Photovoltaic-energy storage wellhead heating system and control method

Abstract

The invention relates to a photovoltaic-energy storage wellhead heating system and a control method. The photovoltaic-energy storage wellhead heating system comprises an energy supply unit, a heating unit and a control unit which are connected with one another, wherein the heating unit is used for heating an oil conveying pipeline; the energy supply unit comprises a photovoltaic module and an energy storage module which are connected with each other, and the control unit is used for controlling the photovoltaic module and the energy storage module to switch power supply strategies of the heating unit. The photovoltaic module is adopted to provide electric energy, zero carbon emission is achieved, and the energy storage module is adopted to achieve all-weather operation all year round; the system can be independently arranged and independently operated in an off-grid mode, and complexity and construction cost of a power grid system are reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of petroleum exploration, and in particular relates to a photovoltaic-energy storage wellhead heating system and a control method. Background Art

[0002] The wellhead heating system is indispensable in the surface development and gathering of high-condensate oil and oilfields in cold and alpine areas. It plays an important role in improving the fluidity of crude oil, ensuring the temperature of crude oil entering the station and the output of oil wells. In recent years, with the need for energy conservation and emission reduction, the heating method of oilfield wellheads has transitioned from gas and fuel oil to electric heating, and the use of electric heaters has gradually become more widespread. The current commonly used temperature range of electric heaters is 40℃-70℃. In the prior art, wellhead heating generally uses grid electricity for power supply, which is not conducive to reducing electricity costs; or grid electricity + photovoltaic power supply is used, which still cannot solve the carbon emissions and construction cost problems of grid electricity. Therefore, there is an urgent need for a new wellhead heating system that can operate off-grid, clean and efficient. Summary of the invention

[0003] The purpose of the present invention is to provide a photovoltaic-energy storage wellhead heating system and control method in order to solve the above problems.

[0004] The present invention achieves the above-mentioned purpose through the following technical solutions:

[0005] A photovoltaic-energy storage wellhead heating system comprises an interconnected energy supply unit, a heating unit for heating an oil pipeline and a control unit; the energy supply unit comprises a connected photovoltaic module and an energy storage module, and the control unit is used to control the photovoltaic module and the energy storage module to switch the power supply strategy for the heating unit.

[0006] As a further optimization solution of the present invention, the photovoltaic module is a solar cell panel.

[0007] As a further optimization solution of the present invention, the energy storage module includes a lithium-ion battery, a sodium-ion battery, a flow battery and a supercapacitor.

[0008] As a further optimization solution of the present invention, the heating unit includes a heat-insulating shell, a crude oil inlet and a crude oil outlet are respectively provided at two ends of the heat-insulating shell, and a heating pipe is provided in the heat-insulating shell.

[0009] As a further optimization solution of the present invention, the heating tube is provided with swirl sheets for changing the flow state of crude oil and thus enhancing heat transfer.

[0010] As a further optimization solution of the present invention, a temperature sensor is provided at the crude oil outlet.

[0011] As a further optimization solution of the present invention, the voltage range of the heating unit is 36V-380V.

[0012] A control method for a photovoltaic-energy storage wellhead heating system, comprising:

[0013] Set the target temperature of the heating unit to T, and the power of the heating unit to W;

[0014] When the solar radiation intensity causes the power of the heating unit to be greater than W, the control unit controls the photovoltaic module to supply power to the heating unit and the energy storage module at the same time to ensure that the power of the heating unit is equal to W, and when the capacity of the energy storage module reaches 100%, the current connection between the photovoltaic module and the energy storage module is cut off;

[0015] When the solar radiation intensity causes the power of the heating unit to be less than W, the control unit controls the photovoltaic module and the energy storage module to supply power to the heating unit at the same time to ensure that the power of the heating unit is equal to W;

[0016] When there is no solar radiation, the control unit controls the energy storage module to supply power to the heating unit to ensure that the power of the heating unit is equal to W.

[0017] The beneficial effects of the present invention are:

[0018] The present invention adopts photovoltaic modules to provide electric energy to achieve zero carbon emissions, and adopts energy storage modules to achieve all-year-round all-weather operation; the system can be set up separately and operate independently off-grid, reducing the complexity and construction cost of the power grid system. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0020] Figure 2 It is a structural schematic diagram of the heating unit of the present invention.

[0021] In the figure: 1. Insulation shell; 2. Heating tube; 3. Swirl blade. DETAILED DESCRIPTION

[0022] The present application is further described in detail below in conjunction with the accompanying drawings. It is necessary to point out here that the following specific implementation methods are only used to further illustrate the present application and cannot be understood as limiting the scope of protection of the present application. Technical personnel in this field can make some non-essential improvements and adjustments to the present application based on the above application content.

[0023] like Figure 1 As shown, a photovoltaic-energy storage wellhead heating system includes an interconnected energy supply unit, a heating unit for heating an oil pipeline, and a control unit; the energy supply unit includes a connected photovoltaic module and an energy storage module, and the control unit is used to control the photovoltaic module and the energy storage module to switch the power supply strategy for the heating unit.

[0024] Photovoltaic modules are solar panels.

[0025] The energy storage module is a lithium-ion battery, a sodium-ion battery, a flow battery or a supercapacitor.

[0026] The heating unit includes an insulation shell 1, with a crude oil inlet and a crude oil outlet at both ends of the insulation shell 1, a heating tube 2 is arranged inside the insulation shell 1, and a swirl plate 3 is arranged on the heating tube 2 for changing the flow state of crude oil to enhance heat transfer, and a temperature sensor is arranged at the crude oil outlet. Crude oil flows in from the crude oil inlet and is heated by the heating tube 2; the swirl plate 3 is used to change the flow state of crude oil to make it turbulent and enhance heat transfer; the insulation shell 1 is an insulation layer, which functions as insulation to avoid heat transfer caused by air convection and effectively prevent heat loss. The crude oil temperature in the heating unit is read by the temperature sensor at the crude oil outlet.

[0027] The voltage range of the heating unit is 36V-380V.

[0028] A control method for a photovoltaic-energy storage wellhead heating system, characterized by comprising:

[0029] Set the target temperature of the heating unit to T, and the power of the heating unit to W;

[0030] When the solar radiation intensity causes the power of the heating unit to be greater than W, the control unit controls the photovoltaic module to supply power to the heating unit and the energy storage module at the same time to ensure that the power of the heating unit is equal to W, and when the capacity of the energy storage module reaches 100%, the current connection between the photovoltaic module and the energy storage module is cut off;

[0031] When the solar radiation intensity causes the heating unit power to be less than W, the control unit controls the photovoltaic module and the energy storage module to supply power to the heating unit at the same time to ensure that the heating unit power is equal to W;

[0032] When there is no solar radiation, the control unit controls the energy storage module to supply power to the heating unit to ensure that the power of the heating unit is equal to W.

[0033] In this embodiment, a photovoltaic-energy storage wellhead heating system includes the following energy supply unit, heating unit, control unit and corresponding connecting lines;

[0034] The energy supply unit includes a photovoltaic module and an energy storage module, wherein the photovoltaic module is a solar panel and the energy storage module is a lithium-ion battery;

[0035] The heating unit includes a crude oil inlet, a heat preservation shell, a heating tube, a swirl sheet, and a crude oil outlet, and the voltage range is 220V;

[0036] The control unit is responsible for controlling the power supply strategy switching of the energy supply unit. The specific control strategy is:

[0037] Set the heating unit target temperature to 65°C and the power to 10kW.

[0038] a. When the solar radiation intensity is high and the power of the heating unit is greater than 10kW, the control unit controls the photovoltaic module to supply power to the heating unit and the energy storage module at the same time to ensure that the power of the heating unit is equal to 10kW, and when the capacity of the energy storage module reaches 100%, the current connection between the photovoltaic module and the energy storage module is cut off;

[0039] b. The solar radiation intensity is low and the power of the heating unit is less than 10kW. The control unit controls the photovoltaic module and the energy storage module to supply power to the heating unit at the same time to ensure that the power of the heating unit is equal to 10kW;

[0040] c. When there is no solar radiation, the control unit controls the energy storage module to supply power to the heating unit to ensure that the power of the heating unit is equal to 10kW.

[0041] The photovoltaic-energy storage wellhead heating system and control method can achieve off-grid operation all year round, with a heating power of 10kW, a temperature of 65°C, and an export crude oil temperature greater than 60°C.

[0042] The purpose of the present invention is to develop a new wellhead heating system that is off-grid, clean and efficient. In view of the problems of large carbon emissions and high comprehensive costs of traditional wellhead heating systems, a photovoltaic-energy storage system is used to replace the traditional electric heating system to achieve off-grid operation, thereby comprehensively reducing the cost and carbon emissions of oilfield wellhead heating.

[0043] The above embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present invention. It should be pointed out that, for those of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention.

Claims

1. A photovoltaic-energy storage wellhead heating system, characterized in that: It includes an interconnected energy supply unit, a heating unit for heating the oil pipeline and a control unit; the energy supply unit includes a connected photovoltaic module and an energy storage module, and the control unit is used to control the photovoltaic module and the energy storage module to switch the power supply strategy for the heating unit.

2. A photovoltaic-energy storage wellhead heating system according to claim 1, characterized in that: The photovoltaic module is a solar panel.

3. A photovoltaic-energy storage wellhead heating system according to claim 1, characterized in that: The energy storage modules include lithium-ion batteries, sodium-ion batteries, flow batteries and supercapacitors.

4. A photovoltaic-energy storage wellhead heating system according to claim 1, characterized in that: The heating unit comprises a heat-insulating shell (1), a crude oil inlet and a crude oil outlet are respectively arranged at two ends of the heat-insulating shell (1), and a heating pipe (2) is arranged inside the heat-insulating shell (1).

5. A photovoltaic-energy storage wellhead heating system according to claim 4, characterized in that: The heating tube (2) is provided with a swirl sheet (3) for changing the flow state of crude oil and thereby enhancing heat transfer.

6. A photovoltaic-energy storage wellhead heating system according to claim 4, characterized in that: A temperature sensor is provided at the crude oil outlet.

7. A photovoltaic-energy storage wellhead heating system according to claim 1, characterized in that: The voltage range of the heating unit is 36V-380V.

8. A control method for a photovoltaic-energy storage wellhead heating system according to any one of claims 1 to 7, characterized in that: include: Set the target temperature of the heating unit to T, and the power of the heating unit to W; When the solar radiation intensity causes the power of the heating unit to be greater than W, the control unit controls the photovoltaic module to supply power to the heating unit and the energy storage module at the same time to ensure that the power of the heating unit is equal to W, and when the capacity of the energy storage module reaches 100%, the current connection between the photovoltaic module and the energy storage module is cut off; When the solar radiation intensity causes the power of the heating unit to be less than W, the control unit controls the photovoltaic module and the energy storage module to supply power to the heating unit at the same time to ensure that the power of the heating unit is equal to W; When there is no solar radiation, the control unit controls the energy storage module to supply power to the heating unit to ensure that the power of the heating unit is equal to W.

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