scholarly journals Periodic Nonlinear Error Analysis and Compensation of a Single-Excited Petal-Shaped Capacitive Encoder to Achieve High-Accuracy Measurement

Sensors ◽  
2019 ◽  
Vol 19 (10) ◽  
pp. 2412 ◽  
Author(s):  
Bo Hou ◽  
Bin Zhou ◽  
Xiang Li ◽  
Bowen Xing ◽  
Luying Yi ◽  
...  
Keyword(s):  
Measurement Range ◽  
Accuracy Measurement ◽  
Nonlinear Error ◽  
Processing Error ◽  
Analytical Simulation ◽  
Measurement Results ◽  
Periodic Error ◽  
Sensitive Structure ◽  
Harmonic Components ◽  
Nonlinear Errors

The measurement results of a single-excitation petal-shaped capacitive encoder show strong periodic characteristics for nonlinear errors. This paper presents the analysis of periodic nonlinear errors in a single-excitation petal-shaped encoder in terms of three main aspects—sensitive structure processing error, circuit demodulation error, and installation error. Analytical and simulation results confirm that the first-, second-, and fourth-periodic electrical errors are caused by the misalignment of circuit parameters, non-uniform segmentation of the processing error, and cross interference of the electric field, respectively. Further experimental investigation reveals that the mechanical periodic error is caused by installation misalignment. Based on these analytical, simulation, and experimental results, the design of the capacitive encoder was optimized and a method based on harmonic components was applied to compensate the periodic nonlinear error of the encoder. Measurement results shows that the prototype which has 180 petal-shaped numbers can achieve a reduction of periodic nonlinear errors to less than 0.02° and its accuracy can be improved to 0.0006° after compensation over the full measurement range.

State special primary acceleration measurement standard for gravimetry GET 190-2019

2020 ◽  
pp. 3-8
Author(s):  
L.F. Vitushkin ◽  
F.F. Karpeshin ◽  
E.P. Krivtsov ◽  
P.P. Krolitsky ◽  
V.V. Nalivaev ◽  
...  
Keyword(s):  
High Precision ◽  
Free Fall ◽  
Measurement Range ◽  
Measurement Standard ◽  
Acceleration Measurement ◽  
Measurement Systems ◽  
Free Fall Acceleration ◽  
Investigation Methods ◽  
Measurement Results ◽  
Upper Level

The State special primary acceleration measurement standard for gravimetry (GET 190-2019), its composition, principle of operation and basic metrological characteristics are presented. This standard is on the upper level of reference for free-fall acceleration measurements. Its accuracy and reliability were improved as a result of optimisation of the adjustment procedures for measurement systems and its integration within the upgraded systems, units and modern hardware components. A special attention was given to adjusting the corrections applied to measurement results with respect to procedural, physical and technical limitations. The used investigation methods made it possibled to confirm the measurement range of GET 190-2019 and to determine the contributions of main sources of errors and the total value of these errors. The measurement characteristics and GET 90-2019 were confirmed by the results obtained from measurements of the absolute value of the free fall acceleration at the gravimetrical site “Lomonosov-1” and by their collation with the data of different dates obtained from measurements by high-precision foreign and domestic gravimeters. Topicality of such measurements ensues from the requirements to handle the applied problems that need data on parameters of the Earth gravitational field, to be adequately faced. Geophysics and navigation are the main fields of application for high-precision measurements in this field.

scholarly journals Development of Three-Phase Permanent-Magnet Synchronous Motor Drive with Strategy to Suppress Harmonic Current

Energies ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 1583
Author(s):  
Wei-Tse Kao ◽  
Jonq-Chin Hwang ◽  
Jia-En Liu
Keyword(s):  
Permanent Magnet ◽  
Electromotive Force ◽  
Permanent Magnet Synchronous Motor ◽  
Synchronous Motor ◽  
Motor Drive ◽  
Actual Measurement ◽  
Current Harmonic ◽  
Three Phase ◽  
Measurement Results ◽  
Harmonic Components

This study aimed to develop a three-phase permanent-magnet synchronous motor drive system with improvement in current harmonics. Considering the harmonic components in the induced electromotive force of a permanent-magnet synchronous motor, the offline response of the induced electromotive force (EMF) was measured for fast Fourier analysis, the main harmonic components were obtained, and the voltage required to reduce the current harmonic components in the corresponding direct (d-axis) and quadrature (q-axis) axes was calculated. In the closed-loop control of the direct axis and quadrature axis current in the rotor reference frame, the compensation amount of the induced EMF with harmonic components was added. Compared with the online adjustment of current harmonic injection, this simplifies the control strategy. The drive system used a 32-bit digital signal processor (DSP) TMS320F28069 as the control core, the control strategies were implemented in software, and a resolver with a resolver-to-digital converter (RDC) was used for the feedback of angular position and speed. The actual measurement results of the current harmonic improvement control show that the total harmonic distortion of the three-phase current was reduced from 5.30% to 2.31%, and the electromagnetic torque ripple was reduced from 15.28% to 5.98%. The actual measurement results verify the feasibility of this method.

scholarly journals Establishment of torque realisation up to 5 kN·m with a new design of the torque standard machine

ACTA IMEKO ◽  
2019 ◽  
Vol 8 (3) ◽  
pp. 30
Author(s):  
Nittaya Arksonnarong ◽  
Nattapon Saenkhum ◽  
Pramann Chantaraksa ◽  
Tassanai Sanponpute
Keyword(s):  
Measurement Range ◽  
Uncertainty Evaluation ◽  
Torque Measurement ◽  
Calibration And Measurement Capabilities ◽  
Measurement Results ◽  
Bearing Structure ◽  
Measurement Capabilities

<p class="Abstract">A Torque Standard Machine (TSM) with a rated capacity of 5 kN·m was designed and constructed by the Torque Laboratory, National Institute of Metrology (Thailand), NIMT. The machine had initially used a flexure bearing as a fulcrum. It had been developed based on the research of a 10 N·m suspended fulcrum TSM. However, the bearing structure was changed to a combination of eight elastic hinges in order to withstand larger cross-forces for providing greater strength and providing a shorter stabilising time, consuming the lever arm’s swing. With a three-column weightlifting system, the machine provides five measuring ranges ranging from 100 N·m to 5,000 N·m in the same set of stacked weights.</p><p class="Abstract">The measurement results showed the sensitivity of the fulcrum within ± 0.005 N·m from 10 % to 100 % of the measurement range. The sensitivity of the fulcrum is one of the main sources of the uncertainty evaluation of the torque measurement. The Calibration and Measurement Capabilities (CMCs) of the torque measurement were 0.01 % (<em>k=2</em>) in the measurement range from 500 N·m to 5,000 N·m. To confirm the capability of the measurement, an informal comparison with Physikalisch-Technische Bundesanstalt (PTB) was conducted. The results were satisfactory, with the |<em>E</em><sub>n</sub>| less than 1.</p>

scholarly journals Експериментальне визначення стану текстильних матеріалів десантної парашутної системи Д-5 серії 2 після тривалого зберігання. Повідомлення 2. Статистичні характеристики результатів вимірювання показників строп основного парашуту

2021 ◽  
pp. 4-11
Author(s):  
Олександр Олександрович Корольов ◽  
Ігор Михайлович Сила ◽  
Вадим Васильович Гейко ◽  
Ольга Іллівна Сиза
Keyword(s):  
Relative Error ◽  
Measurement Range ◽  
External Factors ◽  
Accuracy Class ◽  
Elongation At Break ◽  
Long Term Storage ◽  
Measurement Results ◽  
Analysis Package ◽  
Current Article ◽  
Internal And External Factors

The subject of the article is the analysis of the array of experimental data of loading and elongation at break of the slings of the main parachute landing parachute systems D-5 series 2 1973 and 1974 years of manufacture after long-term storage with zero (inexhaustible) resource. The current article attempts to determine the ratio of external factors related to the natural factors of aging of polymers, and internal, due to errors in the measurement process, based on statistical analysis of measurement results. Objective: to determine the degree of influence of internal and external factors on the process and result of measuring indicators. The following methods and equipment were used. An improved method of spot sampling of the samples under study of landing parachute systems D-5 series 2 for laboratory studies to determine the load at break and elongation at break of the slings of the main parachute. Measurements were performed on a machine of bursting brand ИР 5047-50M2C, accuracy class - 0.5 for the measurement range from 0.5 kN to 5 kN. The volume of the party was 25 parachute systems, only 250 elementary tests. The array of empirical data was processed by mathematical and statistical methods of the software package Descriptive statistics on the add-on of MS EXCEL Analysis Package. The following results were obtained. The relative error of the results of load measurement when breaking the slings of the domes of parachutes of 1973 production was ± 5.0%, for parachutes of 1974 production - ± 3.8%. The relative error of the results of measuring the elongation at the break of the slings of the domes of parachutes of 1973 manufacture was ± 2.9%, for parachutes of 1974 manufacture ± 3.3%. Given that the measuring instrument has an error of ± 0.29% in the passport, which can be considered systematic, the overall level of uncertainty is acceptable for conventional measurements in engineering. Conclusions. The main factors of accidental errors in the process of measuring the load at break and elongation at break of the slings of the main parachute are external factors due to the state of the cord structure and changes in the internal structure of the polymer.

scholarly journals In-Situ Wireless Pressure Measurement Using Zero-Power Packaged Microwave Sensors

Sensors ◽  
2019 ◽  
Vol 19 (6) ◽  
pp. 1263 ◽  
Author(s):  
Julien Philippe ◽  
Maria De Paolis ◽  
Dominique Henry ◽  
Alexandre Rumeau ◽  
Antony Coustou ◽  
...  
Keyword(s):  
Dynamic Range ◽  
Pressure Sensors ◽  
Measurement Range ◽  
Full Scale ◽  
Remote Measurement ◽  
Reverberant Environments ◽  
Indoor Wireless ◽  
Measurement Results ◽  
Radar Imagery ◽  
First Time

This paper reports the indoor wireless measurement of pressure from zero-power (or passive) microwave (24 GHz) sensors. The sensors are packaged and allow the remote measurement of overpressure up to 2.1 bars. Their design, fabrication process and packaging are detailed. From the measurement of sensor scattering parameters, the outstanding sensitivity of 995 MHz/bar between 0.8 and 2.1 bars was achieved with the full-scale measurement range of 1.33 GHz. Moreover, the 3D radar imagery technique was applied for the remote interrogation of these sensors in electromagnetic reverberant environments. The full-scale dynamic range of 4.9 dB and the sensitivity of 4.9 dB/bar between 0.7 and 1.7 bars were achieved with radar detection in a highly reflective environment. These measurement results demonstrate for the first time the ability of the radar imagery technique to interrogate fully passive pressure sensors in electromagnetic reverberant environments.

Development and Evaluation of a High Resolution Turbine Pyrometer System

2001 ◽  
Author(s):  
Torsten Eggert ◽  
Bjoern Schenk ◽  
Helmut Pucher
Keyword(s):  
High Resolution ◽  
Gas Turbine ◽  
Gas Turbines ◽  
Turbine Rotor ◽  
Measurement Range ◽  
Test Facility ◽  
Radial Turbine ◽  
Measurement Results ◽  
Technical University ◽  
Industrial Gas Turbine

Optical pyrometers provide many advantages over intrusive measuring techniques in determining the spatial and time varying temperature distribution of fast rotating components in gas turbines. This paper describes the development and evaluation of a versatile high resolution pyrometer system and its application to radial turbine rotor temperature mapping as has been done in a R&D project at the Technical University Berlin under funding from Siemens Power Generation (KWU). The development goal was a pyrometer system with a temporal resolution of 1μs, a minimum field of view of 1 mm, and a measurement range from 600 to 1500°C. A prototype of the pyrometer system has been built and tested at the small gas turbine test facility of the Technical University Berlin. The system yielded excellent results with respect to measurement uncertainty, resolution, and reliability. Finally, measurement results obtained with the new system on a radial turbine rotor and on a heavy duty industrial gas turbine are compared with measurements conducted with a commercially available turbine pyrometer system.

scholarly journals Measurement of the Casimir Force between 0.2 and 8 μm: Experimental Procedures and Comparison with Theory

Universe ◽  
2021 ◽  
Vol 7 (4) ◽  
pp. 93
Author(s):  
Giuseppe Bimonte ◽  
Benjamin Spreng ◽  
Paulo A. Maia Neto ◽  
Gert-Ludwig Ingold ◽  
Galina L. Klimchitskaya ◽  
...  
Keyword(s):  
Quantum Electrodynamics ◽  
Casimir Force ◽  
Measurement Range ◽  
Optical Data ◽  
Kelvin Probe ◽  
Kelvin Probe Microscopy ◽  
Measurement Results ◽  
Force Signal ◽  
Measured Force ◽  
Silicon Trenches

We present results on the determination of the differential Casimir force between an Au-coated sapphire sphere and the top and bottom of Au-coated deep silicon trenches performed by means of the micromechanical torsional oscillator in the range of separations from 0.2 to 8 μm. The random and systematic errors in the measured force signal are determined at the 95% confidence level and combined into the total experimental error. The role of surface roughness and edge effects is investigated and shown to be negligibly small. The distribution of patch potentials is characterized by Kelvin probe microscopy, yielding an estimate of the typical size of patches, the respective r.m.s. voltage and their impact on the measured force. A comparison between the experimental results and theory is performed with no fitting parameters. For this purpose, the Casimir force in the sphere-plate geometry is computed independently on the basis of first principles of quantum electrodynamics using the scattering theory and the gradient expansion. In doing so, the frequency-dependent dielectric permittivity of Au is found from the optical data extrapolated to zero frequency by means of the plasma and Drude models. It is shown that the measurement results exclude the Drude model extrapolation over the region of separations from 0.2 to 4.8 μm, whereas the alternative extrapolation by means of the plasma model is experimentally consistent over the entire measurement range. A discussion of the obtained results is provided.

Extensional Rheology of LDPE from Melt Spinning Technique

2011 ◽  
Vol 675-677 ◽  
pp. 499-502
Author(s):  
Lei Zhong ◽  
Ji Zhao Liang
Keyword(s):  
Melt Spinning ◽  
Measurement Range ◽  
Scaling Factor ◽  
Low Density Polyethylene ◽  
Reference Curve ◽  
Extensional Rheology ◽  
Factor B ◽  
Measurement Results ◽  
Curve Extension ◽  
Melt Spinning Technique

The extensional rheology of low density polyethylene (LDPE) is studied bymelt spinning technique. Melt spinning mastercurves for LDPE are plotted for the measurement results of various temperatures and extrusion velocities. Linear relations between scaling factor b and T, Logb and Logv0 have been found. The analysis indicates that b can be regarded as a useful index of combination effects on the pre-orientation before extension, and on the unwrapping and orientation of macromolecular chains during extension. By using the values of b and the data from reference curve, extension viscosity curves of any setting temperature and extrusion velocity can be calculated, which will effectively enlarge the measurement range of melt spinning technique.

Development and Evaluation of a High-Resolution Turbine Pyrometer System

2002 ◽  
Vol 124 (3) ◽  
pp. 439-444 ◽  
Author(s):  
Torsten Eggert ◽  
Bjoern Schenk ◽  
Helmut Pucher
Keyword(s):  
High Resolution ◽  
Gas Turbine ◽  
Gas Turbines ◽  
Turbine Rotor ◽  
Measurement Range ◽  
Test Facility ◽  
Radial Turbine ◽  
Measurement Results ◽  
Technical University ◽  
Industrial Gas Turbine

Optical pyrometers provide many advantages over intrusive measuring techniques in determining the spatial and time varying temperature distribution of fast rotating components in gas turbines. This paper describes the development and evaluation of a versatile high-resolution pyrometer system and its application to radial turbine rotor temperature mapping as has been done in a R&D project at the Technical University Berlin under funding from Siemens Power Generation (KWU). The development goal was a pyrometer system with a temporal resolution of 1 μs, a minimum field of view of 1 mm, and a measurement range from 600 to 1500°C. A prototype of the pyrometer system has been built and tested at the small gas turbine test facility of the Technical University Berlin. The system yielded excellent results with respect to measurement uncertainty, resolution, and reliability. Finally, measurement results obtained with the new system on a radial turbine rotor and on a heavy duty industrial gas turbine are compared with measurements conducted with a commercially available turbine pyrometer system.

scholarly journals Analysis, Design, and Actual Fabrication of a Hybrid Microstrip-SIW Bandpass Filter Based on Cascaded Hardware Integration at X-Band

2021 ◽  
Vol 27 (1) ◽  
pp. 23-28
Author(s):  
Kemal Guvenli ◽  
Sibel Yenikaya ◽  
Mustafa Secmen
Keyword(s):  
Bandpass Filter ◽  
Center Frequency ◽  
Frequency Change ◽  
Substrate Integrated Waveguide ◽  
Lowpass Filter ◽  
Analytical Simulation ◽  
X Band ◽  
Measurement Results ◽  
Highpass Filter ◽  
In Series

In this paper, the Microstrip-Substrate Integrated Waveguide (M-SIW) bandpass filter is designed, simulated, and fabricated based on the theoretical analysis. The Substrate Integrated Waveguide (SIW) highpass filter and the microstrip lowpass filter are combined in a hybrid design to achieve the M-SIW bandpass filter in the X-band. This design is more comprehensible and easier to achieve a bandpass filter at a desired frequency. The SIW highpass filter and the microstrip lowpass filter are connected in series to achieve the bandpass filter. To the measured results of the fabricated M-SIW bandpass filter, the center frequency is 10.20 GHz and the bandwidth is 2.40 GHz. When the analytical and measurement results are compared, the frequency change in the cut-off frequency is 6.02 % and the frequency change in the bandwidth is 8.74 %. It is generally seen that analytical, simulation, and measurement results are compatible with each other. The M-SIW bandpass filter can be broadly used in radar, Worldwide Interoperability for Microwave Access (WiMAX), and satellite technologies. The filters are simulated in Computer Simulation Technology (CST) Studio Suite.

Sign in / Sign up

Export Citation Format

Share Document