Pumping unit micro-grid micro-storage green electricity intelligent group control system

Abstract

The invention relates to the technical field of oil production engineering, in particular to a pumping unit micro-grid micro-storage green power intelligent group control system which is characterized in that a mains supply power grid and a green power generation system are connected with a direct current bus through execution units, and the direct current bus is connected with a plurality of pumping units through inversion units; the oil well centralized control unit is connected with the execution unit and the inversion unit. The oil well centralized control unit is used for obtaining and adjusting the real-time power generation electric energy of the green power generation system through the execution unit, controlling the electric energy of the commercial power grid and / or the green power generation system to be transmitted to the DC bus, and obtaining the real-time operation state of the oil pumping unit through the inversion unit. And the real-time power generation electric energy of the green power generation system and the real-time power utilization electric energy during the operation of the pumping unit are adjusted according to the real-time operation state to achieve balance. The problems that an existing power generation device of each oil pumping unit can only supply power to one oil pumping unit, the power supply capacity is small, and a motor of the oil pumping unit is prone to being burnt out due to the fact that power sources need to be switched frequently during power supply are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of oil production engineering, and in particular to an intelligent group control system for microgrid, micro-storage and green electricity of oil pumping units. Background Art

[0002] The existing pumping unit generator is that when the pumping rod of the pumping unit rises, the working motor draws energy from the external power grid to work on the pumping unit. When the pumping rod of the pumping unit descends, the controller switches the power output, the pumping unit works on the generator motor, and the generator motor stores the energy in the battery. Its defects are that under normal conditions, the pumping unit has only one power source and there is no way to connect two motors at the same time; repeatedly cutting off the power supply of the working motor will cause the motor to burn out and fail; and affected by factors such as well conditions, without power drive, it is impossible to ensure that the pumping rod descends normally and generates electricity and stores energy; in addition, because the upper and lower dead points of the pumping unit cannot be accurately detected, the switching of the two motors cannot be completed accurately. Summary of the invention

[0003] The present invention proposes an intelligent group control system for microgrid and micro-storage green electricity of oil pumps to solve the problem that each existing oil pumping unit power generation device can only supply power to one oil pumping unit, has a small power supply capacity, and needs to frequently switch power sources when supplying power, which causes the oil pumping unit motor to be easily burned out.

[0004] According to one aspect of the present invention, there is provided a pumping unit microgrid microstorage green electricity intelligent group control system, comprising: a green electricity generation system, a city power grid, an inverter unit, a DC bus, an oil well centralized control unit and an execution unit; The mains power grid and the green electricity generation system are connected to the DC bus through the execution unit, and the DC bus is respectively connected to a plurality of pumping units through the inverter unit; The oil well centralized control unit is respectively connected to the execution unit and the inverter unit; The oil well centralized control unit is used to obtain and adjust the real-time power generation energy of the green electricity generation system through the execution unit, and to control the transmission of power from the city power grid and / or the green electricity generation system to the DC bus; The oil well centralized control unit is used to obtain the real-time operating status of the oil pump through the inverter unit, and adjust the real-time power generation energy of the green power generation system and the real-time power consumption of the oil pump during operation to achieve a balance according to the real-time operating status.

[0005] Preferably, the green electricity generation system comprises: an oil pump feedback power generation device, a wind power generation device and a photovoltaic power generation device; The oil pump feedback power generation device, wind power generation device and photovoltaic power generation device are respectively connected to the execution unit. The oil pump feedback power generation device is used to generate electricity by utilizing the downstroke of the oil pump, the wind power generation device is used to generate electricity by converting wind energy into electrical energy, and the photovoltaic power generation device is used to generate electricity by converting solar energy into electrical energy.

[0006] Preferably, the step of adjusting the real-time power generation energy of the green electricity generation system according to the operating state to achieve a balance with the real-time power consumption energy of the oil pump during operation includes: The operating state includes: upstroke and downstroke; The oil well centralized control unit collects the operating status of each of the pumping units, and determines whether a first predetermined number of pumping units among all the pumping units are in an upstroke, and a second predetermined number of pumping units are in a downstroke. If not, the oil well centralized control unit adjusts the operating status of the pumping units through the inverter unit, so that the first predetermined number of pumping units are in an upstroke, and the second predetermined number of pumping units are in a downstroke.

[0007] Preferably, it also includes: an energy storage charging and discharging unit; The energy storage charging and discharging unit is connected to the DC bus and the oil well centralized control unit respectively, and the energy storage charging and discharging unit is used to store or release the electric energy generated by the green electricity generation system.

[0008] Preferably, the oil well centralized control unit is further used to obtain the real-time voltage value on the DC bus, and determine whether the real-time voltage value is greater than the first predetermined voltage value. If so, the oil well centralized control unit controls the energy storage charging and discharging unit to start, and stores part of the current on the DC bus that exceeds the first predetermined voltage value; The oil well centralized control unit is also used to control the energy storage charging and discharging unit to start when it determines that the real-time voltage value is less than a second predetermined voltage value, and transmit the current stored in it into the DC bus, so that the real-time voltage value on the DC bus is equal to the second predetermined voltage value.

[0009] Preferably, the execution unit comprises: a voltage detection module and an AC-DC converter; The voltage detection module is connected to the green electricity generation system and the oil well centralized control unit respectively, and the voltage detection module is used to detect the real-time power generation energy of the green electricity generation system and transmit it to the oil well centralized control unit; The AC / DC converter is connected between the green electricity generation system and the DC bus, and the AC / DC converter is connected to the oil well centralized control unit. The oil well centralized control unit is also used to control the connection or disconnection of the line between the green electricity generation system and the DC bus through the AC / DC converter.

[0010] Preferably, the inverter unit comprises: a frequency converter and a position detection module; The motor of each oil pump is connected to the DC bus through the corresponding frequency converter, and the frequency converter is used to convert the DC power transmitted by the DC bus into AC power and then transmit it to the corresponding oil pump motor for power supply; The oil well centralized control unit is connected to the frequency converter and the position detection module respectively, and the oil well centralized control unit is also used to detect the real-time operating status of the oil pumping unit through the position detection module.

[0011] Preferably, the oil well centralized control unit detects the real-time voltage value of the DC bus and determines whether the real-time voltage value of the DC bus is lower than a second predetermined voltage value. If so, the oil well centralized control unit controls the connection of the line between the mains power grid and the DC bus through the execution unit. If not, the oil well centralized control unit controls the disconnection of the line between the mains power grid and the DC bus through the execution unit.

[0012] The present invention has at least the following beneficial effects: The present invention proposes a microgrid and micro-storage green electricity intelligent group control system for oil pumps. The system forms a microgrid group control system by connecting a green electricity generation system and multiple oil pumps through a DC bus, and uses an oil well centralized control unit to regulate the power supply and power consumption, thereby realizing group control intelligent power supply, avoiding adverse effects of frequent switching of oil pump motors on their normal operation, and improving the power supply stability of the oil pumps. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The accompanying drawings herein are incorporated into and constitute a part of the specification. These drawings illustrate embodiments consistent with the present invention and, together with the specification, are used to explain the technical solutions of the present invention.

[0014] Figure 1 A schematic diagram of equipment connection of an intelligent group control system for microgrid, micro-storage and green electricity of an oil pumping unit according to an embodiment of the present invention is shown. Implementation

[0015] Various exemplary embodiments, features and aspects of the present invention will be described in detail below with reference to the accompanying drawings. The same reference numerals in the accompanying drawings represent elements with the same or similar functions. Although various aspects of the embodiments are shown in the accompanying drawings, the drawings are not necessarily drawn to scale unless otherwise specified.

[0016] The word “exemplary” is used exclusively herein to mean “serving as an example, example, or illustration.” Any embodiment described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments.

[0017] The term "and / or" herein is only a description of the association relationship of the associated objects, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the term "at least one" herein represents any combination of at least two of any one or more of a plurality of. For example, including at least one of A, B, and C can represent including any one or more elements selected from the set consisting of A, B, and C.

[0018] In addition, in order to better illustrate the present invention, numerous specific details are provided in the following specific embodiments. It should be understood by those skilled in the art that the present invention can be implemented without certain specific details. In some examples, methods, means, components and circuits well known to those skilled in the art are not described in detail in order to highlight the subject matter of the present invention.

[0019] Figure 1 The following is a schematic diagram showing the equipment connection of an intelligent group control system for a pumping unit microgrid microstorage green electricity according to an embodiment of the present invention. Figure 1 As shown, a pumping unit microgrid micro-storage green electricity intelligent group control system includes: a green electricity generation system, a mains power grid, an inverter unit, a DC bus, an oil well centralized control unit and an execution unit; the mains power grid and the green electricity generation system are connected to the DC bus through the execution unit, and the DC bus is respectively connected to a number of pumping units through the inverter unit; the oil well centralized control unit is respectively connected to the execution unit and the inverter unit; the oil well centralized control unit is used to obtain and adjust the real-time power generation energy of the green electricity generation system through the execution unit, and to control the transmission of the power of the mains power grid and / or the green electricity generation system to the DC bus; the oil well centralized control unit is used to obtain the real-time operating status of the pumping unit through the inverter unit, and adjust the real-time power generation energy of the green electricity generation system and the real-time power consumption of the pumping unit during operation to achieve a balance according to the real-time operating status.

[0020] In an embodiment of the present invention, when power is supplied, the AC and DC power generated by the green power generation system are converted into DC power by the execution unit and then transmitted to the DC bus, and then transmitted to the inverter unit through the DC bus. The inverter unit converts the DC power into AC power, and adjusts the voltage to the voltage value required for the operation of the corresponding pumping unit (tower machine) motor, and then transmits it to the pumping unit motor to power it.

[0021] During the operation of the oil pumps, the oil well control unit can obtain the operating status of each connected oil pump through the inverter unit, thereby obtaining the total power consumption of all the oil pumps at each moment, that is, the real-time total power consumption, and the oil well control unit can obtain the real-time total power generation of the green electricity generation system through the execution unit, that is, the real-time power generation amount.

[0022] The oil well centralized control unit compares the real-time total power generation with the real-time total power consumption. If the real-time total power generation exceeds the preset value of the real-time total power consumption, the oil well centralized control unit adjusts the real-time total power generation of the green power generation system through the execution unit to reduce the real-time total power generation, thereby achieving a balance between power generation and power consumption and preventing the DC bus voltage from being too high and damaging the line.

[0023] In the present invention, the green electricity generation system includes: an oil pump feedback power generation device, a wind power generation device and a photovoltaic power generation device; the oil pump feedback power generation device, the wind power generation device and the photovoltaic power generation device are respectively connected to the execution unit, the oil pump feedback power generation device is used to generate electricity by utilizing the downstroke of the oil pump, the wind power generation device is used to generate electricity by converting wind energy into electrical energy, and the photovoltaic power generation device is used to generate electricity by converting solar energy into electrical energy.

[0024] In the embodiment of the present invention, each oil pump is respectively connected to a corresponding oil pump feedback power generation device, which can generate electricity through the downstroke of the oil pump; the wind power generation device generates electricity by utilizing the natural wind energy in the site space occupied by the oil pump, by converting the wind energy into mechanical energy, and then converting the mechanical energy into electrical energy; the photovoltaic power generation device generates electricity by utilizing the site space occupied by the oil pump, by irradiating the PN junction of the photovoltaic module with sunlight, and by utilizing the photovoltaic effect to generate voltage in the PN junction.

[0025] When in use, the oil well centralized control unit controls the electric energy generated by the start-up of the pumping unit feedback power generation device, wind power generation device and photovoltaic power generation device through the execution unit. The electric energy is then transmitted to the DC bus through the execution unit. After being collected on the DC bus, it is transmitted to each pumping unit that needs power supply through the inverter unit, thereby ensuring the stability of the power supply.

[0026] During operation, when the oil well control unit detects the total amount of electric energy generated when the pumping unit feedback power generation device, wind power generation device and photovoltaic power generation device are running simultaneously, that is, the real-time total power generation exceeds the predetermined value of the real-time total power consumption of all pumping units, the oil well control unit controls all or part of the equipment in the pumping unit feedback power generation device, wind power generation device and photovoltaic power generation device through the execution unit to shut down and stop generating electricity, thereby ensuring that the power supply voltage will not be too high.

[0027] In the present invention, the real-time power generation energy of the green electricity generation system is adjusted according to the operating state to achieve a balance with the real-time power consumption of the oil pumping unit during operation, including: the operating state includes: upstroke and downstroke; the oil well centralized control unit collects the operating state of each of the oil pumping units through the inverter unit, and determines whether a first predetermined number of oil pumping units among all the oil pumping units are in the upstroke and a second predetermined number of oil pumping units are in the downstroke; if not, the oil well centralized control unit adjusts the operating state of the oil pumping units through the inverter unit, so that the first predetermined number of oil pumping units are in the upstroke and the second predetermined number of oil pumping units are in the downstroke.

[0028] In the embodiment of the present invention, the values ​​of the first predetermined number and the second predetermined number can be completely the same or approximately the same, that is, if the total number of pumping units is 10, the first predetermined number and the second predetermined number are both 5. The oil well centralized control unit can collect the real-time operating status of each pumping unit motor through the inverter unit, and adjust the pumping strokes through the inverter unit according to the real-time operating status to ensure that the number of pumping units in the downstroke at the same time is approximately the same as the number of pumping units in the upstroke, so as to achieve staggered operation, thereby ensuring that the power generation of the pumping unit feedback power generation device connected to the pumping unit and the power consumption of the pumping unit are basically balanced, avoiding a large number of pumping units from generating power in the downstroke feedback and consuming power in the upstroke at the same time, and ensuring the stability of the power supply system.

[0029] The present invention also includes: an energy storage charging and discharging unit; the energy storage charging and discharging unit is respectively connected to the DC bus and the oil well centralized control unit, and the energy storage charging and discharging unit is used to store or release the electric energy generated by the green electricity generation system.

[0030] In the present invention, the oil well centralized control unit is also used to obtain the real-time voltage value on the DC bus and determine whether the real-time voltage value is greater than the first predetermined voltage value. If so, the oil well centralized control unit controls the energy storage charging and discharging unit to start and store part of the current on the DC bus that exceeds the first predetermined voltage value. The oil well centralized control unit is also used to determine that when the real-time voltage value is less than a second predetermined voltage value, control the energy storage charging and discharging unit to start and transmit the current stored in it into the DC bus, so that the real-time voltage value on the DC bus is greater than or equal to the second predetermined voltage value.

[0031] In an embodiment of the present invention, the energy storage charging and discharging unit includes: an energy storage battery. The energy storage battery is connected to the charging and discharging management module, and the charging and discharging management module is connected to the oil well centralized control unit. In the initial state, the oil well centralized control unit controls the line between the energy storage charging and discharging unit and the DC bus to be disconnected. The charging and discharging management module is used to detect the real-time voltage value on the DC bus and transmit it to the oil well centralized control unit. The oil well centralized control unit determines whether the real-time voltage value is greater than the first predetermined voltage value, wherein the first predetermined voltage value is 600V; if yes, the oil well centralized control unit controls the DC bus and the energy storage charging and discharging unit, that is, the line between the energy storage battery is connected, part of the current on the DC bus enters the energy storage battery, and the energy storage battery stores electrical energy. In this process, if the oil well centralized control unit determines that the real-time voltage value on the DC bus is equal to 600V, it controls the line between the energy storage battery and the DC bus to be disconnected, and stops energy storage, thereby preventing the DC bus voltage from being too low to meet the operation of the pumping unit.

[0032] During the operation of the oil pump, the oil well control unit determines whether the real-time voltage value on the DC bus is less than a second predetermined voltage value, where the second predetermined voltage value is 600V; if so, the oil well control unit controls the connection between the energy storage battery and the DC bus, and uses the energy storage battery to supplement the power supply for the oil pump motor.

[0033] In an embodiment of the present invention, the oil well centralized control unit detects the real-time voltage value on the DC bus and determines whether the real-time voltage value is greater than a first predetermined voltage value. If so, the oil well centralized control unit detects whether all the energy storage batteries in the energy storage charging and discharging unit are in a fully charged state. If so, the oil well centralized control unit controls the pump feedback power generation device, the wind power generation device and the photovoltaic power generation device through the execution unit to shut down all or part of the devices and stop generating electricity, thereby ensuring that the real-time voltage value on the DC bus is not greater than the first predetermined voltage value.

[0034] If the green power generation system generates too much electricity, the excess energy can be stored in the energy storage battery. However, if the energy storage battery is already full, it is necessary to reduce the power generation by adjusting the number of power generation equipment. Therefore, when the voltage on the DC bus is too high, it is necessary to first determine the status of the energy storage battery, and then determine whether to store energy through the battery or shut down the power generation equipment to adjust the DC bus voltage.

[0035] In an embodiment of the present invention, during the operation of the oil pump, the oil well centralized control unit determines whether the real-time voltage value on the DC bus is less than the second predetermined voltage value. If so, the oil well centralized control unit detects whether all the equipment in the oil pump feedback power generation device, the wind power generation device and the photovoltaic power generation device are in operation. If so, the oil well centralized control unit controls the line connection between the energy storage battery and the DC bus to supplement the power supply for the oil pump motor. If not, the oil well centralized control unit controls the non-operating devices in the oil pump feedback power generation device, the wind power generation device and the photovoltaic power generation device to start operation, and after controlling all the power generation devices to start operation, determines whether the real-time voltage value on the DC bus is greater than or equal to the second predetermined voltage value. If not, controls the line connection between the energy storage battery and the DC bus to supplement the power supply for the oil pump motor.

[0036] If the voltage on the DC bus is too low and cannot meet the normal power supply requirements, it is necessary to first determine whether all the power generation devices in the green power generation system are in operation. If there are devices that are not in operation, they can be started to supplement power generation. If all power generation equipment has been started, but the voltage on the DC bus still cannot meet the requirements, it can be supplemented by energy storage batteries.

[0037] The electricity generated when the pump is running in the downstroke and the electricity generated by the wind power generation device and photovoltaic power generation device installed in the working area are stored in the energy storage battery, adjusted to the working voltage by a transformer, and then supplied to other pumps for upstroke operation through the bus. This not only utilizes the reverse electricity generated by the motor and reduces interference to the power grid, but also improves the operating efficiency of the motor and achieves energy saving.

[0038] In the present invention, the execution unit includes: a voltage detection module and an AC-DC converter; the voltage detection module is connected to the green electricity generation system and the oil well centralized control unit respectively, and the voltage detection module is used to detect the real-time power generation energy of the green electricity generation system and transmit it to the oil well centralized control unit; the AC-DC converter is connected between the green electricity generation system and the DC bus, and the AC-DC converter is connected to the oil well centralized control unit. The oil well centralized control unit is also used to control the connection or disconnection of the line between the green electricity generation system and the DC bus through the AC-DC converter.

[0039] In an embodiment of the present invention, the mains power grid, the oil pump feedback power generation device, the wind power generation device and the photovoltaic power generation device are respectively connected to the DC bus through corresponding AC-DC converters (AC-DC converters). The AC-DC converter is used to convert the AC power transmitted by the mains power grid and generated by the oil pump feedback power generation device and the wind power generation device into DC power and then transmit it to the DC bus; the electric energy generated by the photovoltaic power generation device is DC power and does not need to be converted.

[0040] The voltage detection module is respectively connected to the AC / DC converters corresponding to each oil pump feedback power generation device, wind power generation device, and photovoltaic power generation device; the voltage detection module detects the real-time voltage value passing through the AC / DC converter and transmits it to the oil well centralized control unit. The oil well centralized control unit can calculate the power generation of each power generation device and the real-time total power generation of all power generation devices in operation at this time based on the real-time voltage value, so as to compare the real-time total power generation with the real-time total power consumption of all oil pumps when they are running. If the real-time total power generation exceeds the preset value of the real-time total power consumption, the oil well centralized control unit controls the shutdown of the preset number of power generation devices in the oil pump feedback power generation device, wind power generation device, and photovoltaic power generation device through the AC / DC converter, thereby reducing the total power generation and balancing the total power supply and total power consumption.

[0041] In the present invention, the inverter unit includes: a frequency converter and a position detection module; the motor of each of the oil pumps is connected to the DC bus through the corresponding frequency converter, and the frequency converter is used to convert the DC power transmitted by the DC bus into AC power and then transmit it to the corresponding oil pump motor for power supply; the oil well centralized control unit is respectively connected to the frequency converter and the position detection module, and the oil well centralized control unit is also used to detect the real-time operating status of the oil pump through the position detection module.

[0042] In an embodiment of the present invention, the position detection module includes: a proximity switch or a rotary transformer, which is connected to the pumping unit motor and the oil well centralized control unit respectively. After the proximity switch and the rotary transformer are started, they can detect the real-time rotation position and angle of the pumping unit motor, and transmit the real-time rotation position and angle value to the oil well centralized control unit; the oil well centralized control unit can judge whether the current operating state of the pumping unit is in the upstroke or downstroke according to the rotation position and angle, that is, the real-time operating state.

[0043] The oil well centralized control unit determines whether half of all the pumping units are in the upstroke and half of the pumping units are in the downstroke. If not, the oil well centralized control unit adjusts the pumping strokes through the frequency converter so that the number of all the pumping units in the upstroke and downstroke is the same, so that power generation and power consumption are balanced.

[0044] In the present invention, the oil well centralized control unit detects the real-time voltage value of the DC bus and determines whether the real-time voltage value of the DC bus is lower than a third predetermined voltage value. If so, the oil well centralized control unit controls the connection of the line between the mains power grid and the DC bus through the execution unit. If not, the oil well centralized control unit controls the disconnection of the line between the mains power grid and the DC bus through the execution unit.

[0045] In an embodiment of the present invention, the oil well centralized control unit detects the real-time voltage value of the DC bus and determines whether the real-time voltage value of the DC bus is lower than a third predetermined voltage value. If yes, it determines whether all power generation devices in the green power generation system are in operation and whether the line between the energy storage battery and the DC bus is connected. If yes, the oil well centralized control unit controls the line connection between the mains power grid and the DC bus through the execution unit. If not, the oil well centralized control unit controls the non-operating power generation device to start operation and / or controls the line connection between the DC bus and the energy storage battery. After controlling the non-operating power generation device to start operation and / or the line connection between the DC bus and the energy storage battery, it determines whether the real-time voltage value on the DC bus is still lower than the third predetermined voltage value. If yes, the oil well centralized control unit controls the line connection between the mains power grid and the DC bus through the execution unit, and supplements the power supply through the external power grid.

[0046] When the voltage on the DC bus is too low to meet the power supply requirements, it is first detected whether the power generation devices have started to generate electricity and whether they are connected to the energy storage battery for supplementary power supply. If both are yes, it means that the green power generation system and the energy storage charging and discharging unit cannot meet the power supply demand at this time, so it is supplemented by connecting to the external power grid.

[0047] It can be understood that the above-mentioned various embodiments mentioned in the present invention can be combined with each other to form a combined embodiment without violating the principle logic. Due to space limitations, the present invention will not go into details.

[0048] The present invention uses a wind power generation device to convert the wind energy in the space occupied by the oil pump from mechanical energy to electrical energy through a wind turbine to generate electricity; uses a photovoltaic power generation device to utilize the photovoltaic space occupied by the oil pump to generate a photovoltaic effect when sunlight irradiates the PN junction of the photovoltaic module, thereby generating voltage for power generation; uses a feedback power generation device from the oil pump to utilize the power of the downstroke of the oil pump to generate electricity, thereby providing sufficient electricity during the operation of the oil pump; and, by providing an energy storage charging unit, excess electricity is stored and supplementary power is provided when necessary; at the same time, when both the power generation device and the energy storage charging and discharging unit cannot meet the power supply requirements, supplementary power is provided by connecting to the external network to ensure stable operation of the oil pump motor.

[0049] The present invention also connects various power generation devices, energy storage charging and discharging units and various pumping motors in parallel to form a microgrid by setting a DC bus, forming a microgrid micro-storage power supply system, and realizing intelligent group control through the oil well centralized control unit, inverter unit and execution unit. Among them, the inverter unit adopts an advanced closed-loop vector algorithm to accurately control the pumping motor, and the inverter unit has a built-in pumping motor-specific control macro program, which reduces the difficulty of debugging and simplifies the on-site operation process, and independently controls the speed, torque and magnetic field of the pumping motor; controls the motor current through the motor current loop, so that the motor current matches the given current instruction, and realizes precise control of the motor operation state; controls the motor speed through the speed loop, and realizes the speed (stroke) control of the motor by adjusting the motor speed; uses a rotary transformer or a proximity switch to read the motor position, and realizes the position control of the motor by adjusting the rotation position of the motor, thereby realizing the staggered operation of the pumping unit. The oil well centralized control unit collects the working status of each unit in the system in real time, automatically and reasonably adjusts the system operation mode and parameters, and analyzes the oil well load situation based on the collected inverter unit data; through the logic control module in the oil well centralized control unit, it collects the power generation power and current and other parameter conditions of each power generation device in the system in real time, and automatically and reasonably adjusts the system operation mode and parameters to ensure the stability of the bus DC voltage; through the intelligent operation module, it reads the data of the rotary transformer or proximity switch to calculate the up and down stroke position information of the oil pump, and at the same time collects the inverter unit data to analyze the oil well load situation, and adjusts the working mode of each oil well in real time through load analysis to achieve a balance between the power consumption and power generation status of each oil well, ensuring the normal operation of the system while saving electricity. The execution unit monitors the working status of the city power network, wind power generation equipment, photovoltaic power generation equipment and DC bus in real time, and intelligently controls the power generation power of the green power generation system. It coordinates and controls the balance between the input power and the output power of the power supply through the oil well centralized control unit, and adopts a working mode of giving priority to the use of green electricity and supplementing it with city power to ensure the normal operation of the system. If it is found that the green electricity is still insufficient after all the use, it can automatically draw electricity from the city grid to supplement the electric energy required for the system operation. If the power exceeds the preset value allowed to be fed back to the system grid during operation, it will automatically shut down the input of some green power generation devices such as photovoltaic or wind to ensure that the minimum power of electricity is fed back to the grid, thereby reducing the impact on other equipment in the grid.

[0050] The access method of the original green power generation device is to directly connect the line between the external power grid and the power-consuming equipment. The output fluctuation and unstable current of the green power generation device will pollute the power grid, causing unstable power supply of the power grid, and will have an adverse effect on the normal operation of the motor. The present invention sets a DC bus, connects with the main power grid and the green power generation system to form a well site microgrid, and then connects the power-consuming equipment, so as to achieve effective use of green electric energy while the feedback electric energy of the power generation device will not be sent back to the power grid, and is used for the operation of other oil pumps through the DC bus, eliminating the problem that the frequency and phase of the electricity generated by the power generation device cannot meet the requirements of the power grid and will "pollute" the power grid, thereby reducing interference to the power grid.

[0051] The present invention can be used for a single oil pumping unit, or the motor control cabinets of multiple oil pumping units can be connected in parallel with the DC bus to form a micro-group control system.

[0052] The present invention can realize the "peak-shifting alternation" of the pumping units in the microgrid by precisely controlling the timing of the pumping cycles in the group through intelligent management, thus saving electricity consumption. The micro-storage (energy storage charging and discharging unit) of the group is used to store the trough power generation and the power generated by wind energy and photovoltaics during the "peak-shifting alternation" of the pumping units in the microgrid, and then the inverter unit is used for conversion, effectively isolating the mutual influence between the external power grid and the microgrid of the well site, and effectively protecting the equipment in the well site. The economic and intelligent inter-pumping of the pumping units can be implemented according to the peak and trough electricity prices of the grid electricity and the time of wind and solar power supply. Multiple pumping units are connected in parallel to form a microgrid, which increases the energy storage capacity and realizes 1 to N. It is conducive to overcoming the "pump-up voltage", preventing overvoltage protection from taking effect, and ensuring the safe and stable operation of the equipment, which not only saves electricity but also reduces equipment investment.

[0053] After the present invention was tested and applied in a group of oil pumping units in a certain block of an oil field, the comprehensive electricity saving was ≥10%, the annual electricity bill was saved by 450,000 yuan, and the investment could be recovered in 1.5 years. Practice has proved that the method of the present invention has many advantages such as stable operation, energy saving, and high level of automatic control, and has very high promotion value.

[0054] The embodiments of the present invention have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The selection of terms used herein is intended to best explain the principles of the embodiments, practical applications, or technical improvements in the market, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. An intelligent group control system for microgrid and micro-storage green electricity of oil pumping units, characterized in that: include: Green power generation system, city power grid, inverter unit, DC bus, oil well centralized control unit and execution unit; The mains power grid and the green electricity generation system are connected to the DC bus through the execution unit, and the DC bus is respectively connected to a plurality of pumping units through the inverter unit; The oil well centralized control unit is respectively connected to the execution unit and the inverter unit; The oil well centralized control unit is used to obtain and adjust the real-time power generation energy of the green electricity generation system through the execution unit, and to control the transmission of power from the city power grid and / or the green electricity generation system to the DC bus; The oil well centralized control unit is used to obtain the real-time operating status of the oil pump through the inverter unit, and adjust the real-time power generation energy of the green power generation system and the real-time power consumption of the oil pump during operation to achieve a balance according to the real-time operating status.

2. The intelligent group control system for microgrid and micro-storage green electricity of oil pumping units according to claim 1 is characterized in that: The green electricity generation system includes: an oil pump feedback power generation device, a wind power generation device and a photovoltaic power generation device; The oil pump feedback power generation device, wind power generation device and photovoltaic power generation device are respectively connected to the execution unit. The oil pump feedback power generation device is used to generate electricity by utilizing the downstroke of the oil pump, the wind power generation device is used to generate electricity by converting wind energy into electrical energy, and the photovoltaic power generation device is used to generate electricity by converting solar energy into electrical energy.

3. The intelligent group control system for microgrid and micro-storage green electricity of oil pumping units according to claim 2 is characterized in that: The method of adjusting the real-time power generation energy of the green power generation system according to the operating state to achieve a balance with the real-time power consumption energy of the oil pump during operation includes: The operating state includes: upstroke and downstroke; The oil well centralized control unit collects the operating status of each of the pumping units, and determines whether a first predetermined number of pumping units among all the pumping units are in an upstroke, and a second predetermined number of pumping units are in a downstroke. If not, the oil well centralized control unit adjusts the operating status of the pumping units through the inverter unit, so that the first predetermined number of pumping units are in an upstroke, and the second predetermined number of pumping units are in a downstroke.

4. The intelligent group control system for microgrid and micro-storage green electricity of oil pumping units according to claim 1 is characterized in that: Also includes: Energy storage charging and discharging unit; The energy storage charging and discharging unit is connected to the DC bus and the oil well centralized control unit respectively, and the energy storage charging and discharging unit is used to store or release the electric energy generated by the green electricity generation system.

5. The intelligent group control system for microgrid and micro-storage green electricity of oil pumping units according to claim 4 is characterized by: The oil well centralized control unit is further used to obtain a real-time voltage value on the DC bus, and determine whether the real-time voltage value is greater than the first predetermined voltage value. If so, the oil well centralized control unit controls the energy storage charging and discharging unit to start, and stores part of the current on the DC bus that exceeds the first predetermined voltage value. The oil well centralized control unit is also used to control the energy storage charging and discharging unit to start when it determines that the real-time voltage value is less than a second predetermined voltage value, and transmit the current stored in it into the DC bus, so that the real-time voltage value on the DC bus is equal to the second predetermined voltage value.

6. The intelligent group control system for microgrid and micro-storage green electricity of oil pumping units according to claim 1 is characterized in that: The execution unit includes: a voltage detection module and an AC / DC converter; The voltage detection module is connected to the green electricity generation system and the oil well centralized control unit respectively, and the voltage detection module is used to detect the real-time power generation energy of the green electricity generation system and transmit it to the oil well centralized control unit; The AC / DC converter is connected between the green electricity generation system and the DC bus, and the AC / DC converter is connected to the oil well centralized control unit. The oil well centralized control unit is also used to control the connection or disconnection of the line between the green electricity generation system and the DC bus through the AC / DC converter.

7. The intelligent group control system for oil pumping unit microgrid microstorage green electricity according to claim 1 is characterized in that: The inverter unit includes: a frequency converter and a position detection module; The motor of each oil pump is connected to the DC bus through the corresponding frequency converter, and the frequency converter is used to convert the DC power transmitted by the DC bus into AC power and then transmit it to the corresponding oil pump motor for power supply; The oil well centralized control unit is connected to the frequency converter and the position detection module respectively, and the oil well centralized control unit is also used to detect the real-time operating status of the oil pumping unit through the position detection module.

8. The intelligent group control system for microgrid, microstorage and green electricity of oil pumping units according to any one of claims 1 to 7, characterized in that: The oil well centralized control unit detects the real-time voltage value of the DC bus and determines whether the real-time voltage value of the DC bus is lower than a second predetermined voltage value. If so, the oil well centralized control unit controls the line connection between the mains power grid and the DC bus through the execution unit. If not, the oil well centralized control unit controls the line disconnection between the mains power grid and the DC bus through the execution unit.

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