Evaluation Of Uncertainty In Metrology Of EMC Instruments

Uncertainty of measurement is a key part of metrology. In order to achieve themutual recognition of test reports by the calibration laboratories at home and abroad,the calibration results should be approved by the corresponding laboratories. One ofthe important requirements is that the report should include the assessment ofmeasurement uncertainty.At present, the uncertainty assessment of electromagnetic compatibility tests hasbeen explained in some articles. But for the uncertainty assessment in the metrologytracking of electromagnetic compatibility instruments, there is no detailed explanationpublished. Based on the measurement results of electromagnetic compatibilityinstruments, the uncertainty of the electromagnetic compatibility instrumentmetrology project carried out for the customers by Tianjin Electronic and InstrumentalLaboratory is assessed. The instruments assessed include electrostatic dischargeanti-interference instruments, electrical fast transient/burst instruments and surgeanti-interference instruments. The main content of this thesis is summarized asfollows.Evaluation method for the uncertainty of measurement of calibration results isdiscussed. The evaluation method for the uncertainty of measurement of calibrationresults is discussed in details by describing the establishment of the measurementmodel, analysis of the sources of uncertainty and the method for the evaluation ofstandard uncertainty. This is exactly the main evaluation method used in this thesis.This thesis is mainly focused on the analysis and evaluation of the uncertainty inthe traceability of value of the measurement instruments used in the commonelectromagnetic compatibility experiments. The sources of uncertainty that influencedthe measurement and testing result are analyzed one by one through the experiment,and the quantitative method is discussed as well. Moreover, the uncertainty of themeasurement results is analyzed and evaluated according to the method described inthis thesis for the uncertainty evaluation by applying the mathematical statisticsmethod. Finally, the uncertainties of the results in the measurement and calibration ofthe instruments with electrostatic discharge immunity, electrical fast transient burstimmunity and surge immunity are given. Other analyses and evaluations of the uncertainty of similar instrument measurements can also be performed based on themethods described in this thesis.