New approaches for identification of systematic measurement errors in linear steady state and dynamic processes

Abstract Autocollimators are versatile devices for angle metrology used in a wide range of applications in engineering and manufacturing. A modern electronic autocollimator generally features two measuring axes and can thus fully determine the surface normal of an optical surface relative to it in space. Until recently, however, the calibration capabilities of the national metrology institutes were limited to plane angles. Although it was possible to calibrate both measuring axes independently of each other, it was not feasible to determine their crosstalk if angular deflections were present in both axes simultaneously. To expand autocollimator calibrations from plane angles to spatial angles, PTB and VTT MIKES have created dedicated calibration devices which are based on different measurement principles and accomplish the task of measurand traceability in different ways. Comparing calibrations of a transfer standard makes it possible to detect systematic measurement errors of the two devices and to evaluate the validity of their uncertainty budgets. The importance of measurand traceability via calibration for a broad spectrum of autocollimator applications is one of the motivating factors behind the creation of both devices and for this comparison of the calibration capabilities of the two national metrology institutes. The latter is the focus of the work presented here.

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A PMU-based Technique for the Simultaneous Estimation of Systematic Measurement Errors, Line Parameters and Tap Changer Ratio

10.1109/amps50177.2021.9586026 ◽

2021 ◽

Author(s):

Paolo Attilio Pegoraro ◽

Carlo Sitzia ◽

Antonio Vincenzo Solinas ◽

Sara Sulis

Keyword(s):

Measurement Errors ◽

Systematic Measurement ◽

Simultaneous Estimation ◽

Tap Changer

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Identification of Overhead-Line Parameters from PMU Data with Compensation of Systematic Measurement Errors

2018 International Conference on Industrial Engineering, Applications and Manufacturing (ICIEAM) ◽

10.1109/icieam.2018.8728793 ◽

2018 ◽

Cited By ~ 2

Author(s):

Yu.G. Kononov ◽

O.S Rybasova ◽

K.A. Sidirov

Keyword(s):

Measurement Errors ◽

Systematic Measurement ◽

Overhead Line

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Compensation of Systematic Measurement Errors in a PMU-Based Monitoring System for Electric Distribution Grids

IEEE Transactions on Instrumentation and Measurement ◽

10.1109/tim.2019.2908703 ◽

2019 ◽

Vol 68 (10) ◽

pp. 3871-3882 ◽

Cited By ~ 6

Author(s):

Paolo Attilio Pegoraro ◽

Kyle Brady ◽

Paolo Castello ◽

Carlo Muscas ◽

Alexandra von Meier

Keyword(s):

Monitoring System ◽

Measurement Errors ◽

Systematic Measurement ◽

Electric Distribution ◽

Distribution Grids

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Inverse Determination of Temperature-Dependent Thermal Conductivity Using Steady Surface Data on Arbitrary Objects

Journal of Heat Transfer ◽

10.1115/1.1287726 ◽

2000 ◽

Vol 122 (3) ◽

pp. 450-459 ◽

Cited By ~ 13

Author(s):

T. J. Martin ◽

G. S. Dulikravich

Keyword(s):

Thermal Conductivity ◽

Heat Flux ◽

Steady State ◽

Measurement Errors ◽

Three Dimensional ◽

Convection Heat Transfer ◽

Computational Procedure ◽

Heat Fluxes ◽

Computational Method ◽

Transfer Coefficients

An inverse computational method has been developed for the nonintrusive and nondestructive evaluation of the temperature-dependence of thermal conductivity. The methodology is based on an inverse computational procedure that can be used in conjunction with an experiment. Given steady-state heat flux measurements or convection heat transfer coefficients on the surface of the specimen, in addition to a finite number of steady-state surface temperature measurements, the algorithm can predict the variation of thermal conductivity over the entire range of measured temperatures. Thus, this method requires only one temperature probe and one heat flux probe. The thermal conductivity dependence on temperature (k-T curve) can be completely arbitrary, although a priori knowledge of the general form of the k-T curve substantially improves the accuracy of the algorithm. The influence of errors of measured surface temperatures and heat fluxes on the predicted thermal conductivity has been evaluated. It was found that measurement errors of temperature up to five percent standard deviation were not magnified by this inverse procedure, while the effect of errors in measured heat fluxes were even lower. The method is applicable to two-dimensional and three-dimensional solids of arbitrary shape and size. [S0022-1481(00)01703-5]

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