Electromagnetic wave signal-based coal-bed gas well drainage and mining parameter wireless acquisition system and method

Abstract

The invention discloses a coal-bed gas well drainage and mining parameter wireless acquisition system and method based on electromagnetic wave signals. The system comprises a coal-bed gas well electromagnetic wave transmission subsystem and a coal-bed gas well mouth electromagnetic wave receiving subsystem. The coal-bed gas well electromagnetic wave transmission subsystem comprises a pressure and temperature parameter measurement assembly, a communication interface, a well signal processor, an electromagnetic wave emitter, a power supply I, a rechargeable battery and a mining-following hydraulic generator; the data acquisition module is used for realizing acquisition and wireless transmission of pressure and temperature parameters; the coal bed gas wellhead electromagnetic wave receiving subsystem comprises a power supply II, a wellhead antenna, a wellhead electromagnetic wave receiver, a wellhead signal processor, a wellhead industrial personal computer and a display; and the signal processing module is used for carrying out noise reduction, filtering, demodulation and modulation processing on the electromagnetic wave signal to obtain bottom hole flowing pressure and bottom hole temperature data. Continuous and long-time collection of coal-bed gas well drainage and mining data can be achieved, operation is safe and reliable, and important guarantee significance is achieved for increasing the gas production rate of coal-bed gas.

Description

Technical Field

[0001] The present invention belongs to the technical field of coalbed methane development, and relates to a wireless acquisition system and method for coalbed methane well drainage parameters based on electromagnetic wave signals. Background Art

[0002] Coalbed methane mainly exists in the form of adsorbed state on the inner surfaces of pores and fractures of coal, and it is necessary to drain water to reduce pressure to achieve the production of coalbed methane. In order to formulate a reasonable drainage working system and achieve fine and continuous scientific drainage of coalbed methane, it is necessary to collect parameters such as bottom-hole flowing pressure, bottom-hole temperature, casing pressure, water production, and gas production. Among them, the casing pressure, water production, and gas production data are collected at the wellhead, and the bottom-hole flowing pressure and bottom-hole temperature parameters need to be collected in the well. Currently, there are two ways to obtain the bottom-hole flowing pressure and bottom-hole temperature parameters. One is the liquid level interpretation method, that is, the position of the bottom-hole dynamic liquid level is obtained through on-site testing with a liquid level tester, and the bottom-hole flowing pressure can be calculated through the position of the bottom-hole dynamic liquid level, but the bottom-hole temperature cannot be obtained. There are 3 common methods for interpreting the dynamic liquid level, namely the collar method, the phonetic method, and the acoustic velocity method. The other is a data acquisition system with wired transmission, that is, a pressure gauge is installed in the well and transmitted to the ground through a cable, and the bottom-hole flowing pressure and bottom-hole temperature are directly read out.

[0003] The above methods have limitations. The liquid level interpretation method has problems such as inaccurate interpretation of the bottom-hole flowing pressure and time-consuming and laborious continuous testing; the data acquisition system with wired transmission is restricted by the size of the drainage string, the inner diameter of the casing, and the complex wellbore trajectory of directional wells and horizontal wells. The data acquisition system is prone to problems such as cable wear and water leakage at the connection between the cable and the pressure gauge, resulting in a short normal service life and being unable to meet the requirements of "fine and continuous" scientific drainage of coalbed methane. In addition, for small-diameter wells, there are also problems such as the inability to lower the data acquisition system with wired transmission. Summary of the Invention

[0004] Aiming at the deficiencies existing in the prior art, the purpose of the present invention is to provide a wireless acquisition system and method for coalbed methane well drainage parameters based on electromagnetic wave signals, to solve the problems such as inaccurate interpretation of the bottom-hole flowing pressure faced by the liquid level interpretation method for coalbed methane well drainage parameter acquisition, time-consuming and laborious continuous testing, short normal service life of the data acquisition system with wired transmission, and inability to be used in some wells, and to achieve the purpose of "continuous and long-term" acquisition of coalbed methane well drainage data, which has important guarantee significance for increasing the gas production of coalbed methane.

[0005] In order to solve the above technical problems, the present invention is implemented by adopting the following technical solutions:

[0006] A wireless acquisition system for coalbed methane well drainage parameters based on electromagnetic wave signals includes an electromagnetic wave transmission subsystem in the coalbed methane well and an electromagnetic wave receiving subsystem at the coalbed methane wellhead;

[0007] The electromagnetic wave transmission subsystem in the coalbed methane well includes a pressure and temperature parameter measurement assembly, a communication interface, a downhole signal processor, an electromagnetic wave transmitter, Power Supply I, a rechargeable battery, and a fluid-driven generator driven by production fluid; it is used to collect and wirelessly transmit pressure and temperature parameters.

[0008] The electromagnetic wave receiving subsystem at the coalbed methane wellhead includes Power Supply II, a wellhead antenna, a wellhead electromagnetic wave receiver, a wellhead signal processor, a wellhead industrial control computer, and a display; it is used to perform noise reduction, filtering, demodulation, and modulation processing on the electromagnetic wave signal to obtain bottomhole flowing pressure and bottomhole temperature data.

[0009] The present invention further includes the following technical features:

[0010] Specifically, the fluid-driven generator driven by production fluid is connected to the rechargeable battery, the rechargeable battery is connected to the pressure and temperature parameter measurement assembly, the communication interface, the downhole signal processor, and the electromagnetic wave transmitter, and the downhole signal processor is connected to the electromagnetic wave transmitter and the communication interface.

[0011] Specifically, the pressure and temperature parameter measurement assembly includes a pressure sensor, a temperature sensor, a first signal conditioning circuit, a second signal conditioning circuit, a multi-channel A / D converter, and a microprocessor, which is used to obtain the bottomhole flowing pressure and bottomhole temperature at the location of the parameter measurement assembly in the coalbed methane well.

[0012] The pressure sensor and the temperature sensor are respectively connected to the multi-channel A / D converter through the first signal conditioning circuit and the second signal conditioning circuit, and the multi-channel A / D converter is connected to the microprocessor.

[0013] Specifically, the pressure sensor and the temperature sensor obtain original analog voltage signals, which are amplified and filtered by the first signal conditioning circuit and the second signal conditioning circuit and then sent to the multi-channel A / D converter to be converted into digital voltage signals, and then the digital voltage signals are sent to the microprocessor.

[0014] Specifically, Power Supply I can supply power to the pressure sensor, temperature sensor, first signal conditioning circuit, second signal conditioning circuit, multi-channel A / D converter, and microprocessor of the pressure and temperature parameter measurement assembly.

[0015] Specifically, the communication interface can realize the communication connection between the downhole signal processor and the pressure and temperature parameter measurement assembly;

[0016] The downhole signal processor can read the data collected by the pressure and temperature parameter measurement assembly transmitted by the communication interface, select the modulation method and center frequency, and then transmit it to the electromagnetic wave transmitter for processing.

[0017] Specifically, the electromagnetic wave transmitter includes an electromagnetic wave transceiver module and an electromagnetic wave transmitting antenna. The electromagnetic wave transceiver module can convert the pressure and temperature information measured by the pressure and temperature parameter measurement assembly into a low-frequency electromagnetic wave signal through modulation, and after voltage and power amplification, it is transmitted into the extraction string and the formation through the electromagnetic wave transmitting antenna. The electromagnetic wave transmitting antenna uses a dipole antenna.

[0018] Specifically, the Power Supply II is respectively connected to the wellhead antenna, the wellhead electromagnetic wave processor, the wellhead signal processor, the wellhead industrial control computer and the display. The wellhead electromagnetic wave processor, the industrial control computer and the display are all connected to the wellhead signal processor. Both ends of the wellhead antenna are respectively connected to the wellhead electromagnetic wave processor and the electromagnetic wave transmitter.

[0019] Specifically, the wellhead antenna can receive the electromagnetic waves transmitted from the wellbore. The wellhead electromagnetic wave processor converts the transmitted electromagnetic wave signal into an electrical signal, and after amplification, noise reduction and filtering processing, it performs analog-to-digital conversion. The digital signal after analog-to-digital conversion is connected to the wellhead signal processor for processing and analysis. The industrial control computer and the display module are used for data processing, storage and display.

[0020] A wireless acquisition method for coalbed methane well drainage parameters based on electromagnetic wave signals, which is realized based on the wireless acquisition system for coalbed methane well drainage parameters based on electromagnetic wave signals described above; includes the following steps:

[0021] Step 1: Assemble the well drainage string containing the electromagnetic wave transmission subsystem in the coalbed methane well and lower it into the well according to the drainage design.

[0022] Step 2: The rechargeable battery powers other electrical systems of the electromagnetic wave transmission subsystem in the coalbed methane well. The electromagnetic wave transmission subsystem in the well collects the bottom-hole flowing pressure and bottom-hole temperature data, performs modulation of the low-frequency electromagnetic wave signal, and transmits the low-frequency electromagnetic wave transmission signal for acquisition. The coalbed methane wellhead electromagnetic wave receiving subsystem receives the low-frequency electromagnetic wave, and performs noise reduction, filtering, demodulation and modulation processing on the low-frequency electromagnetic wave signal to obtain the bottom-hole flowing pressure and bottom-hole temperature data.

[0023] Step 3: Combine the bottom-hole flowing pressure and the bottom-hole temperature drainage data, formulate a drainage system, and carry out drainage and pressure reduction.

[0024] Step 4: During drainage, the drainage water flow of the drainage string drives the downhole hydraulic generator to generate electricity, realizing the charging of the rechargeable battery.

[0025] Step 5: When the water production is less than the water volume requirement of the downhole hydraulic generator, it is solved by increasing the drainage volume and injecting the drainage water back into the wellhead.

[0026] Compared with the prior art, the present invention has the following technical effects:

[0027] The present invention combines electromagnetic wave transmission technology, digital signal processing technology, data acquisition technology and drainage technology to achieve wireless transmission and acquisition of drainage parameters, and solves the problems faced by the current liquid level interpretation method for collecting drainage parameters in coalbed methane wells, such as inaccurate bottom hole flowing pressure interpretation, time-consuming and laborious continuous testing, short normal service life of wired transmission data acquisition systems, and inapplicability in some wells.

[0028] The present invention uses a fluid-driven generator with coalbed methane production to power the electromagnetic wave transmission subsystem in coalbed methane wells, solves the continuous power supply of rechargeable batteries in the wells, and realizes long-term continuous drainage of coalbed methane wells.

[0029] The wireless acquisition system for coalbed methane well drainage parameters based on electromagnetic wave signals of the present invention is safe and reliable in operation, thus solving the increased costs brought by well workover, being beneficial to improving the gas production effect of coalbed methane wells, and having significant comprehensive economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a system block diagram of the wireless acquisition system for coalbed methane well drainage parameters based on electromagnetic wave signals provided by an embodiment of the present invention.

[0031] Figure 2 It is a schematic flow diagram of the wireless acquisition method for coalbed methane well drainage parameters based on electromagnetic wave signals provided by an embodiment of the present invention.

[0032] The meanings of the various reference numerals in the figure are as follows:

[0033] 1. Electromagnetic wave transmission subsystem in coalbed methane well, 2. Electromagnetic wave receiving subsystem at coalbed methane wellhead;

[0034] 101. Fluid-driven generator with coalbed methane production, 102. Rechargeable battery, 103. Power supply I, 104. Pressure and temperature parameter measurement assembly, 105. Communication interface, 106. Signal processor in the well, 107. Electromagnetic wave transmitter;

[0035] 201. Power supply II, 202. Wellhead antenna, 203. Wellhead electromagnetic wave receiver, 204. Wellhead signal processor, 205. Wellhead industrial control computer and display;

[0036] 10401. Pressure sensor, 10402. Temperature sensor, 10403. First signal conditioning circuit, 10404. Second signal conditioning circuit, 10405. Multichannel A / D converter, 10406. Microprocessor;

[0037] 10701. Electromagnetic wave transceiver module, 10702. Electromagnetic wave transmitting antenna 10702. DETAILED DESCRIPTION OF THE INVENTION

[0038] Specific embodiments of the present invention are given below. It should be noted that the present invention is not limited to the following specific embodiments, and any equivalent transformation based on the technical solution of this application falls within the protection scope of the present invention.

[0039] Embodiment 1:

[0040] The wireless acquisition system for coalbed methane well drainage parameters based on electromagnetic wave signals realizes the modulation of low-frequency electromagnetic wave signals for pressure and temperature data, and the acquisition of downhole low-frequency electromagnetic wave transmission signals. Using digital signal processing technologies such as digital filtering and correlation analysis, the signals are processed for noise reduction, filtering, demodulation, modulation, etc. at the wellhead to obtain pressure and temperature data, providing decision-making data for drainage engineering personnel. In the actual use of the wireless acquisition system for coalbed methane well drainage parameters based on electromagnetic wave signals, it is hoped that under the condition of ensuring accurate signal transmission, the depth of the drainage well used is large and the data transmission rate is as fast as possible. In principle, the data transmission rate is positively correlated with the signal carrier frequency. However, the higher the electromagnetic wave frequency, the greater the attenuation of the signal by the formation during formation propagation, and the attenuation increases with the increase of depth. Therefore, the low-frequency propagation distance is relatively farther. Therefore, the wireless acquisition system for coalbed methane well drainage parameters based on electromagnetic wave signals needs to be able to make corresponding adjustments to the system design according to different transmission depths to achieve the optimal choice.

[0041] Based on this, this embodiment provides a wireless acquisition system for coalbed methane well drainage parameters based on electromagnetic wave signals, as Figure 1 shown, which includes an electromagnetic wave transmission subsystem 1 in the coalbed methane well and an electromagnetic wave receiving subsystem 2 at the coalbed methane wellhead.

[0042] The electromagnetic wave transmission subsystem 1 in the coalbed methane well includes a pressure and temperature parameter measurement assembly 104, a communication interface 105, a downhole signal processor 106, an electromagnetic wave transmitter 107, a power supply I 103, a rechargeable battery 102, and a hydraulic generator 101 for production; it is used to realize the acquisition and wireless transmission of pressure and temperature parameters.

[0043] The electromagnetic wave receiving subsystem 2 at the coalbed methane wellhead includes a power supply II 201, a wellhead antenna 202, a wellhead electromagnetic wave receiver 203, a wellhead signal processor 204, and a wellhead industrial control computer and display 205; it is used to perform processing such as noise reduction, filtering, demodulation, and modulation on the electromagnetic wave signals to obtain bottom-hole flowing pressure and bottom-hole temperature data.

[0044] The hydraulic generator 101 for production is connected to the rechargeable battery 102, and the rechargeable battery 102 is connected to the pressure and temperature parameter measurement assembly 104, the communication interface 105, the downhole signal processor 106, and the electromagnetic wave transmitter 107. The downhole signal processor 106 is connected to the electromagnetic wave transmitter 107 and the communication interface 105;

[0045] The pressure and temperature parameter measurement assembly 104 includes a pressure sensor 10401, a temperature sensor 10402, a first signal conditioning circuit 10403, a second signal conditioning circuit 10404, a multi-channel A / D converter 10405, and a microprocessor 10406, and is used to obtain the bottom-hole flowing pressure and bottom-hole temperature at the location where the parameter measurement assembly in the coalbed methane well is located.

[0046] The pressure sensor 10401 and the temperature sensor 10402 are respectively connected to the multi-channel A / D converter 10405 through the first signal conditioning circuit 10403 and the second signal conditioning circuit 10404, and the multi-channel A / D converter 10405 is connected to the microprocessor 10406.

[0047] The pressure sensor 10401 and the temperature sensor 10402 obtain the original analog voltage signals. The first signal conditioning circuit 10403 and the second signal conditioning circuit 10404 amplify and filter the signals and then send them to the multi-channel A / D converter 10405 to be converted into digital voltage signals, and then the digital voltage signals are sent to the microprocessor 10406. In this embodiment, the O-ring sealing technology is adopted for the sealing of the pressure and temperature parameter measurement assembly. The selected O-ring material is nitrile rubber, and the retaining ring material is polytetrafluoroethylene, and two seals are set.

[0048] The power supply I103 can supply power to the pressure sensor 10401, the temperature sensor 10402, the first signal conditioning circuit 10403, the second signal conditioning circuit 10404, the multi-channel A / D converter 10405, and the microprocessor 10406 of the pressure and temperature parameter measurement assembly 104.

[0049] The communication interface 105 can realize the communication connection between the downhole signal processor and the pressure and temperature parameter measurement assembly. The downhole signal processor 106 can read the data collected by the pressure and temperature parameter measurement assembly transmitted by the communication interface 105, select the modulation method and the center frequency, and then transmit it to the electromagnetic wave transmitter for processing.

[0050] The electromagnetic wave transmitter 107 includes an electromagnetic wave transceiver module 10701 and an electromagnetic wave transmitting antenna 10702. The electromagnetic wave transceiver module 10701 can convert the pressure and temperature information measured by the pressure and temperature parameter measurement assembly into a low-frequency electromagnetic wave signal through modulation, and after voltage and power amplification, it is transmitted to the extraction string and the formation through the electromagnetic wave transmitting antenna 10702. The modulation methods include frequency shift keying, phase shift keying, spread spectrum modulation, and pulse modulation. In this embodiment, the pulse modulation is adopted as the modulation method. The electromagnetic wave transmitting antenna 10702 adopts a dipole antenna. In this embodiment, the electromagnetic wave transmitting antenna 10702 adopts a steel rod, and preferably non-metallic materials such as ceramics and carbon fiber are used as isolation materials to realize the insulation and transmission at both ends of the dipole antenna.

[0051] The fluid-driven generator 101 is lowered into the well along with the drainage pipe string and is connected to the rechargeable battery 102. In this embodiment, the power generation principle of the fluid-driven generator 101 is to use the drainage water flow of the drainage pipe string to provide a high-speed fluid to impact the guide vane blades to generate a rotational torque, driving the turbine and the turbine rotating shaft to rotate at high speed. When the turbine rotating shaft rotates, it drives the permanent magnet rotor to rotate, cutting the magnetic induction lines in the coil to generate an induced electromotive force. After rectification, filtering, and voltage stabilization processing, the required electrical energy is obtained.

[0052] The power supply II 201 is respectively connected to the wellhead antenna 202, the wellhead electromagnetic wave processor 203, the wellhead signal processor 204, the wellhead industrial control computer and the display 205; the wellhead electromagnetic wave processor 203, the industrial control computer and the display 205 are all connected to the wellhead signal processor 204; both ends of the wellhead antenna 202 are respectively connected to the wellhead electromagnetic wave processor 203 and the electromagnetic wave transmitter 107.

[0053] The wellhead antenna 202 can receive the electromagnetic waves transmitted from the underground. The wellhead electromagnetic wave processor 203 converts the transmitted electromagnetic wave signals into electrical signals, and after amplification, noise reduction, filtering and other processing, it performs analog-to-digital conversion. The digital signals after analog-to-digital conversion are connected to the wellhead signal processor 204 for processing and analysis. The industrial control computer and the display module 205 are used for data processing, storage and display. In the embodiment, a noise amplifier is used to amplify the received weak electrical signals while reducing the increase of noise. A filter is used to remove the noise and unnecessary frequency components in the signal to improve the signal quality. The filter can be of low-pass, high-pass, band-pass or band-stop type. The role of the demodulator is to extract the original information signal from the received electromagnetic wave signals. An analog-to-digital converter is used to convert the analog electrical signals into digital signals.

[0054] Embodiment 2:

[0055] This embodiment provides a wireless acquisition method for coalbed methane well drainage parameters based on electromagnetic wave signals, and this method is implemented based on the wireless acquisition system for coalbed methane well drainage parameters based on electromagnetic wave signals in Embodiment 1; as Figure 2 shown, it includes the following steps:

[0056] Step 1: Assemble the well drainage pipe string including the electromagnetic wave transmission subsystem 1 in the coalbed methane well and lower it into the well according to the drainage design;

[0057] In this embodiment, in combination with the well depth of the drainage well, first select a suitable electromagnetic wave frequency and select a wireless acquisition system for coalbed methane well drainage parameters that matches the electromagnetic wave frequency.

[0058] Step 2: The rechargeable battery 102 powers other electrical systems of the electromagnetic wave transmission subsystem 1 in the coalbed methane well. The electromagnetic wave transmission subsystem 1 in the well collects bottom-hole flowing pressure and bottom-hole temperature data, modulates low-frequency electromagnetic wave signals, and transmits and collects low-frequency electromagnetic wave transmission signals. The coalbed methane wellhead electromagnetic wave receiving subsystem 2 receives the low-frequency electromagnetic waves, and processes the low-frequency electromagnetic wave signals such as noise reduction, filtering, demodulation, and modulation to obtain the bottom-hole flowing pressure and bottom-hole temperature data;

[0059] Step 3: Based on the drainage and production data such as the bottom-hole flowing pressure and bottom-hole temperature, formulate a drainage and production system and carry out drainage and pressure reduction;

[0060] Step 4: During drainage and production, the drainage water flow of the drainage string drives the downhole hydraulic generator 101 to generate electricity, realizing the charging of the rechargeable battery 102;

[0061] Step 5: When the water production volume is less than the water volume requirement of the downhole hydraulic generator, it is solved by increasing the drainage volume and injecting the drained water back into the wellhead.

[0062] In this embodiment, when the water production volume is less than 1 m 3 / d, after increasing the drainage volume, the drained water is directly injected back into the wellhead at the wellhead to meet the power generation water volume of the downhole hydraulic generator while maintaining the purpose of pressure reduction according to a reasonable liquid drainage volume. At the same time, in combination with the charging time and endurance of the rechargeable battery, the method of intermittently increasing the drainage volume and injecting the drained water back into the wellhead can also be adopted. After the rechargeable battery is fully charged, the drainage volume is adjusted back to the normal value.

[0063] The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solutions of the present invention, and these simple modifications all fall within the protection scope of the present invention.

[0064] In addition, it should be noted that, among the various specific technical features described in the above specific embodiments, they can be combined in any appropriate manner without conflict. To avoid unnecessary repetition, the present invention will not separately describe various possible combination methods.

[0065] In addition, any combination can be made between various different embodiments of the present invention as long as it does not violate the idea of the present invention, and it should also be regarded as the content disclosed by the present invention.

Claims

1. A wireless acquisition system for coalbed methane well drainage parameters based on electromagnetic wave signals, characterized in that: It includes an electromagnetic wave transmission subsystem (1) in a coalbed methane well and an electromagnetic wave receiving subsystem (2) at the coalbed methane wellhead; The electromagnetic wave transmission subsystem (1) in the coalbed methane well comprises a pressure and temperature parameter measurement assembly (104), a communication interface (105), an in-well signal processor (106), an electromagnetic wave transmitter (107), a power source I (103), a rechargeable battery (102), and a hydraulic generator (101); and is used to realize the collection and wireless transmission of pressure and temperature parameters; The coalbed methane wellhead electromagnetic wave receiving subsystem (2) comprises a power supply II (201), a wellhead antenna (202), a wellhead electromagnetic wave receiver (203), a wellhead signal processor (204), a wellhead industrial computer and a display (205); and is used for performing noise reduction, filtering, demodulation and modulation processing on electromagnetic wave signals to obtain bottom hole flow pressure and bottom hole temperature data.

2. The wireless acquisition system for coalbed methane well drainage parameters based on electromagnetic wave signals according to claim 1, characterized in that: The production-following hydraulic generator (101) is connected to a rechargeable battery (102); the rechargeable battery (102) is connected to a pressure and temperature parameter measurement assembly (104), a communication interface (105), an in-well signal processor (106), and an electromagnetic wave transmitter (107); and the in-well signal processor (106) is connected to the electromagnetic wave transmitter (107) and the communication interface (105).

3. The wireless acquisition system for coalbed methane well drainage parameters based on electromagnetic wave signals according to claim 1 is characterized in that: The pressure and temperature parameter measurement assembly (104) comprises a pressure sensor (10401), a temperature sensor (10402), a first signal conditioning circuit (10403), a second signal conditioning circuit (10404), a multi-channel A / D converter (10405), and a microprocessor (10406), and is used to obtain the bottom hole flow pressure and bottom hole temperature at the location of the parameter measurement assembly in the coalbed methane well; The pressure sensor (10401) and the temperature sensor (10402) are connected to a multi-channel A / D converter (10405) via a first signal conditioning circuit (10403) and a second signal conditioning circuit (10404), respectively, and the multi-channel A / D converter (10405) is connected to a microprocessor (10406).

4. The wireless acquisition system for coalbed methane well drainage parameters based on electromagnetic wave signals according to claim 3 is characterized in that: The pressure sensor (10401) and the temperature sensor (10402) obtain original analog voltage signals, which are amplified and filtered by the first signal conditioning circuit (10403) and the second signal conditioning circuit (10404) and then sent to the multi-channel A / D converter (10405) to be converted into digital voltage signals, and then the digital voltage signals are sent to the microprocessor (10406).

5. The wireless acquisition system for coalbed methane well drainage parameters based on electromagnetic wave signals according to claim 3 is characterized in that: The power supply I (103) can supply power to the pressure sensor (10401), the temperature sensor (10402), the first signal conditioning circuit (10403), the second signal conditioning circuit (10404), the multi-channel A / D converter (10405), and the microprocessor (10406) of the pressure and temperature parameter measurement assembly (104).

6. The wireless acquisition system for coalbed methane well drainage parameters based on electromagnetic wave signals according to claim 1, characterized in that: The communication interface (105) can realize the communication connection between the signal processor in the well and the pressure and temperature parameter measurement assembly; The well signal processor (106) can read the data collected by the pressure and temperature parameter measurement assembly transmitted from the communication interface (105), select the modulation mode and center frequency, and then transmit them to the electromagnetic wave transmitter for processing.

7. The wireless acquisition system for coalbed methane well drainage parameters based on electromagnetic wave signals according to claim 1, characterized in that: The electromagnetic wave transmitter (107) comprises an electromagnetic wave transceiver module (10701) and an electromagnetic wave transmitting antenna (10702); the electromagnetic wave transceiver module (10701) can convert the pressure and temperature information measured by the pressure and temperature parameter measurement assembly into a low-frequency electromagnetic wave signal through modulation, and transmit it to the extraction pipe column and the formation through the electromagnetic wave transmitting antenna (10702) after voltage and power amplification; The electromagnetic wave transmitting antenna (10702) adopts a dipole antenna.

8. The wireless acquisition system for coalbed methane well drainage parameters based on electromagnetic wave signals according to claim 1, characterized in that: The power supply II (201) is respectively connected to a wellhead antenna (202), a wellhead electromagnetic wave processor (203), a wellhead signal processor (204), a wellhead industrial computer and a display (205); the wellhead electromagnetic wave processor (203), the industrial computer and the display (205) are all connected to the wellhead signal processor (204); and two ends of the wellhead antenna (202) are respectively connected to the wellhead electromagnetic wave processor (203) and the electromagnetic wave transmitter (107).

9. The wireless acquisition system for coalbed methane well drainage parameters based on electromagnetic wave signals according to claim 8, characterized in that: The wellhead antenna (202) can receive electromagnetic waves transmitted from the well, and the wellhead electromagnetic wave processor (203) converts the transmitted electromagnetic wave signal into an electrical signal, and performs digital-to-analog conversion after amplification, noise reduction, and filtering. The digital signal after digital-to-analog conversion is connected to the wellhead signal processor (204) for processing and analysis. The industrial computer and display module (205) are used for data processing, storage, and display.

10. A method for wirelessly collecting coalbed methane well drainage parameters based on electromagnetic wave signals, characterized in that: The method is implemented based on the wireless acquisition system for coalbed methane well drainage parameters based on electromagnetic wave signals as described in any one of claims 2 to 9; and comprises the following steps: Step 1: Assemble the well drainage and production string including the electromagnetic wave transmission subsystem in the coalbed methane well, and lower it into the well according to the drainage and production design; Step 2: The rechargeable battery supplies power to other power systems of the electromagnetic wave transmission subsystem in the coalbed methane well. The electromagnetic wave transmission subsystem in the well collects bottom hole flow pressure and bottom hole temperature data, performs low-frequency electromagnetic wave signal modulation, transmits low-frequency electromagnetic wave transmission signal collection, uses the coalbed methane wellhead electromagnetic wave receiving subsystem to receive low-frequency electromagnetic waves, performs noise reduction, filtering, demodulation, and modulation processing on the low-frequency electromagnetic wave signal, and obtains bottom hole flow pressure and bottom hole temperature data; Step 3: Combine the bottom hole flow pressure and bottom hole temperature with the drainage number to formulate a drainage system and conduct drainage and pressure reduction; Step 4: During the drainage process, the drainage water flow of the drainage pipe string drives the hydraulic generator to generate electricity, thereby charging the rechargeable battery; Step 5: When the water production is less than the water requirement of the hydraulic generator, the problem is solved by increasing the drainage volume and reinjecting the produced water at the wellhead.

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