Deepwater Christmas tree control system and method

Abstract

The invention discloses a deepwater Christmas tree control system and method, and the method comprises the steps: building a LedaFlow dynamic model, arranging two groups of temperature and pressure PID controllers on a deepwater Christmas tree shaft pipeline, enabling the variable of a first temperature PID controller to be an oil reservoir temperature, fixing the reading of an underground temperature transmitter, adjusting the oil reservoir temperature, and enabling the underground temperature to be consistent with the actual temperature data; the variable of the second temperature PID controller is the shaft heat transfer coefficient, the reading of the second temperature transmitter is fixed, and the shaft heat transfer coefficient is adjusted to match the upstream temperature of the oil nozzle to be consistent with the actual temperature data; the variable of the first pressure PID controller is the oil reservoir pressure, the reading of the underground pressure transmitter is fixed, and the oil reservoir pressure is adjusted to be matched with the underground pressure to be consistent with actual pressure data; the variable of the second pressure PID controller is the wellbore roughness, the reading of the second pressure transmitter is fixed, the wellbore roughness is adjusted to be matched with the upstream pressure of the oil nozzle to be consistent with the actual data, and therefore the temperature and pressure data of the Christmas tree under the working conditions of initial starting, production increasing or restarting and the like can be simulated more accurately.

Description

Technical Field

[0001] The present invention relates to a production process of offshore oil engineering, and is a deepwater Christmas tree control system and method. Background Art

[0002] Downhole temperature and pressure transmitters are generally installed in the wellbore of deepwater oil production trees to monitor bottomhole temperature and pressure. Temperature and pressure transmitters are generally installed upstream of the oil nozzle of deepwater oil production trees to monitor the temperature and pressure of the oil production trees. Operators regularly evaluate the subsequent development potential of the reservoir and the corrosion condition of the wellbore based on the downhole temperature and pressure data and the temperature and pressure data of the oil production tree, and formulate production allocation and development plans for deepwater oil and gas fields and the frequency cycle of well repairs.

[0003] In related technologies, engineering projects or underwater digital twin system models are often used to simulate wellbore temperature, pressure, etc. However, this approach can easily lead to inaccurate model data, deviations from field data, and poor consistency. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a deepwater Christmas tree control system and method, which can accurately and real-timely calibrate the temperature and pressure loss of the wellbore online, ensure the consistency and accuracy of the model data with the field measured data, and improve the control accuracy of the deepwater Christmas tree.

[0005] In order to solve the above technical problems, the present invention provides a deepwater Christmas tree control system, comprising an oil reservoir, a wellbore, a deepwater Christmas tree, a nozzle, a subsea manifold, a submarine pipeline, a riser, and a processing platform, wherein the oil reservoir is connected to the wellbore, the wellbore is connected to the deepwater Christmas tree, the deepwater Christmas tree outlet is connected to the subsea manifold via the nozzle, the subsea manifold is connected to the submarine pipeline, and the submarine pipeline is connected to the processing platform via the riser; the system further comprises: The first pressure transmitter is used to monitor reservoir pressure and downhole pressure; a first pressure PID controller connected to the first pressure transmitter, wherein the control variable of the first pressure PID controller is the reservoir pressure, the downhole pressure value of the first pressure transmitter is fixed, and the reservoir pressure is adjusted by the first pressure PID controller so that the downhole pressure value matches the measured pressure data; A second pressure transmitter is used to monitor the wellbore roughness and the pressure upstream of the nozzle; a second pressure PID controller connected to the second pressure transmitter, wherein the control variable of the second pressure PID controller is the wellbore roughness, a pressure value upstream of the nozzle of the second pressure transmitter is fixed, and the wellbore roughness is adjusted by the second pressure PID controller so that the pressure value upstream of the nozzle matches the measured pressure data; The first temperature transmitter is used to collect reservoir temperature and downhole temperature; a first temperature PID controller connected to the first temperature transmitter, wherein the control variable of the first temperature PID controller is the oil reservoir temperature, the downhole temperature value of the first temperature transmitter is fixed, and the oil reservoir temperature is adjusted by the first temperature PID controller so that the downhole temperature value matches the field measured temperature data; The second temperature transmitter is used to collect the temperature upstream of the nozzle and the heat transfer coefficient of the wellbore; A second temperature PID controller is connected to the second temperature transmitter. The control variable of the second temperature PID controller is the wellbore heat transfer coefficient. The temperature value upstream of the nozzle is fixed. The second temperature PID controller is used to adjust the wellbore heat transfer coefficient so that the temperature value upstream of the nozzle matches the field measured temperature data.

[0006] In one embodiment of the present disclosure, the submarine pipeline is used to connect back to the processing platform, and the processing platform can separate, process and transport oil, gas and water.

[0007] In one embodiment of the present disclosure, the first temperature PID controller is used to adjust and match the reading of the first temperature transmitter; the second temperature PID controller is used to adjust and match the reading of the second temperature transmitter; The first pressure PID controller is used to adjust and match the reading of the first pressure transmitter; the second pressure PID controller is used to adjust and match the reading of the second pressure transmitter.

[0008] According to another aspect of the present disclosure, a deepwater Christmas tree control method is provided, which is applied to the deepwater Christmas tree control system according to any one of claims 1 to 3, the method comprising: S1: Establish a LedaFlow dynamic model based on reservoir temperature, reservoir pressure, wellbore parameters, the first temperature transmitter, the second temperature transmitter, the first pressure transmitter, the second pressure transmitter, and the length of the submarine pipeline; S2: controlling the reservoir temperature according to the logic of the first temperature transmitter and the first temperature PID controller, and controlling the wellbore heat transfer coefficient according to the logic of the second temperature transmitter and the second temperature PID controller; S3: controlling the reservoir pressure according to the first pressure transmitter and the first pressure PID controller logic, and controlling the wellbore roughness according to the second pressure transmitter and the second PID controller logic; S4: The parameter setting value of the first temperature PID controller is the reading of the first temperature transmitter, and the first temperature PID controller adjusts the reservoir temperature so that the downhole temperature value obtained by the reading of the first temperature transmitter matches the field measured temperature data; the parameter setting value of the second temperature PID controller is the reading of the second temperature transmitter, and the second temperature PID controller adjusts the wellbore heat transfer coefficient so that the upstream temperature value of the nozzle obtained by the reading of the second temperature transmitter matches the field measured temperature data; S5: The parameter setting value of the first pressure PID controller is the reading of the first pressure transmitter, and the first pressure PID controller adjusts the reservoir pressure so that the downhole pressure value obtained by the reading of the first pressure transmitter matches the measured pressure data; the parameter setting value of the second pressure PID controller is the reading of the second pressure transmitter, and the second pressure PID controller adjusts the wellbore roughness so that the nozzle upstream pressure value obtained by the reading of the second pressure transmitter matches the measured pressure data; S6: The LedaFlow dynamic model calculates multiple groups of readings from the first temperature transmitter and the second temperature transmitter to form temperature data of the LedaFlow dynamic model that accurately matches the field-measured temperature data; the LedaFlow dynamic model calculates multiple groups of readings from the first pressure transmitter and the second pressure transmitter to form pressure data of the LedaFlow dynamic model that accurately matches the field-measured pressure data.

[0009] In one embodiment of the present disclosure, in step S1 , a LedaFlow dynamic model is established using LedaFlow software and a LedaFlow controller.

[0010] In one embodiment of the present disclosure, in step S2, a temperature PID controller is set according to the downhole temperature value obtained by the first temperature transmitter reading and the nozzle upstream temperature value obtained by the second temperature transmitter reading.

[0011] In one embodiment of the present disclosure, in step S3, a pressure PID controller is set according to the downhole pressure value obtained by the first pressure transmitter reading and the nozzle upstream pressure value obtained by the second pressure transmitter reading.

[0012] In one embodiment of the present disclosure, the LedaFlow dynamic model in step S6 calculates at least 5 groups of the first temperature transmitter readings and multiple groups of the second temperature transmitter readings, at least 5 groups of the first pressure transmitter readings and multiple groups of the second pressure transmitter readings, to form an accurate match between the simulated system temperature and pressure data and the field measured temperature and pressure data.

[0013] The technical effect of the present invention is that the deepwater Christmas tree control system of the present invention includes an oil reservoir, a wellbore, a deepwater Christmas tree, a nozzle, a submarine pipeline, a riser and a processing platform. The oil reservoir is connected to the wellbore, the wellbore is connected to the deepwater Christmas tree, the deepwater Christmas tree outlet is connected to the submarine pipeline through the nozzle, and the submarine pipeline is connected to the processing platform through the riser; the system also includes: a first pressure transmitter for monitoring the reservoir pressure and downhole pressure; a second pressure transmitter for monitoring the wellbore roughness and the upstream pressure of the nozzle; a first pressure PID controller is connected to the first pressure transmitter; and a second pressure PID controller is connected to the second pressure transmitter. The controller is connected to the second pressure transmitter. The control variable of the first pressure PID controller is the reservoir pressure, and the control variable of the second pressure PID controller is the wellbore roughness. The downhole pressure value of the first pressure transmitter and the upstream pressure value of the nozzle of the second pressure transmitter are fixed. The two pressure PID controllers are used to adjust the reservoir pressure and the wellbore roughness so that the downhole pressure value and the upstream pressure value of the nozzle match the measured pressure data, so that the system pressure data of the LedaFlow dynamic model accurately matches the field measured pressure data; the first temperature transmitter is used to collect the reservoir temperature and the downhole temperature; the second temperature transmitter is used to collect the upstream temperature of the nozzle and the wellbore heat transfer coefficient; the first temperature PID controller is connected to the first temperature transmitter, and the second temperature PID controller is connected to the second temperature transmitter. The control variables of the two temperature PID controllers are the reservoir temperature and the wellbore heat transfer coefficient. The downhole temperature value of the first temperature transmitter and the upstream temperature value of the nozzle are fixed. The two temperature PID controllers are used to adjust the reservoir temperature and the wellbore heat transfer coefficient so that the downhole temperature value and the upstream temperature value of the deepwater oil tree nozzle match the field measured temperature data, so that The system temperature data of the LedaFlow dynamic model accurately matches the field-measured temperature data. When modeling engineering projects or underwater digital twin systems, the temperature and pressure PID controllers set on the wellbore pipeline are used to calibrate the wellbore heat transfer coefficient and roughness in real time to ensure that the simulation system data accurately matches the field-measured data. This allows for more accurate simulation of the temperature and pressure data of the Christmas tree during initial startup, production increase, or restart, optimizes the well opening procedure and time, reduces the use of thermodynamic inhibitors during the well opening process, and uses an online calibration model to analyze the impact of different wellbore structures on the temperature and pressure changes of the Christmas tree. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic structural diagram of the deepwater Christmas tree control system of the present invention; Figure 2 This is a flow chart of the deepwater Christmas tree control method of the present invention.

[0015] Description of the main numbers in the figure: 1-Oil reservoir, 2-Wellbore, 3-Deepwater Christmas tree, 4-First temperature PID controller, 5-Second temperature PID controller, 6-First pressure PID controller, 7-Second pressure PID controller, 8-Nipples, 9-Subsea manifold, 10-Subsea pipeline, 11-Riser, 12-Processing platform. DETAILED DESCRIPTION

[0016] The present invention will be further described below with reference to the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it. However, the embodiments are not intended to limit the present invention.

[0017] In related technologies, engineering projects or underwater digital twin system models are usually used to simulate wellbore temperature, pressure, etc.

[0018] Due to the influence of wellbore heat transfer and roughness, the calculated downhole temperature and pressure values ​​and the calculated temperature and pressure values ​​upstream of the deepwater oil production tree nozzle in engineering projects or underwater digital twin system models are often inconsistent with the actual temperature and pressure data measured on site. This leads to inaccurate data in the engineering development model or digital twin model, and there are certain errors with the field data. It is impossible to accurately evaluate the temperature and pressure data of the oil production tree under initial startup, production increase or restart conditions, which affects the analysis of the well opening procedure, time and the amount of thermodynamic inhibitor used during the well opening process.

[0019] Figure 1 This is a schematic diagram of the structure of the deepwater Christmas tree control system of the present invention. Figure 1 As shown, in one embodiment, a deepwater Christmas tree control system includes an oil reservoir 1, a wellbore 2, a deepwater Christmas tree 3, a nozzle 8, a subsea pipeline 10, a riser 11, and a processing platform 12. The oil reservoir 1 is connected to the wellbore 2, which is connected to the deepwater Christmas tree 3. The outlet of the deepwater Christmas tree 3 is connected to a subsea manifold 7 via the nozzle 8. The bottom end of the subsea manifold 7 is connected to a subsea pipeline 10, which is connected to the processing platform 12 via the riser 11.

[0020] In one embodiment, an oil reservoir 1 disposed at the bottom of a deepwater well is connected to the bottom end of a wellbore 2, the top of the wellbore 2 is connected to a Christmas tree 3, the liquid outlet of the Christmas tree 3 is connected to an outlet pipeline, the end of the outlet pipeline is connected to an underwater manifold 7; the bottom of the underwater manifold 7 is connected to a submarine pipeline 10, and the submarine pipeline 10 is connected to a processing platform 12 through a riser 11.

[0021] In one embodiment, a nozzle 8 is provided on the outlet pipeline. By adjusting the size of the nozzle opening, the nozzle 8 can control the pressure and flow rate of the production fluid produced by the Christmas tree 3, thereby ensuring stable production in the oil and gas field. The opening of the nozzle 8 is also known as the aperture. A wider opening increases the flow rate of the production fluid through the nozzle 8. The flow area of ​​the nozzle 8 increases with increasing diameter or opening, thereby reducing the velocity of the production fluid through the nozzle 8 and increasing the flow rate. Conversely, a smaller opening decreases the flow rate of the production fluid through the nozzle 8.

[0022] In one embodiment, the deepwater Christmas tree control system further comprises: The first pressure transmitter PT1 is used to monitor reservoir pressure and downhole pressure; A first pressure proportional-integral-differential (PID) controller 6 is connected to the first pressure transmitter PT1. The control variable of the first pressure PID controller 6 is the pressure of the reservoir 1. The downhole pressure value of the first pressure transmitter PT1 is fixed, and the pressure of the reservoir 1 is adjusted by the first pressure PID controller 6 to match the measured pressure data. The second pressure transmitter PT2 is used to monitor the roughness of the wellbore and the pressure upstream of the nozzle 8; The second pressure PID controller 7 is connected to the second pressure transmitter PT2. The control variable of the second pressure PID controller 7 is the wellbore roughness. The upstream pressure value of the nozzle of the second pressure transmitter PT2 is fixed. The second pressure PID controller 7 is used to adjust the wellbore roughness so that the upstream pressure value of the nozzle matches the measured pressure data, so that the system pressure data of the LedaFlow dynamic model accurately matches the actual measured pressure data on site. The first temperature transmitter TT1 is used to collect the temperature of the reservoir 1 and the downhole temperature; The first temperature PID controller 4 is connected to the first temperature transmitter TT1. The control variable of the first temperature PID controller 4 is the temperature of the oil reservoir 1. The downhole temperature value of the first temperature transmitter TT1 is fixed. The first temperature PID controller 4 is used to adjust the temperature of the oil reservoir 1 so that the downhole temperature value matches the field measured temperature data, so that the system temperature data of the LedaFlow dynamic model accurately matches the field measured temperature data. The second temperature transmitter TT2 is used to collect the temperature upstream of the oil nozzle 8 and the heat transfer coefficient of the wellbore; The second temperature PID controller 5 is connected to the second temperature transmitter TT2. The control variable of the second temperature PID controller 5 is the wellbore heat transfer coefficient. The temperature value upstream of the nozzle 8 is fixed. The second temperature PID controller 5 is used to adjust the wellbore heat transfer coefficient so that the temperature value upstream of the nozzle 8 matches the field measured temperature data, so that the system temperature data of the LedaFlow dynamic model accurately matches the field measured temperature data.

[0023] The first pressure transmitter PT1 is installed at the oil reservoir 1, and the second pressure transmitter PT2 is installed on the outlet pipeline upstream of the nozzle 8 to monitor the downhole pressure, reservoir pressure, nozzle upstream pressure and wellbore roughness.

[0024] The first temperature transmitter TT1 is set at the oil reservoir 1, and the second temperature transmitter TT2 is set on the outlet pipeline upstream of the oil nozzle 8 to monitor the downhole temperature, the oil reservoir 1 temperature, the temperature upstream of the oil nozzle and the wellbore heat transfer coefficient.

[0025] It should be noted that multiphase flow sensors can be used for both the temperature transmitter and the pressure transmitter, and can detect the temperature, pressure, flow, oil and gas field output, etc. of the measured production fluid.

[0026] The PID controller is an automatic controller consisting of a proportional unit P, an integral unit I, and a differential unit D. By setting the three parameters Kp, Ki, and Kd, it can be used for systems that are basically linear and whose dynamic characteristics do not change with time.

[0027] In one embodiment, the control variable of the first pressure PID controller 6 is the reservoir pressure; the control variable of the second pressure PID controller 7 is the wellbore roughness. By fixing the downhole pressure value and the pressure value upstream of the nozzle, the reservoir pressure and wellbore roughness are adjusted. The downhole pressure value and the pressure value upstream of the nozzle can be field-measured pressure data, so that the pressure reading of the LedaFlow dynamic model accurately matches the field-measured pressure data, thereby improving the effectiveness and reliability of deepwater oil production tree control.

[0028] It should be noted that the amount of data that needs to be collected for different control variables can be determined based on actual needs. The more data there is, the more detailed the classification is, and the higher the adjustment accuracy is.

[0029] In one embodiment, the control variable of the first temperature PID controller 4 is the temperature of the reservoir 1, and the control variable of the second temperature PID controller 5 is the heat transfer coefficient of the wellbore 2. By fixing the downhole temperature value and the temperature value upstream of the nozzle 8, the temperature of the reservoir 1 and the heat transfer coefficient of the wellbore 2 are adjusted. The downhole temperature value and the temperature value upstream of the nozzle 8 can be set to the actual measured temperature data on site, so that the temperature reading of the LedaFlow dynamic model accurately matches the actual measured temperature data on site.

[0030] It should be noted that the control logic of the temperature PID controller is similar to that of the pressure PID controller and will not be described in detail here.

[0031] In one embodiment, the first temperature PID controller 4 is used to adjust and match the reading of the first temperature transmitter TT1; the second temperature PID controller 5 is used to adjust and match the reading of the second temperature transmitter TT2; The first pressure PID controller 6 is used to adjust and match the reading of the first pressure transmitter PT1; the second pressure PID controller 7 is used to adjust and match the reading of the second pressure transmitter PT2.

[0032] The deepwater Christmas tree control system of the present invention utilizes temperature and pressure PID controllers installed on the wellbore pipeline to calibrate the wellbore heat transfer coefficient and roughness in real time when modeling an engineering project or underwater digital twin system. This ensures that the simulated system data accurately matches the field measured data, more accurately simulates the temperature and pressure data of the Christmas tree under conditions such as initial startup, production increase, or restart, optimizes the well opening procedure and time, reduces the use of thermodynamic inhibitors during the well opening process, and utilizes an online calibration model to analyze the impact of different wellbore structures on the temperature and pressure changes of the Christmas tree.

[0033] In one embodiment, the submarine pipeline 10 is connected back to the processing platform 12, and the processing platform 12 can separate, process and transport oil, gas and water.

[0034] The processing platform 12 can be used to separate, process and transport oil, gas and water production fluids. The processing platform 12 can be equipped with a multiphase separator, a pressure relief system, a flare system, etc., which are not limited in this disclosure.

[0035] Figure 2 This is a flow chart of the deepwater Christmas tree control method of the present invention. Figure 2 As shown, in one embodiment, a deepwater Christmas tree control method is applied to the deepwater Christmas tree control system in the above embodiment, and the method includes the following steps:

[0036] S1: Establish a LedaFlow dynamic model based on the temperature of reservoir 1, the pressure of reservoir 1, the parameters of wellbore 2, the first temperature transmitter TT1, the second temperature transmitter TT2, the first pressure transmitter PT1, the second pressure transmitter PT2, and the length of submarine pipeline 10; S2: The temperature of the reservoir 1 is logically controlled according to the first temperature transmitter TT1 and the first temperature PID controller 4, and the heat transfer coefficient of the wellbore 2 is logically controlled according to the second temperature transmitter TT2 and the second temperature PID controller 5; S3: Control the reservoir 1 pressure according to the logic of the first pressure transmitter PT1 and the first pressure PID controller 6, and control the wellbore 2 roughness according to the logic of the second pressure transmitter PT2 and the second pressure PID controller 7; S4: The parameter setting value of the first temperature PID controller 4 is the reading of the first temperature transmitter TT1. The first temperature PID controller 4 adjusts the temperature of the oil reservoir 1 so that the downhole temperature value obtained by the reading of the first temperature transmitter TT1 matches the field measured temperature data. The parameter setting value of the second temperature PID controller 5 is the reading of the second temperature transmitter TT2. The second temperature PID controller 5 adjusts the heat transfer coefficient of the wellbore 2 so that the temperature value upstream of the oil nozzle 8 obtained by the reading of the second temperature transmitter TT2 matches the field measured temperature data. S5: The parameter setting value of the first pressure PID controller 6 is the reading of the first pressure transmitter PT1. The first pressure PID controller 6 adjusts the pressure of the reservoir 1 so that the downhole pressure value obtained by the reading of the first pressure transmitter PT1 matches the measured pressure data. The parameter setting value of the second pressure PID controller 7 is the reading of the second pressure transmitter PT2. The second pressure PID controller 7 adjusts the roughness of the wellbore 2 so that the pressure value upstream of the nozzle 8 obtained by the reading of the second pressure transmitter PT2 matches the measured pressure data. S6: The LedaFlow dynamic model calculates multiple sets of readings from the first temperature transmitter TT1 and the second temperature transmitter TT2, forming temperature data of the LedaFlow dynamic model that accurately matches the field-measured temperature data; the LedaFlow dynamic model calculates multiple sets of readings from the first pressure transmitter PT1 and the second pressure transmitter PT2, forming pressure data of the LedaFlow dynamic model that accurately matches the field-measured pressure data.

[0037] In one embodiment: in step S1 , a LedaFlow dynamic model is established using LedaFlow software and a LedaFlow controller.

[0038] In one embodiment, in step S2, the first temperature PID controller 4 is set according to the downhole temperature value obtained by reading the first temperature transmitter TT1; the second temperature PID controller 5 is set according to the upstream temperature value of the nozzle 8 obtained by reading the second temperature transmitter TT2.

[0039] In one embodiment, in step S3, the first pressure PID controller 6 is set according to the downhole pressure value obtained by the reading of the first pressure transmitter PT1; the second pressure PID controller 7 is set according to the upstream pressure value of the nozzle 8 obtained by the reading of the second pressure transmitter PT2.

[0040] In one embodiment: in step S6, the LedaFlow dynamic model calculates at least 5 groups of first temperature transmitter TT1 readings and multiple groups of second temperature transmitter TT2 readings, at least 5 groups of first pressure transmitter PT1 readings and multiple groups of second pressure transmitter PT2 readings, forming a simulation system temperature and pressure data that accurately matches the field measured temperature and pressure data.

[0041] It should be noted that the implementation of the method embodiment is similar to the implementation of the system embodiment, and the similarities are not repeated here.

[0042] In an embodiment of the present invention, a LedaFlow dynamic model is established based on the reservoir 1 pressure, reservoir 1 temperature, wellbore structure, wellbore parameters, two sets of temperature transmitters, two sets of pressure transmitters, submarine pipeline 10, riser 11, etc., and two sets of temperature and pressure PID controllers are set in the deepwater oil production tree wellbore pipeline. The variable of the first temperature PID controller 4 is the temperature of the reservoir 1, and the reading of the downhole temperature transmitter is fixed. The first temperature PID controller 4 is used to adjust the temperature of the reservoir 1 to match the reading of the downhole temperature transmitter; the variable of the second temperature PID controller 5 is the wellbore heat transfer coefficient, and the reading of the temperature transmitter upstream of the deepwater oil production tree nozzle is fixed. The second temperature PID controller 5 is used to adjust the wellbore heat transfer coefficient to match the reading of the temperature transmitter upstream of the deepwater oil production tree nozzle; the control variable of the first pressure PID controller 6 is the reservoir pressure, and the downhole pressure is fixed. The first pressure PID controller 6 is used to adjust the reservoir pressure to match the downhole pressure transmitter reading. The second pressure PID controller 7 controls the wellbore roughness as the variable. The pressure transmitter reading upstream of the deepwater Christmas tree nozzle is fixed. The second pressure PID controller 7 is used to adjust the wellbore roughness to match the pressure transmitter reading upstream of the deepwater Christmas tree nozzle. When modeling an engineering project or an underwater digital twin system, the temperature and pressure PID controllers set on the wellbore pipeline are used to calibrate the wellbore heat transfer coefficient and roughness in real time to ensure that the simulation system data accurately matches the field measured data, more accurately simulate the temperature and pressure data of the Christmas tree under initial startup, production increase or restart conditions, optimize the well opening procedure and time, reduce the use of thermodynamic inhibitors during the well opening process, and use the online calibration model to analyze the impact of different wellbore structures on the temperature and pressure changes of the Christmas tree.

[0043] The above embodiments are merely preferred embodiments for the purpose of fully illustrating the present invention, and the scope of protection of the present invention is not limited thereto. Equivalent substitutions or modifications made by those skilled in the art based on the present invention are all within the scope of protection of the present invention. The scope of protection of the present invention shall be subject to the claims.

Claims

1. A deepwater Christmas tree control system, characterized in that: The system comprises an oil reservoir, a wellbore, a deepwater Christmas tree, a nozzle, a subsea manifold, a submarine pipeline, a riser and a processing platform, wherein the oil reservoir is connected to the wellbore, the wellbore is connected to the deepwater Christmas tree, the deepwater Christmas tree outlet is connected to the subsea manifold through the nozzle, the subsea manifold is connected to the submarine pipeline, and the submarine pipeline is connected to the processing platform through the riser; the system also comprises: The first pressure transmitter is used to monitor reservoir pressure and downhole pressure; a first pressure PID controller connected to the first pressure transmitter, wherein the control variable of the first pressure PID controller is the reservoir pressure, the downhole pressure value of the first pressure transmitter is fixed, and the reservoir pressure is adjusted by the first pressure PID controller so that the downhole pressure value matches the measured pressure data; A second pressure transmitter is used to monitor the wellbore roughness and the pressure upstream of the nozzle; a second pressure PID controller connected to the second pressure transmitter, wherein the control variable of the second pressure PID controller is the wellbore roughness, the nozzle upstream pressure value of the second pressure transmitter is fixed, and the wellbore roughness is adjusted by the second pressure PID controller so that the nozzle upstream pressure value matches the measured pressure data; The first temperature transmitter is used to collect reservoir temperature and downhole temperature; a first temperature PID controller connected to the first temperature transmitter, wherein the control variable of the first temperature PID controller is the oil reservoir temperature, the downhole temperature value of the first temperature transmitter is fixed, and the oil reservoir temperature is adjusted by using the first temperature PID controller so that the downhole temperature value matches the field measured temperature data; The second temperature transmitter is used to collect the temperature upstream of the oil nozzle and the heat transfer coefficient of the wellbore; The second temperature PID controller is connected to the second temperature transmitter. The control variable of the second temperature PID controller is the wellbore heat transfer coefficient. The temperature value upstream of the oil nozzle is fixed. The second temperature PID controller is used to adjust the wellbore heat transfer coefficient so that the temperature value upstream of the oil nozzle matches the field measured temperature data.

2. A deepwater Christmas tree control system according to claim 1, characterized in that: The submarine pipeline is used to connect back to the processing platform, and the processing platform can separate, process and transport oil, gas and water.

3. A deepwater Christmas tree control system according to claim 1, characterized in that: The first temperature PID controller is used to adjust and match the data of the reading of the first temperature transmitter; the second temperature PID controller is used to adjust and match the data of the reading of the second temperature transmitter; The first pressure PID controller is used to adjust and match the data of the reading of the first pressure transmitter; the second pressure PID controller is used to adjust and match the data of the reading of the second pressure transmitter.

4. A deepwater Christmas tree control method, characterized in that: Applied to the deepwater Christmas tree control system according to any one of claims 1 to 3, the method comprises: S1: Establish a LedaFlow dynamic model based on reservoir temperature, reservoir pressure, wellbore parameters, the first temperature transmitter, the second temperature transmitter, the first pressure transmitter, the second pressure transmitter, and the length of the submarine pipeline; S2: controlling the reservoir temperature according to the first temperature transmitter and the first temperature PID controller logic, and controlling the wellbore heat transfer coefficient according to the second temperature transmitter and the second temperature PID controller logic; S3: controlling the reservoir pressure according to the first pressure transmitter and the first pressure PID controller logic, and controlling the wellbore roughness according to the second pressure transmitter and the second PID controller logic; S4: The parameter setting value of the first temperature PID controller is the reading of the first temperature transmitter, and the first temperature PID controller adjusts the reservoir temperature so that the downhole temperature value obtained by the reading of the first temperature transmitter matches the field measured temperature data; the parameter setting value of the second temperature PID controller is the reading of the second temperature transmitter, and the second temperature PID controller adjusts the wellbore heat transfer coefficient so that the upstream temperature value of the oil nozzle obtained by the reading of the second temperature transmitter matches the measured temperature data; S5: The parameter setting value of the first pressure PID controller is the reading of the first pressure transmitter, and the first pressure PID controller adjusts the reservoir pressure so that the downhole pressure value obtained by the reading of the first pressure transmitter matches the measured pressure data; the parameter setting value of the second pressure PID controller is the reading of the second pressure transmitter, and the second pressure PID controller adjusts the wellbore roughness so that the nozzle upstream pressure value obtained by the reading of the second pressure transmitter matches the measured pressure data; S6: The LedaFlow dynamic model calculates multiple groups of readings from the first temperature transmitter and the second temperature transmitter, so that the temperature data of the LedaFlow dynamic model accurately matches the temperature data actually measured on site; the LedaFlow dynamic model calculates multiple groups of readings from the first pressure transmitter and the second pressure transmitter, so that the pressure data of the LedaFlow dynamic model accurately matches the pressure data actually measured on site.

5. A deepwater Christmas tree control method according to claim 4, characterized in that: In step S1, a LedaFlow dynamic model is established using LedaFlow software and a LedaFlow controller.

6. A deepwater Christmas tree control method according to claim 4, characterized in that: In step S2, a temperature PID controller is set according to the downhole temperature value obtained by the first temperature transmitter reading and the nozzle upstream temperature value obtained by the second temperature transmitter reading.

7. A deepwater Christmas tree control method according to claim 4, characterized in that: In step S3, a pressure PID controller is set according to the downhole pressure value obtained by the reading of the first pressure transmitter and the nozzle upstream pressure value obtained by the reading of the second pressure transmitter.

8. A deepwater Christmas tree control method according to claim 4, characterized in that: The LedaFlow dynamic model in step S6 calculates at least 5 groups of the first temperature transmitter readings and multiple groups of the second temperature transmitter readings, at least 5 groups of the first pressure transmitter readings and multiple groups of the second pressure transmitter readings, so as to accurately match the simulated system temperature and pressure data with the field measured temperature and pressure data.

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