CN113062728B - Real-time wireless receiving method and system for while-drilling data of deep coal drilling - Google Patents
Real-time wireless receiving method and system for while-drilling data of deep coal drilling Download PDFInfo
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- CN113062728B CN113062728B CN202110341835.3A CN202110341835A CN113062728B CN 113062728 B CN113062728 B CN 113062728B CN 202110341835 A CN202110341835 A CN 202110341835A CN 113062728 B CN113062728 B CN 113062728B
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- 238000005553 drilling Methods 0.000 title claims abstract description 55
- 239000003245 coal Substances 0.000 title claims abstract description 32
- 238000000034 method Methods 0.000 title claims abstract description 26
- 238000004891 communication Methods 0.000 abstract description 9
- 238000012545 processing Methods 0.000 description 8
- 230000005540 biological transmission Effects 0.000 description 6
- 230000007613 environmental effect Effects 0.000 description 5
- 238000005065 mining Methods 0.000 description 4
- 230000008901 benefit Effects 0.000 description 3
- 230000002238 attenuated effect Effects 0.000 description 2
- 238000003384 imaging method Methods 0.000 description 2
- 230000002401 inhibitory effect Effects 0.000 description 2
- 230000001629 suppression Effects 0.000 description 2
- 230000003321 amplification Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000003199 nucleic acid amplification method Methods 0.000 description 1
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
- H04B1/06—Receivers
- H04B1/10—Means associated with receiver for limiting or suppressing noise or interference
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02D—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
- Y02D30/00—Reducing energy consumption in communication networks
- Y02D30/70—Reducing energy consumption in communication networks in wireless communication networks
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Abstract
The invention provides a real-time wireless receiving method and system for while-drilling data of deep coal drilling. The invention relates to a real-time wireless receiving method for data while drilling of deep coal drilling, which mainly adopts the following steps to process received electromagnetic signals: s1: a high-pass filter is adopted to inhibit natural potential and magnetotelluric signals with the frequency below 0.1 Hz; s2: reducing the amplitude of the power frequency interference signal to be below millivolt level by adopting a first-level low-pass filter; s3: a second-stage low-pass filter is adopted to inhibit the power frequency interference signal; s4: adopting a three-stage low-pass filter to inhibit a power supply noise signal; s5: a digital filter is used to reject out-of-band noise. The method and the system can effectively inhibit the interference noise signals, so that the useful electromagnetic communication signals are extracted, the method and the system can stably operate in deep high-pressure complex environments, the efficiency of drilling work is improved on the whole, and meanwhile, the safety of underground engineering operation is improved.
Description
Technical Field
The invention relates to the technical field of data receiving and processing, in particular to a real-time wireless receiving method and system for data while drilling of deep coal drilling.
Background
The geological environment of underground coal mining activities is complex, and many technical problems are to be solved and perfected. In particular to drilling work during deep coal exploitation, drilling data is required to be acquired in the shortest time during drilling, and meanwhile, drilling states are required to be rapidly analyzed to guide safe production. The most prominent problem is how to receive the transmitted data in real time and without loss.
Based on the existing wireless transmission mode of the data while drilling: the existing signal receiving technology has been greatly developed in the drilling fluid pulse wireless transmission mode, the acoustic wave wireless transmission mode, the electromagnetic wave wireless transmission mode based on the drill rod and the stratum, etc., but in most cases, the period of receiving and reprocessing after the signal arrives is longer, and the interference of natural potential, environmental noise, etc. is larger, so that the high-efficiency stable real-time receiving of the transmission signal under the high-low pressure complex environment is difficult to realize.
Therefore, it is necessary to provide a wireless receiving method and system for data while drilling, which are suitable for the exploitation work of deep high-pressure complex environments of coal, stable in work, and capable of effectively filtering interference signals and extracting effective electromagnetic transmission signals.
Disclosure of Invention
The invention aims to provide a real-time wireless receiving method and system for data while drilling of deep coal drilling, which can effectively inhibit interference noise signals, so that useful electromagnetic communication signals are extracted and can stably operate in a deep high-pressure complex environment, and the efficiency of drilling work is improved as a whole.
The invention provides a real-time wireless receiving method for data while drilling of deep coal drilling, which mainly adopts the following steps of:
s1: a high-pass filter is adopted to inhibit natural potential and magnetotelluric signals with the frequency below 0.1 Hz;
S2: reducing the amplitude of the power frequency interference signal to be below millivolt level by adopting a first-level low-pass filter;
s3: a second-stage low-pass filter is adopted to inhibit the power frequency interference signal;
S4: adopting a three-stage low-pass filter to inhibit a power supply noise signal;
S5: a digital filter is used to reject out-of-band noise.
The research finds that: the electromagnetic signals received by the receiving electrodes arranged at the underground coal mine holes actually comprise the electromagnetic signals which are attenuated and interference noise signals, wherein the interference noise signals mainly comprise natural electric potentials and environmental noises existing between the electrodes, and the environmental noises comprise electromagnetic noises, power lines and artificial noises of field machinery. The method of the invention adopts the multistage filter to complete interference noise signal suppression, thereby extracting weak target electromagnetic communication signals; specifically, the method adopts an analog high-pass filter to inhibit the magnetotelluric signals with the frequency below 0.1Hz, including natural potential signals, adopts an analog low-pass filter to inhibit 50Hz power frequency interference and frequency multiplication interference thereof, and subsequently adopts a digital filter to further inhibit out-of-band noise signals.
Further, a pre-amplifier is adopted before the first-stage low-pass filter is processed; in particular, the pre-amplifier may employ an instrumentation amplifier with low voltage offset, low tone drift, low gain drift, high quality accuracy, and high common mode rejection ratio characteristics.
Further, after the primary low-pass filter, the secondary low-pass filter and the tertiary low-pass filter are processed, the primary main amplifier, the secondary main amplifier and the tertiary main amplifier are adopted for amplification respectively; the maximum gain of the primary main amplifier, the secondary main amplifier and the tertiary main amplifier is 100 times.
The method provided by the invention can stably filter the interference noise signals, accurately extract the useful target electromagnetic communication signals, is applicable to mining work of deep high-pressure complex environments of coal, and improves the safety and the working efficiency of underground engineering operation.
The invention also provides a real-time wireless receiving system for the while-drilling data of the coal deep drilling, which comprises an analog filter and a digital filter which are sequentially arranged, wherein the analog filter comprises a high-pass filter, a first-stage low-pass filter, a second-stage low-pass filter and a third-stage low-pass filter which are sequentially arranged, the high-pass filter can inhibit natural potential and the magnetotelluric signals with the frequency lower than 0.1Hz, the first-stage low-pass filter can reduce the amplitude of the power frequency interference signals to the level lower than millivolts, the second-stage low-pass filter can inhibit the power frequency interference signals, the third-stage low-pass filter can inhibit the power supply noise signals, and the digital filter can inhibit out-of-band noise.
Further, a pre-amplifier is provided between the high-pass filter and the first-stage low-pass filter.
Further, a primary main amplifier is arranged between the primary low-pass filter and the secondary low-pass filter.
Further, a second-stage main amplifier is arranged between the second-stage low-pass filter and the third-stage low-pass filter.
Further, a three-stage main amplifier and an A/D converter are sequentially arranged between the three-stage low-pass filter and the digital filter.
Furthermore, the real-time wireless receiving system for the while-drilling data of the coal deep drilling also comprises a receiving electrode for receiving electromagnetic signals.
The real-time wireless receiving system for the while-drilling data of the deep coal drilling can be arranged in the explosion-proof computer or connected with the explosion-proof computer.
The implementation of the invention has at least the following advantages:
1. The real-time wireless receiving system for the data while drilling of the deep coal drilling has the advantages of simple structure, low cost and high efficiency;
2. The real-time wireless receiving method and system for the while-drilling data of the deep coal drilling can effectively inhibit interference noise signals, so that useful electromagnetic communication signals are extracted;
3. The real-time wireless receiving method and system for the while-drilling data of the deep coal drilling can stably operate in a deep high-pressure complex environment;
4. The real-time wireless receiving method and system for the while-drilling data of the deep coal drilling can improve the drilling work efficiency and the economic benefit.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are needed in the description of the embodiments or the prior art will be briefly described, and it is obvious that the drawings in the description below are some embodiments of the present invention, and other drawings can be obtained according to the drawings without inventive effort for a person skilled in the art.
Fig. 1 is a flowchart of a method for wireless receiving while-drilling data of a deep coal borehole according to an embodiment of the present invention.
Detailed Description
The technical solutions of the present invention will be clearly and completely described in connection with the embodiments, and it is apparent that the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings are merely for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present invention.
Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more of the described features. In the description of the present invention, the meaning of "a plurality" is two or more, unless explicitly defined otherwise. Furthermore, the terms "mounted," "connected," "coupled," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present invention will be understood in specific cases by those of ordinary skill in the art.
Example 1
Referring to fig. 1, the embodiment provides a real-time wireless receiving method for data while drilling of deep coal drilling, which is performed by adopting a multistage filter, and specifically comprises the following steps:
S1: receiving electromagnetic signals
Specifically, the receiving electrode arranged at the underground coal mine hole is used for receiving the electromagnetic signals sent by the transmitting module, the electromagnetic signals actually comprise the electromagnetic signals which are attenuated and interference noise signals, the interference noise signals mainly comprise natural potential and environmental noise existing between the electrodes, and the environmental noise comprises electromagnetic noise, power lines and artificial noise of field machinery.
S2: high pass filter processing
Firstly, the electromagnetic signals received by the receiving electrode are processed by adopting a high-pass filter, and the high-pass filter is mainly used for inhibiting natural potential and magnetotelluric signals with the frequency lower than 0.1 Hz.
S3: preamplifier processing
Then, amplifying the electromagnetic signal processed by the high-pass filter by adopting a preamplifier; the preamplifier adopts an instrument amplifier with low voltage offset, low electric tuning drift, low gain drift, high quality precision and high common mode rejection ratio.
S4: low pass filter processing
Firstly, a first-stage low-pass filter is adopted to process electromagnetic signals processed by a pre-amplifier, and then a first-stage main amplifier is adopted to amplify the electromagnetic signals; the first-stage low-pass filter is mainly used for reducing the amplitude of the power frequency interference signal to be below millivolt level.
Then, a second-stage low-pass filter is adopted to process the electromagnetic signals processed by the first-stage main amplifier, and then the second-stage main amplifier is adopted to amplify the electromagnetic signals; the second-level low-pass filter is mainly used for inhibiting power frequency interference signals.
Then, a three-stage low-pass filter is adopted to process the electromagnetic signals processed by the two-stage main amplifier, and then the three-stage main amplifier is adopted to amplify the electromagnetic signals; the three-stage low-pass filter is mainly used for suppressing power supply noise signals.
The maximum gains of the primary main amplifier, the secondary main amplifier and the tertiary main amplifier are all 100 times.
S5: digital filter processing
The electromagnetic signal processed by the three-stage main amplifier is subjected to A/D conversion, and then a digital filter is adopted to suppress out-of-band noise.
After the processing of the multistage filter, the interference noise signal suppression is completed, the weak target electromagnetic communication signal is extracted, and finally, the final processing and imaging are carried out through an explosion-proof computer.
The method can stably filter the interference noise signals, accurately extract useful target electromagnetic communication signals, is applicable to mining work of deep high-pressure complex environments of coal, and improves safety and working efficiency of underground engineering operation.
Example 2
The embodiment provides a real-time wireless receiving system for data while drilling of coal deep drilling, which comprises an analog filter and a digital filter which are sequentially arranged, wherein the analog filter comprises a high-pass filter, a first-stage low-pass filter, a second-stage low-pass filter and a third-stage low-pass filter which are sequentially arranged, the high-pass filter can inhibit natural potential and magnetotelluric signals below 0.1Hz frequency, the first-stage low-pass filter can reduce the amplitude of power frequency interference signals to below millivolt, the second-stage low-pass filter can inhibit power frequency interference signals, the third-stage low-pass filter can inhibit power supply noise signals, and the digital filter can inhibit out-of-band noise.
Further, a preamplifier is arranged between the high-pass filter and the first-stage low-pass filter, and an instrument amplifier with low voltage offset, low electric tuning drift, low gain drift, high quality precision and high common mode rejection ratio characteristic is adopted; meanwhile, a primary main amplifier is arranged between the primary low-pass filter and the secondary low-pass filter, a secondary main amplifier is arranged between the secondary low-pass filter and the tertiary low-pass filter, a tertiary main amplifier and an A/D converter are sequentially arranged between the tertiary low-pass filter and the digital filter, and the maximum gains of the primary main amplifier, the secondary main amplifier and the tertiary main amplifier are all 100 times.
It can be appreciated that the coal deep drilling while-drilling data real-time wireless receiving system can further comprise a receiving electrode for receiving electromagnetic signals.
The real-time wireless receiving system for the while-drilling data of the deep coal drilling can be arranged in the explosion-proof computer or connected with the explosion-proof computer, so that the explosion-proof computer is utilized to carry out final processing and imaging.
According to the real-time wireless receiving system for the data while drilling of the coal deep drilling, the analog high-pass filter is adopted to inhibit the magnetotelluric signals with the frequency below 0.1Hz and comprises natural potential signals, then the analog low-pass filter is adopted to inhibit the 50Hz power frequency interference and the frequency multiplication interference thereof, and then the digital filter is adopted to further inhibit out-of-band noise signals, so that the interference noise signals are stably filtered, useful target electromagnetic communication signals are accurately extracted, the system is suitable for mining work of the coal deep high-pressure complex environment, and the safety and the working efficiency of underground engineering work are improved.
Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present invention, and not for limiting the same; although the invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the invention.
Claims (4)
1. A real-time wireless receiving method for data while drilling of deep coal drilling is characterized in that the method mainly adopts the following steps to process received electromagnetic signals:
s1: a high-pass filter is adopted to inhibit natural potential and magnetotelluric signals with the frequency below 0.1 Hz;
S2: reducing the amplitude of the power frequency interference signal to be below millivolt level by adopting a first-level low-pass filter;
s3: a second-stage low-pass filter is adopted to inhibit the power frequency interference signal;
S4: adopting a three-stage low-pass filter to inhibit a power supply noise signal;
s5: suppressing out-of-band noise by adopting a digital filter;
A pre-amplifier is adopted before the first-stage low-pass filter is processed; the first-stage low-pass filter, the second-stage low-pass filter and the third-stage low-pass filter are respectively adopted to amplify after being processed; the maximum gain of the primary main amplifier, the secondary main amplifier and the tertiary main amplifier is 100 times.
2. The real-time wireless receiving system for the while-drilling data of the coal deep drilling is characterized by comprising an analog filter and a digital filter which are sequentially arranged, wherein the analog filter comprises a high-pass filter, a first-stage low-pass filter, a second-stage low-pass filter and a third-stage low-pass filter which are sequentially arranged, the high-pass filter can suppress a natural potential and a magnetotelluric signal with the frequency lower than 0.1Hz, the first-stage low-pass filter can reduce the amplitude of a power frequency interference signal to the frequency lower than millivolt, the second-stage low-pass filter can suppress the power frequency interference signal, the third-stage low-pass filter can suppress a power supply noise signal, the digital filter can suppress out-of-band noise, a preamplifier is arranged between the high-pass filter and the first-stage low-pass filter, a first-stage main amplifier is arranged between the first-stage low-pass filter and the second-stage low-pass filter, a second-stage main amplifier is arranged between the second-stage low-pass filter and the third-stage low-pass filter, and a third-stage main amplifier is sequentially arranged between the third-stage low-pass filter and the digital filter.
3. The coal deep borehole while drilling data real-time wireless receiving system of claim 2, further comprising a receiving electrode for receiving electromagnetic signals.
4. A real-time wireless receiving system for while-drilling data of deep coal holes according to any one of claims 2-3, which is arranged inside or connected with an explosion-proof computer.
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| GB1341426A (en) * | 1970-06-24 | 1973-12-19 | Petroles Cie Francaise | System for transmitting information |
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