CN-122014181-A - Layered water injection regulation and control system and method for water injection well

CN122014181ACN 122014181 ACN122014181 ACN 122014181ACN-122014181-A

Abstract

The invention relates to the field of oilfield water injection development, and provides a layered water injection regulation and control system and method of a water injection well, wherein the layered water injection regulation and control system comprises the steps of firstly acquiring historical production parameter data of different types of water injection wells, and constructing stratum parameter confidence factors representing real response characteristics of stratum; the statistical characteristics of the historical data are corrected by utilizing the confidence factors, so that a production parameter weight comparison relation is constructed, then real-time production parameter data are acquired, the lifting and controlling properties of all layers of sections are identified by combining the weight comparison relation, finally, the target water distribution amount is calculated based on the identification result, and layered regulation and control are implemented by adjusting the opening degree or injection pressure of the water distributor. The invention solves the problem of inaccurate judgment of the lifting and control property caused by data interference in the traditional single-factor analysis of variance method, and improves the accuracy and effectiveness of the layered injection allocation of the water injection well.

Inventors

XUAN YINGLONG
CHEN LEI
JIN XIANGAO
JIA XUEYAN
YUAN YUAN
CAO JINFENG
ZHANG GUOJUN
CHEN MO

Assignees

大庆油田有限责任公司
中国石油天然气股份有限公司

Dates

Publication Date: 20260512
Application Date: 20260224

Claims (13)

1. The method for regulating and controlling the separated layer water injection of the water injection well is characterized by comprising the following steps of: Acquiring different types of historical production parameter data of a water injection well; Constructing a stratum parameter confidence factor of each data point except for the control type data in the historical production parameter data, wherein the stratum parameter confidence factor is used for representing the credibility of the corresponding data point for reflecting the true response characteristics of the stratum; Correcting the statistical characteristics of the historical production parameter data by using the stratum parameter confidence factors to obtain corrected statistical characteristics of the historical production parameter data, and constructing a production parameter weight comparison relation based on the corrected statistical characteristics; Acquiring different types of real-time production parameter data of a water injection well to be regulated, comparing the real-time production parameter data with historical production parameter data, and identifying the lifting and control properties of each layer section of the water injection well to be regulated by combining the comparison relation of the production parameter weights; and calculating target water distribution amount of each layer section of the water injection well to be regulated and controlled based on the identified lifting and controlling property, and carrying out layered water injection regulation and control on the water injection well according to the target water distribution amount.
2. The method for regulating and controlling the stratified water injection of a water injection well as claimed in claim 1, wherein the process for obtaining the historical production parameter data comprises the following steps: Collecting different types of production parameters of the water injection well according to the set frequency, and obtaining different types of original production parameter data of the water injection well in a past set time period, wherein the original production parameter data at least comprise lifting and controlling properties of a water injection well interval, daily liquid production, daily oil production, daily water production, water content, stratum pressure and liquid production intensity; and normalizing the production parameter data except for the lifting and controlling properties of the water injection well interval in the original production parameter data, thereby obtaining the historical production parameter data of different types of water injection wells.
3. The method of claim 1, wherein said constructing a formation parameter confidence factor for each data point of the historical production parameter data other than the control type data comprises: Based on the control property data, acquiring historical production parameter data of the same control property class in the same interval as an analysis production parameter data set, and determining the intra-class deviation degree of each data point in the historical production parameter data based on the difference between each data point in the historical production parameter data and other data points in the analysis production parameter data set where each data point is located; Determining relevant historical production parameter data of the random historical production parameter data, and determining inter-class coupling deviation corresponding to each data in the historical production parameter data based on correlation between a local data segment where each data point in the historical production parameter data is located and a corresponding local data segment in the relevant historical production parameter data; and calculating a stratum parameter confidence factor of each data point in the historical production parameter data based on the intra-class deviation degree and the inter-class coupling deviation, wherein the stratum parameter confidence factor and the intra-class deviation degree are in a negative correlation, and the stratum parameter confidence factor and the inter-class coupling deviation are in a negative correlation.
4. A method of zonal injection control for a water injection well according to claim 3, wherein said calculating an intra-class deviation for each data point comprises: for any data point in the historical production parameter data, acquiring the same-class data sequence which is continuous in time in the analysis production parameter data set; Determining the length of the continuous same-category data sequence: If the length is smaller than a preset threshold value, calculating the absolute value of the difference value of the data point and all data means in the same-class data sequence, and taking the absolute value of the difference value as the intra-class deviation degree of the data point; if the length is greater than or equal to the preset threshold, defining a plurality of analysis time windows with different lengths on the continuous same-category data sequence, and acquiring a subsequence corresponding to each analysis time window; For the subsequence corresponding to each analysis time window, calculating the absolute value of the difference between the data point and all the data means in the subsequence to obtain a corresponding time sequence deviation degree; and calculating the average value of the time sequence deviation degrees corresponding to all the time windows, and taking the average value as the intra-class deviation degree of the data point.
5. A method of zonal injection control of a water injection well according to claim 3, wherein said determining historical production parameter data associated with said arbitrary historical production parameter data comprises: Calculating pearson correlation coefficients between different production parameter data sequences; and recording any two kinds of production parameter data with absolute values of the pearson correlation coefficients larger than a preset threshold value as correlated historical production parameter data.
6. A method of zonal injection control of a water injection well according to claim 3, wherein said calculating an inter-class coupling offset from associated production parameter data comprises: For any data point in the historical production parameter data, constructing a time window with preset length containing the data point, and calculating the difference value between each data point and the data point in the time window of the historical production parameter data to obtain a time neighborhood difference value sequence of the data point; Calculating the difference degree between the time neighborhood difference value sequence of the arbitrary data point and the time neighborhood difference value sequence of the simultaneous data point in the related historical production parameter data; and determining the inter-class coupling deviation of any data point based on the corresponding difference degrees of all the related historical production parameter data.
7. A method of stratified charge control for a water injection well as claimed in claim 3, wherein said calculating a formation parameter confidence factor for each data point in said historical production parameter data based on said intra-class bias and inter-class coupling bias comprises: carrying out weighted fusion on the intra-class deviation degree and the inter-class coupling deviation to obtain a comprehensive deviation degree; and carrying out negative correlation normalization on the comprehensive deviation degree to obtain stratum parameter confidence factors of each data point.
8. The method for regulating and controlling the stratified water injection of a water injection well according to claim 1, wherein the correcting the statistical features of the historical production parameter data by using the formation parameter confidence factor to obtain corrected statistical features of different types of historical production parameter data comprises: Taking stratum parameter confidence factors corresponding to each data point as weights, and calculating a weighted average of the historical production parameter data to obtain an average correction result; and calculating the statistical characteristics in the single-factor analysis of variance based on the mean value correction result to obtain corrected statistical characteristics.
9. The method for regulating and controlling the stratified water injection of a water injection well according to claim 1, wherein the step of constructing the production parameter weight comparison relation based on the statistical characteristics comprises the following steps: f values and contribution degrees of all production parameters are extracted from the corrected statistical characteristics based on single-factor analysis of variance; Calculating the comprehensive score of each production parameter based on the F value and the contribution degree of each production parameter; And constructing a control property judgment matrix according to the comprehensive score difference between different production parameters, wherein the element values in the control property judgment matrix are determined by the ratio of the comprehensive scores of the corresponding production parameters.
10. The method for regulating and controlling the stratified water injection of the water injection well according to claim 1, wherein the identifying the lifting and controlling property of each layer section of the water injection well to be regulated and controlled comprises the following steps: Determining weight coefficients corresponding to the real-time production parameters based on the production parameter weight comparison relation; Comparing the real-time production parameter data with the historical production parameter data of each lifting property category based on the weight coefficient to obtain the membership degree of each layer section belonging to different lifting property categories; and determining the lifting and controlling property category of each layer section according to the maximum membership principle.
11. The method for regulating and controlling the stratified water injection of the water injection well according to claim 1, wherein the calculating the target water distribution amount of each layer section of the water injection well to be regulated and controlled based on the identified lifting and controlling property comprises the following steps: based on Darcy's law and material balance principle, establishing mathematical model reflecting the relation between the interval pressure and water injection amount and creating pressure-water injection amount relation plate; and inquiring and determining the target water distribution amount of each layer section according to the lifting and controlling property identification result of each layer section and the current stratum pressure based on the pressure-water injection amount relation plate.
12. The method for regulating and controlling the stratified water injection of the water injection well according to claim 1, wherein the regulating and controlling the stratified water injection of the water injection well according to the target water distribution amount comprises the following steps: And adjusting the opening degree or injection pressure of the water distributor, and adjusting the actual water injection quantity of each layer section to the target water distribution quantity.
13. A system for regulating and controlling the stratified water injection of a water injection well, comprising a memory, a processor and a computer program stored in the memory and operable on the processor, wherein the processor, when executing the computer program, performs the steps of a method for regulating and controlling the stratified water injection of a water injection well as claimed in any one of claims 1 to 12.

Description

Layered water injection regulation and control system and method for water injection well Technical Field The invention relates to the technical field of oilfield water injection development, in particular to a layered water injection regulation and control system and method for a water injection well. Background In China, the oil fields mainly comprise heterogeneous and multi-oil layers, the permeability between different layers of the oil fields and even between plane layers of the oil fields is different, and water injection development is an effective method for improving the high yield of the oil fields. The conventional water injection method has the advantages that the water injection utilization rate is low and the displacement effect is poor due to different permeability of each layer, and the separate layer water injection adopts the packer to separate the oil layers with larger difference for separate layer water distribution, so that the effects of adjusting the water injection contradiction in the layers and increasing the crude oil extraction rate of the oil layers can be achieved. As the oil field enters the ultra-high water-containing period, the number of layers in the water injection well of the separated layer water injection becomes more and finer, and the interlayer contradiction increases. The traditional separate layer water injection regulation and control method is difficult to accurately consider the influence of the layer section property combination and the water distribution amount on the water injection effect of the whole well, so that the water injection amount distribution is unreasonable, and the oil reservoir development efficiency is influenced. Therefore, a scientific and systematic method for judging the layer section lifting and controlling properties is needed to improve the accuracy and effectiveness of the water injection well layered injection. Disclosure of Invention The invention provides a layered water injection regulation and control system and a method of a water injection well, which are used for solving the problem of unreasonable water injection rate distribution caused by inaccurate judgment caused by data interference in water injection well interval lifting and control property judgment by a traditional single-factor analysis of variance method, wherein the adopted technical scheme is as follows: the invention relates to a layered water injection regulation and control method of a water injection well, which comprises the following steps: In a first aspect, an embodiment of the present invention provides a method for controlling stratified water injection in a water injection well, the method comprising the steps of: Acquiring different types of historical production parameter data of a water injection well; Constructing a stratum parameter confidence factor of each data point except for the control type data in the historical production parameter data, wherein the stratum parameter confidence factor is used for representing the credibility of the corresponding data point for reflecting the true response characteristics of the stratum; Correcting the statistical characteristics of the historical production parameter data by using the stratum parameter confidence factors to obtain corrected statistical characteristics of the historical production parameter data, and constructing a production parameter weight comparison relation based on the corrected statistical characteristics; Acquiring different types of real-time production parameter data of a water injection well to be regulated, comparing the real-time production parameter data with historical production parameter data, and identifying the lifting and control properties of each layer section of the water injection well to be regulated by combining the comparison relation of the production parameter weights; and calculating target water distribution amount of each layer section of the water injection well to be regulated and controlled based on the identified lifting and controlling property, and carrying out layered water injection regulation and control on the water injection well according to the target water distribution amount. Preferably, the process of obtaining the historical production parameter data includes: Collecting different types of production parameters of the water injection well according to the set frequency, and obtaining different types of original production parameter data of the water injection well in a past set time period, wherein the original production parameter data at least comprise lifting and controlling properties of a water injection well interval, daily liquid production, daily oil production, daily water production, water content, stratum pressure and liquid production intensity; and normalizing the production parameter data except for the lifting and controlling properties of the water injection well interval in the original production parameter data, thereby ob