CN113701851A

CN113701851A - Oil well liquid level measuring device and liquid level type measuring method

Info

Publication number: CN113701851A
Application number: CN202111150213.9A
Authority: CN
Inventors: 呼秀山; 李圆圆; 郝洪峰; 郝舜媛; 李丽君; 李军; 白波; 李丹丹; 张红岩; 董泓铄; 刘晓明
Original assignee: Beijing Ruida Instrument Co ltd
Current assignee: Beijing Ruida Instrument Co ltd
Priority date: 2021-09-29
Filing date: 2021-09-29
Publication date: 2021-11-26
Anticipated expiration: 2041-09-29
Also published as: CN113701851B

Abstract

The utility model provides an oil well liquid level measurement device, to the metal oil pipe transmission of oil well an electromagnetic wave signal, the electromagnetic wave signal is transmitted along metal oil pipe, meets oil level or water level and is reflected back and form echo signal, measuring device receives echo signal, thereby calculates out the position of oil or water through measuring the time difference of transmission signal and echo signal or the analysis contains the signal information of time difference. The disclosure also provides a method for measuring the oil well liquid level and the oil well liquid level type.

Description

Oil well liquid level measuring device and liquid level type measuring method

Technical Field

The present disclosure relates to an oil well liquid level measuring device and a liquid level, liquid level type measuring method.

Background

Currently, most of oil well liquid level measurement modes adopt echo positioning of a sonar system. After the sound wave is emitted by the emitter, the sound wave reaches the detection target through the transmission medium, then the sound wave is reflected by the target and returns to the emitting point, and the round trip time of the sound wave signal is obtained through processing, so that the liquid level is calculated. However, in practical application, the internal environment of the oil well is complex, and the distance measurement by the echo positioning method is easily influenced by factors such as a foam section in the oil well, so that measurement errors are caused.

The oil well liquid level is also measured by capacitance. The well casing and tubing annulus can be considered a cylindrical capacitor, with portions of the casing and tubing submerged in liquid due to the presence of groundwater downhole. Due to the different dielectric constants of downhole fluids and gases, the capacitance between the well casing and tubing changes as the fluid level in the well changes. And measuring the capacitance value between the casing and the oil pipe through a capacitance measuring device, and obtaining the underground liquid level height according to a theoretical relation between the capacitance and the liquid levels in the oil well casing and the oil pipe annulus. However, the environment in the oil well is complex, and the dielectric constant is affected by natural gas, water vapor, moisture, temperature change, uneven distribution of the casing and the oil pipe, and the like, and the liquid level measurement accuracy is also reduced due to the influence of the environment such as pressure, vacuum, inert gas, smoke dust, steam, and the like.

Disclosure of Invention

In order to solve at least one of the above technical problems, the present disclosure provides a well level measuring device and a level, level type measuring method.

According to one aspect of the disclosure, an oil well liquid level measuring device is provided, the measuring device transmits an electromagnetic wave signal to a metal oil pipe of an oil well, the electromagnetic wave signal is transmitted along the metal oil pipe, the electromagnetic wave signal is reflected back when encountering an oil level or a water level to form an echo signal, the measuring device receives the echo signal, and the position of oil or water is calculated by measuring the time difference between the transmitted and echo signals or analyzing signal information containing the time difference.

According to the oil well liquid level measuring device of at least one embodiment of the present disclosure, the electromagnetic wave signal is transmitted along the outer surface of the metal oil pipe.

The oil well liquid level measuring device according to at least one embodiment of the present disclosure includes:

a measurement unit connected to a signal level of the waveguide structure; and

a waveguide structure, comprising:

a ground stage connected to the casing of the oil well;

the signal stage is positioned in the grounding stage, has the same extension direction with the grounding stage, is connected with the measuring unit at one side, and extends to the metal oil pipe at the other side to be connected with the metal oil pipe;

an insulator between the signal stage and the ground stage to insulate the signal stage from the ground stage;

a first sealing body located between the signal stage and the insulator to seal the signal stage from the insulator;

a second sealing body located between the insulator and the ground electrode to seal the ground electrode and the insulator;

the signal stage of the waveguide structure can also move along the extension direction of the grounding stage, and can move towards the direction far away from the metal oil pipe when measurement is not needed.

The oil well liquid level measurement device according to at least one embodiment of the present disclosure, the measurement device further includes:

the handle is connected to one side, close to the measuring unit, of the signal level and used for moving the signal level to enable the signal level to be connected with or disconnected from the metal oil pipe;

a switch for controlling whether the signal stage is movable;

the baffle is connected with the oil well casing or the grounding level, is arranged outside the oil well casing and is used for limiting the maximum range of the movement of the signal level and avoiding the falling of the measuring unit and the signal level caused by overlarge distance of the movement range when the signal level moves to one side far away from the metal oil pipe in the extension direction of the grounding level; and an energy consumption structure, the energy consumption structure is arranged above the connection part of the signal level and the metal oil pipe and is used for reducing or eliminating the energy reflected back when the echo signal is vertically transmitted upwards along the metal oil pipe so that the echo signal vertically transmitted upwards has no influence on the liquid level measurement,

the energy consumption structure comprises a wave absorbing structure and/or an attenuation structure.

According to the oil well liquid level measuring device of at least one embodiment of the present disclosure, the wave impedance of the waveguide structure in the signal level direction is constant or has no abrupt change, and the waveguide structure includes a coaxial type.

According to the oil well liquid level measuring device of at least one embodiment of the present disclosure, the waveguide structure is one of a waveguide, a radio frequency cable and a microwave circuit.

According to the oil well liquid level measuring device of at least one embodiment of the present disclosure, the insulator is provided in a plurality and is uniformly distributed in the extending direction of the signal level.

According to the oil well liquid level measuring device of at least one embodiment of the present disclosure, the side of the signal stage connected with the metal oil pipe is concave.

According to the oil well liquid level measuring device of at least one embodiment of the present disclosure, the concave surface shape comprises a cylindrical shape, and a cylindrical surface can be well attached to the outer surface of an oil pipe.

According to the oil well liquid level measuring device of at least one embodiment of the present disclosure, the first sealing body comprises a sealing ring and/or a gasket, the first sealing body is perpendicular to the signal level, and the cross section of the sealing body has the same shape as that of the cross section of the signal level, so that the signal level and the sealing body are tightly attached; and/or the presence of a gas in the gas,

the second sealing body comprises a sealing ring and/or a gasket, the second sealing body is perpendicular to all cross sections of the grounding stage, the shape of the second sealing body is the same as that of all cross sections of the grounding stage, and the grounding stage and the second sealing body are tightly attached without a gap so as to prevent sloshing.

According to the oil well liquid level measuring device of at least one embodiment of the present disclosure, the measuring unit comprises one of a first circuit, a second circuit or a third circuit.

According to at least one embodiment of this disclosure, the oil well liquid level measurement device, the first circuit includes:

the signal transmitting module is connected with the distributor and the processor and used for generating and transmitting electromagnetic wave signals to the distributor;

the signal receiving module is connected with the distributor and the AD collector, comprises a probe and is used for receiving the echo signal transmitted to the distributor from the waveguide structure and transmitting the echo signal to the AD collector;

the distributor is connected with the signal transmitting module, the signal receiving module and the waveguide structure, transmits the electromagnetic wave signal transmitted by the signal transmitting module to the waveguide structure, and transmits the echo signal from the waveguide structure to the signal receiving module, and the distributor is one of a coupler circuit and a power divider circuit;

the AD collector is connected with the signal receiving module and the processor and is used for collecting echo signals from the signal receiving module and outputting digital signals to the processor;

the processor is connected with the power supply module, the AD collector and the signal transmitting module, controls the signal transmitting module to transmit different types of electromagnetic wave signals and records transmitting time information, acquires, processes and analyzes digital signals output by the AD collector, and outputs a processing result;

the power supply module is connected with the processor and used for supplying power to the processor;

the communication module enables the processor to be in communication connection with the display module through the communication module and transmits a processing result of the processor to the display module; and

and the display module is connected with the processor through the communication module and displays the processing result of the processor.

According to at least one embodiment of this disclosure, the oil well liquid level measurement device, the second circuit includes:

the signal transmitting module is connected with the difference frequency controller, the frequency mixer and the power amplifier, transmits a first signal to the frequency mixer and transmits a second signal to the power amplifier, wherein the first signal and the second signal have different frequencies, and the frequency of the first signal and the frequency of the second signal are calculated and controlled by the difference frequency controller;

the signal receiving module is connected with the distributor and the mixer, comprises a probe and is used for receiving the echo signal transmitted to the distributor from the waveguide structure and transmitting the echo signal to the mixer;

the distributor is connected with the power amplifier, the signal receiving module and the waveguide structure, receives a second signal amplified by the power amplifier and outputs the second signal to the waveguide structure, receives an echo signal from the waveguide structure and transmits the echo signal to the signal receiving module, and the distributor is one of a coupler circuit and a power divider circuit;

the power amplifier is connected with the signal transmitting module and the distributor, receives the second signal transmitted by the signal transmitting module, amplifies the power of the second signal and outputs the second signal after power amplification to the distributor;

the mixer is connected with the signal transmitting module, the signal receiving module and the intermediate frequency amplifying filter, receives a first signal transmitted by the signal transmitting module and an echo signal from the signal receiving module, mixes the first signal and the echo signal to obtain an echo signal time broadening signal, and outputs the echo signal time broadening signal to the intermediate frequency amplifying filter;

the intermediate frequency amplification filter is connected with the frequency mixer and the AD collector, receives the echo signal time broadening signal output by the frequency mixer, performs intermediate frequency amplification filtering and filtering on the echo signal time broadening signal, obtains an amplified and filtered intermediate frequency signal and transmits the amplified and filtered intermediate frequency signal to the AD collector;

the difference frequency controller is connected with the processor and the signal transmitting module and is used for difference frequency calculation and difference frequency control, so that the signal transmitting module transmits a first signal and a second signal with frequency difference, wherein the first signal is transmitted to the mixer, and the second signal is transmitted to the power amplifier;

the AD collector is connected with the intermediate frequency amplification filter and the processor, receives the intermediate frequency signal from the intermediate frequency amplification filter, collects the intermediate frequency signal and outputs a digital signal to the processor;

the processor is connected with the power supply module, the AD collector, the difference frequency controller and the communication module, controls the difference frequency controller to enable the signal transmitting module to transmit different types of electromagnetic wave signals and record transmitting time information, acquires and processes and analyzes digital signals output by the AD collector, analyzes and calculates echo time, and outputs a processing result to the display module through the communication module;

According to at least one embodiment of this disclosure, the oil well liquid level measurement device, the third circuit includes:

the signal transmitting module is connected with the frequency mixer, the distributor and the processor and used for generating and transmitting electromagnetic wave signals;

the signal receiving module is connected with the distributor and the mixer, comprises a probe and is used for receiving echo signals and inputting the received echo signals to the mixer;

the signal receiving module receives an echo signal from the waveguide structure through the distributor, and the distributor is one of a coupler circuit and a power divider circuit;

the mixer is connected with the signal transmitting module and the signal receiving module and used for mixing the electromagnetic wave signal transmitted by the signal transmitting module and the echo signal output by the signal receiving module and outputting the mixed signal to the intermediate frequency amplifier;

the intermediate frequency amplifier is connected with the frequency mixer and the AD collector, amplifies the frequency mixing signal output by the frequency mixer and outputs the amplified frequency mixing signal to the AD collector;

the AD collector is connected with the intermediate frequency amplifier and the processor, collects the amplified mixing signals and outputs digital signals to the processor;

According to the oil well liquid level measuring device of at least one embodiment of the present disclosure, the electromagnetic wave signal transmitted by the signal transmitting module is a pulse wave, a wave with fixed frequency and adjustable pulse width, or a frequency-modulated continuous wave.

According to the oil well liquid level measuring device of at least one embodiment of the present disclosure, the display module comprises at least one of a computer, a mobile phone or a radar self-contained display screen, and is used for displaying images and/or adjusting echo signals.

According to the oil well liquid level measuring device of at least one embodiment of the present disclosure, the power supply module is a solar charger and/or an energy storage battery.

According to the oil well liquid level measuring device of at least one embodiment of the present disclosure, the communication technology adopted by the communication module includes at least one of RS232, NB-IOT, Zigbee, and Lora.

According to a further aspect of the present disclosure, there is provided a method for measuring a well fluid level, which is implemented by any one of the well fluid level measuring devices described above, including:

electromagnetic wave signals transmitted by a signal transmitting module of the measuring unit are transmitted to the metal oil pipe through the wave guide structure, and are transmitted vertically downwards by the metal oil pipe so as to generate an echo signal at the liquid level position; and

a signal receiving module of the measuring unit receives echo signals which are vertically and upwards transmitted to the waveguide structure through the metal oil pipe;

the position of the liquid level is determined based on obtaining a time difference between the transmitted signal and the received echo signal, analyzing the number of echo signals, or obtaining a relative position of multiple echo signals.

According to the oil well liquid level measuring method of at least one embodiment of the present disclosure, interference echo signals are removed, the interference echo signals are directly removed through observation of the display module, so that the echo signals required by liquid level measurement are guaranteed to be correct echo signals, or the correct echo signals are directly selected through observation of the display module, and the unselected echo signals are regarded as the interference echo signals to be automatically removed.

The method for measuring the oil well liquid level according to at least one embodiment of the present disclosure comprises a reference echo calibration technology, wherein the reference echo calibration technology utilizes a reference echo to determine the actual transmission speed of an electromagnetic wave signal in a certain area.

According to the oil well liquid level measurement method of at least one embodiment of the present disclosure, the reference echo is a reference echo signal generated by reflecting the transmitted electromagnetic wave signal at each oil pipe joint of known length or at each casing joint of known length.

According to the oil well fluid level measuring method of at least one embodiment of the present disclosure, the actual transmission speed of the electromagnetic wave signal may be determined by obtaining the position of the reference echo and the time when the reference echo is received or measuring the time difference between two or a fixed number of reference echoes.

According to the method for measuring the oil well liquid level, the position of the liquid level is determined based on the reference echo number before the echo signal reflected by the liquid level is received, and the method comprises the following steps: acquiring a vertical distance C between the liquid level measuring device and the top of the metal oil pipe;

obtaining the length L of a single metal oil pipe/casing pipe;

before receiving echo signals reflected by the liquid level, the measuring unit receives N reference echoes, and the liquid level is positioned between the Nth metal oil pipe/casing pipe and the (N +1) th metal oil pipe/casing pipe, wherein N is a natural number more than or equal to 1;

acquiring the time for receiving the Nth reference echo signal as T1;

acquiring the time T2 of receiving the echo signal reflected by the liquid level; and

calculating the vertical distance S from the liquid level to the measuring device, wherein S is (N is L-C) (T2/T1);

and determining the position of the liquid level as S + C.

According to the method for measuring the oil well liquid level, the position of the liquid level is determined based on the relative positions of the echo signals reflected by the liquid level and a plurality of reference echoes, and the method comprises the following steps:

acquiring a distance L0 between adjacent reference echoes through a display module;

obtaining a single metal tubing/casing length L_M；

Acquiring the position of the echo signal reflected by the liquid level in the reference echo through the display module: the echo signal of the liquid level reflection is positioned between the ith reference echo and the (i +1) th reference echo, and the distance from the ith reference echo is D_-aThe distance from the (i +1) th reference echo is D_-bWherein i is a natural number greater than or equal to 1; and

determining the position of the liquid level, wherein the calculation method comprises the following steps: i L_M+(D_-a/L0)*L_MOr (i +1) × L_M-(D_-b/L0)*L_M。

According to the method for measuring the oil well liquid level, the method for determining the liquid level position based on the time difference between the transmitted electromagnetic wave signal and the received echo signal comprises the following steps:

calculating the transmission distance of the echo signal according to the time difference between the transmitted electromagnetic wave signal and the received echo signal acquired by the measuring unit and the actual transmission speed of the signal; and

and determining the liquid level position according to the transmission distance of the echo signal.

The method for measuring the liquid level of the oil well according to at least one embodiment of the present disclosure comprises the following steps: the signal transmitting module generates and transmits a first signal with the frequency f1 and a second signal with the frequency f2 under the action of the difference frequency controller, and obtains the frequency difference delta f as | f1-f2 |;

mixing a liquid level reflection echo signal of a second signal with the frequency f2 with a first signal with the frequency f1, amplifying the mixed signal through an intermediate frequency amplifier, collecting the mixed signal through an AD collector, and measuring to obtain a broadened time difference from signal transmission to signal reception;

calculating an actual time difference from signal transmission to signal reception based on the frequency difference and the broadened time difference;

calculating the transmission distance of the echo signal based on the actual time difference and the actual transmission speed of the signal; and

based on the transmission distance of the echo signal, the liquid level position is determined.

The method for measuring the liquid level of the oil well according to at least one embodiment of the present disclosure comprises the following steps:

the signal transmitting module transmits frequency modulation continuous signals under the action of the processor, the frequency mixer performs frequency mixing on the transmitting signals and echo signals to obtain frequency difference signals, and the frequency difference signals are amplified by the intermediate frequency amplifier and then are obtained by the processor through the AD collector;

obtaining a time difference of the transmission signal and the reception signal based on the frequency difference;

calculating the transmission distance of the echo signal based on the time difference and the actual transmission speed of the signal; and

According to a further aspect of the present disclosure, there is provided a method for measuring a fluid level type of an oil well, the method being characterized in that the fluid level type is measured by any one of the above-mentioned apparatus for measuring a fluid level and a method for measuring a fluid level, and the fluid level type is determined by generating an echo signal difference based on a dielectric constant difference, the method comprising:

acquiring a reflected echo signal; and

the echo morphology is analyzed.

Wherein the echo shape comprises at least one of amplitude, width, front and back edges and phase.

The method of measuring a level type of an oil well according to at least one embodiment of the present disclosure is characterized in that the level type includes an oil level or a water level.

Drawings

The accompanying drawings, which are included to provide a further understanding of the disclosure and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the disclosure and together with the description serve to explain the principles of the disclosure.

FIG. 1 is a schematic view of a fluid level measuring device according to one embodiment of the present disclosure.

Fig. 2 is a schematic diagram of a first circuit configuration according to one embodiment of the present disclosure.

Fig. 3 is a second circuit configuration schematic according to an embodiment of the present disclosure.

Fig. 4 is a third circuit configuration schematic according to an embodiment of the present disclosure.

FIG. 5 is a schematic flow diagram of a method of liquid level measurement according to one embodiment of the present disclosure.

FIG. 6 is a schematic flow diagram of a method of level measurement according to yet another embodiment of the present disclosure.

FIG. 7 is a schematic flow diagram of a method of level measurement according to yet another embodiment of the present disclosure.

FIG. 8 is a schematic flow diagram of a method of level type measurement according to yet another embodiment of the present disclosure.

FIG. 9 is a schematic flow diagram of a method of level measurement according to yet another embodiment of the present disclosure.

FIG. 10 is a schematic flow diagram of a method of level measurement according to yet another embodiment of the present disclosure.

Description of the reference numerals

1000 liquid level measuring device

1001 measurement unit

1002 waveguide structure

1003 ground stage

1004 signal stage

1005 insulator

1006 first seal

1007 handle

1008 switch

1009 baffle

1010 energy consumption structure

1011 second sealing body

1012 to compact the structure.

Detailed Description

The present disclosure will be described in further detail with reference to the drawings and embodiments. It is to be understood that the specific embodiments described herein are for purposes of illustration only and are not to be construed as limitations of the present disclosure. It should be further noted that, for the convenience of description, only the portions relevant to the present disclosure are shown in the drawings.

It should be noted that the embodiments and features of the embodiments in the present disclosure may be combined with each other without conflict. Technical solutions of the present disclosure will be described in detail below with reference to the accompanying drawings in conjunction with embodiments.

Unless otherwise indicated, the illustrated exemplary embodiments/examples are to be understood as providing exemplary features of various details of some ways in which the technical concepts of the present disclosure may be practiced. Accordingly, unless otherwise indicated, features of the various embodiments may be additionally combined, separated, interchanged, and/or rearranged without departing from the technical concept of the present disclosure.

The use of cross-hatching and/or shading in the drawings is generally used to clarify the boundaries between adjacent components. As such, unless otherwise noted, the presence or absence of cross-hatching or shading does not convey or indicate any preference or requirement for a particular material, material property, size, proportion, commonality between the illustrated components and/or any other characteristic, attribute, property, etc., of a component. Further, in the drawings, the size and relative sizes of components may be exaggerated for clarity and/or descriptive purposes. While example embodiments may be practiced differently, the specific process sequence may be performed in a different order than that described. For example, two processes described consecutively may be performed substantially simultaneously or in reverse order to that described. In addition, like reference numerals denote like parts.

When an element is referred to as being "on" or "on," "connected to" or "coupled to" another element, it can be directly on, connected or coupled to the other element or intervening elements may be present. However, when an element is referred to as being "directly on," "directly connected to" or "directly coupled to" another element, there are no intervening elements present. For purposes of this disclosure, the term "connected" may refer to physically, electrically, etc., and may or may not have intermediate components.

The terminology used herein is for the purpose of describing particular embodiments and is not intended to be limiting. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. Furthermore, when the terms "comprises" and/or "comprising" and variations thereof are used in this specification, the presence of stated features, integers, steps, operations, elements, components and/or groups thereof are stated but does not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components and/or groups thereof. It is also noted that, as used herein, the terms "substantially," "about," and other similar terms are used as approximate terms and not as degree terms, and as such, are used to interpret inherent deviations in measured values, calculated values, and/or provided values that would be recognized by one of ordinary skill in the art.

As shown in fig. 1, the liquid level measuring device 1000 emits an electromagnetic wave signal to the metal oil pipe of the oil well, the electromagnetic wave signal is transmitted along the outer surface of the metal oil pipe, the electromagnetic wave signal is reflected back when encountering an oil level or a water level to form an echo signal, the measuring device receives the echo signal, and the position of the oil or the water is calculated by measuring the time difference between the emitted and the echo signal or analyzing the signal information containing the time difference. The measurement device 1000 includes:

a measuring unit 1001 connected to the signal stage 1004 of the waveguide structure 1002 for measuring the liquid level; and the number of the first and second groups,

a waveguide structure 1002, comprising:

a ground stage 1003 connecting the casing of the well;

a signal stage 1004, which is located in the ground stage 1003, has the same extending direction as the ground stage 1003, has one side connected to the measuring unit 1001, can move along the extending direction of the ground stage 1003, can extend to the metal oil pipe from the other side to be connected to the metal oil pipe, receives the electromagnetic wave signal transmitted by the measuring unit 1001, transmits the electromagnetic wave signal to the metal oil pipe, receives the echo, and transmits the echo to the measuring unit 1001; insulators 1005 which are provided between the signal stages 1004 and the ground stages 1003 to insulate the signal stages 1004 from the ground stages 1003, and are provided in plurality and uniformly distributed in the extending direction of the signal stages 1004;

a first sealing body 1006, which is located between the signal stage 1004 and the insulator 1005, and seals the signal stage 1004 and the insulator 1005;

a second sealing body 1011 disposed between the insulator 1005 and the ground 1003 for sealing the ground 1003 and the insulator 1005,

the signal stage 1004 of the waveguide structure 1002 is also movable along the extending direction of the ground stage 1003, and can move away from the metal oil pipe when measurement is not needed.

In addition, the measuring device 1000 further comprises a handle 1007, which is connected to the signal stage 1004 at a side close to the measuring unit 1001 for moving the signal stage 1004 to connect or disconnect the signal stage 1004 with or from the metal tubing.

Also included is a switch 1008, the switch 1008 being used to control whether the signal stage 1004 is movable.

The device further comprises a baffle 1009, wherein the baffle 1009 is connected with the well casing or the grounding stage 1003 and arranged outside the well casing and used for limiting the maximum range of motion of the signal stage 1004 and avoiding the measurement unit 1001 from falling off due to the overlarge moving range distance when the signal stage 1004 moves outwards along the guide pipe.

The liquid level measurement device further comprises a compression structure 1012, wherein the compression structure 1012 ensures that the signal stage 1004 of the waveguide structure 1002 is effectively connected with the metal oil pipe in the liquid level measurement process.

The liquid level measuring device further comprises an energy consumption structure 1010, wherein the energy consumption structure 1010 is arranged above the joint of the signal stage 1004 and the metal oil pipe and used for reducing or eliminating energy reflected back when echo signals are transmitted upwards vertically along the metal oil pipe, so that the echo signals transmitted upwards vertically have no influence on liquid level measurement.

The energy consumption structure 1010 includes a wave-absorbing structure and/or an attenuation structure, and is used for reducing or eliminating energy reflected back when an echo signal is transmitted vertically upwards along the metal oil pipe. Wherein the wave impedance of the waveguide structure 1002 along the signal level direction is unchanged or has no abrupt change.

Wherein the waveguide structure 1002 comprises a coaxial type.

The waveguide structure 1002 is one of a waveguide, a radio frequency cable, or a microwave circuit.

Wherein, the side of the signal stage 1004 connected with the metal oil pipe is concave. The concave surface shape comprises a cylindrical shape, and the cylindrical surface can be well attached to the outer surface of the oil pipe.

The first sealing body 1006 and/or the second sealing body 1011 include a sealing ring and/or a gasket. The first seal 1006 is perpendicular to all cross-sections of the signal level 1004 and has the same shape as all cross-sections of the signal level 1004, ensuring that the signal level 1004 is in close contact with the first seal 1006 without voids to prevent sloshing; and/or the second sealing body 1011 is perpendicular to all the cross sections of the grounding stage 1003, and the shape of the second sealing body is the same as that of all the cross sections of the grounding stage 1003, so that the grounding stage 1003 and the second sealing body 1011 are tightly attached without gaps, and sloshing is prevented.

The measurement unit 1001 includes one of a first circuit, a second circuit, and a third circuit.

Fig. 2 is a first circuit configuration schematic according to at least one embodiment of the present disclosure.

As shown in fig. 2, the first circuit includes:

the signal transmitting module is connected with the distributor and the processor and is used for transmitting the electromagnetic wave signals to the distributor;

the communication module enables the processor to be in communication connection with the display module through the communication module and transmits a processing result of the processor to the display module; and the number of the first and second groups,

Wherein the signal transmitting module and the signal receiving module are connected to a common waveguide structure through a distributor. The electromagnetic wave signal emitted by the signal emission module is coupled to the metal oil pipe through the signal level in the common wave guide structure through the distributor. Echo signals formed by reflection are transmitted to the distributor through the signal level of the common wave guide structure and are coupled to the signal receiving module.

Wherein the signal stage may be a center conductor.

Wherein the ground stage may be an outer tube.

Fig. 3 is a second circuit configuration schematic according to at least one embodiment of the present disclosure.

As shown in fig. 3, the second circuit includes:

the signal transmitting module is connected with the difference frequency controller, the frequency mixer and the power amplifier, transmits a first signal to the frequency mixer and transmits a second signal to the power amplifier, the first signal and the second signal have different frequencies, and the frequency of the first signal and the frequency of the second signal are calculated and controlled through the difference frequency controller;

the signal receiving module is connected with the distributor and the frequency mixer and used for receiving the echo signals transmitted to the distributor from the waveguide structure and transmitting the echo signals to the frequency mixer, and the signal receiving module comprises a probe;

the difference frequency controller is connected with the processor and the signal transmitting module and is used for difference frequency calculation and difference frequency control, so that the signal transmitting module transmits a first signal and a second signal with frequency difference, the first signal is transmitted to the frequency mixer, and the second signal is transmitted to the power amplifier;

the processor is connected with the power supply module, the AD collector, the difference frequency controller and the communication module, controls the difference frequency controller to enable the signal transmitting module to transmit different types of electromagnetic wave signals and record transmitting time information, acquires and processes and analyzes digital signals output by the AD collector, analyzes and calculates echo time, and outputs a processing result through the communication module to be transmitted to the display module;

Fig. 4 is a third circuit configuration schematic according to at least one embodiment of the present disclosure.

As shown in fig. 4, the third circuit includes:

the signal transmitting module is connected with the frequency mixer, the distributor and the processor and is used for transmitting electromagnetic wave signals;

the distributor is connected with the signal transmitting module, the signal receiving module and the waveguide structure, the signal transmitting module transmits the electromagnetic wave signal to the waveguide structure through the distributor, the signal receiving module receives the echo signal from the waveguide structure through the distributor, and the distributor is one of a coupler circuit and a power divider circuit;

and the display module is connected with the processor through the communication module, displays the processing result of the processor and displays the echo signal in the measuring range.

In the two circuit structures shown in fig. 2-3, the electromagnetic wave signal emitted by the signal emitting module is a pulse wave with fixed frequency and adjustable pulse width; in the circuit structure shown in fig. 4, the electromagnetic wave signal transmitted by the signal transmitting module is a frequency modulated continuous wave.

In the above three circuit structures, the display module includes at least one of a computer, a mobile phone or a radar self-contained display screen, and is used for displaying images and/or adjusting echoes. The power supply module is a solar charger and/or an energy storage battery. The power supply module can be a solar charger, adopts a solar wireless charging technology and an energy storage battery, uses a solar panel to convert solar energy into electric energy to be stored in the energy storage battery, and outputs the electric energy to the processor for power supply when the processor needs to be powered. This solar charger collocation energy storage battery of enough capacity, when lasting overcast and rainy day, energy storage battery electric quantity 24 hours uninterrupted power supply can last a journey more than one month, does not worry because of the electric quantity is not enough to lead to unable measuring problem to this solar charger possess intelligent regulation function, can adjust different output voltage and electric current through output adjustable circuit, satisfies the power supply demand. The solar charger has the advantages of environmental protection and convenient installation by reducing cable arrangement. The power supply module can also directly adopt a mode of directly supplying power by the energy storage battery, and when the electric quantity of the energy storage battery arranged on the measuring device is low or the electric quantity is exhausted, the other energy storage battery which is charged up is directly used for replacing.

The communication technology adopted by the communication module comprises at least one of RS232, NB-IOT, Zigbee and Lora.

According to the liquid level measuring method implemented by any oil well liquid level measuring device disclosed by the disclosure, an electromagnetic wave signal transmitted by a signal transmitting module of a measuring unit is transmitted to a metal oil pipe through a wave guide structure and is transmitted vertically downwards by the metal oil pipe so as to generate an echo signal at the liquid level position, a signal receiving module of the measuring unit receives the echo signal transmitted vertically upwards to the wave guide structure through the metal oil pipe, and finally a processor determines the position of the liquid level based on obtaining the time difference between the transmitted signal and the received echo signal, analyzing the number of the echo signals or obtaining the relative positions of a plurality of echo signals.

Wherein, can observe and get rid of through display module and disturb the echo to guarantee that the echo that the measurement liquid level needs is correct echo. All the conditions of the echo signals can be observed through the display module, the correct echo signals can be selected through human intervention, the unselected echo signals are regarded as interference echoes, and automatic elimination is realized; or the human intervention directly selects some echo signals as interference echoes, so as to eliminate the interference echoes, and the rest echo signals are correct echo-back signals.

Wherein the actual transmission speed of the electromagnetic wave signal of a certain area can be determined by using a reference echo calibration technique. The reference echo can be generated at the position of the joint of a metal oil pipe with a known length and also can be generated at the position of the joint of a casing pipe with a known length. The position of the reference echo can be obtained by utilizing the reference echo signal generated by reflecting the transmitted electromagnetic wave signal at the joint of the metal oil pipe or the sleeve pipe and the known length of one oil pipe or sleeve pipe. The transmission speed of the electromagnetic wave signal in different areas can be calculated through the position of the reference echo and the time when the reference echo is received. Or measuring the time difference between two or a fixed number of reference echoes, and knowing the lengths of the two or a fixed number of oil pipes, the transmission speed of the electromagnetic wave signal in the distance can be obtained.

FIG. 5 is a schematic flow diagram of a method for measuring liquid level provided in accordance with at least one embodiment of the present disclosure.

As shown in fig. 5, the liquid level measuring method S100 includes: through any above-mentioned liquid level measurement device, the reference echo number before receiving the liquid level reflection echo confirms the liquid level position, includes:

s102: acquiring a vertical distance C between the liquid level measuring device and the top of the metal oil pipe;

s104: obtaining the length L of a single metal oil pipe/casing pipe;

s106: acquiring time T1 of receiving a reference echo signal, wherein the reference echo is generated by reflecting the transmitted electromagnetic wave signal at the joint of the metal oil pipe or the sleeve pipe;

s108: acquiring the position of the liquid level relative to the metal tubing/casing: before receiving echo signals reflected by the liquid level, the measuring unit receives N reference echo signals, and the liquid level is positioned between the Nth metal oil pipe/casing pipe and the (N +1) th metal oil pipe/casing pipe, wherein N is a natural number which is more than or equal to 1;

s110: acquiring the time T2 of receiving an echo signal formed by liquid level reflection; and the number of the first and second groups,

s112: obtaining the distance S from the liquid level to the measuring system, wherein S is (N is L-C) (T2/T1),

and determining the position of the liquid level as S + C.

FIG. 6 is a schematic flow diagram of a method for measuring liquid level provided in accordance with at least one embodiment of the present disclosure.

As shown in fig. 6, the method S200 for determining a liquid level position based on relative positions of an echo signal reflected by the liquid level and a plurality of reference echoes by the liquid level measuring apparatus includes:

acquiring a distance L0 between adjacent reference echoes through a display module, wherein the reference echoes are generated after the transmitted electromagnetic wave signals are reflected at the joint of the metal oil pipe or the joint of the sleeve;

obtaining the length L of a single metal tubing/casing_M；

Acquiring the position of an echo signal transmitted by the liquid level in a reference echo through a display module: the echo signal emitted by the liquid level is positioned between the ith reference echo and the (i +1) th reference echo, and the distance from the ith reference echo is D_-aThe distance from the (i +1) th reference echo is D_-bWherein i is a natural number greater than or equal to 1; and the number of the first and second groups,

calculating the position S of the liquid level, wherein the calculating method comprises the following steps: s ═ i ═ L_M+(D_-a/L0)*L_MOr S ═ L (i +1) × (L)_M-(D_-b/L0)*L_M。

FIG. 7 is a schematic flow diagram of a method for measuring fluid level provided in accordance with at least one embodiment of the present disclosure.

As shown in fig. 7, the liquid level measuring method S300, which measures the liquid level by the above liquid level measuring device, calculates the liquid level position based on the time difference between the transmitted electromagnetic wave signal and the received echo signal, calculates the transmission distance of the echo signal according to the time difference between the transmitted electromagnetic wave signal and the received echo signal and the actual transmission rate of the signal, and then determines the liquid level position according to the transmission distance of the echo signal, includes:

s302: transmitting a first signal with the frequency f1 and a second signal with the frequency f2, and acquiring a frequency difference delta f ═ f1-f2 |;

s304: mixing a liquid level reflection echo signal of a second signal with the frequency f2 with a first signal with the frequency f1, amplifying the mixed signal through an intermediate frequency amplifier, sampling the mixed signal through an AD collector, and measuring to obtain a broadened time difference from signal transmission to signal reception;

s306: calculating the actual time difference from the transmission of the electromagnetic wave signal to the reception of the echo signal based on the frequency difference and the broadened time difference;

s308: calculating the transmission distance of the electromagnetic wave based on the actual time difference and the electromagnetic wave speed; and the number of the first and second groups,

s310: based on the electromagnetic wave transmission distance, the liquid level position is calculated.

The processor controls the difference frequency controller to enable the signal transmitting module to transmit 2 transmitting signals with the frequency difference deltaf. The frequency of the first transmission signal is f1, the frequency of the second transmission signal is f2, and then Δ f is | f1-f2 |. If the frequency of the reflected echo signal obtained by directly using a simple transmitting and receiving circuit is F, the frequency of the transmitted echo signal obtained by equivalent sampling is Fe ═ F2/Δ F. If the time difference between the transmitted signal and the received reflected echo obtained by directly using a simple transmitting and receiving circuit is T, the signal time difference Te obtained through time broadening is T f 2/delta f, and the transmission time is amplified by f 2/delta f times, so that the measurement difficulty is reduced, and the measurement accuracy is greatly improved. And the second path of transmitting signal is sent to the distributor through the power amplifier, so that the second path of signal is coupled to the oil pipe through the central conductor of the common waveguide structure, and the transmission of the transmitting signal is realized. The reflection echo signal is transmitted to a distributor through a central conductor of a common wave guide structure and coupled to a signal receiving module, the signal receiving module mixes the received reflection signal with a first path of transmitting signal to generate a time broadening signal of the reflection echo signal, the time broadening signal has a large amount of high-frequency components and weak signals, so an amplified and filtered intermediate frequency signal is obtained through an intermediate frequency amplification filter, an AD collector collects the intermediate frequency signal and transmits the intermediate frequency signal to a processor, the processor analyzes and calculates the echo time of the intermediate frequency signal to obtain Te, the time broadening multiple delta f/f2 is calculated according to the frequency difference delta f, the actual time difference T can be obtained as Te x delta f/f2, and the transmission distance of the reflection signal is obtained due to the transmission speed of electromagnetic waves, so the position of the liquid level is determined. The frequency difference Δ f is not fixed and may vary depending on external settings, measured distance, reflected echo information, and other factors. The power amplifier may not be used if the high frequency signal transmitted by the signal transmission module is strong enough.

According to the liquid level measuring method provided by the embodiment, one of two high-frequency transmitting signals with frequency difference and a reflected high-frequency receiving signal are mixed to realize equivalent sampling of pulse echo signals, the original short time difference is widened to realize accurate measurement of the time difference, so that an accurate distance is obtained, and the liquid level measuring precision is effectively improved.

FIG. 8 is a schematic flow diagram of a method for measuring liquid level provided in accordance with at least one embodiment of the present disclosure.

As shown in fig. 8, a liquid level type measuring method S400, which measures a liquid level type by the above liquid level measuring apparatus and measuring method, and determines the liquid level type based on a difference in echo signals generated by a difference in dielectric constants of water and oil, includes:

s402: acquiring a reflected echo signal;

s404: analyzing the echo morphology; and the number of the first and second groups,

s406: determining a level type based on the echo morphology, the echo morphology including at least one of amplitude, width, leading and trailing edges, and phase, the level type including an oil level or a water level.

The oil and water are layered under the oil well, and due to the fact that dielectric constants of the oil and the water are different, electromagnetic waves can generate a reflection signal at an oil layer, then the electromagnetic waves can penetrate through the oil layer, and a reflection signal can be generated at an interface of the oil and the water. Whether the reflected echo is the oil level or the water level is determined by the waveform difference of the echo signal reflected by the oil layer and the echo signal reflected by the water-oil interface. The waveform difference may be amplitude, width, leading and trailing edges, phase, etc. information.

The liquid level type measuring method provided by the embodiment of the disclosure can distinguish the liquid level types, and further can improve the liquid level measuring precision during liquid level measurement.

FIG. 9 is a schematic view of a liquid level measurement method provided in accordance with at least one embodiment of the present disclosure.

As shown in fig. 9, if the liquid level is between the oil pipe 4 and the oil pipe 5, the calculation process is: knowing the vertical distance C between the position where the measuring device is installed and the top of the oil pipe 1 and the length of each oil pipe, the lengths of the first 4 oil pipes are known as L x 4 and L is the length of a single oil pipe, the time T1 when a reference echo generated at the joint of the 4 th oil pipe and the 5 th oil pipe is received and the time T2 when an echo signal reflected by the liquid level is received can be detected, and the distance S between the liquid level and the measuring device can be calculated, because T2/T1 is S/(L x 4-C), T2, T1 and L, C are known, so that the position of the liquid level can be determined.

FIG. 10 is a schematic view of a liquid level measurement method provided in accordance with at least one embodiment of the present disclosure.

As shown in fig. 10, if it is known through the display module that the echo signal reflected by the liquid level is between the reference echo 3 and the reference echo 4, the distance between the echo signal reflected by the liquid level and the reference echo 3 is D3, the distance between the echo signal reflected by the liquid level and the reference echo 4 is D4, the distance between the reference echoes is known as L0, and the actual length of one oil pipe or one casing pipe is L, the position where the liquid level is located is calculated by: S-3L + (D3/L0) L or S-4L- (D4/L0) L.

In the description herein, reference to the description of the terms "one embodiment/implementation," "some embodiments/implementations," "an example," "a specific example," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment/implementation or example is included in at least one embodiment/implementation or example of the present application. In this specification, the schematic representations of the terms described above are not necessarily the same embodiment/mode or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments/modes or examples. Furthermore, the various embodiments/aspects or examples and features of the various embodiments/aspects or examples described in this specification can be combined and combined by one skilled in the art without conflicting therewith.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present application, "plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

It will be understood by those skilled in the art that the foregoing embodiments are merely for clarity of illustration of the disclosure and are not intended to limit the scope of the disclosure. Other variations or modifications may occur to those skilled in the art, based on the foregoing disclosure, and are still within the scope of the present disclosure.

Claims

1. An oil well liquid level measuring device which characterized in that:

the measuring device transmits an electromagnetic wave signal to a metal oil pipe of an oil well, the electromagnetic wave signal is transmitted along the metal oil pipe and reflected back when encountering an oil level or a water level to form an echo signal, the measuring device receives the echo signal, and the position of oil or water is calculated by measuring the time difference between the transmitted and echo signals or analyzing signal information containing the time difference;

preferably, the electromagnetic wave signal is transmitted along the outer surface of the metal oil pipe.

2. A well level measuring device according to claim 1, characterized in that the measuring device comprises:

a measurement unit connected to a signal level of the waveguide structure; and

a waveguide structure, comprising:

a ground stage connected to the casing of the oil well;

the signal stage of the waveguide structure can also move along the extension direction of the grounding stage and can move towards the direction far away from the metal oil pipe when measurement is not needed;

preferably, the measuring device further comprises:

a switch for controlling whether the signal stage is movable; and

the energy consumption structure comprises a wave absorbing structure and/or an attenuation structure;

preferably, the wave impedance of the waveguide structure along the direction of the signal level is unchanged or has no abrupt change, and the waveguide structure comprises a coaxial type;

preferably, the waveguide structure is one of a waveguide, a radio frequency cable and a microwave circuit;

preferably, the insulators are multiple and are uniformly distributed in the extending direction of the signal level;

preferably, one side of the signal stage connected with the metal oil pipe is concave;

preferably, the concave surface comprises a cylindrical shape, and the cylindrical surface can be well attached to the outer surface of the oil pipe;

preferably, the first sealing body comprises a sealing ring and/or a gasket, the first sealing body is perpendicular to the signal level, and the cross section of the sealing body has the same shape as that of the cross section of the signal level and is used for tightly attaching the signal level and the sealing body; and/or the presence of a gas in the gas,

3. A well level measurement device according to claim 2, wherein the measurement unit comprises one of a first circuit, a second circuit or a third circuit, wherein the first circuit comprises:

the display module is connected with the processor through the communication module and displays the processing result of the processor;

the second circuit includes:

the third circuit includes:

preferably, the electromagnetic wave signal transmitted by the signal transmitting module is a pulse wave, a wave with fixed frequency and adjustable pulse width or a frequency-modulated continuous wave;

preferably, the display module comprises at least one of a computer, a mobile phone or a radar self-contained display screen and is used for displaying images and/or adjusting echo signals;

preferably, the power supply module is a solar charger and/or an energy storage battery;

preferably, the communication technology adopted by the communication module comprises at least one of RS232, NB-IOT, Zigbee and Lora.

4. A method for measuring a well fluid level, which is implemented by the well fluid level measuring apparatus according to any one of claims 1 to 3, comprising:

determining a position of the liquid level based on obtaining a time difference between the transmitted signal and the received echo signal, analyzing a number of the echo signals, or obtaining a relative position of a plurality of echo signals;

preferably, the method further comprises rejecting interference echo signals, and directly rejecting the interference echo signals through observation of a display module so as to ensure that echo signals required by liquid level measurement are correct echo signals, or directly selecting correct echo signals through observation of the display module, wherein unselected echo signals are regarded as interference echo signals and automatically rejected;

preferably, a reference echo calibration technology is further included, and the reference echo calibration technology utilizes a reference echo to determine the actual transmission speed of the electromagnetic wave signal in a certain area;

preferably, the reference echo is a reference echo signal generated by reflecting the transmitted electromagnetic wave signal at each oil pipe joint or each casing joint with a known length;

preferably, the actual transmission speed of the electromagnetic wave signal may be determined by obtaining the position of the reference echo and the time at which the reference echo is received or measuring the time difference between two or a fixed number of reference echoes.

5. A method for measuring a fluid level in a well according to claim 4, wherein determining the fluid level position based on a reference echo number before receiving the echo signal reflected by the fluid level comprises: acquiring a vertical distance C between the liquid level measuring device and the top of the metal oil pipe;

obtaining the length L of a single metal oil pipe/casing pipe;

acquiring the time for receiving the Nth reference echo signal as T1;

and determining the position of the liquid level as S + C.

6. A method of measuring a fluid level in a well according to claim 4, wherein determining the fluid level position based on the relative position of the echo signal of the fluid level reflection and a plurality of reference echoes comprises:

obtaining a single metal tubing/casing length L_M；

7. A method of measuring a well fluid level according to claim 4, wherein determining a fluid level position based on a time difference between a transmitted electromagnetic wave signal and a received echo signal comprises:

8. The method of measuring the fluid level in an oil well according to claim 7, comprising: the signal transmitting module generates and transmits a first signal with the frequency f1 and a second signal with the frequency f2 under the action of the difference frequency controller, and obtains the frequency difference delta f as | f1-f2 |;

9. The method of measuring the fluid level in an oil well according to claim 7, comprising:

10. A method for measuring a fluid level type of a well by the apparatus for measuring a fluid level and the method for measuring a fluid level according to claims 1 to 9, wherein the method for determining a fluid level type by generating an echo signal difference based on a difference in dielectric constant comprises:

acquiring a reflected echo signal; and

analyzing the echo morphology;

wherein the echo form comprises at least one of amplitude, width, front and back edges and phase;

preferably, the level type includes an oil level or a water level.