Plunger gas lift control method and system

Abstract

The invention discloses a plunger gas lift control method and system. The plunger gas lift control method comprises the steps that historical production data of a gas well are obtained; setting a load coefficient threshold value, a maximum well shut-in time length, a follow current production time length and a follow current adjustment time step length according to the historical production data of the gas well; state parameters in gas well production are collected in real time; calculating a load coefficient according to the state parameters in the gas well production; when the load coefficient reaches a load coefficient threshold value or the well shut-in duration reaches the maximum well shut-in duration, well opening is executed; determining a minimum oil pressure value and a maximum oil pressure value during liquid discharge oscillation; the oil pressure is the pressure at a gas well wellhead oil pipe; determining the liquid discharge amount according to the minimum oil pressure value and the maximum oil pressure value; and when the liquid drainage amount is not within the preset range, the follow current production duration is adjusted according to the liquid drainage amount and the follow current adjustment time step length, periodic circulation switch control and automatic optimization are conducted on the plunger gas lift well according to the set load coefficient threshold value and the liquid drainage amount, and efficient liquid drainage and stable operation of the plunger gas lift well are achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of plunger gas lift, and in particular to a plunger gas lift control method and system. Background Art

[0002] This section is intended to provide a background or context to the embodiments of the invention recited in the claims. No description herein is admitted to be prior art by inclusion in this section.

[0003] The plunger gas lift technology controls the plunger liquid lifting operation by setting appropriate operating parameters. The commonly used control method is the timed and constant pressure well switching method. It requires manual calculation and setting of operating parameters based on the energy recovery of the gas well and the liquid volume. The setting process is labor-intensive and if the analysis is not timely or accurate, it will affect the technical effect.

[0004] As the number of wells using plunger gas lift increases, the existing control methods cannot meet the control needs due to the large workload of manual parameter adjustment and insufficient control refinement, resulting in liquid accumulation and water flooding in gas wells, affecting the gas well production capacity and reducing the gas well recovery rate. Therefore, plunger gas lift control is urgently needed to solve the above problems. Summary of the invention

[0005] An embodiment of the present invention provides a plunger gas lift control method for improving plunger liquid lift efficiency and normal operation rate, the method comprising:

[0006] Obtain historical production data of gas wells;

[0007] According to the historical production data of the gas well, the load factor threshold, the maximum shut-in time, the continuous flow production time and the continuous flow adjustment time step are set;

[0008] Real-time collection of state parameters during gas well production;

[0009] Calculate the load factor based on the state parameters in gas well production;

[0010] When the load factor reaches the load factor threshold or the well shut-in time reaches the maximum well shut-in time, the well is opened;

[0011] Determine the minimum and maximum oil pressures during the discharge shock; the oil pressure is the pressure at the wellhead oil pipe of the gas well;

[0012] Determine the discharge volume based on the minimum and maximum oil pressures;

[0013] When the discharge volume is not within the preset range, the continuous flow production time is adjusted according to the discharge volume and the continuous flow adjustment time step.

[0014] The embodiment of the present invention further provides a plunger gas lift control system for improving the plunger liquid lift efficiency and the normal operation rate, the system comprising:

[0015] A setting unit, used to obtain historical production data of the gas well, and set a load factor threshold, a maximum shut-in time, a continuous flow production time, and a continuous flow adjustment time step according to the historical production data of the gas well;

[0016] A collection unit, used for collecting state parameters of gas well production in real time;

[0017] An automatic execution unit, used for calculating the load factor according to the state parameters in the gas well production, and executing the well opening when the load factor reaches the load factor threshold or the well shut-in time reaches the maximum well shut-in time;

[0018] The control unit is used to determine the minimum and maximum oil pressures during the discharge oscillation. The oil pressure is the pressure at the wellhead oil pipe of the gas well. The discharge volume is determined according to the minimum and maximum oil pressures. When the discharge volume is not within a preset range, the continuous flow production time is adjusted according to the discharge volume and the continuous flow adjustment time step.

[0019] In an embodiment of the present invention, historical production data of the gas well is obtained; a load factor threshold, a maximum shut-in time, a continuous flow production time and a continuous flow adjustment time step are set according to the historical production data of the gas well; state parameters in the gas well production are collected in real time; the load factor is calculated according to the state parameters in the gas well production; when the load factor reaches the load factor threshold or the shut-in time reaches the maximum shut-in time, the well is opened; the minimum oil pressure and the maximum oil pressure during the fluid discharge oscillation are determined; the oil pressure is the pressure at the wellhead oil pipe of the gas well; the fluid discharge volume is determined according to the minimum oil pressure and the maximum oil pressure; when the fluid discharge volume is not within a preset range, the continuous flow production time is adjusted according to the fluid discharge volume and the continuous flow adjustment time step. Compared with the prior art, the fluid discharge volume is determined according to the minimum oil pressure and the maximum oil pressure; the continuous flow production time is adjusted according to the fluid discharge volume and the continuous flow adjustment time step. Without adding equipment, invalid shut-in and fluid lifting overload operation during plunger gas lift operation are avoided, thereby improving the plunger lifting efficiency and the normal operation rate. The plunger gas lift well is periodically cycled on and off controlled and automatically optimized according to the set load factor threshold and discharge volume, so as to achieve efficient discharge and stable operation of the plunger gas lift well. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the prior art descriptions. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0021] Figure 1 A schematic flow chart of the plunger gas lift control method provided by the present invention;

[0022] Figure 2A schematic flow chart of the plunger gas lift control method provided by the present invention;

[0023] Figure 3 A schematic diagram of a plunger gas lift operation curve of a gas well provided by the present invention;

[0024] Figure 4 A schematic diagram of the plunger gas lift operation curve after optimization of the gas well provided by the present invention;

[0025] Figure 5 A schematic diagram of the plunger gas lift control system provided by the present invention. DETAILED DESCRIPTION

[0026] To make the purpose, technical solution and advantages of the embodiments of the present invention more clear, the embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings. Here, the exemplary embodiments of the present invention and their descriptions are used to explain the present invention, but are not intended to limit the present invention.

[0027] Figure 1 A flow chart corresponding to a plunger gas lift control method provided in an embodiment of the present invention is shown in FIG. Figure 1 As shown, the method includes:

[0028] Step 101, obtaining historical production data of gas wells.

[0029] Step 102, setting the load factor threshold, maximum shut-in time, continuous production time and continuous adjustment time step according to the historical production data of the gas well.

[0030] According to the historical production data of the gas well, the gas well operation parameters are analyzed, and the load factor threshold, maximum shut-in time, continuous flow production time and continuous flow adjustment time step are set.

[0031] In the embodiment of the present invention, the duration of continuous production is determined according to the change of casing pressure during the continuous production period. After the plunger lifts the liquid to the wellhead, the gas well enters the continuous flow stage, and the change of casing pressure of the gas well is monitored in real time. When the casing pressure increases, the time of opening the well is determined as the continuous production duration. The setting basis is that the casing pressure increases during the continuous production process, that is, the increase in the oil-casing pressure difference reflects that liquid accumulation begins to appear in the gas well.

[0032] Step 103: collect state parameters of the gas well during production in real time.

[0033] Step 104, calculating the load factor according to the state parameters in the gas well production.

[0034] The state parameters in gas well production include casing pressure, oil pressure and back pressure.

[0035] Calculate the load factor based on casing pressure, oil pressure and back pressure.

[0036] It should be noted that the casing pressure refers to the pressure in the wellhead casing annulus; the back pressure refers to the pipeline transmission pressure.

[0037] The load factor is calculated by the ratio of the difference between the shut-in casing pressure and the shut-in oil pressure to the difference between the shut-in casing pressure and the pressure after wellhead throttling, i.e., the back pressure.

[0038] The difference between the shut-in casing pressure and the shut-in oil pressure reflects the liquid accumulation in the gas wellbore and is the resistance to the plunger gas lift operation. The difference between the shut-in casing pressure and the pressure after wellhead throttling reflects the pure power provided for plunger lift. The ratio of the two is the comparison between resistance and power. The smaller the value, the more favorable it is to the plunger liquid lift operation.

[0039] Step 105 , when the load factor reaches a load factor threshold or the well shut-in duration reaches a maximum well shut-in duration, opening the well is performed.

[0040] When the plunger gas lift well is in the shut-in state, the load coefficient is monitored and analyzed in real time. When the set load coefficient threshold is reached, the well is opened; if the load coefficient threshold cannot be reached, the well is opened when the shut-in time reaches the maximum shut-in time.

[0041] Step 106, determining the minimum and maximum oil pressures during the discharge oscillation.

[0042] Oil pressure is the pressure at the oil pipe at the wellhead of the gas well.

[0043] Step 107, determining the amount of fluid discharged according to the minimum oil pressure and the maximum oil pressure.

[0044] After the well is opened, the information of the plunger lifting liquid to the wellhead is monitored, and the changes in the oil pressure of the gas well are tracked and analyzed in real time. When the oil pressure reaches the minimum value and then increases, the discharge shock occurs, and the discharge volume is automatically calculated based on the pressure difference between the minimum oil pressure and the maximum oil pressure.

[0045] The specific calculation formula is as follows:

[0046]

[0047] ΔPt=Pt(max)-Pt(min)

[0048] Ql represents the amount of liquid discharged during the plunger gas lift cycle, K represents the correction coefficient, ΔPt represents the pressure difference between the maximum oil pressure and the minimum oil pressure during plunger gas lift discharge, ρ represents the density of the produced liquid, g represents the acceleration of gravity, Pt(max) represents the maximum oil pressure, and Pt(min) represents the minimum oil pressure.

[0049] Step 108, when the discharge volume is not within the preset range, adjusting the continuous flow production time according to the discharge volume and the continuous flow adjustment time step.

[0050] In the embodiment of the present invention, the minimum and maximum values ​​of the liquid discharge volume are set according to the historical production data of the gas well.

[0051] When the discharge volume is less than the minimum discharge volume, the plunger gas lift operates inefficiently and enters the continuous flow optimization process. The continuous flow production time is increased according to the continuous flow adjustment time step to improve the gas well opening rate. After the optimization is completed, the well shut-in pressure recovery stage is entered, and then the next cycle operation is carried out.

[0052] When the discharge volume is greater than the maximum discharge volume, the plunger lifts too much liquid and is overloaded, and the flow optimization process is also entered. The flow optimization time step is adjusted according to the flow to shorten the flow production time and improve the operation stability of the plunger gas lift. After the optimization is completed, the well shut-in pressure recovery stage is entered before the next cycle is carried out.

[0053] The above scheme determines the discharge volume according to the minimum and maximum oil pressures; adjusts the continuous flow production time according to the discharge volume and the continuous flow adjustment time step, and avoids invalid well shut-in and liquid lifting overload operation during plunger gas lift operation without adding equipment, thereby improving the plunger lift efficiency and normal operation rate. The plunger gas lift well is periodically cycled and switched on and off and automatically optimized according to the set load factor threshold and discharge volume, achieving efficient liquid discharge and stable operation of the plunger gas lift well.

[0054] In the embodiment of the present invention, after the discharge volume is determined according to the minimum oil pressure and the maximum oil pressure, when the discharge volume is within a preset range, the continuous flow production time is kept unchanged.

[0055] When the discharge volume is within the preset range, the continuous flow production time is maintained unchanged. After completion, the well shut-in pressure recovery stage is entered, and then the next cycle operation is carried out.

[0056] In step 108 of the embodiment of the present invention, the continuous flow production time is adjusted according to the discharge volume and the continuous flow adjustment time step, and the step flow is as follows: Figure 2 As shown, the details are as follows:

[0057] Step 201, setting a minimum and a maximum discharge volume according to historical production data of the gas well.

[0058] Step 202: when the discharge volume is less than the minimum discharge volume, the continuous flow production time is increased according to the continuous flow adjustment time step.

[0059] When the discharge volume is less than the minimum discharge volume, the plunger gas lift operates inefficiently and enters the continuous flow optimization process. The continuous flow production time is increased according to the continuous flow adjustment time step to improve the gas well opening rate. After the optimization is completed, the well shut-in pressure recovery stage is entered, and then the next cycle operation is carried out.

[0060] Step 203, when the discharge volume is greater than the maximum discharge volume, shorten the continuous flow production time according to the continuous flow adjustment time step.

[0061] When the discharge volume is greater than the maximum discharge volume, the plunger lifts too much liquid and is overloaded, and the flow optimization process is also entered. The flow optimization time step is adjusted according to the flow to shorten the flow production time and improve the operation stability of the plunger gas lift. After the optimization is completed, the well shut-in pressure recovery stage is entered before the next cycle is carried out.

[0062] The above scheme adjusts the continuous flow production time according to the discharge volume and the continuous flow adjustment time step, realizes automatic optimization control of the plunger operation without adding equipment, avoids invalid well shut-in and liquid lifting overload operation during plunger gas lift operation, and improves the plunger lifting efficiency and normal operation rate.

[0063] Figure 3 This is a plunger gas lift operation curve of a gas well provided in an embodiment of the present invention. The plunger gas lift control method provided by the present invention is described below using the gas well as an example.

[0064] Figure 3 In the figure, t1 is the well closing process, t2 is the well opening process, P1 is the minimum oil pressure during fluid discharge, P2 is the maximum oil pressure after fluid discharge, P1 is the minimum casing pressure after well opening, ΔP is the increase in casing pressure after the gas well begins to accumulate fluid after the casing pressure reaches the minimum value, and t is the set continuous production time.

[0065] In the embodiment of the present invention, 10 to 15 normal operating production cycles that can represent the production characteristics are selected through the historical curve of the gas well, and the plunger lift volume of 0.15 cubic meters is calculated based on P2 and P1. The minimum and maximum discharge volumes of the plunger gas lift of the gas well are set, and the minimum discharge volume is set to 0.08 cubic meters, and the maximum discharge volume is set to 0.3 cubic meters.

[0066] The initial continuous flow production time t of the gas well is set according to P1 and ΔP on the curve. The continuous flow production time of this well is set to 5 hours. At the same time, the continuous flow adjustment time step is set according to the change of ΔP. The continuous flow increase time is set to 30 minutes, and the continuous flow reduction time is set to 10 minutes.

[0067] The gas well opening load factor threshold is set according to the oil pressure, casing pressure and back pressure before the gas well is opened, and it is set to 0.4 for this well.

[0068] After the setting is completed, the optimization parameters are started. During the shut-in time t1, the changes in the load coefficient of the gas well are monitored in real time. When the load coefficient reaches 0.4, the well is opened and enters the t2 production stage.

[0069] During the t2 production stage, the changes in the gas well tubing pressure are monitored in real time. When the minimum oil pressure appears, the value is recorded. When the minimum oil pressure appears, the value is recorded at the same time. The plunger discharge volume of this cycle is calculated based on the minimum oil pressure and the maximum oil pressure. The discharge volume of this cycle is 0.16 cubic meters.

[0070] Compare the discharge volume of this cycle with the set minimum and maximum discharge volumes. When the discharge volume is within the preset range, the continuous flow production duration is maintained unchanged. When the discharge volume is less than the minimum discharge volume, the continuous flow production duration is increased according to the continuous flow adjustment time step; when the discharge volume is greater than the maximum discharge volume, the continuous flow production duration is shortened according to the continuous flow adjustment time step.

[0071] After the continuous flow production time is completed, the well shut-in phase t1 is entered and the next cycle optimization operation begins. Then the operation is repeated periodically to achieve long-term stable operation of the plunger gas lift well.

[0072] After the optimization operation, the optimization operation curve is as follows: Figure 4 As shown, the gas wells can achieve automatic optimization of parameters without adding supporting equipment for plunger gas lift, without the need for manual analysis and management, and maintain long-term effective drainage and stable production of the gas wells. The daily gas production has increased from 4,000 cubic meters to 13,000 cubic meters, an increase of 75%, and the liquid production has increased from 0.15 cubic meters to 0.48 cubic meters, with a significant production increase effect.

[0073] The present invention also provides a plunger gas lift control system, as described in the following embodiments. Figure 5 As shown, the system comprises:

[0074] The setting unit 501 is used to obtain the historical production data of the gas well, and set the load factor threshold, the maximum shut-in time, the continuous flow production time and the continuous flow adjustment time step according to the historical production data of the gas well;

[0075] A collection unit 502 is used to collect state parameters of gas well production in real time;

[0076] The automatic execution unit 503 is used to calculate the load factor according to the state parameters in the gas well production, and to open the well when the load factor reaches the load factor threshold or the well shut-in time reaches the maximum well shut-in time;

[0077] The control unit 504 is used to determine the minimum and maximum oil pressures during the fluid discharge oscillations. The oil pressure is the pressure at the wellhead oil pipe of the gas well. The fluid discharge volume is determined based on the minimum and maximum oil pressures. When the fluid discharge volume is not within a preset range, the continuous flow production time is adjusted based on the fluid discharge volume and the continuous flow adjustment time step.

[0078] When the plunger gas lift well is in the shut-in state, the automatic execution unit monitors and analyzes the numerical changes of the gas well load coefficient in real time. When the load coefficient reaches the set numerical range, the well opening command is executed and sent to the automatic control valve to realize the well opening.

[0079] After the well is opened, the plunger lifts the accumulated liquid in the wellbore upward. When the lifted liquid reaches the wellhead and is discharged, the pressure in the gas well tubing will show an oscillation feature of first decreasing and then increasing. The amplitude of the pressure oscillation can reflect the amount of liquid discharged from the gas well. When the plunger rises without lifting the accumulated liquid, there is no pressure oscillation feature.

[0080] In the embodiment of the present invention, the state parameters in the gas well production include casing pressure, oil pressure, and back pressure. The automatic execution unit 503 is specifically used for:

[0081] The load coefficient is calculated based on the casing pressure, oil pressure and back pressure; the casing pressure is the pressure at the wellhead casing annulus; the back pressure is the pipeline transmission pressure.

[0082] In the embodiment of the present invention, the control unit 504 is further configured to:

[0083] After the discharge volume is determined according to the minimum oil pressure and the maximum oil pressure, when the discharge volume is within a preset range, the continuous flow production time is maintained unchanged.

[0084] In the embodiment of the present invention, the control unit 504 is specifically used for:

[0085] Set the minimum and maximum discharge volume according to the historical production data of the gas well;

[0086] When the discharge volume is less than the minimum discharge volume, the continuous flow production time is increased according to the continuous flow adjustment time step;

[0087] When the discharge volume is greater than the maximum discharge volume, the time step is adjusted according to the continuous flow to shorten the continuous flow production time.

[0088] When the plunger lifts the accumulated liquid to the wellhead, the discharge volume is determined according to the minimum and maximum oil pressures. When the discharge volume is within the set range, the continuous flow production time is kept unchanged. After the continuous flow ends, the well shut-in command is executed to enter the well shut-in stage. If the discharge volume is less than the minimum discharge volume, it indicates that the well has a poor lifting effect and the plunger is inefficient. According to the continuous flow adjustment time step, the continuous flow production time is increased to increase the amount of liquid accumulated in the gas wellbore, so that the plunger gas lift is in efficient liquid discharge operation; if the discharge volume is greater than the maximum discharge volume, it indicates that the plunger lifts too much liquid, and it is easy to cause the plunger to lift the accumulated liquid, resulting in the liquid falling back to the bottom of the well, and eventually causing the accumulated liquid to flood. At this time, according to the continuous flow adjustment time step, the continuous flow production time is shortened to reduce the amount of liquid accumulated in the wellbore. After the continuous flow ends, the well shut-in command is executed to enter the well shut-in stage.

[0089] In the embodiment of the present invention, the control unit 504 is specifically used for:

[0090] The specific calculation formula for determining the discharge volume based on the minimum and maximum oil pressures is as follows:

[0091]

[0092] ΔPt=Pt(max)-Pt(min)

[0093] Ql represents the amount of liquid discharged during the plunger gas lift cycle, K represents the correction coefficient, ΔPt represents the pressure difference between the maximum oil pressure and the minimum oil pressure during plunger gas lift discharge, ρ represents the density of the produced liquid, g represents the acceleration of gravity, Pt(max) represents the maximum oil pressure, and Pt(min) represents the minimum oil pressure.

[0094] Since the principle of solving the problem by this system is similar to that of the plunger gas lift control method, the implementation of this system can refer to the implementation of the plunger gas lift control method, and the repeated parts will not be repeated.

[0095] In an embodiment of the present invention, historical production data of the gas well is obtained; a load factor threshold, a maximum shut-in time, a continuous flow production time and a continuous flow adjustment time step are set according to the historical production data of the gas well; state parameters in the gas well production are collected in real time; the load factor is calculated according to the state parameters in the gas well production; when the load factor reaches the load factor threshold or the shut-in time reaches the maximum shut-in time, the well is opened; the minimum oil pressure and the maximum oil pressure during the fluid discharge oscillation are determined; the oil pressure is the pressure at the wellhead oil pipe of the gas well; the fluid discharge volume is determined according to the minimum oil pressure and the maximum oil pressure; when the fluid discharge volume is not within a preset range, the continuous flow production time is adjusted according to the fluid discharge volume and the continuous flow adjustment time step. Compared with the prior art, the fluid discharge volume is determined according to the minimum oil pressure and the maximum oil pressure; the continuous flow production time is adjusted according to the fluid discharge volume and the continuous flow adjustment time step. Without adding equipment, invalid shut-in and fluid lifting overload operation during plunger gas lift operation are avoided, thereby improving the plunger lifting efficiency and the normal operation rate. The plunger gas lift well is periodically cycled on and off controlled and automatically optimized according to the set load factor threshold and discharge volume, so as to achieve efficient discharge and stable operation of the plunger gas lift well.

[0096] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0097] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0098] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0099] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process in the computer or other programmable device. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0100] The specific embodiments described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A plunger gas lift control method, characterized in that: include: Obtain historical production data of gas wells; According to the historical production data of the gas well, the load factor threshold, the maximum shut-in time, the continuous flow production time and the continuous flow adjustment time step are set; Real-time collection of state parameters during gas well production; Calculate the load factor based on the state parameters in gas well production; When the load factor reaches the load factor threshold or the well shut-in time reaches the maximum well shut-in time, the well is opened; Determine the minimum and maximum oil pressures during the discharge shock; the oil pressure is the pressure at the wellhead oil pipe of the gas well; Determine the discharge volume based on the minimum and maximum oil pressures; When the discharge volume is not within the preset range, the continuous flow production time is adjusted according to the discharge volume and the continuous flow adjustment time step.

2. The plunger gas lift control method according to claim 1, characterized in that: The state parameters in gas well production include casing pressure, oil pressure, and back pressure. The load factor is calculated based on the state parameters in gas well production, including: The load coefficient is calculated based on the casing pressure, oil pressure and back pressure; the casing pressure is the pressure at the wellhead casing annulus; the back pressure is the pipeline transmission pressure.

3. The plunger gas lift control method according to claim 1, characterized in that: After determining the amount of fluid to be discharged based on the minimum and maximum oil pressures, it also includes: When the discharge volume is within the preset range, the continuous flow production time is maintained unchanged.

4. The plunger gas lift control method according to claim 1, characterized in that: The adjusting of the continuous flow production time according to the discharge volume and the continuous flow adjustment time step includes: Set the minimum and maximum discharge volume according to the historical production data of the gas well; When the discharge volume is less than the minimum discharge volume, the continuous flow production time is increased according to the continuous flow adjustment time step; When the discharge volume is greater than the maximum discharge volume, the time step is adjusted according to the continuous flow to shorten the continuous flow production time.

5. The plunger gas lift control method according to claim 1, characterized in that: The specific calculation formula for determining the discharge volume based on the minimum and maximum oil pressures is as follows: ΔPt=Pt(max)-Pt(min) Ql represents the amount of liquid discharged during the plunger gas lift cycle, K represents the correction coefficient, ΔPt represents the pressure difference between the maximum oil pressure and the minimum oil pressure during plunger gas lift discharge, ρ represents the density of the produced liquid, g represents the acceleration of gravity, Pt(max) represents the maximum oil pressure, and Pt(min) represents the minimum oil pressure.

6. A plunger gas lift control system, characterized in that: include: A setting unit, used to obtain historical production data of the gas well, and set a load factor threshold, a maximum shut-in time, a continuous flow production time, and a continuous flow adjustment time step according to the historical production data of the gas well; A collection unit, used for collecting state parameters of gas well production in real time; An automatic execution unit, used for calculating the load factor according to the state parameters in the gas well production, and executing the well opening when the load factor reaches the load factor threshold or the well shut-in time reaches the maximum well shut-in time; The control unit is used to determine the minimum and maximum oil pressures during the discharge oscillation. The oil pressure is the pressure at the wellhead oil pipe of the gas well. The discharge volume is determined according to the minimum and maximum oil pressures. When the discharge volume is not within a preset range, the continuous flow production time is adjusted according to the discharge volume and the continuous flow adjustment time step.

7. The plunger gas lift control system according to claim 6, characterized in that: The state parameters in gas well production include casing pressure, oil pressure, and back pressure. The automatic execution unit is specifically used for: The load coefficient is calculated based on the casing pressure, oil pressure and back pressure; the casing pressure is the pressure at the wellhead casing annulus; the back pressure is the pipeline transmission pressure.

8. The plunger gas lift control system according to claim 6, characterized in that: The control unit is also used for: After the discharge volume is determined according to the minimum oil pressure and the maximum oil pressure, when the discharge volume is within a preset range, the continuous flow production time is maintained unchanged.

9. The plunger gas lift control system according to claim 6, characterized in that: The control unit is specifically used for: Set the minimum and maximum discharge volume according to the historical production data of the gas well; When the discharge volume is less than the minimum discharge volume, the continuous flow production time is increased according to the continuous flow adjustment time step; When the discharge volume is greater than the maximum discharge volume, the time step is adjusted according to the continuous flow to shorten the continuous flow production time.

10. The plunger gas lift control system according to claim 6, characterized in that: The control unit is specifically used for: The specific calculation formula for determining the discharge volume based on the minimum and maximum oil pressures is as follows: ΔPt=Pt(max)-Pt(min) Ql represents the amount of liquid discharged during the plunger gas lift cycle, K represents the correction coefficient, ΔPt represents the pressure difference between the maximum oil pressure and the minimum oil pressure during plunger gas lift discharge, ρ represents the density of the produced liquid, g represents the acceleration of gravity, Pt(max) represents the maximum oil pressure, and Pt(min) represents the minimum oil pressure.

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