CN104612672A - Signal processing system for nuclear magnetic resonance logging instrument - Google Patents
Signal processing system for nuclear magnetic resonance logging instrument Download PDFInfo
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- CN104612672A CN104612672A CN201510009321.2A CN201510009321A CN104612672A CN 104612672 A CN104612672 A CN 104612672A CN 201510009321 A CN201510009321 A CN 201510009321A CN 104612672 A CN104612672 A CN 104612672A
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- 238000005481 NMR spectroscopy Methods 0.000 title claims abstract description 24
- 238000012545 processing Methods 0.000 title claims abstract description 17
- 230000003321 amplification Effects 0.000 claims abstract description 34
- 238000003199 nucleic acid amplification method Methods 0.000 claims abstract description 34
- 238000005070 sampling Methods 0.000 claims abstract description 30
- 230000000052 comparative effect Effects 0.000 claims description 15
- 238000000034 method Methods 0.000 claims description 3
- 238000004891 communication Methods 0.000 abstract description 4
- 238000001208 nuclear magnetic resonance pulse sequence Methods 0.000 abstract 2
- 239000000725 suspension Substances 0.000 abstract 1
- 239000000523 sample Substances 0.000 description 13
- 230000015572 biosynthetic process Effects 0.000 description 5
- 238000010586 diagram Methods 0.000 description 3
- 238000005259 measurement Methods 0.000 description 3
- 230000005540 biological transmission Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000012937 correction Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000008030 elimination Effects 0.000 description 1
- 238000003379 elimination reaction Methods 0.000 description 1
- 210000002445 nipple Anatomy 0.000 description 1
- 238000005086 pumping Methods 0.000 description 1
Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B49/00—Testing the nature of borehole walls; Formation testing; Methods or apparatus for obtaining samples of soil or well fluids, specially adapted to earth drilling or wells
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- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Geology (AREA)
- Mining & Mineral Resources (AREA)
- Physics & Mathematics (AREA)
- Environmental & Geological Engineering (AREA)
- Fluid Mechanics (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Geophysics And Detection Of Objects (AREA)
- Magnetic Resonance Imaging Apparatus (AREA)
Abstract
The invention relates to a signal processing system for a nuclear magnetic resonance logging instrument, in particular to an extended cable signal processing system. The signal processing system comprises a communication circuit, a pulse sequence generating circuit and a power amplification circuit, wherein the communication circuit, the pulse sequence generating circuit and the power amplification circuit are sequentially connected. The signal processing system is characterized by further comprising a current sampling and processing circuit. A current signal of the output end of the power amplification circuit of the nuclear magnetic resonance logging instrument is received by the input end of the current sampling and processing circuit. A comparing result of the current sampling signal and a first set threshold value and/or a second set threshold value is regarded as a set controlling signal and output from the output end. The set controlling signal is received by the controlling end of the communication circuit, the set controlling signal is processed according to a predetermined rule to be converted into a power signal, and the power signal is output from the output end. Therefore, the instrument and the power amplification circuit are protected, the strata measuring range of the instrument is extended, and financial losses caused by logging operation suspension are avoided.
Description
Technical field
The present invention relates to expansion cable signal processing system, particularly relate to a kind of signal processing system for NMR (Nuclear Magnetic Resonance) logging instrument.
Background technology
As shown in Figure 1, comprise the communicating circuit, pulse train circuit for generating and the power amplification circuit that are connected successively, power amplification circuit loop comprises high-power resistance R1 and R2 and antenna to current NMR (Nuclear Magnetic Resonance) logging instrument, and wherein communicating circuit communicates with ground system.As shown in Figure 1, the NMR (Nuclear Magnetic Resonance) logging instrument of prior art adopts probe to separate with circuit pipe nipple and designs, and by popping one's head in, the NMR signal received just need can reach treatment circuit through longer distance.Because NMR signal is very faint, the pumping signal of some strength could produce the echo-signal that quality carries formation information preferably, and the radiating circuit of nuclear magnetic resonance logging instrument is constant voltage transmitting, therefore must ensure the emitting voltage that instrument is certain.Due to the power limit of device, in well logging, the reduction of the mud resistivity of ground environment can make the power amplification circuit electric current of instrument increase, even damage radiating circuit, thus interruption logging operation, can not get corresponding formation information, cause very large economic loss.
At present; only radiating circuit is protected in existing scheme; the transmitting of instrument is interrupted immediately after the electric current in radiating circuit loop exceeds normal range (NR), now can the formation information that obtains of lost part, and wish in practical logging to obtain continuous print formation information complete as far as possible.
Summary of the invention
The technical problem to be solved in the present invention overcomes current NMR signal cannot carry out the defect of continuous logging operation because stratum mud resistivity reduces suddenly.
In order to solve the problems of the technologies described above, the invention provides a kind of signal processing system for NMR (Nuclear Magnetic Resonance) logging instrument, comprise the communicating circuit, pulse train circuit for generating and the power amplification circuit that are connected successively, also comprising: current sample and treatment circuit;
Described current sample and treatment circuit input receive the current signal of power amplification circuit output in described NMR (Nuclear Magnetic Resonance) logging instrument, current sampling signal and first are set the comparative result that threshold value and/or second sets threshold value and export from output as setup control signal;
The control end of described communicating circuit receives described setup control signal, processes described setup control signal according to pre-defined rule, forms power signal, exports described power signal from output.
Preferably, described current sample and treatment circuit comprise: current sampling circuit, current levels circuit;
The input of described current sampling circuit receives the current signal of power amplification circuit output in described NMR (Nuclear Magnetic Resonance) logging instrument, output output current sampled signal;
The input of described current levels circuit receives described current sampling signal, the first setting threshold value and the second setting threshold value, current sampling signal and first is set the comparative result that threshold value and/or second sets threshold value and exports from output as setup control signal.
Preferably, described first setting threshold value is greater than the second setting threshold value:
When described current sampling signal is less than or equal to described second setting threshold value, the comparative result of the output of described current levels circuit is normal signal, described communicating circuit keeps current power signal, exports current power signal to described pulse train circuit for generating as power signal;
When described current sampling signal is greater than described second setting threshold value and is less than or equal to described first setting threshold value, the comparative result of the output of described current levels circuit is early warning signal, described communicating circuit reduces current power signal, exports the current power signal after reducing to pulse train circuit for generating as power signal;
When described current sampling signal is greater than described first setting threshold value, the comparative result of the output of described current levels circuit is over-current signal, and described communicating circuit stops power output signal to described pulse train circuit for generating.
Preferably, described system also comprises control circuit,
The input of described control circuit receives the power amplifier control signal of described pulse train circuit for generating, amplifies output signal to described power amplification circuit from output power output.
Preferably, the control end of described control circuit receives described over-current signal, and after receiving described over-current signal, stops power output amplifying output signal.
Preferably, the reset terminal of described control circuit receives the reset signal of described communicating circuit, and after receiving described reset signal, recovers power output and amplify output signal.
Compared with prior art; the signal processing apparatus of the embodiment of the present invention; the mud resistivity scope of current Log Strata is obtained by the measurement of electric current; when power amplification circuit current anomaly; protection instrument and power amplification circuit, ground system carries out respective handling, enables instrument proceed logging operation; extend the scope of instrument institute geodetic layer, avoid the economic loss caused because logging operation interrupts.
Accompanying drawing explanation
Fig. 1 is a kind of structural representation for NMR (Nuclear Magnetic Resonance) logging instrument of prior art;
Fig. 2 is the connection diagram of the signal processing system for NMR (Nuclear Magnetic Resonance) logging instrument of the embodiment of the present invention;
Fig. 3 is the current sample of the embodiment of the present invention and the structural representation for the treatment of circuit;
Fig. 4 is the current sample of the embodiment of the present invention and the annexation figure for the treatment of circuit;
Fig. 5 is the control circuit operating principle schematic diagram of the embodiment of the present invention.
Detailed description of the invention
For making the object, technical solutions and advantages of the present invention clearly understand, hereinafter will be described in detail to embodiments of the invention by reference to the accompanying drawings.It should be noted that, when not conflicting, the embodiment in the application and the feature in embodiment can be combined mutually.
As shown in Figure 2, a kind of signal processing system for NMR (Nuclear Magnetic Resonance) logging instrument, comprises the communicating circuit, pulse train circuit for generating and the power amplification circuit that are connected successively, also comprises: current sample and treatment circuit;
Described current sample and treatment circuit input receive the current signal of power amplification circuit output in described NMR (Nuclear Magnetic Resonance) logging instrument, current sampling signal and first are set the comparative result that threshold value and/or second sets threshold value and export from output as setup control signal;
The control end of described communicating circuit receives described setup control signal, processes described setup control signal according to pre-defined rule, forms power signal, exports described power signal from output.
As shown in Figure 3, described current sample and treatment circuit comprise: current sampling circuit, current levels circuit;
The input of described current sampling circuit receives the current signal of power amplification circuit output in described NMR (Nuclear Magnetic Resonance) logging instrument, output output current sampled signal;
The input of described current levels circuit receives described current sampling signal, the first setting threshold value and the second setting threshold value, current sampling signal and first is set the comparative result that threshold value and/or second sets threshold value and exports from output as setup control signal.
Wherein, described first setting threshold value is greater than the second setting threshold value:
When described current sampling signal is less than or equal to described second setting threshold value, the comparative result of the output of described current levels circuit is normal signal, described communicating circuit keeps current power signal, exports current power signal to described pulse train circuit for generating as power signal;
When described current sampling signal is greater than described second setting threshold value and is less than or equal to described first setting threshold value, the comparative result of the output of described current levels circuit is early warning signal, described communicating circuit reduces current power signal, exports the current power signal after reducing to pulse train circuit for generating as power signal;
When described current sampling signal is greater than described first setting threshold value, the comparative result of the output of described current levels circuit is over-current signal, and described communicating circuit stops power output signal to described pulse train circuit for generating.
High-power resistance R1 and R2 in power amplification circuit loop is utilized to sample to electric current as current sampling resistor, with current levels circuit, current sampling signal is divided into three ranks: normal, early warning and overcurrent, and export corresponding signal, by instrument communication circuit, early warning signal and over-current signal are sent to ground system.When producing early warning signal, the size of current in power amplification loop exceeds normal range (NR), but can not power amplification circuit be damaged, ground system suitably reduces emitting voltage, and (high voltage source of power amplification circuit is provided by ground high-voltage DC power supply, ground high-voltage DC power supply is powered as 600V under normal circumstances, when early warning signal produces, generally rule of thumb, ground high-voltage DC power supply is powered and is set to 500V, therefore, be reduced to original 83.3%), instrument proceeds logging operation, although emitting voltage does not now reach standard, echo-signal quality is under some influence, but obtain correct formation information by carrying out inverting correction to raw measurement data, when producing over-current signal, the size of current in power amplification loop reaches the degree damaging circuit, ground system stops the input of power amplification circuit control signal, stop the transmitting of antenna, the information provided in conjunction with other instruments or ground system by ground system operating personnel carrys out decision-making, judge that overcurrent Producing reason is that instrument failure or stratum mud resistivity are extremely low, as instrument failure then stops well logging, stratum mud resistivity is extremely low in this way, then after mud resistivity reaches range of safety operation, ground system recovers to export, power amplification circuit recovers normal work, instrument proceeds logging operation.
As shown in Figure 2, a kind of signal processing system for NMR (Nuclear Magnetic Resonance) logging instrument also comprises control circuit,
The input of described control circuit receives the power amplifier control signal of described pulse train circuit for generating, amplifies output signal to described power amplification circuit from output power output.
The control end of described control circuit receives described over-current signal, and after receiving described over-current signal, stops power output amplifying output signal.
The reset terminal of described control circuit receives the reset signal of described communicating circuit, and after receiving described reset signal, recovers power output and amplify output signal.
When producing over-current signal, for stopping power amplification circuit control signal to input fast, controlled by the input of control circuit power amplification circuit.After Failure elimination, control circuit receives reset command, and power amplification circuit recovers normal work.
Embodiment
As shown in Figure 3, current sample and treatment circuit mainly realize the current sample of high pressure radiating circuit and carry out classification to size of current, current sampling signal is divided into three ranks: normal, early warning and overcurrent, corresponding three scopes of stratum mud resistivity: be greater than 0.02 ohm meter, be less than 0.02 ohm meter and be greater than 0.01 ohm meter, be less than 0.01 ohm meter.Under normal circumstances, early warning signal and over-current signal export and are low level, and when sampled signal exceedes early warning or overcurrent threshold voltage, the early warning of corresponding output or over-current signal are the positive pulse signal of fixed pulse width.
As shown in Figure 4, voltage U 1 inputs one group of symmetrical expression RC divider, voltage U 2 inputs the identical divider of another group parameter, divider parameter R3=R5, C1=C3, attenuation ratio is K (K is far smaller than 1), and the Same Name of Ends of two transformers is connected simultaneously, the voltage signal magnitude U3=K (U1-U2) of such input signal processing circuit.Due to transmitting antenna hub of a spool tap ground connection, the differential sample mode of this symmetrical expression resistive-capacitive voltage divider makes in the scope of frequency 500kHz to 1MHz, attenuation ratio K has good uniformity, maintain the symmetry of former transmitting antenna, simultaneously to the resonant frequency of antenna, Q value, the parameters such as impedance operator do not affect substantially.
As shown in Figure 5, be control circuit operating principle schematic diagram, control circuit possesses latch and reset function.When instrument normally works, over-current signal ove_cur and reset signal reset is low level, exports the power amplifier control signal 2output consistent with power amplifier control signal 1input, instrument normal transmission.During radiating circuit (power amplification circuit) overcurrent, power output is amplified control signal 2output and is remained low level state, thus stops the transmitting of instrument, reaches the object of protection radiating circuit.After ground system takes relevant safeguard measure to make over-current signal remain low level; ground system sends reset command reset; remove the data latched, export the power amplifier control signal 2output consistent with power amplifier control signal 1input, instrument recovers normal transmission.
The embodiment of the present invention makes in nuclear magnetic resonance logging instrument well logging; the mud resistivity scope of current Log Strata is obtained by the measurement of electric current; when power amplification circuit current anomaly; protection instrument power amplification circuit; ground system carries out respective handling; enable instrument proceed logging operation, extend the scope of instrument institute geodetic layer, avoid the economic loss caused because logging operation interrupts.
Above embodiment only in order to technical scheme of the present invention and unrestricted to be described, only with reference to preferred embodiment to invention has been detailed description.Those of ordinary skill in the art should be appreciated that and can modify to technical scheme of the present invention or equivalent replacement, and does not depart from the spirit and scope of technical solution of the present invention, all should be encompassed in the middle of right of the present invention.
Claims (6)
1., for a signal processing system for NMR (Nuclear Magnetic Resonance) logging instrument, comprise the communicating circuit, pulse train circuit for generating and the power amplification circuit that are connected successively, it is characterized in that: also comprise: current sample and treatment circuit;
Described current sample and treatment circuit input receive the current signal of power amplification circuit output in described NMR (Nuclear Magnetic Resonance) logging instrument, current sampling signal and first are set the comparative result that threshold value and/or second sets threshold value and export from output as setup control signal;
The control end of described communicating circuit receives described setup control signal, processes described setup control signal according to pre-defined rule, forms power signal, exports described power signal from output.
2. the system as claimed in claim 1, is characterized in that: described current sample and treatment circuit comprise: current sampling circuit, current levels circuit;
The input of described current sampling circuit receives the current signal of power amplification circuit output in described NMR (Nuclear Magnetic Resonance) logging instrument, output output current sampled signal;
The input of described current levels circuit receives described current sampling signal, the first setting threshold value and the second setting threshold value, current sampling signal and first is set the comparative result that threshold value and/or second sets threshold value and exports from output as setup control signal.
3. system as claimed in claim 2, is characterized in that:
Described first setting threshold value is greater than the second setting threshold value:
When described current sampling signal is less than or equal to described second setting threshold value, the comparative result of the output of described current levels circuit is normal signal, described communicating circuit keeps current power signal, exports current power signal to described pulse train circuit for generating as power signal;
When described current sampling signal is greater than described second setting threshold value and is less than or equal to described first setting threshold value, the comparative result of the output of described current levels circuit is early warning signal, described communicating circuit reduces current power signal, exports the current power signal after reducing to pulse train circuit for generating as power signal;
When described current sampling signal is greater than described first setting threshold value, the comparative result of the output of described current levels circuit is over-current signal, and described communicating circuit stops power output signal to described pulse train circuit for generating.
4. system as claimed in claim 3, is characterized in that: also comprise control circuit,
The input of described control circuit receives the power amplifier control signal of described pulse train circuit for generating, amplifies output signal to described power amplification circuit from output power output.
5. system as claimed in claim 4, is characterized in that:
The control end of described control circuit receives described over-current signal, and after receiving described over-current signal, stops power output amplifying output signal.
6. system as claimed in claim 4, is characterized in that:
The reset terminal of described control circuit receives the reset signal of described communicating circuit, and after receiving described reset signal, recovers power output and amplify output signal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510009321.2A CN104612672B (en) | 2015-01-08 | 2015-01-08 | A kind of signal processing system for NMR logging instrument |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510009321.2A CN104612672B (en) | 2015-01-08 | 2015-01-08 | A kind of signal processing system for NMR logging instrument |
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| Publication Number | Publication Date |
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| CN104612672A true CN104612672A (en) | 2015-05-13 |
| CN104612672B CN104612672B (en) | 2017-06-30 |
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Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3459955A (en) * | 1966-08-02 | 1969-08-05 | Schlumberger Technology Corp | Electric power transmission system for well logging |
| CN1077775A (en) * | 1992-04-15 | 1993-10-27 | 胜利石油管理局测井公司 | Full-electrode logging method |
| CN201202473Y (en) * | 2008-05-30 | 2009-03-04 | 北京华能通达能源科技有限公司 | Magnetic nuclear resonance logger |
| CN201221353Y (en) * | 2008-06-11 | 2009-04-15 | 中国石油集团钻井工程技术研究院 | Downhole wireless electromagnetic transmitting apparatus |
| CN201549882U (en) * | 2009-11-12 | 2010-08-11 | 中国北车股份有限公司大连电力牵引研发中心 | Insulated gate dipole transistor protection device |
| CN202856693U (en) * | 2012-09-27 | 2013-04-03 | 中国海洋石油总公司 | Power amplifying circuit of underground nuclear magnetic resonance logging instrument |
| CN103117717A (en) * | 2012-12-11 | 2013-05-22 | 中国电子科技集团公司第二十二研究所 | Power amplifier and implementing method thereof, transmitter and wireless measurement while drilling system |
| CN104009445A (en) * | 2012-09-20 | 2014-08-27 | 英飞凌科技股份有限公司 | Semiconductor device including short-circuit protection |
| CN203951161U (en) * | 2014-06-03 | 2014-11-19 | 成都嘉晨科技有限公司 | A kind of overcurrent monitoring protective circuit |
| CN204068793U (en) * | 2014-08-27 | 2014-12-31 | 西京学院 | A kind of used in oil well logging pushing device digitlization current control circuit |
-
2015
- 2015-01-08 CN CN201510009321.2A patent/CN104612672B/en active Active
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3459955A (en) * | 1966-08-02 | 1969-08-05 | Schlumberger Technology Corp | Electric power transmission system for well logging |
| CN1077775A (en) * | 1992-04-15 | 1993-10-27 | 胜利石油管理局测井公司 | Full-electrode logging method |
| CN201202473Y (en) * | 2008-05-30 | 2009-03-04 | 北京华能通达能源科技有限公司 | Magnetic nuclear resonance logger |
| CN201221353Y (en) * | 2008-06-11 | 2009-04-15 | 中国石油集团钻井工程技术研究院 | Downhole wireless electromagnetic transmitting apparatus |
| CN201549882U (en) * | 2009-11-12 | 2010-08-11 | 中国北车股份有限公司大连电力牵引研发中心 | Insulated gate dipole transistor protection device |
| CN104009445A (en) * | 2012-09-20 | 2014-08-27 | 英飞凌科技股份有限公司 | Semiconductor device including short-circuit protection |
| CN202856693U (en) * | 2012-09-27 | 2013-04-03 | 中国海洋石油总公司 | Power amplifying circuit of underground nuclear magnetic resonance logging instrument |
| CN103117717A (en) * | 2012-12-11 | 2013-05-22 | 中国电子科技集团公司第二十二研究所 | Power amplifier and implementing method thereof, transmitter and wireless measurement while drilling system |
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| CN204068793U (en) * | 2014-08-27 | 2014-12-31 | 西京学院 | A kind of used in oil well logging pushing device digitlization current control circuit |
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| CN104612672B (en) | 2017-06-30 |
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Address after: 100010 Chaoyangmen North Street, Dongcheng District, Dongcheng District, Beijing Co-patentee after: China Oilfield Services Limited Patentee after: China Offshore Oil Group Co., Ltd. Address before: 100010 Chaoyangmen North Street, Dongcheng District, Dongcheng District, Beijing Co-patentee before: China Oilfield Services Limited Patentee before: China National Offshore Oil Corporation |