuous optimization of network parameters,the compensation precision is improved.The output of the model verifies the effectiveness of the algorithm for the temperature compensation of the silicon pressure sensor,and inhibits the effect of temperature on the sensor output.Differential pressure sensor,influenced by the thermal expansion of silicone oil effect,when in high temperature environment,the sensor overload capacity will be weakened.In order to improve the overload capacity of the differential pressure sensor,this paper presents a new central diaphragm design method.The central corrugated diaphragm is used to replace the traditional flat diaphragm,which solves the problem of chips easy to exceed the overload pressure limit when in high temperature situations.The deformation theory of the corrugated diaphragm is studied,and the relationship between the theoretical pressure and the center deflection is obtained.The finite element software is used to simulate the large deflection of the corrugated diaphragm,using the equivalent temperature method to simulate the thermosetting coupling Phenomenon.The experiments of corrugated diaphragm pressure-center deflection test and flat film vs corrugated film overload test are represented in the paper.A comparative study of the results of three kinds of corrugated diaphragms(theoretical model,simulation model,actual model)is presented.The results verify the feasibility of the corrugated diaphragm design,the correctness of the mathematical model and the effectiveness of the Ansys simulation.