WO1994011763A1 - Base de temps stabilisee par rapport aux temperatures elevees - Google Patents

Base de temps stabilisee par rapport aux temperatures elevees Download PDF

Info

Publication number
WO1994011763A1
WO1994011763A1 PCT/US1993/010932 US9310932W WO9411763A1 WO 1994011763 A1 WO1994011763 A1 WO 1994011763A1 US 9310932 W US9310932 W US 9310932W WO 9411763 A1 WO9411763 A1 WO 9411763A1
Authority
WO
WIPO (PCT)
Prior art keywords
time base
isolation enclosure
predetermined temperature
temperature
stabilized time
Prior art date
Application number
PCT/US1993/010932
Other languages
English (en)
Inventor
Kenneth L. Jones
Original Assignee
Western Atlas International, Inc.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Western Atlas International, Inc. filed Critical Western Atlas International, Inc.
Priority to EP94902231A priority Critical patent/EP0635137A4/fr
Publication of WO1994011763A1 publication Critical patent/WO1994011763A1/fr
Priority to NO942573A priority patent/NO942573D0/no

Links

Classifications

    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03L—AUTOMATIC CONTROL, STARTING, SYNCHRONISATION OR STABILISATION OF GENERATORS OF ELECTRONIC OSCILLATIONS OR PULSES
    • H03L1/00—Stabilisation of generator output against variations of physical values, e.g. power supply
    • H03L1/02—Stabilisation of generator output against variations of physical values, e.g. power supply against variations of temperature only
    • H03L1/04—Constructional details for maintaining temperature constant
    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05D—SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
    • G05D23/00—Control of temperature
    • G05D23/19—Control of temperature characterised by the use of electric means
    • G05D23/1906—Control of temperature characterised by the use of electric means using an analogue comparing device
    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05D—SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
    • G05D23/00—Control of temperature
    • G05D23/19—Control of temperature characterised by the use of electric means
    • G05D23/20—Control of temperature characterised by the use of electric means with sensing elements having variation of electric or magnetic properties with change of temperature

Definitions

  • This invention relates generally to the provision of a stabilized timing reference such as is provided by solid state timers, crystal oscillators and the like. More particularly, the present invention is directed to the provision of a stable timing reference in downhole well logging instruments for provision of a stabilized time reference signal for effective instrument operation over a large spectrum of operating temperatures while eliminating typical loss of accuracy due to temperature variations, line loss and skew caused by the resistance and capacitance of the lengthy wireline required for a well logging operation.
  • Timing devices i.e., solid state timers, such as crystal oscillators and the like
  • Solid state timers such as crystal oscillators and the like
  • changing the temperature degrades their stability. It is desirable, therefore, to provide means for maintaining the timing device within a designated, quite narrow temperature range that permits the timing device to operate at maximum efficiency and accuracy.
  • the ambient temperature of the downhole well environment varies with depth and well location. Thus, during a downhole well logging operation, the logging instrument will typically encounter a wide variety of ambient temperatures depending upon its location in the well bore. Some of these temperatures may be above or below the stable operating temperature range of crystal oscillators and other timing devices.
  • timing device or devices are maintained within a narrow temperature range which is an elevated temperature range above that of the maximum ambient temperature of use while operating in a well logging environment where the ambient temperature varies with depth and well location.
  • a system for maintaining a high temperature stabilized time base which comprises a low thermal-conduction oven or isolation enclosure of sufficient dimension to accommodate the time base and control circuitry.
  • the low thermal-conduction oven is provided with a heating and/or cooling element capable of maintaining a required mass within a predetermined temperature range.
  • the heating/cooling oven is provided with a control circuit having a temperature sensor that is designed to monitor internal oven temperature and regulate the supply of electrical power to the heater or to the cooling element as the case may be.
  • a timing device is provided which is specifically designed to have frequency stability at a predetermined elevated temperature range.
  • the circuit components of the time base is maintained at the predetermined elevated temperature regardless of well temperature to thus ensure the stability of the time base in the downhole environment. Where excessively hot well conditions are encountered, or if the time base circuitry is stable only at a temperature lower than the ambient temperature of the well the protective enclosure for the circuitry may also be provided with controlled cooling to maintain the temperature of the time base within the range of its stability.
  • Fig. 1 is a block diagram schematic illustration of a high temperature stabilized time base for well logging instruments which is constructed in accordance with the features of the present invention.
  • Fig. 2 is a sectional view of the heat maintaining oven of the stabilized time base of Fig. 1, showing the temperature generation and control devices together with the time base signal generating device being located within the temperature control oven.
  • Fig. 3 is a block diagram electronic schematic representing an alternative embodiment of the present invention, for selectively heating or cooling the electronic circuitry.
  • a stabilized time base system shown generally at 10 is provided for incorporation within a downhole well logging instrument, a portion of which is shown at 12.
  • the stabilized time base includes a low thermal-conductive oven or isolation enclosure 14 is located within the logging instrument 12 and functions as a thermal isolator which is used to contain heat for the purpose of maintaining the efficiency of electronic circuitry disposed within an internal compartment 16 thereof.
  • the low thermal- conductive oven also functions to isolate the heat contained therein to lessen the effects of thermal transience to which the instrument 12 might be subjected.
  • the oven structure is also employed as the means of mounting the hardware to a backbone.
  • the cavity or compartment 16 of the oven structure is of a dimension and design for effective support of the electronic time base and heat control circuitry.
  • the oven structure is composed of a material such as polyether ether ketone having a low thermal conductivity and having a characteristic of acceptable thermal expansion.
  • the oven structure is composed of a material that is easily machinable or molded for the complex shapes that may be required within the oven cavity 16.
  • an electrically energized heating element 18 having the capability of producing sufficient heat to maintain an internal oven temperature at the lowest required ambient temperature that is expected to be encountered within the well bore.
  • the electronic heating element has the capability of being energized from an electric power circuit 23 by electrical energy from a suitable source 25 such as a supply cable, onboard battery, etc.
  • a cooling element 20 which is electrically energized and controlled through a control circuit 22.
  • the cooling element is utilized where the ambient borehole temperature is above that of the oscillator's stable operating temperature, thus requiring cooling in order to maintain the oven cavity 16 within a predetermined temperature range for stability and efficiency of the timing device.
  • the cooling element may employ Peltier- Junction cooling to lower the oscillator's temperature when required to maintain its operational stability.
  • a temperature sensor 24 which provides temperature signals via conductor 26 to the control circuit 22.
  • the control circuit induces energization of the heating element 18 periodically in order to maintain the temperature of the cavity 16 and its circuit components within a narrow predetermined temperature range, being the temperature range within which the timing signal generator is stable.
  • the control circuit 22 is selectively coupled via control conductors 28 and 30 to the cooling element 20 and to the heating element 18.
  • the heating and cooling elements are selectively energized by the control circuit 22 to introduce heating or cooling into the cavity 16 to compensate for heat gain or loss and thereby maintain a predetermined typically quite narrow temperature range within the cavity.
  • a signal generator circuit 32 which may conveniently take the form of a crystal oscillator circuit having a predetermined timing frequency output signal via output conductor 34 which extends through the oven wall structure.
  • the control circuit 22 may conveniently be defined by a circuit board having appropriate electrical components for receiving the temperature signal of the sensor 24 and providing operation and control signals to the heating element 18 or cooling element 20.
  • the temperature sensor of the control circuit will typically sense temperature of the time base substrate within a range of about 1° C. The temperature is monitored and feedback signals of the temperature sensor are used to control the heater/cooler circuits, thus maintaining the desired temperature within the oven compartment.
  • the power source for the temperature sensor must also be maintained at the elevated temperature of the oven compartment to eliminate circuit temperature induced circuit drift. Temperature fluctuations outside the oven affect the heat loss of the oven.
  • the control circuitry must sense this change and compensate accordingly.
  • the crystal oscillator is a specially designed part that has integrated temperature stability at the desired elevated temperature. The specific crystal oscillator design is not a part of this invention except to the extent that it and its temperature for effective stability of operation are maintained within an appropriate typically narrow predetermined temperature range and it thus provides a stable timing reference over a large spectrum of operating temperatures ranging from 20° C to 300° C and above, which temperature ranges are common in deep petroleum wells.
  • the crystal oscillator or other frequency output generator is thus capable of providing a consistent and stable output signal which maintains its accuracy even though the apparatus is subjected to temperature variations. Since the electronic timing signal is generated at the downhole well logging instrument, it is not subjected to temperature variations, line loss and skew that might otherwise be caused by the resistance and capacitance of the lengthy wireline that is ordinarily required for well logging operations. Even though significant changes in ambient temperature are encountered by the well logging instrument during its traverse of the borehole, or its use at different borehole depths, the crystal oscillator or other frequency output device is capable of maintaining a consistent and accurate timing frequency output signal because it is not adversely influenced by ambient temperature changes.
  • the temperature within the internal cavity of the low thermal conductive oven is maintained at a narrow temperature range that is above the maximum temperature that is expected to be encountered by the logging instrument at any depth in the well bore.
  • the temperature control system will be also provided with a cooling element capable of cooling the temperature of the oven compartment and its circuit components to the desired narrow temperature range.

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Automation & Control Theory (AREA)
  • Oscillators With Electromechanical Resonators (AREA)
  • Geophysics And Detection Of Objects (AREA)
  • Measurement Of Unknown Time Intervals (AREA)
  • Control Of Temperature (AREA)

Abstract

Afin d'obtenir des signaux de référence de temps précis et stables permettant de commander et de faire fonctionner un instrument de radiocarottage (12), une enceinte (14) d'isolation thermique définit une cavité interne (16) destinée à contenir et à protéger une base de temps électronique (10). Une horloge électronique (10), telle qu'un oscillateur à quartz, située dans la cavité (16) de l'enceinte, est électroniquement stable dans une plage de températures prédéterminée légèrement plus élevée que la température ambiante la plus haute détectée dans le puit de sondage. Un élément de chauffage (18), un circuit de commande (22) et un capteur de température (24) sont prévus dans la cavité (16) afin de maintenir l'horloge (10) en deçà de la plage de températures prédéterminée. Un élément de refroidissement (20) automatiquement excité peut également être placé dans la cavité (16) de l'enceinte afin de permettre une régulation supplémentaire de la température.
PCT/US1993/010932 1992-11-13 1993-11-11 Base de temps stabilisee par rapport aux temperatures elevees WO1994011763A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
EP94902231A EP0635137A4 (fr) 1992-11-13 1993-11-11 Base de temps stabilisee par rapport aux temperatures elevees.
NO942573A NO942573D0 (no) 1992-11-13 1994-07-08 Stabilisert tidskrets for brönnloggingsinstrument

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US97588292A 1992-11-13 1992-11-13
US07/975,882 1992-11-13

Publications (1)

Publication Number Publication Date
WO1994011763A1 true WO1994011763A1 (fr) 1994-05-26

Family

ID=25523531

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US1993/010932 WO1994011763A1 (fr) 1992-11-13 1993-11-11 Base de temps stabilisee par rapport aux temperatures elevees

Country Status (4)

Country Link
EP (1) EP0635137A4 (fr)
CA (1) CA2127809A1 (fr)
NO (1) NO942573D0 (fr)
WO (1) WO1994011763A1 (fr)

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1998024695A2 (fr) * 1996-12-06 1998-06-11 Corning Incorporated Boitier pour composants optiques plans thermosensibles
EP0929206A2 (fr) * 1997-12-19 1999-07-14 Lucent Technologies Inc. Boítier thermique pour circuits optiques
WO2000024128A1 (fr) * 1998-10-21 2000-04-27 Symmetricom, Inc. Oscillateur a quartz thermostate a refroidisseur thermoelectrique
WO2002001161A3 (fr) * 2000-06-23 2002-04-25 Kaiser Electroprec Capteur pouvant fonctionner au-dela de ses limites de temperature ambiante de fonctionnement
EP1476796A1 (fr) * 2002-02-02 2004-11-17 Acr Electronics, Inc. Oscillateur dote d'un circuit de stabilisation de frequence et procede de realisation correspondant
EP2171206A2 (fr) * 2007-08-02 2010-04-07 Baker Hughes Incorporated Applications en fond de trou de composites ayant des nanotubes alignés pour le transport de chaleur
US7717167B2 (en) 2004-12-03 2010-05-18 Halliburton Energy Services, Inc. Switchable power allocation in a downhole operation
CN102458083A (zh) * 2010-10-29 2012-05-16 北京师范大学 嵌入式保温箱及保温控制板
US20120299662A1 (en) * 2010-04-27 2012-11-29 Shanfield Stanley R Devices, systems, and methods for controlling the temperature of resonant elements
CN102458083B (zh) * 2010-10-29 2016-12-14 北京师范大学 嵌入式保温箱及保温控制板
US10280739B2 (en) 2014-12-05 2019-05-07 Halliburton Energy Services, Inc. Downhole clock calibration apparatus, systems, and methods
EP3869692A1 (fr) * 2020-02-21 2021-08-25 Stmicroelectronics (Grenoble 2) Sas Compensation de dérive de frequence
US11533019B2 (en) 2020-02-21 2022-12-20 STMicroelectronics (Alps) SAS Drift compensation

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110597317A (zh) * 2019-09-24 2019-12-20 国网江苏省电力有限公司电力科学研究院 一种用于标准时钟装置的温度柔性可调恒温槽

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2167630A (en) * 1936-04-02 1939-08-01 Sperry Sun Well Surveying Co Electrical prospecting method and apparatus
US2433554A (en) * 1942-10-27 1947-12-30 Texas Co Well logging apparatus
US2507351A (en) * 1945-11-23 1950-05-09 Well Surveys Inc Transmitting of information in drill holes
US2709753A (en) * 1941-10-01 1955-05-31 Schlumberger Well Surv Corp Temperature compensated bore hole radioactivity apparatus
US2760078A (en) * 1952-05-27 1956-08-21 Well Surveys Inc Conduction counter for radioactivity well logging
US2942461A (en) * 1955-12-16 1960-06-28 Texaco Inc Well bore hole logging
US3038074A (en) * 1959-11-06 1962-06-05 Serge A Scherbatskoy Temperature-regulated well-logging apparatus
US3167653A (en) * 1962-11-29 1965-01-26 Jersey Prod Res Co Cooling radiation detectors in well logging apparatus
US3265893A (en) * 1963-06-13 1966-08-09 Pgac Dev Company Temperature stabilized radioactivity well logging unit
US3925749A (en) * 1973-09-24 1975-12-09 Western Co Of North America Asynthronous pulse telemetry system and method
US4157466A (en) * 1978-07-31 1979-06-05 Herrin James R Crystal oven for maintaining crystals at a predetermined temperature
US4216371A (en) * 1978-03-03 1980-08-05 Compagnie D'electronique Et De Piezoelectricite C.E.P.E. Device for heat regulation of an enclosure particularly for oscillating piezoelectric crystal, and enclosure comprising such a device
US4230945A (en) * 1978-04-24 1980-10-28 Meir Vladimir A Device for detecting ionizing radiation
US4517459A (en) * 1981-11-02 1985-05-14 Texaco Inc. Temperature stabilization system for a radiation detector in a well logging tool

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0310863B1 (fr) * 1987-09-28 1992-06-10 Siemens Aktiengesellschaft Procédé de compensation en température d'un oscillateur à quartz commandé en tension dans une boucle d'asservissement de phase
US4967166A (en) * 1989-12-07 1990-10-30 Schlumberger Technology Corporation Crystal oscillator and method for mounting the same

Patent Citations (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2167630A (en) * 1936-04-02 1939-08-01 Sperry Sun Well Surveying Co Electrical prospecting method and apparatus
US2709753A (en) * 1941-10-01 1955-05-31 Schlumberger Well Surv Corp Temperature compensated bore hole radioactivity apparatus
US2433554A (en) * 1942-10-27 1947-12-30 Texas Co Well logging apparatus
US2507351A (en) * 1945-11-23 1950-05-09 Well Surveys Inc Transmitting of information in drill holes
US2760078A (en) * 1952-05-27 1956-08-21 Well Surveys Inc Conduction counter for radioactivity well logging
US2942461A (en) * 1955-12-16 1960-06-28 Texaco Inc Well bore hole logging
US3038074A (en) * 1959-11-06 1962-06-05 Serge A Scherbatskoy Temperature-regulated well-logging apparatus
US3167653A (en) * 1962-11-29 1965-01-26 Jersey Prod Res Co Cooling radiation detectors in well logging apparatus
US3265893A (en) * 1963-06-13 1966-08-09 Pgac Dev Company Temperature stabilized radioactivity well logging unit
US3925749A (en) * 1973-09-24 1975-12-09 Western Co Of North America Asynthronous pulse telemetry system and method
US4216371A (en) * 1978-03-03 1980-08-05 Compagnie D'electronique Et De Piezoelectricite C.E.P.E. Device for heat regulation of an enclosure particularly for oscillating piezoelectric crystal, and enclosure comprising such a device
US4230945A (en) * 1978-04-24 1980-10-28 Meir Vladimir A Device for detecting ionizing radiation
US4157466A (en) * 1978-07-31 1979-06-05 Herrin James R Crystal oven for maintaining crystals at a predetermined temperature
US4517459A (en) * 1981-11-02 1985-05-14 Texaco Inc. Temperature stabilization system for a radiation detector in a well logging tool

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP0635137A4 *

Cited By (26)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1998024695A2 (fr) * 1996-12-06 1998-06-11 Corning Incorporated Boitier pour composants optiques plans thermosensibles
WO1998024695A3 (fr) * 1996-12-06 1998-07-23 Corning Incoporated Boitier pour composants optiques plans thermosensibles
US5919383A (en) * 1996-12-06 1999-07-06 Corning Incorporated Package for a temperature-sensitive optical component with inner and outer containers and resistive element therein
EP0929206A2 (fr) * 1997-12-19 1999-07-14 Lucent Technologies Inc. Boítier thermique pour circuits optiques
US5994679A (en) * 1997-12-19 1999-11-30 Lucent Technologies Inc. Thermal housing for optical circuits
EP0929206A3 (fr) * 1997-12-19 2001-02-28 Lucent Technologies Inc. Boítier thermique pour circuits optiques
WO2000024128A1 (fr) * 1998-10-21 2000-04-27 Symmetricom, Inc. Oscillateur a quartz thermostate a refroidisseur thermoelectrique
WO2002001161A3 (fr) * 2000-06-23 2002-04-25 Kaiser Electroprec Capteur pouvant fonctionner au-dela de ses limites de temperature ambiante de fonctionnement
AU2002357694B2 (en) * 2002-02-02 2007-04-05 Acr Electronics, Inc. Oscillator with frequency stabilizing circuit and method of constructing same
EP1476796A1 (fr) * 2002-02-02 2004-11-17 Acr Electronics, Inc. Oscillateur dote d'un circuit de stabilisation de frequence et procede de realisation correspondant
EP1746728A2 (fr) * 2002-02-11 2007-01-24 Acr Electronics, Inc. Oscillateur doté d'un circuit de stabilisation de fréquence et procédé de réalisation correspondant
EP1746728A3 (fr) * 2002-02-11 2007-02-14 Acr Electronics, Inc. Oscillateur doté d'un circuit de stabilisation de fréquence et procédé de réalisation correspondant
EP1476796A4 (fr) * 2002-02-11 2005-08-10 Acr Electronics Oscillateur dote d'un circuit de stabilisation de frequence et procede de realisation correspondant
US7717167B2 (en) 2004-12-03 2010-05-18 Halliburton Energy Services, Inc. Switchable power allocation in a downhole operation
EP2171206A4 (fr) * 2007-08-02 2013-11-27 Baker Hughes Inc Applications en fond de trou de composites ayant des nanotubes alignés pour le transport de chaleur
EP2171206A2 (fr) * 2007-08-02 2010-04-07 Baker Hughes Incorporated Applications en fond de trou de composites ayant des nanotubes alignés pour le transport de chaleur
US20120299662A1 (en) * 2010-04-27 2012-11-29 Shanfield Stanley R Devices, systems, and methods for controlling the temperature of resonant elements
US8653897B2 (en) * 2010-04-27 2014-02-18 The Charles Stark Draper Laboratory, Inc. Devices, systems, and methods for controlling the temperature of resonant elements
CN102458083A (zh) * 2010-10-29 2012-05-16 北京师范大学 嵌入式保温箱及保温控制板
CN102458083B (zh) * 2010-10-29 2016-12-14 北京师范大学 嵌入式保温箱及保温控制板
US10280739B2 (en) 2014-12-05 2019-05-07 Halliburton Energy Services, Inc. Downhole clock calibration apparatus, systems, and methods
EP3869692A1 (fr) * 2020-02-21 2021-08-25 Stmicroelectronics (Grenoble 2) Sas Compensation de dérive de frequence
FR3107628A1 (fr) * 2020-02-21 2021-08-27 Stmicroelectronics (Grenoble 2) Sas Compensation de dérive
US11239796B2 (en) 2020-02-21 2022-02-01 Stmicroelectronics S.R.L. Drift compensation
US11533019B2 (en) 2020-02-21 2022-12-20 STMicroelectronics (Alps) SAS Drift compensation
US11764731B2 (en) 2020-02-21 2023-09-19 STMicroelectronics (Alps) SAS Drift compensation

Also Published As

Publication number Publication date
EP0635137A1 (fr) 1995-01-25
NO942573L (no) 1994-07-08
CA2127809A1 (fr) 1994-05-26
EP0635137A4 (fr) 1995-04-19
NO942573D0 (no) 1994-07-08

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