RU2480583C1 - Telemetric system of bottomhole parameters monitoring - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: telemetric system is proposed for monitoring of bottomhole parameters, using a pipe string for transfer of data with the help of an acoustic field, which comprises a surface module of reception and processing of a signal and a bottomhole module lowered into the pipe string, and the bottomhole module includes a unit of measurement of bottomhole parameters, a unit of control of a bottomhole module, a unit of an acoustic generator, a device of connection and disconnection with a pipe from the pipe string, an actuating mechanism, and also a power supply unit. The actuating mechanism is made as capable of providing a direct acoustic contact with the surface of the internal wall of the pipe by means of pressing of an element to it, which is made of a material with hardness exceeding the hardness of the pipe material, with introduction of the latter into the material of the pipe wall. The surface module of reception and signal processing is made with a function of registration of parameters of an information signal received in one or several different frequency ranges, and with a function of detection of working frequency ranges of the acoustic field by means of their selection inside frequency bands, where the level of natural and structural noise in the field of reception of the information signal on the surface is minimal relative to the level of the specified noise in other frequency bands.

EFFECT: improved efficiency of information transfer with the help of an acoustic field.

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Description

The invention relates to the field of production of liquid hydrocarbons and can be used to control well processes.

There are a number of “contact” methods for monitoring downhole processes that involve sampling in a well using various devices, for example, samplers, baits, core sampling devices, etc., delivering them to the surface and analyzing them using various methods - physical, chemical, geological and etc. (Intenberg S.S., Takhkilgov TD "Geophysical surveys in wells", M .: "Nedra", 1990).

The main disadvantage of this group of methods is that the measurements are carried out on the surface under conditions significantly different from the bottomhole, which dramatically affects the reliability and accuracy of the measurements.

A known method of monitoring downhole processes, implemented, for example, by a series of SAMT devices (Tomsk Scientific and Production and Implementation Society SIAM). The device is lowered into the well to the required depth, fixed there and takes measurements, followed by recording in the memory of the required parameters in offline mode for a certain time. Next, the device is removed, information is read, which is further analyzed (Operation manual for pressure gauges-thermometers in-depth ISM 3.211.005).

The main disadvantage of this control method is that it is impossible to analyze the dynamics of the measured parameters in real time.

A known method of monitoring downhole processes according to patent RU 2188319. The essence of the method is as follows. A geophysical instrument is lowered into the well. In parallel with the descent into the well of a geophysical instrument, a highly sensitive instrument is installed as recording equipment on the outside of the wellhead. The effects of downhole processes on a geophysical instrument and on a highly sensitive instrument are recorded. The readings of the highly sensitive instrument are calibrated and identified by the readings of the geophysical instrument, according to which nomograms and tables for the highly sensitive instrument are compiled. Then the geophysical instrument is removed from the well, and the well processes are monitored by a highly sensitive instrument.

The main disadvantage of the method of monitoring downhole processes according to patent RU 2188319 is the low reliability of the interpretation of recorded data. The highly sensitive device according to patent RU 2188319 captures elastic fields. Sources of elastic fields in a complex mechanical system, which is, for example, a production well, a significant amount. Many of them are uncontrollable. An ambiguous situation arises, for example, when the band of acoustic noise arising in fountain fittings under wind load coincides with the working band of a highly sensitive instrument in which a response to downhole processes is expected.

To transmit reliable data from the bottom to the surface in real time, a predictable and stationary data transmission channel is required.

Several options are possible: this is a cable channel, a channel that provides acoustic communication via downhole fluid (hydraulic channel), an electromagnetic channel, and an information transmission channel for well construction elements, for example, tubing pipes. Channel aggregation is also used.

Known downhole telemetry system designed to transmit downhole information to the surface via a wired communication channel (Kalinin A.G. et al. "Drilling of deviated wells", M .: "Nedra", 1990). This downhole telemetry system comprises an in-depth telemetry system unit, an in-depth measurement device, a ground control panel, a ground-based measurement device, and a communication cable. The presence of a communication cable inside the pipes has the following main disadvantages: high cost, problems in the reliability of connections and sealing, the need for special equipment for working with the cable, an increase in the time of tripping operations, and the limitation of the depth of use.

As well-known technical solutions for the transmission of information from the bottom using physical fields (elastic and electromagnetic), for example, in the field of well drilling, we can consider the well-known system for measuring downhole parameters during drilling (MWD) by Geoservis with an electromagnetic communication channel ("Technology of horizontal , directional and cluster drilling ”, Review of All-Russian Research Institute of Zarubezhgeologiya, 1991, issue 8 or the well-known telemetry system“ Slaughter ”(Report of VNIIGIS, 1993), etc.

A common drawback of telemetry systems with an electromagnetic communication channel is that in low-resistance sections, for example, in Western Siberia, the range of systems with an electromagnetic communication channel is limited, and for very high-resistance, for example, salt formations, the electromagnetic communication channel practically does not work, since the signal shielded.

Telemetry systems with a hydraulic communication channel are known, for example, according to SU 709807. Typically, such systems include devices that generate pressure pulses and ground-based recording equipment.

A common drawback of systems using a hydraulic communication channel is the non-stationary nature of this channel, which is fundamentally caused by a high level of ripple arising from the operation of the pumps, both drilling and operational. In addition, this channel does not work if the downhole fluid is a gaseous medium. This is due to the extremely low acoustic impedance of gaseous media and the high attenuation coefficient of the acoustic field in them.

Known telemetry systems for transmitting downhole parameters, where the channels, electromagnetic and hydraulic, are integrated, for example, according to patent RU 2194161. However, these systems are not free from the disadvantages inherent in these data channels separately.

A promising communication channel for telemetry systems is considered to be a channel for transmitting information on well design elements, for example, through tubing. A channel consisting of pipes rolled onto a thread (using couplings) is a complex dispersion-dissipative structure through which several types of waves can propagate (longitudinal, bending, and torsional vibrations) (Drumheller D. Acoustical properties of drill strings, J. Acoust Soc. Am., 1989, V. 85 (3); Drumheller D., Knudsen S. The propagation of sound waves in drill strings, J. Acoust. Soc. Am., V. 97 (4).

Technical solutions are known in which an operational (tubing) pipe is used to transfer data from the bottom to the surface. For example, technical solutions for patents US 4293936, US 4562559, US 5477505, US 7257050 and others. These technical solutions include a borehole unit containing an acoustic generator, a controller, a sensor system for measuring the required face parameters, a device for transmitting an acoustic signal to the production casing and ground-based equipment for signal reception and analysis.

In all known technical solutions, frequency ranges are used for signal transmission, which are theoretically defined as the transmission zones of a dispersion system consisting of screwed pipes of the same length. Couplings with which the column is screwed are also considered the same. Indeed, under this assumption, the tubing string transmits an acoustic signal in strictly defined frequency bands with a width of 100-200 Hz.

This method of determining the operating frequencies is a common drawback of technical solutions that use the transmission of an informative signal along the production string using the field of elastic vibrations leading to unreliable data transmission. The fact is that during the construction of production wells there is no requirement to observe the equidistance of the location of the couplings in the production casing. For example, production cores in the Vyngapur gas field contain tubing pipes with lengths of 7 to 10 meters. Such a spread in the length of the tubing pipes leads to the fact that the column ceases to be a system with strong dispersion and becomes a propagation channel of the acoustic field with strong attenuation. It is necessary to add to this that in reality most often there are contacts of the couplings with the casing, which also, in the general case, reduces dispersion and increases the attenuation of the acoustic field propagating along the tubing string. A sharp difference between the real situation and the theoretical one leads to the fact that in the production casing it becomes possible to propagate a pulse signal. To prove this fact, a series of field experiments was performed. An acoustic impulse was excited at the fountain fittings of an operating gas well, then an acoustic signal was received at the same fountain fittings reflected from a section of the tubing string located at the bottom. The incoming pulses were identified by the arrival time, since the length of the tubing string is known, and the longitudinal and torsional vibration modes propagating along the tubing string with the least attenuation are also known.

The following are the results of one of the experiments conducted at the Komsomolskoye gas field (Gubkinsky), the 1st well of the 19th bush of the Northern Dome (No. 119.1). The well is equipped with fountain fittings 9 ^5/8 × 6 ^5/8 × 4 ^1/2 , production casing is screwed from tubing ⌀114 × ⌀100 and couplings with external ⌀132 (GOST 633-80), pipe lengths are in the range of 8- 10 m, the total length of the tubing string L ~ 900 m. An acoustic pulse signal was excited in the “pear” region of the tubing string suspension using an “impact hammer” type 8208 from Bruehl & Kjерr, and a signal was received in the same area using KD piezo-accelerometers -23. The signal was excited broadband with a central frequency of the order of 1.5 kHz. Figures 1 and 2 show the current spectra of acoustic signals received by the sensors.

Figure 1 shows the current spectrum of the signal upon excitation of an acoustic field of predominantly vertical polarization upon receipt of a signal of the same polarization. The signal is clearly fixed with the arrival time T ₁ = 2L / C _I , where L is the length of the tubing pipe, C _I is the velocity of longitudinal vibrations in the pipe. The measured time T ₁ is 0.36 s ± 0.01 s.

Figure 2 presents the current spectrum of the signal upon excitation of the acoustic field of predominantly tangential polarization upon receipt of a signal of the same polarization.

Here, the signal is fixed with the arrival time T ₂ = 2L / C _t , where L is the length of the tubing pipe, C _t is the speed of transverse vibrations in the pipe. The measured time T ₂ is 0.52 ± 0.01 s.

Obviously, the energy of the signals is fairly evenly distributed over the spectrum in the region of 100-3000 Hz, which indicates a weak dispersion during the propagation of the acoustic field in a real production string, screwed from tubing with couplings. Also, the experimental results showed that the actual production casing is a medium with a very strong attenuation of the acoustic field. According to estimates of the obtained experimental data, the torsional and longitudinal modes, under conditions of uneven arrangement of couplings, have approximately the same attenuation coefficient, in the region of 45 dB / km.

Thus, in the well-known technical solutions for the creation of telemetry systems using an acoustic communication channel over the production casing, the choice of the frequency band leads to unreliable transmission of information. The working frequency bands selected from theoretical concepts may coincide with the intense noise bands at the points of reception of the informative signal located on the structural elements of the well that are on the surface (fountain reinforcement). A production well is a complex structure with a significant amount of mechanical resonances that can be excited by various sources: fluid moving in the well, climatic phenomena on the surface, downhole processes, etc. Moreover, the noise “portrait” of a well is unique and cannot be predicted in advance.

Studies of acoustic noise at various points of the fountain reinforcement have shown that intrinsic acoustic noise has a stationary spectrum. Various wells with different fountain fittings were investigated. Figure 3 and 4 as an example shows typical spectra of the intrinsic noise of wells, measured on their fountain fittings. Figure 3 presents the results for well No. 119.1 of the Komsomol gas field equipped with fountain fittings 9 ^5/8 × 6 ^5/8 × 4 ^1/2 (Hungarian production). The spectra of acoustic noise received by the vertical sensors — curve 1 and tangential — curve 2 polarizations are shown. Figure 4 - along well No. 198 of the Vyngapur gas field, which is equipped with AFK6 fountain fittings - 100 × 120 HL (Azerbaijani production). Also shown are the spectra of acoustic noise received by the vertical sensors - curve 1 and tangential - curve 2 polarizations.

Noises were recorded on fountain fittings at points as close as possible to the places of suspension of tubing pipes. The shape of the noise spectrum (frequency distribution of noise) is practically independent of flow rate, i.e. the speed of gas in the pipe, from the wind situation and time of year. Thus, it is obvious that for any well, it is possible to choose a frequency range with a minimum level of intrinsic noise.

The present invention is aimed at overcoming the disadvantages inherent in the known technical solutions, and the creation of a new telemetry system using an acoustic communication channel for the structural elements of the well, in particular for the production string.

The technical result achieved in this case is to increase the reliability and efficiency of information transfer using the acoustic field through the production casing and to significantly increase the reliability of the received information in real time. The present invention also achieves increased reliability of the entire telemetry system.

For the prototype adopted a technical solution according to the patent US 7257050, G01V 1/00, G01V 1/02, G01V 1/16, G01V 1/40, publ. 06/09/2005, which claims a system for transmitting acoustic signals through a production casing from the bottom to a receiver located on the surface, the system comprising: an acoustic wave generator, a coupling device mechanically coupled to an acoustic wave generator, and the coupling device is configured to connection and disconnection with the pipe, in addition, the interface device sets the transmission path of the acoustic field from the acoustic wave generator to the pipe when paired with the pipe, and the signal controller in associated with an acoustic wave generator. The transmission of the acoustic signal occurs in the longitudinal (compression) mode of oscillation in the range of minimizing losses associated with the location of the couplings.

Significant disadvantages of the prototype are the following:

- firstly, the transmission range of the acoustic signal is selected on the basis of the assumption that there are areas of "transparency" when the acoustic signal passes through the acoustic channel, which consists of pipes screwed with tubing couplings, which in reality, at least for gas fields Russia does not exist. This fact leads to unreliable transmission of information, since the informative transmission range can fall into the band of intense acoustic noise at the receiving point.

- secondly, the combination in one device of the functions of fixing the downhole part of the system at the bottom and the function of creating acoustic contact between the acoustic wave generator and the inner surface of the pipe leads to unreliability of the acoustic contact. Any vibrations arising in the production casing may displace the contact point, while the boundary conditions change and the efficiency of the transfer of acoustic energy from the acoustic generator into the pipe changes. In addition, this arrangement of the downhole part of the system leads to additional attenuation of the acoustic field when it passes through the moving parts of the interface device, which also affects the efficiency and reliability of information transfer using the acoustic field.

The specified technical result in the present invention is achieved by the fact that when deploying a telemetry system containing ground and bottom parts, the well noise is measured at the points of further placement of the sensitive elements of the ground data collection system, the operating frequency range of the telemetry system is selected and put into the work program bottomhole part. The downhole part contains a measuring unit equipped with downhole sensors that need to be measured; an electronic unit comprising a programmable controller and electronic parts of an acoustic generator; a block including the executive parts of the acoustic generator and a mechanism for creating acoustic contact of the executive parts of the acoustic generator and the inner surface of the pipe; an electric power supply unit and a mechanical fixation unit for the bottom hole inside the production casing. Moreover, the acoustic contact between the Executive part of the acoustic generator and the inner surface of the pipe is created through a mechanical element having a hardness greater than the material from which the pipe is made. In this case, the mechanism of creating an acoustic contact provides the clamping of this mechanical element to the inner wall of the pipe with constant force, which ensures the surface penetration of the element into the inner wall of the pipe.

The invention is illustrated in the drawings, where:

figure 1 presents the current spectrum of the signal when exciting an acoustic field of predominantly vertical polarization when receiving a signal of the same polarization, data from experiments conducted at the Komsomol gas field (Gubkinsky), well No. 119.1 of the Komsomol gas field;

figure 2 presents the current spectrum of the signal when exciting an acoustic field of predominantly tangential polarization when receiving a signal of the same polarization, data from experiments conducted in the Komsomolskoye gas field (Gubkinsky), well No. 119.1 of the Komsomolskoye gas field;

figure 3. the spectra of the intrinsic noise of the wells are presented, measured at their fountain fittings, the results for well No. 119.1 of the Komsomol gas field, the spectra of acoustic noise received by the vertical sensors — curve 1 and tangential — curve 2 polarizations;

figure 4 presents the spectra of the intrinsic noise of the wells, measured on their fountain fittings, the results for well No. 198 of the Vyngapur gas field, shows the spectra of acoustic noise received by the vertical sensors - curve 1 and tangential - curve 2 polarizations;

figure 5 shows the layout of the nodes of the control system downhole parameters;

Fig.6 shows a preliminary stage of deployment of a telemetry system;

Fig.7 shows the General layout of the bottom of the control system;

Fig.8 shows a diagram of the creation of acoustic contact between the actuator of the acoustic generator and the inner wall of the pipe;

Fig.9 is one of the possible schemes for implementing the algorithm for extracting information from the input signal.

According to the present invention, a construction of a telemetry face control system is considered that uses a pipe string to transmit data using an acoustic field.

To ensure the reliability and reliability of data transmission over the pipe string, this system, in a block diagram form, consists of a ground-based signal receiving and processing module and a downhole module lowered into the pipe string, which includes a downhole parameter measurement unit, a downhole module control unit, an acoustic generator unit, a device for connecting and disconnecting a pipe from a pipe string that implements the function of fixing the downhole module inside the pipe string, an actuator that implements the function of creating an acus static contact of the actuator with the pipe, as well as an autonomous power supply unit (a unit functioning autonomously without supplying energy from outside).

In this case, the actuator is configured to provide direct acoustic contact with the surface of the pipe’s inner wall by clamping to it an element made of a material with a hardness exceeding the hardness of the pipe material and incorporating the latter into the pipe wall material (acoustic contact is created by surface penetration into the pipe’s inner surface an element having a strength greater than the strength of the pipe material).

The ground-based module for receiving and processing a signal is made with the function of registering the parameters of the information signal received in one or several frequency ranges that are different from each other, and with the function of determining the working frequency ranges of the acoustic field by selecting them inside the frequency bands in which the level of natural and structural noise in the field of reception of an informative signal on the surface is minimal with respect to the level of the specified noise in other frequency bands.

In this system, two modes of oscillations propagating along a pipe string, a longitudinal mode and a torsional mode are used to transmit an informative signal. At the same time, the length of the informative acoustic package is selected based on the condition of not superimposing on each other at the point of reception of signals propagating along the pipe string with speeds of longitudinal and torsional modes. In the downhole module, the function of long-term fixation of the downhole module inside the pipe string and the function of creating acoustic contact of the actuator of the acoustic generator with the inner surface of the pipe are structurally disconnected.

Below is an example of the execution of a telemetry system with reference to Fig.5-9.

The telemetry system (Fig. 5) consists of a downhole part 1 and a ground part 2. The connection between the downhole and ground parts is carried out using an acoustic field propagating through a string of 3 tubing pipes. The tubing pipes in the string are screwed using couplings - 4. The bottomhole part 1 is attached inside the tubing string to the internal groove of the coupling. The ground part 2 is mounted on the fountain arm 5. The bottomhole part 1 has acoustic contact with the inner wall 6 of the pipe NK and stand-alone clamp 7 to create an acoustic contact. The ground part 2 is securely attached to the elements of the ground equipment of the well, the sensitive elements of the ground part (not shown in Fig. 5) are mounted in places closest to the place of attachment of the tubing string. As sensitive elements can be used one or multicomponent vibration sensors, for example, piezoelectric accelerometers. Terrestrial part 2, in addition to sensitive elements, can contain input circuits in the form of filters and an amplifier, ADC, buffer RAM, controller, autonomous or external power supply, data channel, wired or wireless (the elements of the ground part are not shown in Fig. 3 and can have a standard execution).

Before descending into the tubing string 3 (FIG. 6), the bottomhole part is programmed to transmit information in certain frequency bands. Why explore their own noise environment at the head of the well (fountain fittings). Studies are carried out using acoustic sensors 8, for example, piezoelectric accelerometers. Studies can be conducted for various polarizations of the acoustic field. The signals obtained using sensors 8 are analyzed using an analyzer 9, then using the programmer 10, the electronic unit 11 of the bottomhole part 1 is programmed.

The bottomhole part 1 of the telemetry system consists of the following blocks: clamping acoustic unit 12, electronic unit 11 (Fig.7). The electronic unit contains a controller, a bottomhole control circuit and radio cascades of an acoustic generator. Block 13 contains downhole sensors that you want to measure. The downhole part also contains a power supply unit 14 (an autonomous power supply unit) and a block 15 for mechanically fixing the downhole part in the tubing string. Between blocks 12 and 14, a flexibility element 16 may be included to balance the downhole part 1 when making an acoustic contact. In this case, the element of flexibility may be a bellows. The flexibility element may be included in the downhole part 1 between blocks 14 and 15. In this case, the flexibility element may be a hinge system.

Block 12 is pressed against the inner wall of the pipe string 3 by an autonomous mechanism 17, for example, with an electric drive (Fig. 8). To create direct acoustic contact, a special element 18 is used, made of a material with a hardness exceeding the hardness of the pipe material. When pressed, the element 18 is embedded in the pipe 3, while creating a reliable acoustic contact. Element 18 is connected to an acoustic transducer 19, providing acoustic contact. The Converter 19 can be made in the form of a piezoceramic stack with plates 20 of the desired shape.

The telemetry system operates as follows. Before lowering the bottomhole part 1 inside the tubing string 3, measurements are made of their own noise environment in places on the fountain fittings, where further informative signal is supposed to be removed. To obtain complete information, the vibration field of various polarizations is measured using one or multicomponent sensors 8. The information is analyzed using an analyzer 9, the frequency range with the lowest level of acoustic noise is selected. The operating range is determined based on the transmission algorithm selected for transmitting the informative signal. For example, in one of the options it is supposed to take information about three downhole parameters (pressure, temperature and angle). Why is the information converted to digital form, then the obtained 8 tetrads (nibbles) of information are supplemented with the information computed using the Reed-Solomon algorithm (Bleikhut R. “Theory and Practice of Error Control Codes”, Moscow: Mir, 1986) with 6 control notebooks , allowing to correct up to three errors when receiving such information. Then, each of the obtained 14 notebooks is associated with the values of two frequencies of a sinusoidal signal out of seven, the transmission of which is provided through an acoustic communication channel. In one of the options, the difference between adjacent frequencies is selected at 80 Hz, so it is necessary to choose a frequency range of 480 Hz, in which the lowest level of intrinsic noise is observed at the place of reception of the informative signal by the ground part 2 of the telemetry system.

After selecting a specific frequency range, using the programmer 10 program the electronic unit 11 of the downhole part 1, determining the specific operating frequency. In addition, the following parameters are programmable in the electronic unit 11: time T ₁ is the response time of the stand-alone clamp of the unit 12 to create an acoustic contact of the unit 12 with the wall 3 of the tubing 3; time T ₂ - time to start measuring the parameters of the face by block 13; time T ₃ - start time of data transmission, i.e. the start time of the acoustic generator transmitting the information signal; time T ₄ - time to complete the work on measuring parameters and transmitting data along the tubing string; time T ₅ is the response time of the stand-alone clamp of the block 12 to disconnect the block 12 with the pipe and transfer the bottomhole part to the transport position. The auxiliary time parameters associated with the time of averaging data, the frequency of their transmission, long transmission, etc. are also programmed.

The programming of the electronic unit 11 also includes the synchronization of the real-time clock of the controller of the block 11 with the real-time clock of the controller of the ground block 2.

After programming and synchronization, the bottomhole part 1 of the telemetry system is assembled. As a mechanical fixation unit, the UPGP2A-100 device (a suspension device for deep devices in a tubing string with an external diameter of 114 mm), developed by CJSC TsGI INFORMPLAST, can be used. The bottomhole part is placed in a lubricator and lowered to the required depth using standard geophysical means, for example, a winch equipped with a geophysical cable. Depth is controlled by a winch counter. When the required depth is reached, which is determined by the position of a pre-selected coupling located in the vicinity of the current face, manipulations are performed according to the operating instructions of the UPGP device and the bottom part is posted in the tubing string. The time of all manipulations should be less than the time T ₁ .

At time T _{1, the} controller of the electronic unit 11 issues a command to trigger the clamping mechanism of block 12. The clamping mechanism can be made in the form of a clamping foot, driven by a DC motor with a gearbox. The clamping force necessary for the surface introduction of the element 18 into the tubing wall is controlled, for example, by the current consumption of the motor. When the current rises to a certain, pre-calibrated value, the motor is turned off and braked in the stopped position using, for example, an electromagnetic clutch.

At time T ₂ , which is obviously longer than T ₁ , taking into account the time interval required to create an acoustic contact, unit 13, upon the command of the controller of unit 11, starts measuring the face parameters. After a period of time necessary for measurements, averaging of data and their processing, at time T _{3, the} controller of block 11 generates a code containing information about the measured parameters. This code, using an acoustic generator located in block 11 and an acoustic engine located in block 12, is transmitted as an informative acoustic signal to a communication channel, which is a tubing string.

The length of the acoustic package is selected based on the condition of non-overlapping signals received by the sensitive elements of the ground unit 2, propagating through the pipe string with different speeds. For example, with the speed of longitudinal and torsional vibrations.

Reception is carried out by the sensitive elements of block 2 in time windows synchronized with the time T ₃ , but with a delay necessary to cover an acoustic signal with a distance equal to the length of the tubing string.

For one of the options for transmitting information at seven fixed frequencies with 14 information tetrads, a block diagram of an algorithm for extracting information from an input signal is shown in Fig. 9.

To isolate the signals at the operating frequencies of the transmission over the communication channel, resonators implemented using the Herzel algorithm are used, which reduces the amount of computation as compared to calculating the spectrum or filtering with bandpass filters, in addition, the output of such resonators is not the signal itself, but its envelope.

At the beginning of the operation session of the ground unit 2, the noise level of the communication channel, i.e. the ratio of the sums of signals at operating frequencies to the overall level of the input signal is found in the absence of a useful signal. The obtained value with a certain coefficient is used as a threshold level for determining the presence of a useful signal. After the threshold value is determined, the ground unit 2 awaits the appearance of a useful signal that causes the start of a signal that triggers a timer having a time interval equal to the duration of the two-frequency transmissions emitted by the transmitting node. The values of the output signals of the resonators are fixed by the timer signal, at this moment the output signals of the resonators, at the frequencies of which there is a useful signal, reaches a maximum value. Then, the output signals of the resonators are sorted by amplitude and three of them having the maximum value are selected from them. Then, signals having a second and third value from the maximum are compared with each other, and if there is an excess of one over the other by more than 1.8 times, a decision is made on the clear separation of signals of two frequencies and the value of the tetrad of the input signal is restored, otherwise a decision is made about missing a signal. After the entire input signal is received, the received information is checked for errors using the Reed-Solomon algorithm and, if necessary, the restoration of distorted information. If during the reception process there were cases of missing the input signal, then all possible states of the missed signal are sorted out sequentially, and the information is analyzed by the Reed-Solomon algorithm until the latter indicates the absence of an error (or restores an erroneous character).

Further, information about the measured parameters of the face is displayed in the ground block 2 or transmitted via any (wired or wireless) communication channel to the point of further processing and analysis.

The times T ₄ and T ₅ are associated with a given time spent by the bottomhole part 1 of the telemetry system on the bottom. Based on this and the required frequency of data transmission from the bottom to the surface, the parameters of the power supply unit 14 of the bottom section are calculated. The power supply can have any design. This can be a generator that works by converting the energy of a gas stream into electricity, or a generator based on a direct piezoelectric effect that converts the energy of a field of natural noise and vibrations at the bottom to electricity, etc.

In one embodiment, the power supply unit contains lithium batteries LO 39 SHX (SAFT, 3B, 11 Ah) in the amount necessary (8-10 pieces) so that their total capacity allows all manipulations to hold the unit 12 against the tube and further undocking at time T ₅ and to ensure data transmission with a frequency of three times a day for 3 years.

At the time T ₅ , which immediately follows the time T ₄ - the time of the end of the measurement and data transfer, the controller of block 9 issues a command to undock the block 8 from the tubing and the bottomhole is transferred to the transport position. The bottomhole part is extracted using a standard catcher, which is included in the unit of the UPGP device. The catcher is lowered on a geophysical cable using standard geophysical means.

In one embodiment of the invention, the beginning of the measurement of the parameters of the face and their subsequent transmission to the surface, as well as the termination of the measurement and the translation of the face to the transport position, is carried out by command from block 2. Communication can also be carried out using an acoustic field, for example, pulse sequences kind of.

The telemetry system described above will dramatically increase the reliability of real-time data transmission from the bottom of production wells, which will allow for continuous and reliable monitoring of well processes in order to optimize and intensify the production of liquid hydrocarbons. The application of the described telemetric systems for monitoring downhole parameters in real time at the field as a whole will allow creating a system for monitoring the field and long-term production planning.

Claims (1)

A telemetric control system for bottomhole parameters, using a pipe string for transmitting data using an acoustic field, consisting of a ground-based signal receiving and processing module and a downhole module that is lowered into the pipe string, which includes a block for measuring downhole parameters, a control unit for the bottomhole module, and an acoustic generator unit , a device for connecting and disconnecting a pipe from a pipe string, realizing the function of fixing the downhole module inside the pipe string, an actuator that implements the function acoustic contact of the actuator with the pipe, as well as a power supply unit, characterized in that to ensure the reliability and reliability of data transmission along the pipe string, the actuator is configured to provide direct acoustic contact with the surface of the inner wall of the pipe by pressing it made of material with hardness exceeding the hardness of the pipe material, the element with the introduction of the latter into the pipe wall material, the power module of the downhole module is autonomous, and The main signal receiving and processing module is configured to register information signal parameters in one or several frequency ranges that are different from each other and to determine the working frequencies of the acoustic field by selecting them within frequency ranges in which the level of natural and structural noise in the field of receiving an informative signal on the surface is minimal in relation to the level of the indicated noise in other frequency ranges.

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