Drilling parameter multi-objective optimization method based on dynamic stability constraint

Abstract

The invention belongs to the field of drilling parameter optimization, relates to a data analysis technology, is used for solving the problem that in the prior art, optimization analysis cannot be carried out on drilling parameters by combining dynamic stability analysis results, and particularly relates to a drilling parameter multi-objective optimization method based on dynamic stability constraints. Comprising the following steps: setting drilling parameters before drilling construction; stability analysis is conducted in the drilling construction process, wherein the drilling construction process is divided into a plurality of analysis time periods, drilling density data, ground pressure data and Poisson data of the analysis time periods are obtained, numerical calculation is conducted, and stability coefficients of the analysis time periods are obtained; according to the method, the construction stability in the drilling construction process can be analyzed, the drilling construction stable state in the analysis time period is evaluated according to the stability coefficient, the fluctuation coefficient is obtained after differentiation marking is conducted on the analysis time period, evaluation data is formed by combining the fluctuation coefficient with the drilling parameters in the drilling construction process, and data support is provided for optimization analysis.

Description

Technical Field

[0001] The invention belongs to the field of drilling parameter optimization and relates to data analysis technology, in particular to a drilling parameter multi-objective optimization method based on dynamic stability constraints. Background Art

[0002] Drilling stability refers to the ability of the well wall rock to remain intact and not collapse during the drilling process. It is affected by many factors, including geological conditions, drilling fluid properties and drilling parameters, and is crucial to the safety of oil and gas exploration and development. Drilling stability refers to the ability of the well wall rock to resist external forces and maintain its integrity and stability during the drilling process.

[0003] The invention patent with announcement number CN103177185B discloses a multi-objective optimization method and device for PDC drill bit drilling parameters. The multi-objective optimization model and genetic optimization algorithm for PDC drill bit drilling parameters established by the multi-objective optimization method can optimize drilling parameters according to the decision maker's wishes and various specific constraints, and has great flexibility and wide practicality; however, the multi-objective optimization method cannot optimize the drilling parameters in combination with the results of dynamic stability analysis, nor can it indent the parameter optimization range in combination with the setting parameters corresponding to the safety events, resulting in the inability to effectively control the drilling stability.

[0004] In view of the above technical problems, this application proposes a solution. Summary of the invention

[0005] The purpose of the present invention is to provide a multi-objective optimization method for drilling parameters based on dynamic stability constraints, which is used to solve the problem that the prior art cannot optimize the drilling parameters in combination with the results of dynamic stability analysis; The technical problem to be solved by the present invention is: how to provide a multi-objective optimization method for drilling parameters based on dynamic stability constraints, which can optimize and analyze the drilling parameters in combination with the results of dynamic stability analysis.

[0006] The purpose of the present invention can be achieved through the following technical solutions: The multi-objective optimization of drilling parameters based on dynamic stability constraints includes the following steps: Step 1: Setting the drilling parameter CSi before drilling construction: Retrieving the setting range SZi corresponding to the drilling parameter CSi, and randomly selecting a value from the setting range SZi to set the drilling parameter CSi; Step 2: Perform stability analysis during the drilling process: divide the drilling process into several analysis periods, obtain the drilling density data ZM, ground pressure data DY and Poisson data BS during the analysis period, and perform numerical calculations to obtain the stability coefficient WD during the analysis period; Step 3: Evaluate and analyze the overall stability of the drilling construction process: mark the analysis period as a stable period or a fluctuation period through the stability coefficient WD, mark the ratio of the number of fluctuation periods in the drilling construction process to the number of analysis periods as the fluctuation coefficient of the drilling construction process, and the fluctuation coefficient and the set drilling parameters CSi constitute the evaluation data of the drilling construction process; Step 4: When the number of completed drilling construction processes reaches L1, a multi-objective optimization analysis is performed on the drilling parameters of the drilling construction process and an optimization range YHi of the drilling parameters CSi is obtained; Step 5: Optimize the parameters of the drilling construction process according to the optimization range YHi; Step 6: Perform security event optimization analysis on the optimized data set.

[0007] Furthermore, in step 2, the process of acquiring the drilling density data ZM includes: acquiring the drilling fluid density in real time during the analysis period, retrieving the drilling fluid density range, marking the average value of the maximum and minimum values ​​of the drilling fluid density range as the density standard value, marking the absolute value of the difference between the drilling fluid density and the density standard value as the density deviation value, and marking the maximum value of the density deviation value during the analysis period as the drilling density data ZM; the process of acquiring the ground pressure data DY includes: acquiring the formation pressure in real time during the analysis period, retrieving the formation pressure range, marking the average value of the maximum and minimum values ​​of the formation pressure range as the ground pressure standard value, marking the absolute value of the difference between the formation pressure and the ground pressure standard value as the ground pressure deviation value, and marking the maximum value of the ground pressure deviation value during the analysis period as the ground pressure data DY; the Poisson data BS is the maximum value of the Poisson's ratio during the analysis period.

[0008] Furthermore, in step three, the specific process of marking the analysis period as a stable period or a fluctuating period includes: comparing the stability coefficient WD of the analysis period with the preset stability threshold WDmax: if the stability coefficient WD is less than the stability threshold WDmax, the corresponding analysis period is marked as a stable period; if the stability coefficient WD is greater than or equal to the stability threshold WDmax, the corresponding analysis period is marked as a fluctuating period.

[0009] Furthermore, in step four, the process of obtaining the optimization range YHi of the drilling parameter CSi includes: retrieving the evaluation data of all drilling construction processes, arranging the drilling construction processes in order of fluctuation coefficient from small to large to obtain a stable sequence, intercepting the first L2 drilling construction processes in the stable sequence and marking them as optimization target processes, retrieving the drilling parameter SCi setting value of the optimization target process, and the optimization range YHi of the drilling parameter SCi is constituted by the minimum and maximum values ​​of the drilling parameter SCi setting values ​​corresponding to the optimization target process; the optimization range YHi of all drilling parameters SCi constitutes an optimization data set.

[0010] Furthermore, in step five, the specific process of optimizing the parameters of the drilling construction process includes: setting the drilling parameter CSi before the drilling construction, and the setting method is: calling the optimization range YHi corresponding to the drilling parameter CSi, and randomly selecting a value from the optimization range YHi to set the drilling parameter CSi.

[0011] Furthermore, in step six, the specific process of performing security event optimization analysis on the optimized data set includes: when a security event occurs, the value of the drilling parameter CSi set in the current drilling construction process is retrieved and marked as the event setting value SDi, and it is determined whether the event setting value SDi is within the optimization range YHi of the corresponding drilling parameter CSi: if not, no processing is performed; if so, an event influence range YXi is generated for the drilling parameter CSi; when the value of the drilling parameter CSi is subsequently set, if the value randomly selected from the optimization range YHi is within the event influence range YXi, the value of the drilling parameter CSi is reselected.

[0012] Furthermore, the generation process of the event influence range YXi of the drilling parameter CSi includes: the event setting high value SDid and the event setting low value SDix are obtained by the formulas SDid=t1×SDi and SDix=t2×SDi, wherein t1 and t2 are both proportional coefficients, and 0.95≤t1≤0.98, 1.02≤t2≤1.05; the event setting high value SDid and the event setting low value SDix constitute the event influence range YXi of the drilling parameter CSi.

[0013] The present invention has the following beneficial effects: Through stability analysis, the construction stability of the drilling construction process can be analyzed. Multiple stability parameters are collected in different time periods for comprehensive analysis and calculation to obtain the stability coefficient. The drilling construction stability state of the analysis period is evaluated according to the stability coefficient. The fluctuation coefficient is obtained after differential marking of the analysis period. The evaluation data is formed in combination with the drilling parameters of the drilling construction process to provide data support for optimization analysis. The optimization analysis module can be used to perform multi-objective optimization analysis on the drilling parameters of the drilling construction process. After intercepting the stable sequence, the optimization range is formed according to the drilling parameters of the optimization target process. Then, the drilling parameters of the subsequent drilling construction process are set within the optimization range through the optimization setting process to improve the stability of the drilling construction. The event optimization module can be used to perform safety event optimization analysis on the optimized data set, perform numerical processing on the drilling parameters corresponding to the drilling construction process where the safety event occurred, and obtain the event impact range. Then, the drilling parameters are set in combination with the optimization range and the event impact range, and the optimization range is further indented to reduce the probability of safety accidents. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. 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 paying creative work.

[0015] Figure 1 This is a flow chart of a method according to Embodiment 1 of the present invention; Figure 2 This is a system block diagram of Embodiment 2 of the present invention. DETAILED DESCRIPTION

[0016] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0017] Embodiment 1: Figure 1 As shown, the multi-objective optimization method of drilling parameters based on dynamic stability constraints includes the following steps: Step 1: Before drilling construction, the drilling parameters CSi are set, i=1, 2, ..., n, n is a positive integer, and the drilling parameters CSi include drilling pressure, rotation speed, pump volume, pump pressure and pump rate, etc. The setting method is: call the setting range SZi corresponding to the drilling parameter CSi, and randomly select a value from the setting range SZi to set the drilling parameter CSi; Step 2: Perform stability analysis during the drilling construction process: divide the drilling construction process into several analysis periods, and obtain the drilling density data ZM, ground pressure data DY and Poisson data BS of the analysis period; the process of obtaining the drilling density data ZM includes: obtaining the drilling fluid density in real time during the analysis period, calling the drilling fluid density range, marking the average value of the maximum and minimum values ​​of the drilling fluid density range as the density standard value, marking the absolute value of the difference between the drilling fluid density and the density standard value as the density deviation value, and marking the maximum value of the density deviation value in the analysis period as the drilling density data ZM; the process of obtaining the ground pressure data DY includes: obtaining the formation pressure in real time during the analysis period, calling the formation pressure range, and marking the average value of the maximum and minimum values ​​of the formation pressure range as the ground pressure The standard value is used to mark the absolute value of the difference between the formation pressure and the standard value of the ground pressure as the ground pressure deviation value, and the maximum value of the ground pressure deviation value in the analysis period is marked as the ground pressure data DY; the Poisson data BS is the maximum value of the Poisson ratio in the analysis period; the stability coefficient WD of the analysis period is obtained by the formula WD=k1×ZM+k2×DY+k3×BS, where k1, k2 and k3 are all proportional coefficients, and k1>k2>k3>1; multiple stability parameters are collected in different time periods for comprehensive analysis and calculation to obtain the stability coefficient, and the stable state of the drilling construction in the analysis period is evaluated according to the stability coefficient. After differential marking of the analysis period, the fluctuation coefficient is obtained, and the evaluation data is formed in combination with the drilling parameters of the drilling construction process to provide data support for optimization analysis; The Jacobian matrix algorithm is used to verify and analyze the drilling construction stability state assessment results during the analysis period: the Jacobian matrix can be used to analyze the stability of the system; specifically, by calculating the eigenvalues ​​of the Jacobian matrix, the eigenvalue spectrum of the system can be obtained, thereby understanding the stability of the system. When the real parts of the eigenvalues ​​are all less than zero, the system is in a stable state; and when there are eigenvalues ​​whose real parts are greater than zero, the system is in an unstable state; when the verification results of the Jacobian matrix are inconsistent with the drilling construction stability detection results, the drilling density data ZM, ground pressure data DY and Poisson data BS are collected again, and the stability coefficient WD is calculated; In vector calculus, the Jacobian matrix is ​​a matrix in which the first-order partial derivatives are arranged in a certain way. Its determinant is called the Jacobian determinant. The importance of the Jacobian matrix lies in that it reflects the optimal linear approximation of a differentiable equation to a given point. Step 3: Evaluate and analyze the overall stability of the drilling construction process: Compare the stability coefficient WD of the analysis period with the preset stability threshold WDmax. If the stability coefficient WD is less than the stability threshold WDmax, mark the corresponding analysis period as a stable period. If the stability coefficient WD is greater than or equal to the stability threshold WDmax, mark the corresponding analysis period as a fluctuating period, and mark the ratio of the number of fluctuating periods in the drilling construction process to the analysis quantity as the fluctuation coefficient of the drilling construction process. The evaluation data of the drilling construction process is composed of the fluctuation coefficient and the set drilling parameters CSi. Step 4: When the number of completed drilling construction processes reaches L1, where L1 is a numerical constant and the specific value of L1 is set by the management personnel themselves; conduct multi-objective optimization analysis on the drilling parameters of the drilling construction process: Retrieve the evaluation data of all drilling construction processes, arrange the drilling construction processes in ascending order of the fluctuation coefficient to obtain a stable sequence, intercept the first L2 drilling construction processes in the stable sequence and mark them as the optimization target processes, where L2 is a numerical constant and the specific value of L2 is set by the management personnel themselves, and L2 < L1; Retrieve the set values of the drilling parameters SCi of the optimization target processes, and form the optimization range YHi of the drilling parameters SCi from the minimum and maximum values of the set values of the drilling parameters SCi corresponding to the optimization target processes. The optimization data set is composed of the optimization ranges YHi of all the drilling parameters SCi. After intercepting the stable sequence, form the optimization range according to the drilling parameters of the optimization target processes, and then set the drilling parameters of the subsequent drilling construction processes within the optimization range through the optimization setting process to improve the stability of the drilling construction. Step 5: Optimize the setting of the parameters of the drilling construction process: Set the drilling parameters CSi before the drilling construction. The setting method is: Retrieve the corresponding optimization range YHi of the drilling parameters CSi, and randomly select a value from the optimization range YHi for the setting of the drilling parameters CSi. Step 6: Perform safety event optimization analysis on the optimized data set: When a safety event occurs, the safety event includes drill bit breakage, drill bit sticking, serious well collapse, blowout, etc.; retrieve the value of the drilling parameter CSi set during the drilling construction process and mark it as the event setting value SDi, and determine whether the event setting value SDi is within the optimization range YHi of the corresponding drilling parameter CSi: if not, no processing is performed; if so, the event setting high value SDid and event setting low value SDix are obtained through the formula SDid=t1×SDi and SDix=t2×SDi, where t1 and t2 are both proportional coefficients, and 0.95≤t1≤0. 98, 1.02≤t2≤1.05; the event setting high value SDid and the event setting low value SDix constitute the event influence range YXi of the drilling parameter CSi; when the numerical value of the drilling parameter CSi is subsequently set, if the value randomly selected from the optimization range YHi is within the event influence range YXi, the numerical value of the drilling parameter CSi is reselected; the drilling parameters corresponding to the drilling construction process where the safety incident occurs are numerically processed to obtain the event influence range, and then the drilling parameters are set in combination with the optimization range and the event influence range, and the optimization range is further indented to reduce the probability of safety accidents.

[0018] Embodiment 2: Figure 2 As shown, the multi-objective optimization system of drilling parameters based on dynamic stability constraints includes a parameter setting module, a stability analysis module, an evaluation analysis module, an optimization analysis module, an optimization setting module and an event optimization module; The parameter setting module is used to set the drilling parameters CSi before drilling construction; The stability analysis module is used to perform stability analysis during the drilling construction process and obtain the stability coefficient WD of the drilling construction process; The evaluation and analysis module is used to evaluate and analyze the overall stability of the drilling construction process and obtain the fluctuation coefficient of the drilling construction process; The optimization analysis module is used to perform multi-objective optimization analysis on the drilling parameters of the drilling construction process based on the evaluation data of the drilling construction process; The optimization setting module is used to optimize the parameters of the drilling construction process through the optimization range YHi; The event optimization module is used to perform security event optimization analysis on the optimized data set and obtain the event impact range YXi. The event impact range YXi can be used to indent the selected interval of the optimization range YHi.

[0019] The multi-objective optimization method of drilling parameters based on dynamic stability constraints, when working, sets the drilling parameter CSi before drilling construction, randomly selects values ​​from the setting range SZi to set the drilling parameter CSi, divides the drilling construction process into several analysis periods, obtains the drilling density data ZM, ground pressure data DY and Poisson data BS of the analysis period and performs numerical calculation to obtain the stability coefficient WD, marks the analysis period as a stable period or a fluctuation period by the stability coefficient WD, marks the ratio of the number of fluctuation periods in the drilling construction process to the number of analysis periods as the fluctuation coefficient of the drilling construction process, arranges the drilling construction processes in the order of fluctuation coefficient from small to large to obtain a stable sequence, intercepts the front L2 drilling construction processes in the stable sequence and marks them as optimization target processes, generates the optimization range YHi according to the setting value of the drilling parameter CSi of the optimization target process, obtains the corresponding event influence range YXi when a safety event occurs, and selects the setting value of the drilling parameter CSi in combination with the optimization range YHi and the event influence range YXi.

[0020] The above contents are merely examples and explanations of the structure of the present invention. The technicians in this technical field may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the structure of the invention or exceed the scope defined by the claims, they should all fall within the protection scope of the present invention.

[0021] The above formulas are obtained by collecting a large amount of data for software simulation and selecting a formula close to the real value. The coefficients in the formula are set by technicians in this field according to the actual situation; for example: formula WD=k1×ZM+k2×DY+k3×BS; technicians in this field collect multiple groups of sample data and set corresponding stability coefficients for each group of sample data; substitute the set stability coefficients and the collected sample data into the formula, any three formulas constitute a three-variable linear equation group, screen the calculated coefficients and take the average, and obtain the values ​​of k1, k2 and k3 as 3.52, 2.63 and 2.12 respectively; The size of the coefficient is to quantify each parameter to obtain a specific value for subsequent comparison. The size of the coefficient depends on the amount of sample data and the initial setting of the corresponding stability coefficient for each set of sample data by technical personnel in this field; as long as it does not affect the proportional relationship between the parameter and the quantified value, such as the stability coefficient is proportional to the value of the drilling density data.

[0022] In the description of this specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0023] The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to only specific implementation methods. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A multi-objective optimization method for drilling parameters based on dynamic stability constraints, characterized in that: The following steps are involved: Step 1: Setting the drilling parameter CSi before drilling construction: Retrieving the setting range SZi corresponding to the drilling parameter CSi, and randomly selecting a value from the setting range SZi to set the drilling parameter CSi; Step 2: Perform stability analysis during the drilling process: divide the drilling process into several analysis periods, obtain the drilling density data ZM, ground pressure data DY and Poisson data BS during the analysis period, and perform numerical calculations to obtain the stability coefficient WD during the analysis period; Step 3: Evaluate and analyze the overall stability of the drilling construction process: mark the analysis period as a stable period or a fluctuation period through the stability coefficient WD, mark the ratio of the number of fluctuation periods in the drilling construction process to the number of analysis periods as the fluctuation coefficient of the drilling construction process, and the fluctuation coefficient and the set drilling parameters CSi constitute the evaluation data of the drilling construction process; Step 4: When the number of completed drilling construction processes reaches L1, a multi-objective optimization analysis is performed on the drilling parameters of the drilling construction process and an optimization range YHi of the drilling parameters CSi is obtained; Step 5: Optimize the parameters of the drilling construction process according to the optimization range YHi; Step 6: Perform security event optimization analysis on the optimized data set.

2. The multi-objective optimization method for drilling parameters based on dynamic stability constraints according to claim 1 is characterized in that: In step 2, the process of obtaining the drilling density data ZM includes: obtaining the drilling fluid density in real time during the analysis period, retrieving the drilling fluid density range, marking the average value of the maximum and minimum values ​​of the drilling fluid density range as the density standard value, marking the absolute value of the difference between the drilling fluid density and the density standard value as the density deviation value, and marking the maximum value of the density deviation value during the analysis period as the drilling density data ZM; the process of obtaining the ground pressure data DY includes: obtaining the formation pressure in real time during the analysis period, retrieving the formation pressure range, marking the average value of the maximum and minimum values ​​of the formation pressure range as the ground pressure standard value, marking the absolute value of the difference between the formation pressure and the ground pressure standard value as the ground pressure deviation value, and marking the maximum value of the ground pressure deviation value during the analysis period as the ground pressure data DY; the Poisson data BS is the maximum value of the Poisson's ratio during the analysis period.

3. The multi-objective optimization method for drilling parameters based on dynamic stability constraints according to claim 2 is characterized in that: In step three, the specific process of marking the analysis period as a stable period or a fluctuating period includes: comparing the stability coefficient WD of the analysis period with the preset stability threshold WDmax: if the stability coefficient WD is less than the stability threshold WDmax, the corresponding analysis period is marked as a stable period; if the stability coefficient WD is greater than or equal to the stability threshold WDmax, the corresponding analysis period is marked as a fluctuating period.

4. The multi-objective optimization method for drilling parameters based on dynamic stability constraints according to claim 3 is characterized in that: In step 4, the process of obtaining the optimization range YHi of the drilling parameter CSi includes: retrieving the evaluation data of all drilling construction processes, arranging the drilling construction processes in order of fluctuation coefficient from small to large to obtain a stable sequence, intercepting the first L2 drilling construction processes in the stable sequence and marking them as optimization target processes, retrieving the drilling parameter SCi setting value of the optimization target process, and the minimum and maximum values ​​of the drilling parameter SCi setting values ​​corresponding to the optimization target process constitute the optimization range YHi of the drilling parameter SCi; the optimization range YHi of all drilling parameters SCi constitutes an optimization data set.

5. The multi-objective optimization method for drilling parameters based on dynamic stability constraints according to claim 4 is characterized in that: In step five, the specific process of optimizing the parameters of the drilling construction process includes: setting the drilling parameter CSi before the drilling construction, the setting method is: calling the optimization range YHi corresponding to the drilling parameter CSi, and randomly selecting a value from the optimization range YHi to set the drilling parameter CSi.

6. The multi-objective optimization method for drilling parameters based on dynamic stability constraints according to claim 5, characterized in that: In step six, the specific process of performing security event optimization analysis on the optimized data set includes: when a security event occurs, the value of the drilling parameter CSi set in the current drilling construction process is retrieved and marked as the event setting value SDi, and it is determined whether the event setting value SDi is within the optimization range YHi of the corresponding drilling parameter CSi: if not, no processing is performed; if so, an event influence range YXi is generated for the drilling parameter CSi; when the value of the drilling parameter CSi is subsequently set, if the value randomly selected from the optimization range YHi is within the event influence range YXi, the value of the drilling parameter CSi is reselected.

7. The multi-objective optimization method for drilling parameters based on dynamic stability constraints according to claim 6, characterized in that: The generation process of the event influence range YXi of the drilling parameter CSi includes: the event setting high value SDid and the event setting low value SDix are obtained by the formulas SDid=t1×SDi and SDix=t2×SDi, wherein t1 and t2 are both proportional coefficients, and 0.95≤t1≤0.98, 1.02≤t2≤1.05; the event setting high value SDid and the event setting low value SDix constitute the event influence range YXi of the drilling parameter CSi.

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