CN114622871B

CN114622871B - Pumping unit control system and method

Info

Publication number: CN114622871B
Application number: CN202011448232.5A
Authority: CN
Inventors: 王普军; 李士澜; 刘建林; 徐立鑫; 张令利; 王翠利
Original assignee: Petrochina Co Ltd
Current assignee: Petrochina Co Ltd
Priority date: 2020-12-09
Filing date: 2020-12-09
Publication date: 2023-10-27
Anticipated expiration: 2040-12-09
Also published as: CN114622871A

Abstract

The embodiment of the application discloses a control system and a control method for an oil pumping unit, belonging to the field of petroleum engineering. The system comprises an oil pumping unit, a control cabinet and a first monitoring device; the pumping unit comprises a rope hanger, a square clip and a pumping rod; the first monitoring device is fixed on the square clamp and comprises a first distance sensor, a first monitoring module and a first communication module, wherein the first distance sensor is positioned on the lower surface of the square clamp; the first distance sensor is used for acquiring a first distance between the first distance sensor and the rope hanger and sending the first distance to the first monitoring module; the first monitoring module is used for receiving the first distance, and sending a braking signal to the first communication module if the first distance exceeds a first threshold value; the first communication module is used for receiving the braking signal and forwarding the braking signal to the control cabinet; the control cabinet is used for receiving the braking signal and controlling the pumping unit to stop running according to the braking signal, so that the damage of the pumping unit caused by the failure of the pumping unit to the pumping unit is reduced, and the rejection rate of the pumping unit and the petroleum exploitation cost are reduced.

Description

Pumping unit control system and method

Technical Field

The embodiment of the application relates to the field of petroleum engineering, in particular to a pumping unit control system and method.

Background

The pumping unit is one kind of petroleum exploitation equipment, and is connected via pumping rod to the pumping unit in well bore to control the pumping rod to move up and down and drive the pumping unit to pump petroleum from underground to ground. In the use process of the pumping unit, the pumping unit can be failed due to natural conditions, irregular installation, wax precipitation of an oil well or the like, and if the pumping unit fails, the pumping unit still works continuously, and the whole pumping unit can be scrapped.

At present, when the pumping unit operates, an operator can monitor the pumping unit, and once the pumping unit is found to be faulty, the operator immediately controls the pumping unit to stop operating. However, after the pumping unit fails, the pumping unit is greatly damaged in a short time, so that even if operators on duty find the pumping unit fails in time, the operators are difficult to prevent the damage in time.

Disclosure of Invention

The embodiment of the application provides a control system and a control method for an oil pumping unit, which can brake the oil pumping unit in time when the oil pumping unit fails, and avoid great damage to the oil pumping unit. The technical scheme is as follows:

in one aspect, a pumping unit control system is provided, the system comprising a pumping unit, a control cabinet and a first monitoring device; the control cabinet is electrically connected with the oil pumping unit;

The pumping unit comprises a rope hanger, a square clamp and a sucker rod, wherein the square clamp is positioned above the rope hanger and fixedly connected with the sucker rod, and the sucker rod passes through the center of the rope hanger;

when the pumping unit works, the rope hanger drives the square clamp to move up and down, and the square clamp drives the pumping rod to move up and down;

the first monitoring device is fixed on the square clamp and comprises a first distance sensor, a first monitoring module and a first communication module, wherein the first distance sensor is positioned on the lower surface of the square clamp, the first monitoring module is electrically connected with the first distance sensor and the first communication module respectively, and the first communication module is in wireless communication connection with the control cabinet;

the first distance sensor is used for acquiring a first distance between the first distance sensor and the rope hanger and sending the first distance to the first monitoring module;

the first monitoring module is used for receiving the first distance, and sending a braking signal to the first communication module if the first distance exceeds a first threshold value, wherein the first threshold value is the distance between the first distance sensor and the rope hanger when the pumping unit normally operates;

The first communication module is used for receiving the braking signal and forwarding the braking signal to the control cabinet;

the control cabinet is used for receiving the braking signal and controlling the pumping unit to stop running according to the braking signal.

In one possible implementation manner, the system further comprises an alarm, and the control cabinet is electrically connected with the alarm or establishes a wireless communication connection with the alarm;

the first monitoring module is further used for determining fault information of the pumping unit according to the first distance and sending the fault information to the first communication module;

the first communication module is also used for receiving the fault information and forwarding the fault information to the control cabinet;

the control cabinet is also used for receiving the fault information, determining alarm information matched with the fault information and sending the alarm information to the alarm;

the alarm is used for receiving the alarm information and sending the alarm information.

In one possible implementation manner, the first monitoring module is configured to obtain first fault information if the first distance exceeds the first threshold and does not exceed a second threshold, and send the first fault information to the first communication module, where the first fault information indicates that a sucker rod of the pumping unit is broken;

The first monitoring module is used for acquiring second fault information if the first distance exceeds the second threshold value and does not exceed a third threshold value, and sending the second fault information to the first communication module, wherein the second fault information indicates that the sucker rod is blocked by an oil well;

the first monitoring module is used for acquiring third fault information if the first distance exceeds the third threshold value, and sending the third fault information to the first communication module, wherein the third fault information indicates that the rope hanger falls off;

wherein the first threshold, the second threshold, and the third threshold are sequentially incremented.

In one possible implementation, the first monitoring device further includes a second distance sensor electrically connected to the first monitoring module;

the second distance sensor is positioned on the upper surface of the square clamp, and faces the sucker rod; or the second distance sensor comprises a sensor main body and a target component, wherein the sensor main body is used for detecting the position of the target component, the sensor main body is positioned on the upper surface of the square clamp, and the target component is positioned on the sucker rod and is opposite to the sensor main body;

The second distance sensor is used for acquiring a second distance between the second distance sensor and the sucker rod and sending the second distance to the first monitoring module;

the first monitoring module is further configured to receive the second distance, and if the second distance is different from a reference distance, send the braking signal to the first communication module, where the reference distance is a distance between the second distance sensor and the sucker rod when the square clip is fixedly connected with the sucker rod.

In one possible implementation manner, the first monitoring device further comprises a motion sensor, wherein the motion sensor is located at any position of the square clamp, and the motion sensor is electrically connected with the first monitoring module;

the motion sensor is used for detecting the state of the square clamp and sending the state to the first monitoring module, and the state indicates that the square clamp is in a motion state or in a static state;

the first monitoring module is used for receiving the state, and if the state indicates that the square clamp is in a static state, the braking signal is sent to the first communication module.

In one possible implementation manner, the oil pumping unit further comprises a reduction gearbox, a crank and a connecting rod, wherein a first end of the crank is hinged with the reduction gearbox, a second end of the crank comprises a crank pin, the connecting rod is sleeved on the crank pin, and the crank pin is perpendicular to a main body of the crank and a main body of the connecting rod;

When the oil pumping unit works, the reduction gearbox drives the crank to rotate around the first end, and the crank drives the connecting rod to rotate around the second end;

the system also comprises a second monitoring device, wherein the second monitoring device is fixed on the crank, the second monitoring device comprises a third distance sensor, a second monitoring module and a second communication module, the second monitoring module is respectively and electrically connected with the third distance sensor and the second communication module, and the second communication module is in wireless communication connection with the control cabinet;

the third distance sensor is used for acquiring a third distance between the third distance sensor and the connecting rod and sending the third distance to the second monitoring module;

the second monitoring module is used for receiving the third distance, and sending the braking signal to the second communication module if the third distance exceeds a fourth threshold value, wherein the fourth threshold value is the distance between the third distance sensor and the connecting rod when the crank is normally connected with the connecting rod.

In one possible implementation manner, the oil pumping unit further comprises a horsehead and a steel wire rope, one end of the steel wire rope is fixedly connected with the rope hanger, the other end of the steel wire rope is fixedly connected with the horsehead, and the rope hanger is positioned below the horsehead;

The system further comprises a third monitoring device which is fixed at the wellhead of the oil well, wherein the wellhead is positioned below the rope hanger;

the third monitoring device comprises a fourth distance sensor, a third monitoring module and a third communication module, the fourth distance sensor is positioned on the upper surface of the wellhead and faces the rope hanger, the third monitoring module is respectively and electrically connected with the fourth distance sensor and the third communication module, and the third communication module is in wireless communication connection with the control cabinet;

the fourth distance sensor is used for acquiring a fourth distance between the fourth distance sensor and the rope hanger and sending the fourth distance to the third monitoring module;

the third monitoring module is configured to receive the fourth distance, and if the fourth distance is smaller than a fifth threshold, send the braking signal to the third communication module, where the fifth threshold is a minimum distance between the fourth distance sensor and the rope hanger in an up-and-down movement process of the rope hanger when the steel wire rope is not deformed.

In one possible implementation manner, the oil pumping unit further comprises a horsehead and a steel wire rope, one end of the steel wire rope is fixedly connected with the rope hanger, the other end of the steel wire rope is fixedly connected with the horsehead, and the rope hanger is suspended below the horsehead;

The system further comprises a fourth monitoring device, wherein the fourth monitoring device is fixed on the rope hanger and comprises an ultrasonic sensor, a fourth monitoring module and a fourth communication module, the ultrasonic sensor is positioned at the joint of the rope hanger and the steel wire rope, the fourth monitoring module is respectively and electrically connected with the ultrasonic sensor and the fourth communication module, and the fourth communication module is in wireless communication connection with the control cabinet;

the ultrasonic sensor is used for detecting an ultrasonic reflection signal and sending the ultrasonic reflection signal to the fourth monitoring module;

the fourth monitoring module is used for receiving the ultrasonic reflection signal, and sending the braking signal to the fourth communication module if the ultrasonic reflection signal indicates that the object at the joint has a crack;

the fourth communication module is used for receiving the braking signal and forwarding the braking signal to the control cabinet.

On the other hand, the control method of the pumping unit is provided and applied to a pumping unit control system, and the system comprises the pumping unit, a control cabinet and a first monitoring device; the control cabinet is electrically connected with the oil pumping unit;

The pumping unit comprises a rope hanger, a square clamp and a pumping rod, wherein the pumping rod penetrates through the center of the rope hanger, the square clamp is positioned above the rope hanger, and the square clamp is fixedly connected with the pumping rod;

the first monitoring device is fixed on the square clamp and comprises a first distance sensor, a first monitoring module and a first communication module, the first monitoring module is respectively and electrically connected with the first distance sensor and the first communication module, and the first communication module is in wireless communication connection with the control cabinet; the method comprises the following steps:

the first distance sensor obtains a first distance between the first distance sensor and the rope hanger, and sends the first distance to the first monitoring module;

the first monitoring module receives the first distance, and if the first distance exceeds a first threshold, a braking signal is sent to the first communication module, wherein the first threshold is the distance between the first distance sensor and the rope hanger when the pumping unit normally operates;

The first communication module receives the braking signal and forwards the braking signal to the control cabinet;

and the control cabinet receives the braking signal and controls the pumping unit to stop running according to the braking signal.

In one possible implementation manner, the system further comprises an alarm, and the control cabinet is electrically connected with the alarm or establishes a wireless communication connection with the alarm; the method further comprises the steps of:

the first monitoring module determines fault information of the pumping unit according to the first distance and sends the fault information to the first communication module;

the first communication module receives the fault information and forwards the fault information to the control cabinet;

the control cabinet receives the fault information, determines alarm information matched with the fault information and sends the alarm information to the alarm;

the alarm receives the alarm information and sends out the alarm information.

In one possible implementation manner, if the first distance exceeds the first threshold value and does not exceed the second threshold value, the first monitoring module obtains first fault information, and sends the first fault information to the first communication module, wherein the first fault information indicates that a sucker rod of the pumping unit is broken;

If the first distance exceeds the second threshold value and does not exceed the third threshold value, the first monitoring module acquires second fault information, and sends the second fault information to the first communication module, wherein the second fault information indicates that the sucker rod is blocked by an oil well;

if the first distance exceeds the third threshold value, the first monitoring module acquires third fault information, and sends the third fault information to the first communication module, wherein the third fault information indicates that the rope hanger falls off;

The second distance sensor obtains a second distance between the second distance sensor and the sucker rod, and sends the second distance to the first monitoring module;

the first monitoring module receives the second distance, and if the second distance is different from a reference distance, the first monitoring module sends the braking signal to the first communication module, wherein the reference distance is the distance between the second distance sensor and the sucker rod when the square clamp is fixedly connected with the sucker rod.

the motion sensor detects the state of the square clamp and sends the state to the first monitoring module, and the state indicates that the square clamp is in a motion state or in a static state;

the first monitoring module receives the state, and if the state indicates that the square clamp is in a static state, the first monitoring module sends the braking signal to the first communication module.

the third distance sensor acquires a third distance between the third distance sensor and the connecting rod, and sends the third distance to the second monitoring module;

the second monitoring module receives the third distance, and if the third distance exceeds a fourth threshold, the second monitoring module sends the braking signal to the second communication module, wherein the fourth threshold is the distance between the third distance sensor and the connecting rod when the crank is normally connected with the connecting rod.

the fourth distance sensor obtains a fourth distance between the fourth distance sensor and the rope hanger, and sends the fourth distance to the third monitoring module;

and the third monitoring module receives the fourth distance, and if the fourth distance is smaller than a fifth threshold value, the third monitoring module sends the braking signal to the third communication module, wherein the fifth threshold value is the minimum distance between the fourth distance sensor and the rope hanger in the up-and-down movement process of the rope hanger when the steel wire rope is not deformed.

the ultrasonic sensor detects an ultrasonic reflected signal and sends the ultrasonic reflected signal to the fourth monitoring module;

the fourth monitoring module receives the ultrasonic reflection signal, and if the ultrasonic reflection signal indicates that the object at the joint has a crack, the fourth monitoring module sends the braking signal to the fourth communication module;

and the fourth communication module receives the braking signal and forwards the braking signal to the control cabinet.

The technical scheme provided by the embodiment of the application has the beneficial effects that at least:

according to the pumping unit control system and the pumping unit control method, when various faults occur in the pumping unit, the square clamp and the rope hanger are not synchronous, if the square clamp and the rope hanger are not synchronous, the pumping unit can be greatly damaged if the pumping unit continues to work, and therefore the monitoring device is arranged on the square clamp to monitor the distance between the square clamp and the rope hanger, and when the square clamp and the rope hanger are not synchronous, the pumping unit is immediately braked by the control cabinet, and because the braking is timely, damage to the pumping unit is reduced, and the rejection rate of the pumping unit and the petroleum exploitation cost are reduced.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the description of the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic structural diagram of a pumping unit control system according to an embodiment of the present application;

FIG. 2 is a schematic diagram of another pumping unit control system according to an embodiment of the present application;

fig. 3 is a flowchart of a control method of an oil pumping unit according to an embodiment of the present application.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the embodiments of the present application more apparent, the following detailed description of the embodiments of the present application will be given with reference to the accompanying drawings.

It is to be understood that the terms "first," "second," and the like, as used herein, may be used to describe various concepts, but are not limited by these terms unless otherwise specified. These terms are only used to distinguish one concept from another. For example, a first distance sensor may be referred to as a second distance sensor and a second distance sensor may be referred to as a first distance sensor without departing from the scope of the present application.

Fig. 1 is a schematic structural diagram of a pumping unit control system according to an embodiment of the present application, and as shown in fig. 1, the system includes a pumping unit 1, a control cabinet 2, and a first monitoring device 3, where the control cabinet 2 is electrically connected with the pumping unit 1.

The pumping unit 1 is an oil exploitation device, and the pumping unit 1 provided by the embodiment of the application can be any pumping unit, for example, the pumping unit 1 is a beam pumping unit, a beam-free pumping unit, a crank-link pumping unit, a belt pumping unit and the like, and the embodiment of the application does not limit the pumping unit 1. The pumping unit 1 comprises a rope hanger 101, a square clamp 102 and a pumping rod 103, wherein the square clamp 102 is positioned above the rope hanger 101, the square clamp 102 is fixedly connected with the pumping rod 103, and the pumping rod 103 passes through the center of the rope hanger 101.

The center of the rope hanger 101 has a sucker rod through hole penetrating the upper and lower surfaces of the rope hanger, through which the sucker rod 103 passes. The size of the square clamp 102 is larger than the size of the sucker rod through hole, and the sucker rod can not slide from the upper side of the rope hanger 101 to the lower side of the rope hanger 101 through the sucker rod through hole, so the sucker rod 103 can not slide from the sucker rod through hole through fixedly connecting the square clamp 102 with the sucker rod 103, and the fixing of the sucker rod 102 is realized.

The square clip 102 and the sucker rod 102 may be connected by any method, for example, a snap connection. Alternatively, after the square clip 102 is engaged, it is fastened to the sucker rod 103 by a bolt.

When the pumping unit 1 works, the rope hanger 101 drives the square clamp 102 to move up and down, and the square clamp 102 drives the pumping rod 103 to move up and down. For example, when the rope hanger 101 moves upward, the rope hanger 101 applies an upward force to the square clip 102, so that the square clip 102 moves upward along with the rope hanger, and the square clip 102 is fixedly connected with the sucker rod 103, so that the square clip 102 drives the sucker rod 103 to move upward when moving upward. When the rope hanger 101 moves downwards, the rope hanger 101 no longer applies downward force to the square clamp 102, and the square clamp 102 and the sucker rod 103 can freely fall under the influence of gravity and move downwards along with the rope hanger 101.

The first monitoring device 3 is a device for monitoring whether the pumping unit 1 is faulty or not, and optionally, the first monitoring device 3 is fixed at a position on the pumping unit 1 where the fault is likely to occur, so that the first monitoring device timely monitors whether the pumping unit 1 is faulty or not.

Because the rope hanger 101 falls off, the sucker rod 103 breaks, the oil well is waxed, etc. may cause the rope hanger 101 to be out of sync with the square clip 102, and the rope hanger 101 is out of sync with the square clip 102 may cause the problem of the pumping unit being on shelf, etc. to cause serious damage to the pumping unit, in the embodiment of the application, the first monitoring device 3 is fixed on the square clip 102, so as to monitor whether the rope hanger 101 is in sync with the square clip 102.

The first monitoring device includes a first distance sensor 301, a first monitoring module 302 and a first communication module 303, where the first distance sensor 301 is located on the lower surface of the square clip 102, the first monitoring module 302 is electrically connected with the first distance sensor 301 and the first communication module 303, and the first communication module 303 establishes a wireless communication connection with the control cabinet 2.

The first distance sensor 301 user obtains a first distance from the rope hanger 101, and sends the first distance to the first monitoring module 302; the first monitoring module 302 receives the first distance, and if the first distance exceeds a first threshold, sends a braking signal to the first communication module 303, wherein the first threshold is the distance between the first distance sensor 301 and the rope hanger 101 when the pumping unit 1 is in normal operation; the first communication module 303 is configured to receive a braking signal, and forward the braking signal to the control cabinet 2; the control cabinet 2 is used for receiving the braking signal and controlling the pumping unit 1 to stop operating according to the braking signal.

The brake signal may be regarded as an instruction for controlling the pumping unit 1 to stop operating, and the control cabinet 2 may immediately control the pumping unit 1 to stop operating after receiving the brake signal.

If the first distance exceeds the first threshold, it indicates that the rope hanger 101 and the square clamp 102 are not synchronous, that is, a gap exists between the rope hanger 101 and the square clamp 102, the reason for the gap may be that the sucker rod 103 breaks, the rope hanger 101 falls off, the oil well is waxed, etc., but no matter what reason for the gap exists, a large fault may occur in the pumping unit 1, for example, after the oil well is waxed, the sucker rod 103 is blocked in the oil well and cannot move up and down, at this time, when the rope hanger 101 moves downwards, the sucker rod 103 and the square clamp 102 cannot fall down even under the action of gravity, so that a gap exists between the rope hanger 101 and the square clamp 102, and when the rope hanger 101 moves upwards, the rope hanger 101 collides with the square clamp located above the rope hanger 101, so that the rope hanger 101 is damaged or the square clamp 102 is damaged.

Because the pumping unit 1 may have a larger fault no matter what the reason of the gap is, in the embodiment of the present application, after the gap is determined between the rope hanger 101 and the square clip 102, the pumping unit 1 is directly controlled to stop running.

The first communication module 303 establishes a wireless communication connection with the control cabinet 2, and optionally, a wireless short-distance communication connection is established between the first communication device 303 and the control cabinet 2, where the wireless short-distance communication connection may be any wireless short-distance communication connection such as a bluetooth connection, a near field communication connection (NFC, near Field Communication), a Wi-Fi (Wireless Fidelity, wireless network) connection, and the like. For example, a bluetooth connection is established between the first communication module 303 and the control cabinet 2, and then the first communication module 303 is a bluetooth module, and the control cabinet 2 also includes a bluetooth module, and the first communication module 303 is connected with the bluetooth module in the control cabinet 2 in a pairing manner, so that a wireless communication connection between the first communication module 303 and the control cabinet 2 is established. Optionally, the first communication module 303 is an antenna module, the control cabinet 2 also includes an antenna module, the antenna module in the first monitoring device 3 sends out a braking signal, and after the antenna module in the control cabinet 2 detects the braking signal, the control cabinet 2 controls the pumping unit 1 to stop running.

The first distance sensor 301 is any sensor capable of determining a distance, for example, an infrared sensor, an ultrasonic sensor, a magnet sensor, or a pressure sensor. The type of the first distance sensor 301 is not limited in the embodiment of the present application.

For example, the first distance sensor 301 is an infrared sensor that is located on the lower surface of the square clip 102 and emits light toward the tether 101, and the light is directed toward the tether 101 and reflected back to the infrared sensor by the tether 101, and the infrared sensor determines a first distance between the infrared sensor and the tether 101 according to the emission time, the receiving time, and the propagation speed of the light.

As another example, the first distance sensor 301 is a magnetic sensor, and the magnetic sensor includes a sensor body and a magnetic sheet, the sensor body is located on the lower surface of the square clip 102, the magnetic sheet is located on the upper surface of the rope hanger 101, and the sensor body determines the position of the magnetic sheet through the detected magnetic force, that is, determines the distance between the magnetic sheet and the sensor body, and the distance between the magnetic sheet and the sensor body corresponds to the distance between the square clip 102 and the rope hanger 101.

According to the pumping unit control system provided by the embodiment of the application, as the square clamp and the rope hanger are not synchronous when the pumping unit has various faults, if the square clamp and the rope hanger are not synchronous, the pumping unit is greatly damaged when the pumping unit continues to work, so that the monitoring device is arranged on the square clamp to monitor the distance between the square clamp and the rope hanger, and when the square clamp and the rope hanger are not synchronous, the pumping unit is immediately braked by the control cabinet, and the damage to the pumping unit is reduced due to timely braking, and the rejection rate of the pumping unit and the cost of petroleum exploitation are reduced.

In one possible implementation, the system further comprises an alarm 4. After the pumping unit 1 is stopped, a technician is required to maintain the pumping unit 1 in order to solve the malfunction of the pumping unit 1 so that the pumping unit 1 can be normally operated. Optionally, the control cabinet 2 is electrically connected with the alarm 4 or establishes a wireless communication connection, so that after the pumping unit 1 is controlled to stop running, the control cabinet 2 can also send an alarm signal to the alarm 4 to enable the alarm 4 to alarm. The alarm 4 may be installed in the control cabinet 2, or may be installed at any position outside the control cabinet 2, and the position of the alarm 4 is not limited in the embodiment of the present application.

Optionally, the alarm 4 is electrically connected to the first monitoring device 3 or a wireless communication connection is established, for example, the alarm 4 is electrically connected to the first monitoring module 302, and when the first monitoring module 302 sends a brake signal to the first communication module 303, the first monitoring module 300 may also send an alarm signal to the alarm 4 to make the alarm 4 alarm. Alternatively, the alarm 4 establishes a wireless communication connection with the first communication module 303, the first monitoring module 302 is configured to receive the first distance, and if the first distance exceeds the first threshold value, send a braking signal and an alarm signal to the first communication module 303, and the first communication module 303 is configured to forward the braking signal to the control cabinet 2 and forward the alarm signal to the alarm 4.

Optionally, the braking signal carries the device identifier of the control cabinet 2, and the alarm signal carries the device identifier of the alarm 4, so that the first communication module 303 can accurately forward the signal to the corresponding device.

The alarm 4 may be fixed in the first monitoring device 3 or in the vicinity of the first monitoring device 3.

In addition, in the embodiment of the present application, after the control cabinet 2 controls the pumping unit 1 to stop running, a technician is required to solve the failure of the pumping unit 1 in time, so that the pumping unit 1 works normally. In order to check the location or cause of the failure of the pumping unit 1, the technician may need to perform a complete inspection of the entire pumping unit 1, resulting in a lower efficiency of the technician in maintaining the pumping unit 1.

In another embodiment of the present application, there is further provided an alarm 4 capable of indicating a failure of the pumping unit, in a possible implementation manner, the control cabinet 2 is electrically connected to the alarm 4 or a wireless communication connection is established, the first monitoring module 302 is configured to determine failure information of the pumping unit 1 according to the first distance, and send the failure information to the first communication module 303; the first communication module 303 is further configured to receive fault information, forward the fault information to the control cabinet 2, and the control cabinet 2 is further configured to receive the fault information, determine alarm information matched with the fault information, and send the alarm information to the alarm 4; the alarm 4 is used for receiving the alarm information and sending out the alarm information.

The alarm information corresponding to the different fault information is different, so that a technician can know the specific fault of the pumping unit 1 according to the alarm information sent by the alarm 4, and the pumping unit 1 can be overhauled quickly. Optionally, the alarm information is a voice information, for example, the voice content of the voice information is that the pumping unit 1 has a fault, for example, when the pumping rod 103 of the pumping unit 1 breaks, the alarm information is "the pumping rod breaks".

The degree of asynchronization of the rope hanger 101 and the square clamp 102 is different when the pumping unit 1 fails, for example, when the pumping rod 103 breaks, a small gap between the rope hanger 101 and the square clamp 102 may occur due to abrupt change of the gravity of the square clamp 102 and the pumping rod 103, and the gap may disappear soon after occurrence; when the sucker rod 103 is blocked by an oil well, the square clamp 102 and the sucker rod 103 are fixed, a larger distance is generated between the falling of the rope hanger 101 and the square clamp 102, but the rope hanger 101 rises after falling, so that the distance between the square clamp 102 and the rope hanger 101 does not exceed the distance between the highest point and the lowest point when the rope hanger 101 moves up and down; when the hanger 101 is detached, a large distance is generated between the square clip 102 and the hanger 101, and even the first distance sensor 301 on the square clip 102 cannot detect the position of the hanger 101.

In one possible implementation, the first monitoring module 302 is configured to obtain first fault information if the first distance exceeds the first threshold and does not exceed the second threshold, and send the first fault information to the first communication module 303, where the first fault information indicates that the sucker rod 103 of the pumping unit 1 is broken; the first monitoring module 302 is configured to obtain second fault information if the first distance exceeds the second threshold and does not exceed the third threshold, and send the second fault information to the first communication module 303, where the second fault information indicates that the sucker rod 103 is blocked by the oil well; the first monitoring module 302 is configured to obtain third fault information if the first distance exceeds a third threshold, and send the third fault information to the first communication module, where the third fault information indicates that the rope hanger 101 is detached. Wherein the first threshold, the second threshold and the third threshold are sequentially incremented.

It should be noted that, in the above embodiment, the alarm process of the alarm 4 is described by taking the example that the alarm 4 is electrically connected to the control cabinet 2 or a wireless communication connection is established, and the alarm 4 is indicated by the control cabinet 2 to send alarm information, and in another embodiment, the alarm 4 may also be electrically connected to the first monitoring device 3 or a wireless communication connection is established, and the alarm 4 is controlled by the first monitoring device 3 to send alarm information.

In one possible implementation, the alarm 4 is electrically connected to the first monitoring device 3 or a wireless communication connection is established. The first monitoring module 302 is further configured to determine fault information of the pumping unit 1 according to the first distance, obtain alarm information matched with the fault information, send the alarm information to the alarm 4, and send the alarm information after the alarm 4 receives the alarm information.

Or, the first monitoring module 302 is further configured to determine fault information of the pumping unit 1 according to the first distance, obtain alarm information matched with the fault information, and send the alarm information to the first communication module 303; the first communication module 303 forwards the alarm information to the alarm 4; the alarm 4 is used for receiving the alarm information and sending out the alarm information.

In one possible implementation, the first monitoring device further includes a second distance sensor 304 electrically connected to the first monitoring module 302.

The second distance sensor 304 is used to monitor the sucker rod 103 to determine whether the sucker rod 103 is loose relative to the square clamp 102 or whether the sucker rod 103 is falling out of the square clamp 102. The second distance sensor 304 is located on the upper surface of the square clip 102, and the second distance sensor 304 faces the sucker rod 103; alternatively, the second distance sensor 304 includes a sensor body for detecting a position of a target member, the sensor body being located on an upper surface of the square clip 102, and the target member being located on the sucker rod 103 and facing the sensor body.

The second distance sensor 304 is configured to obtain a second distance from the sucker rod 103 and send the second distance to the first monitoring module 302. For example, the second distance sensor 304 is an infrared sensor, the infrared sensor is located on the upper surface of the square clip, the infrared sensor faces the sucker rod 103, the infrared sensor emits light, the light is emitted to the sucker rod 103, the light is reflected back to the infrared sensor through the sucker rod 103, and the infrared sensor determines the second distance between the infrared sensor and the sucker rod 103 according to the emitting time, the receiving time and the propagation speed of the light.

For another example, the second distance sensor 304 is a magnet sensor that includes a sensor body and a target component that is a magnetic sheet, and the sensor body determines the position of the magnetic sheet, that is, the distance between the magnetic sheet and the sensor body, by the detected magnetic force.

The second distance sensor 304 is any sensor capable of determining a distance, for example, an infrared sensor, an ultrasonic sensor, a magnet sensor, or a pressure sensor. The type of the second distance sensor 304 is not limited in the embodiment of the present application.

In one possible implementation, the first monitoring device 3 further includes a motion sensor 305, the motion sensor 305 being located at any position of the square clip 102, the motion sensor 305 being electrically connected to the first monitoring module 302. The motion sensor 305 is a sensor for detecting whether the square clip 102 is in a motion state, and the motion sensor 305 is only required to be fixed on the square clip 102, so that the motion sensor 305 moves along with the movement of the square clip 102, and the motion sensor 305 can be fixed at any position on the square clip 102.

The motion sensor 306 is configured to detect a state of the square clamp 102, and send the state to the first monitoring module 302, where the state indicates that the square clamp 102 is in a moving state or in a stationary state; the first monitoring module 302 is configured to receive the status, and if the status indicates that the square clip 102 is in a static state, send a brake signal to the first communication module 303.

It should be noted that, during the application process, the square clip 102 is in a static state, either the pumping unit 1 is not operated or the pumping unit 1 fails, and when the pumping unit 1 is not operated, the pumping unit 1 does not need to be monitored, optionally, when the pumping unit 1 is operated, the first monitoring device 3 is started to detect the pumping unit 1, and when the pumping unit 1 is not operated, the first monitoring device 3 is also not operated. Thus, when the motion sensor detects that the square clamp 102 is in a static state, the pumping unit 1 can be determined to be in fault.

As shown in fig. 2, in one possible implementation, the pumping unit 1 further includes a reduction gearbox 104, a crank 105, and a connecting rod 106, a first end of the crank 105 is hinged with the reduction gearbox 104, a second end of the crank 105 includes a crank pin, the connecting rod 106 is sleeved on the crank pin, and the crank pin is perpendicular to a main body of the crank 105 and a main body of the connecting rod 106.

When the pumping unit 1 works, the reduction gearbox 104 drives the crank 105 to rotate around the first end, and the crank 105 drives the connecting rod 106 to rotate around the second end. During operation of the pumping unit 1, the connecting rod 106 always rotates around the second end, after multiple rotations, the connecting rod 106 may loose, after the connecting rod 106 loosens, the connecting rod 106 may have uneven stress, possibly break, in general, the pumping unit 1 is provided with a corresponding crank 105 and the connecting rod 106, the connecting rod 106 on one side breaks, and in normal condition of the connecting rod 106 on the other side, the pumping unit 1 may appear rollover, and the pumping unit 1 is scrapped.

In addition, the pumping unit 1 is usually disposed outdoors, so that the pumping unit 1 is affected by the external environment, and the body is eroded, wherein the connecting rod 106 needs to drive the beam of the pumping unit 1 to move, if the connecting rod 106 is affected by the environment and is partially eroded, the connecting rod 106 is unevenly stressed and is broken.

Therefore, the system of the embodiment of the present application further includes a second monitoring device 5, where the second monitoring device 5 is used for monitoring the connecting rod 106, the second monitoring device 5 is fixed on the crank 105, the second monitoring device 5 includes a third distance sensor 501, a second monitoring module 502, and a second communication module 503, the second monitoring module 502 is electrically connected to the third distance sensor 501 and the second communication module 503, and the second communication module 503 is connected to the control cabinet 2 in a wireless communication manner.

The second communication module 503 is connected to the control cabinet 2 in a wireless manner, which is similar to the first communication module 303 being connected to the control cabinet 2 in a wireless manner, and will not be described in detail herein.

The third distance sensor 501 is configured to obtain a third distance from the link 106, and send the third distance to the second monitoring module 502; the second monitoring module 502 is configured to receive the third distance, and send the braking signal to the second communication module 503 if the third distance exceeds a fourth threshold, where the fourth threshold is a distance between the third distance sensor 501 and the connecting rod 106 when the crank 105 and the connecting rod 106 are normally connected.

Optionally, a third distance sensor 501 is located on the body surface of the crank 105, and is directed towards the connecting rod 106. Wherein, the third distance sensor 501 points to the connecting rod 106: the third distance sensor 501 is directed towards the connecting rod 106 at the connection with the crank pin.

The third distance sensor 501 is capable of acquiring a third distance from the connecting rod 106, and since the third distance sensor 501 is located on the crank 105, the distance between the crank 105 and the connecting rod 106 changes after the connecting rod 106 is loosened, and thus the third distance acquired by the third distance sensor 501 located on the crank 105 also changes. If the link 106 falls off, the third distance sensor 501 may acquire a distance from another obstacle that is not located between the crank 105 and the link 106, and thus the distance acquired by the third distance sensor 501 may also become large.

Therefore, if the acquired third distance exceeds the fourth threshold, it is indicated that the link 106 is loose or falling off.

It should be noted that, in the embodiment of the present application, the monitoring process is only illustrated by taking the example that the second monitoring device 5 is fixed on the crank 105 as an example, and in another embodiment, the second monitoring device 5 is fixed on the connecting rod 106, the third distance sensor 501 faces the connecting rod 106 on the other side, the third distance sensor 501 obtains the fifth distance from the other connecting rod 106, and the fifth distance is sent to the second monitoring module 502; the second monitoring module 502 is configured to receive the fifth distance, and send a braking signal to the second communication module 503 if the fifth distance exceeds a sixth threshold, where the sixth threshold is a distance between the third distance sensor and the other connecting rod 106 when the cranks 105 and the connecting rods 106 on both sides are both normally connected.

In another possible implementation, as shown in fig. 1, the pumping unit 1 further includes a horsehead 107 and a wire rope, one end of the wire rope is fixedly connected to the rope hanger 101, the other end of the wire rope is fixedly connected to the horsehead 107, and the rope hanger 101 is located below the horsehead 107.

Since the connection portion of the wire rope and the rope hanger may be worn during the operation of the pumping unit 1, cracks may be generated, resulting in breakage of the wire rope, and in addition, the wire rope may be deformed by force, and after the deformation reaches a certain degree, the wire rope is broken. After the wire rope breaks, the rope hanger 101 can fall off, so that the square clamp 102 and the sucker rod 103 fall off together, and great damage is brought to the pumping unit 1. Therefore, the embodiment of the application also provides a pumping unit control system for determining whether the steel wire rope has a problem.

The system further comprises a third monitoring device 6, which third monitoring device 6 is fixed at the wellhead of the well, which wellhead is located below the line hanger 101. The third monitoring device 6 comprises a fourth distance sensor 601, a third monitoring module 602 and a third communication module 603, wherein the fourth distance sensor 601 is located on the upper surface of the wellhead and faces the rope hanger 101, the third monitoring module 602 is electrically connected with the fourth distance sensor 601 and the third communication module 603 respectively, and the third communication module 603 is in wireless communication connection with the control cabinet 2.

The wireless communication connection between the third communication module 603 and the control cabinet 2 is similar to the wireless communication connection between the first communication module 303 and the control cabinet 2, and will not be described here again.

If the wire rope deforms under the action of force, the wire rope becomes longer and thinner, so that the distance between the rope hanger 101 and the horsehead 107 is larger and larger, the distance between the rope hanger 101 and the wellhead is smaller, and in order to avoid the problems of breakage of the wire rope and falling of the rope hanger 101 caused by deformation of the wire rope, the fourth distance sensor 601 is used for acquiring a fourth distance between the wire rope and the rope hanger 101 and sending the fourth distance to the third monitoring module 602; the third monitoring module 602 is configured to receive the fourth distance, and if the fourth distance is smaller than a fifth threshold, send the braking signal to the third communication module 603, where the fifth threshold is a minimum distance between the fourth distance sensor and the rope hanger 101 during the up-and-down movement of the rope hanger 101 when the wire rope is not deformed.

Thus, after the wire rope becomes longer, the fourth distance is monitored to be smaller than the fifth threshold, so that the technician can replace the wire rope, and serious consequences caused by falling of the wire rope hanger 101 are avoided.

In addition, in order to detect the crack occurring in the steel wire rope, the embodiment of the application also provides a pumping unit control system, the system further comprises a fourth monitoring device 7, the fourth monitoring device 7 is fixed on the rope hanger 101, the fourth monitoring device 7 comprises an ultrasonic sensor 701, a fourth monitoring module 702 and a fourth communication module 703, the ultrasonic sensor 701 is positioned at the joint of the rope hanger 101 and the steel wire rope, the fourth monitoring module 702 is respectively electrically connected with the ultrasonic sensor 701 and the fourth communication module 703, and the fourth communication module 703 is in wireless communication connection with the control cabinet 2.

The ultrasonic sensor 701 is configured to emit an ultrasonic signal forward and receive an ultrasonic reflection signal reflected by an obstacle, the ultrasonic reflection signal being indicative of a crack in a forward object.

The ultrasonic sensor 701 is configured to detect an ultrasonic reflected signal, and send the ultrasonic reflected signal to the fourth monitoring module 702; the fourth monitoring module 702 is configured to receive the ultrasonic reflection signal, and if the ultrasonic reflection signal indicates that the object at the connection has a crack, send the braking signal to the fourth communication module 703; the fourth communication module 703 is configured to receive the braking signal and forward the braking signal to the control cabinet 2.

Alternatively, if the ultrasonic reflected signal detected by the ultrasonic sensor 701 is different from the ultrasonic reflected signal detected previously or has a relatively clear difference, it is indicated that a new crack has occurred in the front object.

It should be noted that, the control cabinet 2 provided in the embodiment of the present application is a device for controlling the operation of the pumping unit 1, and optionally, the control cabinet 2 controls the operation or stop of the pumping unit 1; optionally, the control cabinet 2 has a circuit protection function, and automatically controls the pumping unit 1 to stop running under the conditions of overload, open circuit or short circuit of the pumping unit 1.

Another point to be noted is that the alarm 4 provided by the embodiment of the present application alarms according to any of the monitoring devices provided by the embodiment of the present application, and sends out different alarm information according to the fault information.

Fig. 3 is a schematic diagram of a pumping unit control method according to an embodiment of the present application, which is applied to a pumping unit control system, where the system includes a pumping unit, a control cabinet and a first monitoring device; the control cabinet is electrically connected with the oil pumping unit; the pumping unit comprises a rope hanger, a square clamp and a pumping rod, wherein the pumping rod penetrates through the center of the rope hanger, the square clamp is positioned above the rope hanger, and the square clamp is fixedly connected with the pumping rod; when the pumping unit works, the rope hanger drives the square clamp to move up and down, and the square clamp drives the pumping rod to move up and down; the first monitoring device is fixed on the square clamp and comprises a first distance sensor, a first monitoring module and a first communication module, wherein the first monitoring module is electrically connected with the first distance sensor and the first communication module respectively, and the first communication module is connected with the control cabinet in a wireless communication mode. The method comprises the following steps:

301. The first distance sensor obtains a first distance from the rope hanger and sends the first distance to the first monitoring module.

302. The first monitoring module receives the first distance, and if the first distance exceeds a first threshold value, a braking signal is sent to the first communication module.

The first threshold value is the distance between the first distance sensor and the rope hanger when the pumping unit normally operates.

303. The first communication module receives the braking signal and forwards the braking signal to the control cabinet.

304. And the control cabinet receives the braking signal and controls the pumping unit to stop running according to the braking signal.

According to the control method of the pumping unit, when various faults occur in the pumping unit, the square clamp and the rope hanger are not synchronous, if the square clamp and the rope hanger are not synchronous, the pumping unit is greatly damaged if the pumping unit continues to work, so that the monitoring device is arranged on the square clamp to monitor the distance between the square clamp and the rope hanger, and when the square clamp and the rope hanger are not synchronous, the pumping unit is immediately braked by the control cabinet, and the damage to the pumping unit is reduced due to timely braking, and the rejection rate of the pumping unit and the cost of petroleum exploitation are reduced.

In one possible implementation, the system further comprises an alarm, and the control cabinet is electrically connected with the alarm or establishes a wireless communication connection; the method further comprises the steps of:

the first monitoring module determines fault information of the oil pumping unit according to the first distance and sends the fault information to the first communication module;

the alarm receives the alarm information and sends out the alarm information.

In one possible implementation, if the first distance exceeds the first threshold and does not exceed the second threshold, the first monitoring module obtains first fault information, sends the first fault information to the first communication module, and the first fault information indicates that a sucker rod of the pumping unit is broken;

if the first distance exceeds the second threshold value and does not exceed the third threshold value, the first monitoring module acquires second fault information and sends the second fault information to the first communication module, and the second fault information indicates that the sucker rod is blocked by the oil well;

if the first distance exceeds a third threshold value, the first monitoring module acquires third fault information, and sends the third fault information to the first communication module, wherein the third fault information indicates that the rope hanger falls off;

Wherein the first threshold, the second threshold and the third threshold are sequentially incremented.

the first monitoring module receives the second distance, and if the second distance is different from the reference distance, a braking signal is sent to the first communication module, wherein the reference distance is the distance between the second distance sensor and the sucker rod when the square clamp is fixedly connected with the sucker rod.

In one possible implementation, the first monitoring device further includes a motion sensor, the motion sensor being located at any position of the square clip, the motion sensor being electrically connected to the first monitoring module;

the first monitoring module receives the state, and if the state indicator clip is in a static state, a braking signal is sent to the first communication module.

In one possible implementation manner, the pumping unit further comprises a reduction gearbox, a crank and a connecting rod, wherein a first end of the crank is hinged with the reduction gearbox, a second end of the crank comprises a crank pin, the connecting rod is sleeved on the crank pin, and the crank pin is perpendicular to a main body of the crank and a main body of the connecting rod;

the system also comprises a second monitoring device, wherein the second monitoring device is fixed on the crank and comprises a third distance sensor, a second monitoring module and a second communication module, the second monitoring module is respectively and electrically connected with the third distance sensor and the second communication module, and the second communication module is in wireless communication connection with the control cabinet;

a third distance sensor acquires a third distance between the second monitoring module and the connecting rod, and sends the third distance to the second monitoring module;

The second monitoring module receives the third distance, and if the third distance exceeds a fourth threshold value, a braking signal is sent to the second communication module, wherein the fourth threshold value is the distance between the third distance sensor and the connecting rod when the crank is normally connected with the connecting rod.

In one possible implementation mode, the oil pumping unit further comprises a horsehead and a steel wire rope, one end of the steel wire rope is fixedly connected with the rope hanger, the other end of the steel wire rope is fixedly connected with the horsehead, and the rope hanger is positioned below the horsehead;

the system also comprises a third monitoring device which is fixed at the wellhead of the oil well, and the wellhead is positioned below the rope hanger;

the third monitoring device comprises a fourth distance sensor, a third monitoring module and a third communication module, wherein the fourth distance sensor is positioned on the upper surface of the wellhead and faces the rope hanger, the third monitoring module is respectively and electrically connected with the fourth distance sensor and the third communication module, and the third communication module is in wireless communication connection with the control cabinet;

a fourth distance sensor acquires a fourth distance between the rope hanger and the third monitoring module, and sends the fourth distance to the third monitoring module;

and the third monitoring module receives the fourth distance, and if the fourth distance is smaller than a fifth threshold value, a braking signal is sent to the third communication module, wherein the fifth threshold value is the minimum distance between the fourth distance sensor and the rope hanger in the up-and-down movement process of the rope hanger when the steel wire rope is not deformed.

In one possible implementation mode, the oil pumping unit further comprises a horsehead and a steel wire rope, one end of the steel wire rope is fixedly connected with the rope hanger, the other end of the steel wire rope is fixedly connected with the horsehead, and the rope hanger is suspended below the horsehead;

the system also comprises a fourth monitoring device, wherein the fourth monitoring device is fixed on the rope hanger and comprises an ultrasonic sensor, a fourth monitoring module and a fourth communication module, the ultrasonic sensor is positioned at the joint of the rope hanger and the steel wire rope, the fourth monitoring module is respectively and electrically connected with the ultrasonic sensor and the fourth communication module, and the fourth communication module is in wireless communication connection with the control cabinet;

the ultrasonic sensor detects an ultrasonic reflection signal and sends the ultrasonic reflection signal to the fourth monitoring module;

the fourth monitoring module receives the ultrasonic reflection signal, and if the ultrasonic reflection signal indicates that a crack exists in an object at the joint, a braking signal is sent to the fourth monitoring module;

the fourth communication module receives the braking signal and forwards the braking signal to the control cabinet.

It will be understood by those skilled in the art that all or part of the steps for implementing the above embodiments may be implemented by hardware, or may be implemented by a program for instructing relevant hardware, where the program may be stored in a computer readable storage medium, and the above storage medium may be a read-only memory, a magnetic disk or an optical disk, etc.

The foregoing is merely an alternative embodiment of the present application and is not intended to limit the embodiment of the present application, and any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the embodiment of the present application should be included in the protection scope of the present application.

Claims

1. A pumping unit control system, characterized in that the system comprises a pumping unit (1), a control cabinet (2) and a first monitoring device (3); the control cabinet (2) is electrically connected with the oil pumping unit (1); the system also comprises an alarm (4), wherein the control cabinet (2) is electrically connected with the alarm (4) or is in wireless communication connection;

the pumping unit (1) comprises a rope hanger (101), a square clamp (102) and a pumping rod (103), wherein the square clamp (102) is positioned above the rope hanger (101), the square clamp (102) is fixedly connected with the pumping rod (103), and the pumping rod (103) penetrates through the center of the rope hanger (101);

when the oil pumping unit (1) works, the rope hanger (101) drives the square clamp (102) to move up and down, and the square clamp (102) drives the oil pumping rod (103) to move up and down;

The first monitoring device (3) is fixed on the square clamp (102), the first monitoring device (3) comprises a first distance sensor (301), a first monitoring module (302) and a first communication module (303), the first distance sensor (301) is located on the lower surface of the square clamp (102), the first monitoring module (302) is electrically connected with the first distance sensor (301) and the first communication module (303) respectively, and the first communication module (303) is in wireless communication connection with the control cabinet (2);

the first distance sensor (301) is configured to acquire a first distance from the rope hanger (101), and send the first distance to the first monitoring module (302);

the first monitoring module (302) is configured to receive the first distance, and if the first distance exceeds a first threshold, send a braking signal to the first communication module (303), where the first threshold is a distance between the first distance sensor (301) and the rope hanger (101) when the pumping unit (1) is operating normally;

the first communication module (303) is used for receiving the braking signal and forwarding the braking signal to the control cabinet (2);

The control cabinet (2) is used for receiving the braking signal and controlling the pumping unit (1) to stop running according to the braking signal;

the first monitoring module (302) is further configured to determine fault information of the pumping unit (1) according to the first distance, and send the fault information to the first communication module (303);

the first communication module (303) is further configured to receive the fault information and forward the fault information to the control cabinet (2);

the control cabinet (2) is also used for receiving the fault information, determining alarm information matched with the fault information and sending the alarm information to the alarm (4);

the alarm (4) is used for receiving the alarm information and sending out the alarm information;

the first monitoring module (302) is configured to obtain first fault information if the first distance exceeds the first threshold and does not exceed a second threshold, and send the first fault information to the first communication module (303), where the first fault information indicates that a sucker rod (103) of the pumping unit (1) is broken;

the first monitoring module (302) is configured to acquire second fault information if the first distance exceeds the second threshold and does not exceed a third threshold, and send the second fault information to the first communication module (303), where the second fault information indicates that the sucker rod (103) is blocked by an oil well;

The first monitoring module (302) is configured to acquire third fault information if the first distance exceeds the third threshold, send the third fault information to the first communication module (303), and the third fault information indicates that the rope hanger (101) is dropped;

2. The system according to claim 1, wherein the first monitoring device (3) further comprises a second distance sensor (304), the second distance sensor (304) being electrically connected with the first monitoring module (302);

the second distance sensor (304) is positioned on the upper surface of the square clamp (102), and the second distance sensor (304) faces the sucker rod (103); alternatively, the second distance sensor (304) comprises a sensor body and a target component, wherein the sensor body is used for detecting the position of the target component, the sensor body is positioned on the upper surface of the square clamp (102), and the target component is positioned on the sucker rod (103) and is opposite to the sensor body;

the second distance sensor (304) is used for acquiring a second distance between the second distance sensor and the sucker rod (103), and sending the second distance to the first monitoring module (302);

The first monitoring module (302) is further configured to receive the second distance, and if the second distance is different from a reference distance, send the braking signal to the first communication module (303), where the reference distance is a distance between the second distance sensor (304) and the sucker rod (103) when the square clip (102) is fixedly connected to the sucker rod (103).

3. The system according to claim 1, wherein the first monitoring device (3) further comprises a motion sensor (305), the motion sensor (305) being located at any position of the square clip (102), the motion sensor (305) being electrically connected to the first monitoring module (302);

the motion sensor (305) is configured to detect a state of the square clamp (102), and send the state to the first monitoring module (302), where the state indicates that the square clamp (102) is in a moving state or in a stationary state;

the first monitoring module (302) is configured to receive the state, and if the state indicates that the square clip (102) is in a static state, send the braking signal to the first communication module (303).

4. A system according to any one of claims 1 to 3, wherein the pumping unit (1) further comprises a reduction gearbox (104), a crank (105) and a connecting rod (106), a first end of the crank (105) being hinged to the reduction gearbox (104), a second end of the crank (105) comprising a crank pin, the connecting rod (106) being sleeved on the crank pin, and the crank pin being perpendicular to the body of the crank (105) and to the body of the connecting rod (106);

when the oil pumping unit (1) works, the reduction gearbox (104) drives the crank (105) to rotate around the first end, and the crank (105) drives the connecting rod (106) to rotate around the second end;

the system further comprises a second monitoring device (5), wherein the second monitoring device (5) is fixed on the crank (105), the second monitoring device (5) comprises a third distance sensor (501), a second monitoring module (502) and a second communication module (503), the second monitoring module (502) is respectively and electrically connected with the third distance sensor (501) and the second communication module (503), and the second communication module (503) is in wireless communication connection with the control cabinet (2);

The third distance sensor (501) is configured to acquire a third distance from the link (106), and send the third distance to the second monitoring module (502);

the second monitoring module (502) is configured to receive the third distance, and if the third distance exceeds a fourth threshold, send the braking signal to the second communication module (503), where the fourth threshold is a distance between the third distance sensor (501) and the connecting rod (106) when the crank (105) and the connecting rod (106) are normally connected.

5. A system according to any one of claims 1 to 3, wherein the pumping unit (1) further comprises a horsehead (107) and a wire rope, one end of the wire rope being fixedly connected to the rope hanger (101), the other end of the wire rope being fixedly connected to the horsehead (107), the rope hanger (101) being located below the horsehead (107);

the system further comprises a third monitoring device (6), wherein the third monitoring device (6) is fixed at the wellhead of the oil well, and the wellhead is positioned below the rope hanger (101);

the third monitoring device (6) comprises a fourth distance sensor (601), a third monitoring module (602) and a third communication module (603), wherein the fourth distance sensor (601) is positioned on the upper surface of the wellhead and faces the hanger (101), the third monitoring module (602) is electrically connected with the fourth distance sensor (601) and the third communication module (603) respectively, and the third communication module (603) is in wireless communication connection with the control cabinet (2);

The fourth distance sensor (601) is configured to acquire a fourth distance between the fourth distance sensor and the rope hanger (101), and send the fourth distance to the third monitoring module (602);

the third monitoring module (602) is configured to receive the fourth distance, and if the fourth distance is smaller than a fifth threshold, send the braking signal to the third communication module (603), where the fifth threshold is a minimum distance between the fourth distance sensor and the rope hanger (101) in an up-and-down movement process of the rope hanger (101) when the steel wire rope is not deformed.

6. A system according to any one of claims 1 to 3, wherein the pumping unit (1) further comprises a horsehead (107) and a wire rope, one end of the wire rope being fixedly connected to the rope hanger (101), the other end of the wire rope being fixedly connected to the horsehead (107), the rope hanger (101) being suspended below the horsehead (107);

the system further comprises a fourth monitoring device (7), the fourth monitoring device (7) is fixed on the rope hanger (101), the fourth monitoring device (7) comprises an ultrasonic sensor (701), a fourth monitoring module (702) and a fourth communication module (703), the ultrasonic sensor (701) is positioned at the joint of the rope hanger (101) and the steel wire rope, the fourth monitoring module (702) is electrically connected with the ultrasonic sensor (701) and the fourth communication module (703) respectively, and the fourth communication module (703) is in wireless communication connection with the control cabinet (2);

The ultrasonic sensor (701) is used for detecting an ultrasonic reflection signal and sending the ultrasonic reflection signal to the fourth monitoring module (702);

the fourth monitoring module (702) is configured to receive the ultrasonic reflection signal, and if the ultrasonic reflection signal indicates that a crack exists in the object at the connection position, send the braking signal to the fourth monitoring module (703);

the fourth communication module (703) is configured to receive the braking signal and forward the braking signal to the control cabinet (2).

7. A pumping unit control method, characterized by being performed by a pumping unit control system as defined in any one of claims 1 to 6, the method comprising:

the first distance sensor (301) acquires a first distance from the rope hanger (101) and sends the first distance to the first monitoring module (302);

the first monitoring module (302) receives the first distance, and if the first distance exceeds a first threshold value, a braking signal is sent to the first communication module (303), wherein the first threshold value is the distance between the first distance sensor (301) and the rope hanger (101) when the oil pumping unit (1) operates normally;

The first communication module (303) receives the braking signal and forwards the braking signal to the control cabinet (2);

the control cabinet (2) receives the braking signal and controls the pumping unit (1) to stop running according to the braking signal;

the method further comprises the steps of:

the first monitoring module (302) determines fault information of the pumping unit (1) according to the first distance, and sends the fault information to the first communication module (303);

the first communication module (303) receives the fault information and forwards the fault information to the control cabinet (2);

the control cabinet (2) receives the fault information, determines alarm information matched with the fault information and sends the alarm information to the alarm (4);

the alarm (4) receives the alarm information and sends out the alarm information;

wherein the first monitoring module (302) determines fault information of the pumping unit (1) according to the first distance, and sends the fault information to the first communication module (303), and the method comprises the following steps:

if the first distance exceeds the first threshold value and does not exceed the second threshold value, the first monitoring module (302) acquires first fault information, and sends the first fault information to the first communication module (303), wherein the first fault information indicates that a sucker rod (103) of the oil pumping unit (1) is broken;

If the first distance exceeds the second threshold value and does not exceed a third threshold value, the first monitoring module (302) acquires second fault information, and sends the second fault information to the first communication module (303), wherein the second fault information indicates that the sucker rod (103) is blocked by an oil well;

if the first distance exceeds the third threshold value, the first monitoring module (302) acquires third fault information, and sends the third fault information to the first communication module (303), wherein the third fault information indicates that the rope hanger (101) falls off;