Photovoltaic power generation and rod pumped well group peak shifting operation coupling control method and system

Abstract

The invention discloses a photovoltaic power generation and rod-pumped well group peak shifting operation coupling control method and system, and belongs to the technical field of rod-pumped well group peak shifting operation, and the method comprises the following steps: 1, building a single well interval pumping system in a rod-pumped well group according to a liquid outlet rule when each well in the rod-pumped well group is opened and a liquid level recovery rule after the well is closed; step 2, simulating daily generation power curves under different photovoltaic installed power conditions according to well site light resource conditions, and selecting photovoltaic installed capacity adaptive to sequential control power consumption of the pumping well group; 3, a pumping unit well group well opening and closing system matched with the photovoltaic real-time power generation amount is established, and a zero-carbon oil extraction scheme with the space-time change rule and the oil well liquid supply rule complementary is formed. The problem that a current pumping unit photovoltaic power generation system needs energy storage or needs power grid cooperation peak regulation is solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of staggered peak operation of a pumping well group, and in particular relates to a photovoltaic power generation and staggered peak operation coupling control method and system for a pumping well group. Background Art

[0002] With the development of oil fields, oil wells will experience insufficient fluid supply in the middle and late stages of production. In order to prevent the pump from pumping out empty and ensure the working efficiency of the pumping unit, intermittent pumping is often used for such oil wells. Currently, the commonly used intermittent pumping technologies include soft start intelligent intermittent pumping, variable frequency control non-stop intermittent pumping, etc. Intermittent pumping has achieved certain energy-saving effects for oil wells with insufficient fluid supply. However, due to the low fluid production of intermittent pumping wells, the electricity type is still all thermal power, and the carbon emission intensity per unit of fluid is high. Therefore, people have carried out electric photovoltaic substitution applications for intermittent pumping wells with pumping units.

[0003] When using photovoltaics to supply green electricity to the wells between pumping units, photovoltaic power generation is discontinuous and unstable. Its power generation law is different from the oil well fluid supply law, making it difficult to match the power consumption of the pumping unit with photovoltaic power generation and to achieve a balance between power supply and demand. Therefore, supporting energy storage or peak load regulation with the power grid is required to ensure the normal operation of the pumping unit. However, for the photovoltaic + energy storage mode, the use of energy storage batteries leads to a significant increase in investment costs. For the photovoltaic + grid power mode, not only is the amount of clean electricity substitution low, but this mode cannot be promoted and applied to remote wells without grid power coverage. Summary of the invention

[0004] The present invention provides a method and system for coupling control of photovoltaic power generation and staggered operation of a group of pumping wells. Through multi-well coordination, photovoltaic power generation is matched with electricity consumption of a group of pumping wells, solving the problem that the current photovoltaic power generation system of the pumping wells needs energy storage or grid cooperation for peak regulation.

[0005] In order to achieve the above object, the present invention adopts the following technical solution:

[0006] A method for coupling control of photovoltaic power generation and peak-shifting operation of a pumping well group comprises the following steps:

[0007] Step 1: Establish a single well inter-pumping system within the pumping well group based on the liquid discharge law of each well when it is opened and the liquid level recovery law after the well is closed;

[0008] Step 2: According to the light resource conditions of the well site, simulate the daily power curve of different photovoltaic installed power conditions, and select the photovoltaic installed capacity that is suitable for the power consumption of the timing control of the oil pumping well group;

[0009] Step 3: Establish a system for switching on and off pumping wells that matches the real-time photovoltaic power generation, and form a zero-carbon oil production plan that complements the temporal and spatial variation laws with the oil well fluid supply laws.

[0010] Furthermore, in step 1, the oil pumping well group has relatively poor fluid supply capacity and low oil pumping efficiency.

[0011] Furthermore, step 1 includes the following steps:

[0012] S1.1. Calculate the fullness of the downhole oil pump;

[0013] S21. Formulate a single well inter-pumping system based on the changing law of the filling degree of the oil pump;

[0014] When the oil pump is running continuously, the fullness of the oil pump is calculated once at an interval set time using the collected indicator diagram. If the initial calculated fullness of the oil pump is lower than the first set value, the unit is shut down and waits for the oil well to recover the liquid level. After the initial calculated fullness of the oil pump is higher than the first set value, the fullness of the oil pump is calculated continuously at set intervals until the calculated fullness of the oil pump is lower than the second set value. The continuous operation time of the oil pumping is recorded as the well opening time of the intermittent pumping system, and the second set value is less than the first set value.

[0015] Furthermore, in step S1.1, the fullness of the downhole oil pump is calculated using the dynamometer diagram.

[0016] Furthermore, the degree of filling of the oil well pump is calculated as the ratio η of the volume of liquid entering the oil well pump and the volume of liquid released by the plunger during the upstroke, and the calculation formula is:

[0017]

[0018] Where η 泵 is the filling degree of the oil pump, L1 is the effective liquid inlet stroke, and L2 is the effective stroke. 6. A photovoltaic power generation and oil pumping well group staggered operation coupling control method according to claim 1, characterized in that in step 2, the photovoltaic installed capacity is calculated by the following formula:

[0019]

[0020] Where P is the installed capacity of photovoltaic array; Pv is the capacity ratio of photovoltaic system; Ri —Rated power of the motor used for the i-th well in the pumping well group; R Li —Load rate of the motor used for the i-th well in the pumping well group; α i —Daily opening time of the i-th well in the pumping well group; T U —Annual equivalent utilization hours of photovoltaic power generation system; η—comprehensive system efficiency of photovoltaic power station.

[0021] Further, step 3 includes the following steps:

[0022] Based on the formation fluid supply capacity, oil well lifting capacity and photovoltaic power generation capacity, with the constraints of maintaining production and ensuring the starting current of the motor, and the goal of minimizing the abandonment rate of light, under the premise of ensuring the production of the oil wells, more wells will be started when the photovoltaic power generation power is high, and more wells will be stopped when the photovoltaic power generation power is low, so as to match the oil well start-stop system with the photovoltaic power generation power.

[0023] A photovoltaic power generation and pumping well group peak shifting operation coupling control system, comprising:

[0024] MPPT controller, used to maximize the output power of photovoltaic modules;

[0025] Inverter module, used to convert the direct current output by the photovoltaic module into alternating current;

[0026] Output filter module, used for filtering AC power;

[0027] The electrical parameter monitoring module of the oil pump is used to monitor the electrical parameters of the oil pump;

[0028] The PLC controller is used to establish a well opening and closing system for the well group of the pumping units that matches the real-time photovoltaic power generation according to the electrical parameters of the pumping units;

[0029] The intermittent pumping control module is used to control the pumping units according to the switching well system of the pumping well group.

[0030] A computer device comprises an electrically connected memory and a processor, wherein the memory stores a computer program that can be run on the processor, and when the processor executes the computer program, the steps of the above control method are implemented.

[0031] A computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the above-mentioned control method are implemented.

[0032] Compared with the prior art, the present invention has at least the following beneficial technical effects:

[0033] The method described in the present invention is based on the peak-shifting lifting mode of the oil pumping well group based on photovoltaic power generation. The control system of the oil pumping well group is designed by utilizing the photovoltaic power generation law and the oil well fluid supply law. Through multi-well coordination, the photovoltaic power generation is matched with the electricity consumption of the oil pumping well group, the abandonment rate is reduced, and the problem that the current oil pumping photovoltaic power generation system needs energy storage or the power grid to cooperate with the peak regulation is solved. The ineffective working time of the oil pump is reduced, the application cost of the photovoltaic power supply system on the oil pumping well group is effectively reduced, and low-cost carbon reduction oil production is achieved.

[0034] The integrated control system for pumping unit inverter inter-pumping described in the present invention can dilute the investment cost of a single well by centralized control of the pumping unit well group, use group control technology to distribute photovoltaic power on demand and reduce the rate of abandoned light, and use inter-pumping well follow-up control technology to reduce the ineffective working time of the pumping unit and reduce power consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a flow chart of the control method of the present invention.

[0036] Figure 2 It is a schematic diagram of the control system structure of the present invention. DETAILED DESCRIPTION

[0037] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments: This embodiment is implemented on the premise of the technical scheme of the present invention, and an implementation method and an operation process are given, but the protection scope of the present invention is not limited to the following embodiments.

[0038] In the description of the present invention, unless otherwise specified, "plurality" means two or more than two. In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0039] Example 1

[0040] Referring to 1, the present invention provides an optimization design method for the intermittent pumping system coupled with photovoltaic power generation and electricity consumption of a group of pumping wells. It adopts a combination of remote monitoring and front-end control to ensure that the photovoltaic power generation state and the oil well start-stop system can be reasonably matched under the premise that the oil well fluid production does not decrease. The pumping units in the same photovoltaic system timing unit establish a staggered well opening and intermittent pumping plan based on the oil well fluid supply situation and photovoltaic power generation power. That is, when the photovoltaic power generation power is high, multiple wells are started for pumping, and when the photovoltaic power generation power is low, multiple wells are stopped for pumping, and the wells are not opened when there is no light at night. The pumping well switch system is kept consistent with the light conditions as much as possible, and the oil well start-stop system is matched with the photovoltaic power generation power to reduce the abandonment rate as much as possible.

[0041] The principle of this method is to establish a single-well inter-pumping system within the well group based on the liquid discharge rules of each well when it is opened and the liquid level recovery rules after the well is closed. At the same time, based on the real-time monitoring data of the photovoltaic power generation status, the start-stop strategy of the oil well at a certain stage is determined to achieve follow-up control of photovoltaic power generation and the start-stop of the oil well.

[0042] The servo control method for photovoltaic power generation and oil well start-up and shutdown is as follows: according to the collected real-time photovoltaic power generation and the calculated single-well inter-pumping system in the well group, the opening time of each single well in the well group is matched; when the photovoltaic power generation power is high, more wells are pumped; when the photovoltaic power generation power is low, fewer wells are pumped, so that the opening time of each well is matched with the photovoltaic power generation power while meeting the opening time of a single well.

[0043] Its technical route is based on the formation fluid supply capacity, oil well lifting capacity, and photovoltaic power generation capacity, with the constraints of maintaining production and ensuring motor starting current, and the goal of minimizing the abandoned light rate. A solution model for the start-stop system of the pumping well group is established, and the start-stop time of each pumping unit in the well group is optimized through the peak-shaving operation control system of the pumping well group based on photovoltaic power generation.

[0044] The pumping unit inverter timing integrated control system adopts a combination of remote monitoring and front-end control to ensure that the pumping units in the same photovoltaic system timing control unit establish a peak-shifting well-to-well pumping plan based on the oil well fluid supply situation and photovoltaic power generation power, without reducing the oil well fluid production. The specific implementation steps are as follows:

[0045] Step 1: First, select a group of wells with relatively poor liquid supply capacity and low oil pump efficiency, study the liquid discharge law of each well in the well group when it is opened and the liquid level recovery law after the well is closed, and form a single well inter-pumping system in the well group. In this embodiment, relatively poor liquid supply capacity means that the daily liquid production is less than 5t / d; low oil pump efficiency means that the oil pump efficiency is less than 30%.

[0046] The method for establishing the inter-well pumping system in a well group is as follows: first, the dynamometer diagram collected by the pumping unit suspension point dynamometer is used to calculate the filling degree of the downhole oil pump (the dynamometer diagram collection frequency is 10min / frame), and then the inter-well pumping system is formulated according to the changing law of the filling degree of the oil pump. When the oil pump is running continuously, the filling degree of the oil pump is calculated once every 10 minutes using the collected dynamometer diagram. If the initial calculation of the filling degree of the oil pump is lower than 50%, the unit is shut down to wait for the oil well to restore the liquid level. After the initial calculation of the filling degree of the oil pump is higher than 50%, the filling degree of the oil pump is calculated continuously every 10 minutes until the calculated filling degree of the oil pump is lower than 40%. The continuous operation time of the pumping is recorded as the opening time of the inter-well pumping system. The filling degree of the oil pump is calculated as the ratio of the volume of liquid entering the oil pump during the upstroke to the volume of liquid released by the plunger. The calculation formula is:

[0047]

[0048] Where η 泵 is the filling degree of the oil pump, V 排 V is the volume of liquid discharged from the oil pump barrel. 柱 Make room for the pump barrel plunger, S 柱塞is the plunger area, L1 is the effective liquid inlet stroke, and L2 is the effective stroke.

[0049] Step 2: According to the light resource conditions of the well site, simulate the daily power curve of different photovoltaic installed power conditions, and select the photovoltaic installed capacity that is suitable for the power consumption of the timing control of the oil pumping well group.

[0050] The calculation method of photovoltaic installed capacity is as follows:

[0051]

[0052] P—PV array installed capacity, in kilowatt-peak (kWp);

[0053] Pv—capacity ratio of photovoltaic system, decimal;

[0054] P Ri —Rated power of the motor used for the i-th well in the pumping well group, in kilowatts (kW);

[0055] R Li — Load rate of the motor used for the i-th well in the pumping well group, decimal;

[0056] α i —Daily opening time of the i-th well in the pumping well group, in hours (h);

[0057] T U — Annual equivalent utilization hours of photovoltaic power generation system, in hours (h);

[0058] η—The overall system efficiency of the photovoltaic power station, decimal.

[0059] Step 3: Establish a system for switching on and off pumping wells that matches the real-time photovoltaic power generation, and form a zero-carbon oil production plan that complements the temporal and spatial variation laws with the oil well fluid supply laws.

[0060] The operation and scheduling optimization model of the pumping well group is based on the formation fluid supply capacity, oil well lifting capacity, and photovoltaic power generation capacity, with the constraints of no production reduction and ensuring the starting current of the motor, and the goal of minimizing the abandoned light rate. Under the premise of ensuring the oil well production, the photovoltaic power generation state and the oil well start-stop system can be reasonably matched, that is, when the photovoltaic power generation power is high, more wells are started to pump, and when the photovoltaic power generation power is low, more wells are stopped to pump, so as to match the oil well start-stop system with the photovoltaic power generation power.

[0061] Step 4: The formed pumping well group switching system is implanted into the pumping unit inverter timing integrated control system, and the timing control plan is executed through the control system.

[0062] Example 2

[0063] Reference Figure 2The present invention provides a schematic structural diagram of a peak-shifting operation control system for a group of pumping wells based on photovoltaic power generation. The system is composed of a photovoltaic component and an integrated control system for a pumping unit inverter sequence. A number of pumping wells are used as a photovoltaic control unit. The photovoltaic component strings are boosted and then connected to an off-grid inverter to convert into low-voltage alternating current. The power is then connected to an inter-pumping control module of the pumping unit through an MPPT controller, an inverter module, and an output filter module to achieve time-sharing peak-shifting and variable-frequency starting of the group of pumping wells. According to the results of the optimization calculation of the operation scheduling model of the group of pumping wells, the start and stop instructions of each well in the system are issued through the centralized inter-pumping control module.

[0064] The pumping unit inverter timing integrated control system of the present invention includes: MPPT controller, PLC controller, inverter module, output filter module, intermittent pumping control module, pumping unit electrical parameter monitoring module, 4G communication module, and remote monitoring terminal. The system uses PLC as a control unit, which can realize the automatic timing control function of the pumping unit well group based on photovoltaic power generation.

[0065] The input end of the MPPT controller is connected to the photovoltaic module, the output end is connected to the input end of the inverter module, the output end of the inverter module is connected to the input end of the output filter module, the output end of the output filter module is connected to the input end of the inter-pumping control module, the inter-pumping control module is connected to the pumping unit electrical parameter monitoring module and the input end of all pumping units, and the output end of the pumping unit electrical parameter monitoring module is connected to the input end of the PLC controller. The PLC controller communicates with the 4G communication module in a two-way manner, the output end of the PLC controller is connected to the input end of the inter-pumping control module, and the 4G communication module communicates with the remote monitoring terminal.

[0066] The oil pumping units include first to nth oil pumping units.

[0067] The MPPT controller is used to maximize the output power of the photovoltaic module; the inverter module is used to convert the DC power output by the photovoltaic module into AC power; the output filter module is used to filter the AC power;

[0068] The pumping unit electrical parameter monitoring module is used to monitor the electrical parameters of the pumping unit, and the electrical parameters include: the pumping unit motor input power, the pumping unit motor power factor, the pumping unit motor operating voltage and the pumping unit motor operating current;

[0069] The PLC controller is used to establish a pumping well group switching system that matches the real-time photovoltaic power generation according to the electrical parameters of the pumping units; the intermittent pumping control module is used to control the pumping units according to the pumping well group switching system.

[0070] Example 3

[0071] A computer device provided by the present invention comprises an electrically connected memory and a processor, wherein the memory stores a computer program that can be run on the processor, and when the processor executes the computer program, the control method described in Example 1 is implemented.

[0072] The computer program may be divided into one or more modules / units, and the one or more modules / units are stored in the memory and executed by the processor to accomplish the present invention.

[0073] The processor can be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc.

[0074] The memory may be used to store the computer programs and / or modules, and the processor implements various functions of the control device / terminal equipment by running or executing the computer programs and / or modules stored in the memory and calling the data stored in the memory.

[0075] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0076] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a non-volatile computer-readable storage medium that is executable by a processor. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods described in each embodiment of the present invention. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0077] Example 4

[0078] A computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the control method are implemented. Specifically, the computer-readable storage medium includes, but is not limited to, volatile memory and / or non-volatile memory. The volatile memory may include random access memory (RAM) and / or cache memory, etc. The non-volatile memory may include read-only memory (ROM), hard disk, flash memory, optical disk, magnetic disk, etc.

[0079] The above contents are only for explaining the technical idea of ​​the present invention and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the present invention shall fall within the protection scope of the claims of the present invention.

Claims

1. A method for coupling control of photovoltaic power generation and peak-shifting operation of a group of pumping wells, characterized in that: The following steps are involved: Step 1: Establish a single well inter-pumping system within the pumping well group based on the liquid discharge law of each well when it is opened and the liquid level recovery law after the well is closed; Step 2: According to the light resource conditions of the well site, simulate the daily power curve of different photovoltaic installed power conditions, and select the photovoltaic installed capacity that is suitable for the power consumption of the timing control of the oil pumping well group; Step 3: Establish a system for switching on and off pumping wells that matches the real-time photovoltaic power generation, and form a zero-carbon oil production plan that complements the temporal and spatial variation laws with the oil well fluid supply laws.

2. A photovoltaic power generation and oil pumping well group staggered operation coupling control method according to claim 1, characterized in that: In the step 1, the oil pumping well group is a oil pumping well group with relatively poor fluid supply capacity and low oil pump efficiency.

3. The photovoltaic power generation and pumping well group peak shifting operation coupling control method according to claim 1 is characterized in that: The step 1 comprises the following steps: S1.

1. Calculate the fullness of the downhole oil pump; S21. Formulate a single well inter-pumping system based on the changing law of the filling degree of the oil pump; When the oil pump is running continuously, the fullness of the oil pump is calculated once at an interval set time using the collected indicator diagram. If the initial calculated fullness of the oil pump is lower than the first set value, the unit is shut down and waits for the oil well to recover the liquid level. After the initial calculated fullness of the oil pump is higher than the first set value, the fullness of the oil pump is calculated continuously at set intervals until the calculated fullness of the oil pump is lower than the second set value. The continuous operation time of the oil pumping is recorded as the well opening time of the intermittent pumping system, and the second set value is less than the first set value.

4. A photovoltaic power generation and oil pumping well group staggered operation coupling control method according to claim 3, characterized in that: In the step S1.1, the fullness of the downhole oil pump is calculated using the dynamometer diagram.

5. The photovoltaic power generation and pumping well group peak shifting operation coupling control method according to claim 3 is characterized in that: The degree of filling of the oil well pump is calculated as the ratio η of the volume of liquid entering the oil well pump during the upstroke to the volume of liquid released by the plunger. The calculation formula is: Where η 泵 is the filling degree of the oil pump, L1 is the effective liquid inlet stroke, and L2 is the effective stroke.

6. The photovoltaic power generation and pumping well group peak shifting operation coupling control method according to claim 1 is characterized in that: In step 2, the photovoltaic installed capacity is calculated by the following formula: Where P is the installed capacity of photovoltaic array; Pv is the capacity ratio of photovoltaic system; Ri —Rated power of the motor used for the i-th well in the pumping well group; R Li —Load rate of the motor used for the i-th well in the pumping well group; α i —Daily opening time of the i-th well in the pumping well group; T U —Annual equivalent utilization hours of photovoltaic power generation system; η—comprehensive system efficiency of photovoltaic power station.

7. The photovoltaic power generation and pumping well group peak shifting operation coupling control method according to claim 1 is characterized in that: The step 3 comprises the following steps: Based on the formation fluid supply capacity, oil well lifting capacity and photovoltaic power generation capacity, with the constraints of maintaining production and ensuring the starting current of the motor, and the goal of minimizing the abandonment rate of light, under the premise of ensuring the production of the oil wells, more wells will be started when the photovoltaic power generation power is high, and more wells will be stopped when the photovoltaic power generation power is low, so as to match the oil well start-stop system with the photovoltaic power generation power.

8. A photovoltaic power generation and oil pumping well group peak shifting operation coupling control system, characterized in that: include: MPPT controller, used to maximize the output power of photovoltaic modules; Inverter module, used to convert the direct current output by the photovoltaic module into alternating current; Output filter module, used for filtering AC power; The electrical parameter monitoring module of the oil pump is used to monitor the electrical parameters of the oil pump; The PLC controller is used to establish a well opening and closing system for the well group of the pumping units that matches the real-time photovoltaic power generation according to the electrical parameters of the pumping units; The intermittent pumping control module is used to control the pumping units according to the switching well system of the pumping well group.

9. A computer device, characterized in that: The method comprises an electrically connected memory and a processor, wherein the memory stores a computer program executable on the processor, and when the processor executes the computer program, the steps of the method described in any one of claims 1 to 6 are implemented.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

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