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HIGH-PRECISION, RAPID READOUT OF CRYOGENIC temperature sensorS IN THE SPACE-SHUTTLE ENVIRONMENT

IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT 1990年第1期39卷 279-284页

作者： WOODHOUSE, CE NASA GODDARD SPACE FLIGHT CTRGREENBELTMD 20771

A compact and rugged system designed to perform four-wire determination of the resistance of germanium resistance thermometers (GRT) near 1 K to one part in 65000 in 1 s using 20-nW excitation is described. Constraints unique to cryogenic aerospace systems are addressed. A microcomputer-controlled, hybrid analog/digital design is presented. Test results are presented, and future developments are discussed.

关键词： Space shuttle resistance thermometers aerospace systems temperature sensor device component cryogenic temperature sensors readout four-wire Technological forecasting

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Are complex black-box models for Permanent Downhole Gauge pressure estimation necessary?

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JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING 2019年 173卷 715-732页

作者： Huffner, Leonardo Nardi Trierweiler, Jorge Otavio Farenzena, Marcelo Fed Univ Rio Grande Sul UFRGS Grp Intensificat Modeling Simulat Control & Optim Chem Engn Dept R Engn Luiz Englert S-NCampus Cent BR-90040040 Porto Alegre RS Brazil

The Permanent Downhole Gauge (PDG) is a pressure and temperature sensor located subsea near the perforation point in the offshore oil production system. This sensor is very useful in operation problems detection (fouling, valves, plugging, etc.), multiphasic flow analysis, production tests adjustment, control strategy and model identification. Given its location under hazardous conditions, it may come to failure or imprecisions in measurement. The high costs related to the maintenance make it infeasible to perform. To overcome this issue, a methodology based on digital signal processing (DSP) is proposed in order to design a low pass digital filter aiming the PDG pressure reconstruction. The proposed methodology requires no plant model, low computational cost and only the Christmas-Tree pressure measurement. The proposed methodology is compared with two commonly employed black-box methodologies: Neural Network and Transfer Function Estimation. The results show the success of the designed filter and the advantages over the black-box approaches. The estimation of the PDG pressure from three operating wells using real process data was performed.

关键词： Subsea plant models model identification Batch data processing Production systems BLACK-BOX TRANSFER FUNCTIONS temperature sensor device component PHGDH gene

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Fabrication and evaluation of a drag-force type dual flow sensor with an embedded temperature sensor

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MICROSYSTEM TECHNOLOGIES-MICRO-AND NANOSYSTEMS-INFORMATION STORAGE AND PROCESSING SYSTEMS 2018年第4期24卷 1975-1985页

作者： Choi, Dae Keun Lim, Yong U. Lee, Sang Hoon Seoul Natl Univ Sci & Technol Grad Sch NID Fus Technol Gongreung 2 Dong Seoul 139743 South Korea Seoul Natl Univ Sci & Technol Dept Automot Engn Gongreung 2 Dong Seoul 139743 South Korea Korea Inst Ind Technol KITECH 143 Hanggaul Ro Ansan 15588 Gyeonggi Do South Korea

We designed and fabricated a drag-force type dual flow sensor with an embedded temperature sensor. For the wide range detection, two devices in varying length (300 and 700 mu m) were used. The corrugated structure was applied for high sensitivity, and the paddle structure was also adopted to enhance the air drag force. The sensor measured the wide range air flow rate from 0.5 up to 8 m/s with a step width at 0.5 m/s. The 700 mu m-long sensor showed about 1.5 times larger sensitivity than the 300 mu m-long sensor in the low air flow. The results showed that the 700 mu m-long device is suitable for low velocity measurements. However, the 300 mu m-long sensor showed better sensitivity in the higher air flow;thus, the 300 mu m-long sensor is suitable for high velocity measurements. In addition, the embedded temperature sensor measured the basic temperature, and the measured sensitivity was compensated by temperature which could affect the flow sensor. It also showed a linear shape in resistance change related with temperature.

关键词： embedding fabrication Speed measurement step size Greek characters temperature sensor device component FLOW sensor sensors air drag

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A temperature sensor with single resistor set-point programming

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IEEE JOURNAL OF SOLID-STATE CIRCUITS 1996年第12期31卷 1908-1915页

作者： Brokaw, AP Analog Devices Inc.orporated Wilmington MA USA

An integrated circuit set point temperature controller has an open collector output which switches low at a temperature determined bg an external resistor, The programming resistor may be determined from a universal formula relating resistance to desired trip temperature. The circuit is laser trimmed at a single temperature in manufacture to conform with the formula to better than 1 degrees C over a range between -4 degrees C and 150 degrees C. The circuit is low cost and includes temperature hysteresis, for well defined switching, and an optional output pull-up resistor.

关键词： thermostats formula Resistor device component temperature temperature sensor device component Programming Laser Set of points

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LHC Thermometry: Laboratory Precision on an Industrial Scale in a Hostile Environment: Tutorial 52 Part 52 in a series of tutorials on instrumentation and measurement

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IEEE INSTRUMENTATION & MEASUREMENT MAGAZINE 2014年第1期17卷 57-+页

作者： Casas, Juan CERN CH-1211 Geneva 23 Switzerland

The measurement of cryogenic temperatures is essential for operating large-scale cryogenic installations and in experimental set-ups used for understanding low temperature physics phenomena. Recommendations on how to select and operate temperature sensors can be found in [1]-[2]. This paper presents how the CERN\'s Large Hadron Collider (LHC) [3] requirements for measurement of cryogenic temperatures were met [4]-[9]. The main challenge was a temperature uncertainty of ±0.01 K in the range 1.8 K to 2.2 K that should take into account the background radiation field provoked by the LHC circulating proton beams, the sheer quantity of the measuring channels, and an operational lifetime of at least 20 years. The LHC superconducting magnets\' temperature measurements are used in feedback closed control loops to adjust the cooling power. The measurement uncertainty has thus a direct impact on the width of the temperature control range that shall be as wide as possible to increase the availability of appropriate operation conditions for permitting the circulation of particle beams around the LHC accelerator.

关键词： measurement uncertainty cryogenic temperature Operating life hostile environment measuring instruments Large Hadron Collider measurement channel temperature sensor device component Thermometry RADIATION FIELD Tutorials

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IMPROVED OCXOS OVEN USING ACTIVE THERMAL INSULATION

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IEEE TRANSACTIONS ON ULTRASONICS FERROELECTRICS AND FREQUENCY CONTROL 1994年第2期41卷 269-274页

作者： BRENDEL, R MARIANNEAU, G DJIAN, F ROBERT, E Centre National de la Recherche Scientifique Laboratoire de Physique et Metrologie des Oscillateurs Besancon France

This paper shows how it is possible to improve the performance of thermal enclosures by using a compensating system the principle of which has been described by F. Walls a few years ago (41st AFCS, 1987). It is shown that because of the thermal network between the outside temperature, the temperature sensor and the device to be regulated, the latter may undergo residual temperature variations which reduce the overall thermal efficiency of the oven. This paper shows how thermal transfer functions can be measured by using an experimental setup in which the node temperatures are measured by thermal sensors. By identifying the thermal response of the nodes with the theoretical transfer function under external temperature or heater excitation, the components of the equivalent R-C network can be determined. By knowing these thermal transfer functions, it is then possible to make use of a compensating system which can eliminate the parasitic static as well as dynamic thermal effects. Validating measurements and experimental results are presented which show the strong improvement achieved by this compensating system with respect to the conventional approach.

关键词： thermal transfer Ganglia THERMAL sensor TRANSFER FUNCTIONS Ovens Thermal insulation temperature sensor device component compensation system

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A probabilistic model for information and sensor validation

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COMPUTER JOURNAL 2006年第1期49卷 113-126页

作者： Ibargüengoytia, PH Vadera, S Sucar, LE Univ Salford Salford M5 4WT Lancs England ITESM Cuernavaca Morelos Mexico

This paper develops a new theory and model for information and sensor validation. The model represents relationships between variables using Bayesian networks and utilizes probabilistic propagation to estimate the expected values of variables. If the estimated value of a variable differs from the actual value, an apparent fault is detected. The fault is only apparent since it may be that the estimated value is itself based on faulty data. The theory extends our understanding of when it is possible to isolate real faults from potential faults and supports the development of an algorithm that is capable of isolating real faults without deferring the problem to the use of expert provided domain-specific rules. To enable practical adoption for real-time processes, an any time version of the algorithm is developed, that, unlike most other algorithms, is capable of returning improving assessments of the validity of the sensors as it accumulates more evidence with time. The developed model is tested by applying it to the validation of temperature sensors during the start-up phase of a gas turbine when conditions are not stable;a problem that is known to be challenging. The paper concludes with a discussion of the practical applicability and scalability of the model.

关键词： Scalability real-time process algorithms sensors Probabilistic Model temperature sensor device component Bayesian networks

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Design and development of a smart wireless system for passive temperature sensors

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SMART MATERIALS & STRUCTURES 2000年第4期9卷 379-388页

作者： Varadan, VK Teo, PT Jose, KA Varadan, VV Penn State Univ Ctr Engn Elect & Acoust Mat University Pk PA 16802 USA

The design and development of a smart wireless system for remote reading of a passive surface acoustic wave (SAW) sensor is presented in this paper. The SAW sensor is a lithium niobate wafer with an inter-digital transducer (IDT) with reflectors, which is inductively coupled to a microstrip meander antenna (ICMA). The reading system is a special FM radar, which transmits and receives FM electromagnetic signals. The transmitted FM signal is picked up by the ICMA which subsequently, converts into a SAW in the LiNbO3 wafer through the IDTs. These SAWs are reflected back to the IDTs by the reflectors, converted back to an electromagnetic wave and returned to the FM radar by the ICMA. The acoustic velocity varies as a function of the propagation characteristics of the SAW in the substrate and results in varying time delay of the echoes, which is detected by the system. The resolution and accuracy of such a system are investigated theoretically and experimentally. The operating principle is evaluated for a remote temperature measurement system. The salient feature of this system is that no power source is required at the sensor and thus is applicable for remote temperature sensing of propellant in barrel-launched adaptive munitions (BLAM), tank rounds and other munitions and missiles. This is also suitable for other remote reading SAW sensors such as indentity tags, wireless pressure sensors, wireless gas sensors, strain sensors, hospital sterilizer sensors, etc.

关键词： interdigital transducers temperature sensing Electric Power Source Echoes frequency modulated radars surface acoustic wave sensors temperature sensor device component sensors reflectors Surface acoustic waves electromagnetic waves CARRIER SYSTEM

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Thin-film AC-DC converter with thermoresistive sensing (vol 46, pg 382, 1997)

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IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT 1997年第5期46卷 1212-1212页

作者： Katzmann, FL Montclair Sci Instruments Cedar Grove NJ 07009 USA

New thermal converter designs for accurate alternating ac-dc transfer are realized in thin-film design of heaters and aluminum thermoresistive temperature sensors deposited on a thin dielectric membrane. Low mass heater/sensor configuration assures minimal thermal inertia, so as to reduce settling time and speed up ac-dc transfer. An optional silicon obelisk serves as a thermal integrator to avoid low-frequency ac-dc transfer differences. This design is enhanced by isothermal operation and transfers only slightly more slowly than the standard configuration without the obelisk. The thermoresistive design has an Improved signal-to-noise ratio (SNR) compared to thermal converters using thermocouples and lowers the manufacturing cost of thermal converters.

关键词： Heaters thermal converter DC conversion Thermocouple Converters setting time Manufacturing costs DC converter signal to noise ratios temperature sensor device component Thermal thermal inertia

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High temperature diode sensors based on InGaN/AlGaN structures

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JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B 2018年第2期36卷 022905-1-022905-5页

作者： Krasnov, Vasily A. Shutov, Stanislav V. Yerochin, Sergey Y. Demenskiy, Aleksey N. Natl Acad Sci Ukraine V Lashkaryov Inst Semicond Phys Lab Mat Optoelect N23 76-78 Zavodskaya St UA-73008 Kherson Ukraine

The authors have established the factors defining the maximum temperature limit of operating as well as the thermal sensitivity of the diode temperature sensors based on double heterostructures InGaN/AlGaN in a condition when tunnel current flow prevails. The authors have obtained analytic dependencies for the maximum temperature and sensitivity and have analyzed a connection of these characteristics with the parameters of the semiconductor material and the diode structure. In particular, it was shown that the sensitivity did not depend on the diode sensor operation current and, in the case of double heterostructure, its value was proportional to the energy gap difference of the heterojunction. Relying on the experimental data, the authors state that to design a diode temperature sensor possessing maximum values of operation temperature and thermal sensitivity at minimal operation current, it is necessary to utilize double heterostructures based on wide bandgap semiconductors. Base and emitter layers of the structure should be heavily doped. The optimal value of the energy gap difference between active and confining layers of about 0.2-0.3 eV should be provided. In addition, in the double heterostructure chosen, the tunnel transport of the charge carriers with smaller effective mass should dominate. Published by the AVS.

关键词： temperature InGaN/AlGaN structures Heat intolerance effective mass Best value temperature temperature sensor device component diodes Writers energy gap operating temperature AVS Charge carriers

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