High-precision time synchronization multi-parameter underground acoustic positioning system and method

Abstract

The invention belongs to the technical field of underground acoustic positioning, and particularly relates to a high-precision time synchronization multi-parameter underground acoustic positioning system and method, and the system comprises an acoustic signal transmitter, a power amplifier, a transmitting transducer, a reciprocal transducer, a temperature sensor, a pressure sensor, a PTP clock, a data processing module, a receiving transducer, a main control display and the like. A transmitting transducer and a reciprocal transducer are synchronized through a time synchronization technology, temperature and pressure change data of a temperature sensor and a pressure sensor are combined, signal resolving and distance calculation are performed, positioning information of the reciprocal transducer is finally obtained, and various data are visualized through a main control display. Meanwhile, the multi-parameter underground acoustic positioning system further has a standby function, and the system can be in a standby state when measurement is stopped. The problem of low positioning precision is solved, underground acoustic positioning can be achieved, and the method has the advantages of being high in positioning precision, wide in dynamic measurement range and capable of working for a long time.

Description

Technical Field

[0001] The invention belongs to the technical field of downhole acoustic positioning, and in particular relates to a high-precision time-synchronized multi-parameter downhole acoustic positioning system and method. Background Art

[0002] Downhole acoustic positioning technology is a technology that uses sound waves to determine the location of target objects or equipment in closed environments such as oil and gas wells and underground pipelines. Compared with electromagnetic wave positioning, sound waves are not easily affected by electromagnetic interference, and have better propagation effects and less attenuation in liquid media, thus providing more stable and accurate positioning signals in environments such as oil and gas wells and underground pipelines. This makes acoustic positioning technology widely used in complex downhole environments, which is of great significance to ensuring production safety and improving work efficiency.

[0003] In practical applications, due to the complexity of the underground environment, positioning accuracy is often affected by environmental noise and reflection. High-precision time synchronization technology can ensure time synchronization between each measurement point, greatly reducing positioning errors caused by time deviation. In addition, the use of multi-parameter acoustic positioning technology can more effectively cope with environmental changes and complex conditions, and effectively reduce the impact of environmental noise, reflection and multipath effects on positioning. This technology has significant advantages, especially in special places such as oil and gas wells, underground pipelines and narrow spaces. By combining multi-parameter acoustic positioning with high-precision time synchronization technology, downhole acoustic positioning can be more accurate and stable in complex environments, thereby improving work efficiency and effectively reducing risks. Summary of the invention

[0004] In view of the above, the present invention provides a high-precision time-synchronized multi-parameter downhole acoustic positioning system and method, which can achieve downhole acoustic positioning and has the advantages of high positioning accuracy, wide dynamic measurement range and long-term operation.

[0005] The present invention provides the following technical solutions:

[0006] A high-precision time-synchronized multi-parameter downhole acoustic positioning system and method, comprising: an acoustic signal transmitter, used to generate a pulse signal within a working frequency band, and having functions such as adjusting signal frequency and amplitude; a power amplifier, used to amplify the power of the pulse signal; a transmitting transducer, used to transmit the power-amplified signal to the downhole; a reciprocal transducer, used to receive the acoustic signal transmitted from the wellhead, and after receiving the signal, return a signal containing information of each parameter and an unprocessed original acquisition signal from the downhole; a temperature sensor and a pressure sensor, used to measure the temperature and pressure changes of the reciprocal transducer from the wellhead to different positions downhole, in addition to the two physical parameters of temperature and pressure, other physical parameter sensors can also be expanded according to the function; a transmitting PTP clock and a receiving PTP clock, used to achieve time synchronization and record the time of acoustic signal transmission and reception, wherein PT The P clock is the Precision Time Protocol clock, referred to as PTP; the data processing module is located inside the reciprocal transducer, and demodulates and processes the collected acoustic signal by combining temperature, pressure and time information; the receiving transducer is used to receive the signal transmitted by the downhole reciprocal transducer, and demodulates the received signal through its internal data demodulation module, and the data storage module stores the demodulated signal containing various parameter information and the unprocessed original collected signal; the main control display is used to visualize the downhole measurement information demodulated by the receiving transducer, remotely control the emission and stop of the transmitting transducer, and receive prompt information on the success or failure of the positioning sent by the reciprocal transducer and the receiving transducer; the oil and gas well is used to complete the entire process of downhole acoustic positioning; at the same time, the multi-parameter downhole acoustic positioning system also has a standby function, and the system will be in standby state when the measurement is stopped.

[0007] The output end of the acoustic signal transmitter is connected to the input end of the power amplifier, the output end of the power amplifier is connected to the input end of the transmitting transducer, the transmitting PTP clock is located inside the transmitting transducer, one end of the main control display is connected to the output end of the receiving transducer, and the other end is connected to the input end of the transmitting transducer, the reciprocal transducer has a temperature sensor, a pressure sensor, a receiving PTP clock and a data processing module inside, and the receiving transducer has a data storage module and a data demodulation module inside.

[0008] Preferably, the signal generated by the acoustic signal transmitter is a pulse signal, the frequency range of which is determined according to the characteristics of the waveguide channel in the pipeline, and has the function of adjusting the signal frequency, amplitude, etc.

[0009] Preferably, the power amplifier amplifies the power of the acoustic signal linearly and has the function of adjusting the power size.

[0010] Preferably, the transmitting transducer, reciprocal transducer and receiving transducer have the characteristics of high precision, wide measurement range and high stability; after receiving the signal, the reciprocal transducer will return a signal containing various parameter information and an unprocessed original acquisition signal from the downhole, and after receiving the signal transmitted by the reciprocal transducer, the receiving transducer will demodulate the received signal through its internal data demodulation module, and the data storage module will store the demodulated signal containing various parameter information and the unprocessed original acquisition signal.

[0011] Preferably, the measurement errors of the temperature sensor and the pressure sensor are ±1° C. and ±1% FS respectively, and the collected data are the temperature and pressure at different positions from the wellhead to the wellbore.

[0012] Preferably, the synchronization accuracy of the transmitting PTP clock and the receiving PTP clock is 20ns, and the frequency stability is 1ppb.

[0013] Preferably, the sampling frequency of the reciprocal transducer and the receiving transducer is the product of the acoustic signal frequency and the sampling time, and the acoustic communication between the reciprocal transducer and the receiving transducer is always matched.

[0014] Preferably, the main control display has the functions of visualizing the downhole measurement information demodulated by the receiving transducer; remotely controlling the emission and stop of the transmitting transducer; receiving and displaying prompt information on the success or failure of positioning sent by the reciprocal transducer and the receiving transducer; highlighting the positioning information of the reciprocal transducer in the downhole; and remotely adjusting the signal sound pressure value emitted by the reciprocal transducer.

[0015] Preferably, the oil and gas well is a light crude oil well and is not interfered by external signals.

[0016] Preferably, the multi-parameter downhole acoustic positioning system has a standby function, and the system will be in a standby state when the measurement is stopped.

[0017] A method for a high-precision time-synchronized multi-parameter downhole acoustic positioning system as described above, wherein the acoustic signal transmitter amplifies the power of the acoustic signal through the power amplifier, and transmits the acoustic signal to the downhole through the transmitting transducer, and at the same time the transmitting PTP clock starts timing, after the reciprocal transducer receives the acoustic signal, the temperature sensor, the pressure sensor and the receiving PTP clock respectively collect temperature, pressure and time information, the data processing module demodulates and processes the collected data information to obtain the positioning information of the reciprocal transducer, and then transmits a signal containing various downhole parameter information and an unprocessed original collected signal to the wellhead through the reciprocal transducer, the receiving transducer receives the signal transmitted by the reciprocal transducer downhole, and demodulates the received signal through the data demodulation module inside it, the data storage module stores the demodulated signal containing various parameter information and the unprocessed original collected signal, and finally the downhole measurement information demodulated by the receiving transducer is visualized through the main control display, and the positioning information of the reciprocal transducer downhole is highlighted, and the specific implementation method is as follows:

[0018] Step 1: Place the reciprocal transducer in the well, and ensure that the reciprocal transducer is not damaged during the placement process and has good signal receiving and sending functions. Similarly, ensure that the temperature sensor, pressure sensor, receiving PTP clock and data processing module inside the reciprocal transducer are not damaged during the placement process and have good signal acquisition, demodulation and processing functions;

[0019] Step 2: Install and fix the acoustic signal transmitter, power amplifier and main control display at the wellhead, install and fix the transmitting transducer and receiving transducer on both sides of the liquid surface in the well respectively, and ensure that the transmitting transducer and receiving transducer are not damaged during the installation and placement process and have good signal transmission function. At the same time, ensure that the transmitting PTP clock, data storage module and data demodulation module are not damaged during the placement process and have good time synchronization and timing, data storage and data demodulation functions respectively.

[0020] Step 3: The acoustic signal transmitter transmits an acoustic signal to the well through a power amplifier and a transmitting transducer. The frequency of the signal is f s , the sound pressure value of the signal is P1, the transmitting PTP clock records the time as t1, and the receiving PTP clock receives the signal at t2, then the signal propagation time t = t2-t1, and the signal propagation time is divided into t·f according to the signal frequency s The temperature value measured by the temperature sensor is The pressure value measured by the pressure sensor is

[0021] If the reciprocal transducer does not receive the acoustic signal emitted by the transmitting transducer, it will send a prompt message to the main control display, and then the power amplifier will automatically adjust the power. If the receiving transducer does not receive the acoustic signal emitted by the reciprocal transducer, it will also send a prompt message to the main control display, and then remotely adjust the sound pressure value of the acoustic signal emitted by the reciprocal transducer.

[0022] Step 4: Liquid density ρ of the nth section in the oil and gas well n The corresponding temperature T n and pressure P n The relational expression is:

[0023] ρ n (T,P)=ρ0(1-β(T n -T0)+δP n )n=1,2,3...t·f s Where ρ0 is the density of light crude oil under standard conditions, which is 0.82 g / cm 3 , β is the thermal expansion coefficient of light crude oil, which is 0.00091 / ℃, the reference temperature T0 is 15℃, δ=1.5×10- 5 Pa- 1 is the pressure coefficient of light crude oil.

[0024] The relationship between the bulk modulus Kn of the nth section in the oil and gas well and the corresponding temperature Tn and pressure Pn is expressed as:

[0025]

[0026] Wherein, K0=1500MPa is the bulk modulus of light crude oil at standard temperature and pressure, and γ=0.00071 / ℃ is the temperature coefficient of light crude oil.

[0027] The relationship between the sound velocity cn(T, P) of the nth section in the oil and gas well and the density ρn(T, P) and the bulk modulus Kn(T, P) is expressed as follows:

[0028]

[0029] Obtain cn(T,P) and multiply it with each time segment dt=tn-tn-1 (n=1,2,3 ...t·fs and t0=0) and then sum it. That is, the relationship between the position information of the reciprocal transducer and each segment of speed and time is expressed as:

[0030]

[0031] Finally, the position information s of the reciprocal transducer is obtained, and the position s of the reciprocal transducer demodulated by the receiving transducer and the temperature of the well are displayed through the main control display. and pressure As well as time t visualization, the positioning information of the reciprocal transducer in the well is highlighted.

[0032] In general, the technical solution conceived by the present invention can achieve the following beneficial effects compared with the prior art:

[0033] The present invention proposes a high-precision time-synchronized multi-parameter downhole acoustic positioning system and method, which has the advantages of high positioning accuracy, wide dynamic measurement range and long-term operation, and is convenient for real-time data acquisition and communication transmission. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a module diagram of a high-precision time-synchronized multi-parameter downhole acoustic positioning system of the present invention;

[0035] Figure 2 It is a positioning schematic diagram of a high-precision time-synchronized multi-parameter downhole acoustic positioning system of the present invention;

[0036] Figure 3 It is a schematic diagram of synchronous time positioning of a high-precision time synchronous multi-parameter downhole acoustic positioning system of the present invention;

[0037] The following are marked in the figure:

[0038] 1-acoustic signal transmitter; 2-power amplifier; 3-transmitting transducer; 4-transmitting PTP clock; 5-reciprocal transducer; 6-temperature sensor; 7-pressure sensor; 8-receiving PTP clock; 9-data processing module; 10-receiving transducer; 11-data storage module; 12-data demodulation module; 13-main control display; 14-oil and gas well. DETAILED DESCRIPTION

[0039] The specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings so that those skilled in the art can more clearly understand how to practice the present invention. Although the present invention is described in conjunction with its preferred specific embodiments, these embodiments are only illustrative and are not intended to limit the scope of the present invention.

[0040] Combined with Figure 1As shown, a high-precision time-synchronized multi-parameter downhole acoustic positioning system comprises: an acoustic signal transmitter 1, which is used to generate a pulse signal within a working frequency band and has functions such as adjusting the signal frequency and amplitude; a power amplifier 2, which is used to amplify the pulse signal; a transmitting transducer 3, which is used to transmit the power-amplified signal to the downhole; a reciprocal transducer 5, which is used to receive the acoustic signal transmitted from the wellhead, and after receiving the signal, return a signal containing information of various parameters and an unprocessed original acquisition signal from the downhole; a temperature sensor 6 and a pressure sensor 7, which are used to measure the temperature and pressure changes of the reciprocal transducer 5 from the wellhead to different positions downhole. In addition to the two physical parameters of temperature and pressure, other physical parameter sensors can also be expanded according to the function; a transmitting PTP clock 4 and a receiving PTP clock 8, which are used to achieve time synchronization and record the time of transmitting and receiving the acoustic signal, wherein the PTP clock is a precise The embodiment of the present invention is a time confirmation protocol clock, referred to as PTP; a data processing module 9, which is located inside the reciprocal transducer 5, demodulates and processes the collected acoustic signal by combining temperature, pressure and time information; a receiving transducer 10, which is used to receive the signal transmitted by the downhole reciprocal transducer 5, and demodulates the received signal through its internal data demodulation module 12, and the data storage module 11 stores the demodulated signal containing various parameter information and the unprocessed original collected signal; a main control display 13, which is used to visualize the downhole measurement information demodulated by the receiving transducer 10, remotely control the emission and stop of the transmitting transducer 3, and receive prompt information on whether the positioning is successful or not sent by the reciprocal transducer 5 and the receiving transducer 10; an oil and gas well 14, which is used to complete the entire process of downhole acoustic positioning; at the same time, the multi-parameter downhole acoustic positioning system also has a standby function, and the system will be in a standby state when the measurement is stopped.

[0041] The output end of the acoustic signal transmitter 1 is connected to the input end of the power amplifier 2, the output end of the power amplifier 2 is connected to the input end of the transmitting transducer 3, the transmitting PTP clock 4 is located inside the transmitting transducer 3, one end of the main control display 13 is connected to the output end of the receiving transducer 10, and the other end is connected to the input end of the transmitting transducer 3, the reciprocal transducer 5 has a temperature sensor 6, a pressure sensor 7, a receiving PTP clock 8 and a data processing module 9 inside, and the receiving transducer 10 has a data storage module 11 and a data demodulation module 12 inside.

[0042] Specifically, the signal generated by the acoustic signal transmitter 1 is a pulse signal, the frequency range of which is determined according to the characteristics of the waveguide channel in the pipeline, and has the function of adjusting the signal frequency, amplitude, etc.

[0043] Specifically, the power amplifier 2 performs linear amplification on the power of the acoustic signal and has the function of adjusting the power size.

[0044] Specifically, the transmitting transducer 3, the reciprocal transducer 5 and the receiving transducer 10 have the characteristics of high precision, wide measurement range and high stability; after receiving the signal, the reciprocal transducer 5 will return a signal containing various parameter information and an unprocessed original acquisition signal from the downhole, and after receiving the signal transmitted by the reciprocal transducer 5, the receiving transducer 10 will demodulate the received signal through its internal data demodulation module 12, and the data storage module 11 will store the demodulated signal containing various parameter information and the unprocessed original acquisition signal.

[0045] Specifically, the measurement errors of the temperature sensor 6 and the pressure sensor 7 are ±1° C. and ±1% FS respectively, and the collected data are the temperature and pressure at different positions from the wellhead to the wellbore.

[0046] Specifically, the synchronization accuracy of the transmitting PTP clock 4 and the receiving PTP clock 8 is 20ns, and the frequency stability is 1ppb.

[0047] Specifically, the sampling frequency of the reciprocal transducer 5 and the receiving transducer 10 is the product of the acoustic signal frequency and the sampling time, and the acoustic communication between the reciprocal transducer 5 and the receiving transducer 10 is always matched.

[0048] Specifically, the main control display 13 has the functions of visualizing the downhole measurement information demodulated by the receiving transducer 10; remotely controlling the emission and stop of the transmitting transducer 3; receiving and displaying prompt information on whether the positioning is successful or not sent by the reciprocal transducer 5 and the receiving transducer 10; highlighting the positioning information of the reciprocal transducer 5 in the downhole; and remotely adjusting the signal sound pressure value emitted by the reciprocal transducer 5.

[0049] Specifically, the oil and gas well 14 is a light crude oil well and is not interfered by external signals.

[0050] Specifically, the multi-parameter downhole acoustic positioning system has a standby function, and the system will be in a standby state when the measurement is stopped.

[0051] Combination Figure 2 and Figure 3As shown, a method of the high-precision time-synchronized multi-parameter downhole acoustic positioning system as described above, the acoustic signal transmitter 1 amplifies the power of the acoustic signal through the power amplifier 2, and transmits the acoustic signal to the downhole through the transmitting transducer 3, and at the same time the transmitting PTP clock 4 starts timing, after the reciprocal transducer 5 receives the acoustic signal, the temperature sensor 6, the pressure sensor 7 and the receiving PTP clock 8 respectively collect temperature, pressure and time information, the data processing module 9 demodulates and processes the collected data information, thereby obtaining the positioning information of the reciprocal transducer 5, and then passes The reciprocal transducer 5 transmits a signal containing various downhole parameter information and an unprocessed original acquisition signal to the wellhead, the receiving transducer 10 receives the signal transmitted by the reciprocal transducer 5 downhole, and demodulates the received signal through the data demodulation module 12 inside it, and the data storage module 11 stores the demodulated signal containing various parameter information and the unprocessed original acquisition signal, and finally the downhole measurement information demodulated by the receiving transducer 10 is visualized through the main control display 13, and the positioning information of the reciprocal transducer 5 downhole is highlighted, and the specific implementation method is as follows:

[0052] Step 1: Place the reciprocal transducer 5 in the well, and ensure that the reciprocal transducer 5 is not damaged during the placement process and has good signal receiving and sending functions. Similarly, ensure that the temperature sensor 6, pressure sensor 7, receiving PTP clock 8 and data processing module 9 inside the reciprocal transducer 5 are not damaged during the placement process and have good signal acquisition, demodulation and processing functions;

[0053] Step 2: Install and fix the acoustic signal transmitter 1, the power amplifier 2 and the main control display 13 at the wellhead position, install and fix the transmitting transducer 3 and the receiving transducer 10 on both sides of the downhole liquid surface respectively, and ensure that the transmitting transducer 3 and the receiving transducer 10 are not damaged during the installation and placement process and have good signal transmission function, and at the same time ensure that the transmitting PTP clock 4, the data storage module 11 and the data demodulation module 12 are not damaged during the placement process and have good time synchronization and timing, data storage and data demodulation functions respectively.

[0054] Step 3: The acoustic signal transmitter 1 transmits an acoustic signal to the well through the power amplifier 2 and the transmitting transducer 3. The frequency of the signal is f s , the sound pressure value of the signal is P1, the time recorded by the transmitting PTP clock 4 is t1, and the time when the receiving PTP clock 8 receives the signal is t2, then the signal propagation time t=t2-t1, and the signal propagation time is divided into t·f according to the signal frequency s The temperature value measured by temperature sensor 6 is The pressure value measured by the pressure sensor 7 is

[0055] If the reciprocal transducer 5 does not receive the acoustic signal transmitted by the transmitting transducer 3, a prompt message is sent to the main control display 13, and the power amplifier 2 automatically adjusts the power. If the receiving transducer 10 does not receive the acoustic signal transmitted by the reciprocal transducer 5, a prompt message is also sent to the main control display 13, and the sound pressure value of the acoustic signal transmitted by the reciprocal transducer 5 is remotely adjusted.

[0056] Step 4: Liquid density ρ of the nth section in the oil and gas well 14 n The corresponding temperature T n and pressure P n The relational expression is:

[0057] ρ n (T,P)=ρ0(1-β(T n -T0)+ρP n )n=1,2,3...t·f s Where ρ0 is the density of light crude oil under standard conditions, which is 0.82 g / cm 3 , β is the thermal expansion coefficient of light crude oil, which is 0.00091 / ℃, the reference temperature T0 is 15℃, δ=1.5×10 -5 Pa -1 is the pressure coefficient of light crude oil.

[0058] The bulk modulus K of the nth section in the oil and gas well 14 n The corresponding temperature T n and pressure P n The relational expression is:

[0059]

[0060] Wherein, K0=1500MPa is the bulk modulus of light crude oil at standard temperature and pressure, and γ=0.00071 / ℃ is the temperature coefficient of light crude oil.

[0061] The sound velocity c of the nth section in the oil and gas well 14 n (T,P) and density ρ n (T,P) and bulk modulus K n The relational expression of (T, P) is:

[0062]

[0063] Get c n (T,P) and each time dt = t n -t n-1 (n=1,2,3...t·f sand t0=0), multiplied and then summed, that is, the relationship between the position information of the reciprocal transducer 5 and the speed and time of each segment is expressed as:

[0064]

[0065] Finally, the position information s of the reciprocal transducer 5 is obtained, and the position s of the reciprocal transducer 5 demodulated by the receiving transducer 10 and the temperature of the well are displayed through the main control display 13. and pressure As well as time t visualization, the positioning information of the reciprocal transducer 5 in the well is highlighted.

[0066] The above description of the embodiments is to facilitate the understanding and application of the present invention by those skilled in the art. It is obvious that those skilled in the art can easily make various modifications to the above embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the present invention is not limited to the above embodiments, and improvements and modifications made to the present invention by those skilled in the art based on the disclosure of the present invention should be within the scope of protection of the present invention.

Claims

1. A high-precision time-synchronized multi-parameter downhole acoustic positioning system, characterized in that: include: The acoustic signal transmitter (1) is used to generate a pulse signal within the working frequency band; the power amplifier (2) is used to amplify the power of the pulse signal; The transmitting transducer (3) is used to transmit the power-amplified signal to the wellbore; the reciprocal transducer (5) is used to receive the acoustic signal transmitted from the wellhead and, after receiving the signal, return a signal containing various parameter information and an unprocessed original collected signal from the wellbore; the temperature sensor (6) and the pressure sensor (7) are used to measure the temperature and pressure changes of the reciprocal transducer (5) from the wellhead to different positions in the wellbore; the transmitting PTP clock (4) and the receiving PTP clock (8) are used to achieve time synchronization and record the time of transmitting and receiving the acoustic signal; the data processing module (9) is located inside the reciprocal transducer (5) and demodulates and processes the collected acoustic signal by combining the temperature, pressure and time information; the receiving transducer (10) , used to receive the signal transmitted by the downhole reciprocal transducer (5), and demodulate the received signal through its internal data demodulation module (12), and the data storage module (11) stores the demodulated signal containing various parameter information and the unprocessed original acquisition signal; the main control display (13) is used to visualize the downhole measurement information demodulated by the receiving transducer (10), remotely control the transmission and stop of the transmitting transducer (3), and receive the prompt information of whether the positioning is successful or not sent by the reciprocal transducer (5) and the receiving transducer (10); the oil and gas well (14) is used to complete the entire process of downhole acoustic positioning; at the same time, the multi-parameter downhole acoustic positioning system also has a standby function, and the system will be in a standby state when the measurement is stopped; The output end of the acoustic signal transmitter (1) is connected to the input end of the power amplifier (2), the output end of the power amplifier (2) is connected to the input end of the transmitting transducer (3), the transmitting PTP clock (4) is located inside the transmitting transducer (3), one end of the main control display (13) is connected to the output end of the receiving transducer (10), and the other end is connected to the input end of the transmitting transducer (3), the reciprocal transducer (5) has a temperature sensor (6), a pressure sensor (7), a receiving PTP clock (8) and a data processing module (9) inside, and the receiving transducer (10) has a data storage module (11) and a data demodulation module (12) inside.

2. A high-precision time-synchronized multi-parameter downhole acoustic positioning system according to claim 1, characterized in that: The signal generated by the acoustic signal transmitter (1) is a pulse signal, and the frequency range is determined according to the characteristics of the waveguide channel in the pipeline.

3. The high-precision time-synchronized multi-parameter downhole acoustic positioning system according to claim 1, characterized in that: The power amplifier (2) amplifies the power of the sound signal linearly and adjusts the power size.

4. The high-precision time-synchronized multi-parameter downhole acoustic positioning system according to claim 1, characterized in that: The sampling frequency of the reciprocal transducer (5) and the receiving transducer (10) is the product of the acoustic signal frequency and the sampling time, and the acoustic communication between the reciprocal transducer (5) and the receiving transducer (10) is always matched.

5. The high-precision time-synchronized multi-parameter downhole acoustic positioning system according to claim 1, characterized in that: The main control display (13) has the functions of visualizing the downhole measurement information demodulated by the receiving transducer (10); and remotely controlling the emission and stop of the transmitting transducer (3); Receive and display prompt information on whether positioning is successful or not sent by the reciprocal transducer (5) and the receiving transducer (10); highlight the positioning information of the reciprocal transducer (5) in the well; and remotely adjust the signal sound pressure value emitted by the reciprocal transducer (5).

6. The high-precision time-synchronized multi-parameter downhole acoustic positioning method according to claim 1, characterized in that: include; The acoustic signal transmitter (1) amplifies the power of the acoustic signal through the power amplifier (2), and transmits the acoustic signal to the well through the transmitting transducer (3), and at the same time, the transmitting PTP clock (4) starts timing. After the reciprocal transducer (5) receives the acoustic signal, the temperature sensor (6), the pressure sensor (7) and the receiving PTP clock (8) respectively collect temperature, pressure and time information. The data processing module (9) demodulates and processes the collected data information to obtain the positioning information of the reciprocal transducer (5), and then transmits the positioning information to the wellhead through the reciprocal transducer (5). The receiving transducer (10) receives the signal emitted by the reciprocal transducer (5) in the well, and demodulates the received signal through the data demodulation module (12) inside the receiving transducer (10), and the data storage module (11) stores the demodulated signal containing the parameter information and the unprocessed original acquisition signal, and finally visualizes the demodulated well measurement information of the receiving transducer (10) through the main control display (13), and highlights the positioning information of the reciprocal transducer (5) in the well. The specific implementation method is as follows: Step 1: Place the reciprocal transducer (5) in the well, and ensure that the reciprocal transducer (5) is not damaged during the placement process and has good signal receiving and sending functions. Similarly, ensure that the temperature sensor (6), pressure sensor (7), receiving PTP clock (8) and data processing module (9) inside the reciprocal transducer (5) are not damaged during the placement process and have good signal acquisition, demodulation and processing functions; Step 2: Install and fix the acoustic signal transmitter (1), the power amplifier (2) and the main control display (13) at the wellhead position, install and fix the transmitting transducer (3) and the receiving transducer (10) on both sides of the downhole liquid surface respectively, and ensure that the transmitting transducer (3) and the receiving transducer (10) are not damaged during the installation and placement process and have good signal transmission functions, and at the same time ensure that the transmitting PTP clock (4), the data storage module (11) and the data demodulation module (12) are not damaged during the placement process and have good time synchronization and timing, data storage and data demodulation functions respectively; Step 3: The acoustic signal transmitter (1) transmits an acoustic signal to the wellbore through the power amplifier (2) and the transmitting transducer (3). The frequency of the signal is f s , the sound pressure value of the signal is P1, the time recorded by the transmitting PTP clock (4) is t1, and the time when the receiving PTP clock (8) receives the signal is t2, then the signal propagation time t = t2-t1, and the signal propagation time is divided into t·f according to the signal frequency s The temperature value measured by the temperature sensor (6) is The pressure value measured by the pressure sensor (7) is If the reciprocal transducer (5) does not receive the acoustic signal emitted by the transmitting transducer (3), a prompt message is sent to the main control display (13), and the power amplifier (2) automatically adjusts the power. If the receiving transducer (10) does not receive the acoustic signal emitted by the reciprocal transducer (5), a prompt message is also sent to the main control display (13), and the sound pressure value of the acoustic signal emitted by the reciprocal transducer (5) is remotely adjusted. Step 4: Liquid density ρ of the nth section in the oil and gas well (14) n The corresponding temperature T n and pressure P n The relational expression is: ρ n (T,P)=ρ0(1-β(T n -T0)+ρP n )n=1,2,3...t·f s Where ρ0 is the density of light crude oil under standard conditions, which is 0.82 g / cm 3 , β is the thermal expansion coefficient of light crude oil, which is 0.00091 / ℃, the reference temperature T0 is 15℃, δ=1.5×10 -5 Pa -1 is the pressure coefficient of light crude oil; The bulk modulus K of the nth section in the oil and gas well (14) n The corresponding temperature T n and pressure P n The relational expression is: Where, K0 = 1500 MPa is the bulk modulus of light crude oil at standard temperature and pressure, γ = 0.00071 / °C is the temperature coefficient of light crude oil; The sound velocity c of the nth section in the oil and gas well (14) n (T,P) and density ρ n (T,P) and bulk modulus K n The relational expression of (T, P) is: Get c n (T,P) and each time dt = t n -t n-1 (n=1,2,3...t·f s and t0=0), multiplied and then summed, that is, the relationship between the position information of the reciprocal transducer (5) and the speed and time of each segment is expressed as: Finally, the position information s of the reciprocal transducer (5) is obtained, and the position s of the reciprocal transducer (5) demodulated by the receiving transducer (10) and the temperature of the well are displayed through the main control display (13). and pressure As well as time t visualization, the positioning information of the reciprocal transducer (5) downhole is highlighted.

Images