Research On The Design And Implementation Technology Of High Precision Resistance Calibrator

As we all know,digital multimeter and other measuring instruments are widely used in the field of engineering research.In the use of measuring instruments,we need to ensure its measurement accuracy and stability.Therefore,a calibration instrument with a sufficiently high accuracy is required to satisfy the measurement accuracy requirements.However,the domestic research of the calibrator is not deep enough,and the accuracy of calibration equipment cannot meet the higher calibration requirements.Resistor calibration as a major function of calibrator,which can calibrate the ohm file of measure equipment,so the research of resistance calibrator design and implementation technology is of great significance.This paper studies the design and implementation technology of the resistance calibrator,and designs the resistance calibrator.Its accuracy can up to three hundred thousandths,which can meet the six and a half digital multimeter ohm file calibration requirements.In order to ensure the stability and accuracy of the output resistance of the resistance calibrator,the design methods to improve the stability and test accuracy of the instrument are studied,and the system error analysis and error compensation scheme are designed.And the system error analysis and error compensation scheme are designed.According to the results of the overall program design results,the design scheme is implemented on the hardware.The control logic is designed and verification platform is built.Then we test the resistance calibrator and analyze its performance indicators.The specific research contents are as follows:Firstly,the function and performance index of the high precision resistance calibrator are analyzed in detail,and the overall scheme of the system is designed according to the requirement of the index,including the system hardware circuit design and the software overall scheme design.The simulation software is used to analyze the feasibility of the circuit scheme.Secondly,the design methods to improve the stability and test accuracy of the instrument are studied,and the system error analysis and error compensation scheme are designed.High stability signal conditioning method and high precision data conversion technology were studied,and the precision signal conditioning circuit includes a signal input circuit and a signal output circuit.Then the error analysis and error compensation scheme design of the whole system is designed to improve the system accuracy.The possible noise in the system is analyzed and the relevant anti-jamming measures are put forward.Again,design the hardware circuit according to the overall design scheme,including the overall hardware circuit design,signal input circuit,digital-analog converter circuit and so on.The software design includes FPGA internal logic design and automatic test software design,which can control system to achieve range switching,data conversion and automatic testing and other functions.Finally,build a resistance calibrator verification platform and design the test program.Perform a comprehensive and detailed performance test of the designed resistance calibrator.According to the test results for analysis,put forward the design of the shortcomings and prospects.