Downhole lifting energy storage tubing string, downhole monitoring system and downhole lifting energy storage method

Abstract

Provided are a downhole lifting energy storage tubing string, a downhole monitoring system and a downhole lifting energy storage method, belonging to oil extraction in oil fields. The downhole lifting energy storage tubing string comprises a sucker rod (1), a power generation body (3) and an energy storage body (6). The power generation body comprises a mover assembly (31) and a stator assembly (32). The mover assembly is fixedly sleeved on the sucker rod, and the stator assembly is sleeved on the outside of the mover assembly, the length of the mover assembly being greater than the length of the stator assembly. The stator assembly is provided with a stator coil winding (322). The sucker rod can reciprocate in the tubing string, the mover assembly generates a radial magnetic field along with the reciprocating motion of the sucker rod, and the stator coil winding of the stator assembly generates induced current under the action of the radial magnetic field. The energy storage body is connected to the power generation body and is used for receiving the induced current from the power generation body to obtain electric energy and store the electric energy.

Description

Downhole lifting energy storage string, downhole monitoring system and downhole lifting energy storage method Technical Field

[0001] The present invention relates to the technical field of oil field production, and in particular to a downhole lifting energy storage string, a downhole monitoring system and a downhole lifting energy storage method. Background Art

[0002] During oil well production, the primary lifting method is pumping units. Wax buildup in pumping units can clog the oil flow path, increase wellhead back pressure, reduce well production, and increase well load, severely impacting normal production. Currently, three main methods for oil well dewaxing and paraffin prevention are hot washing, chemical dosing, and electric heating. However, these methods present the following challenges: First, the average hot washing cycle is short, the cost of a single hot wash is high, and the annual loss of production time per well due to drainage is 10-22 days. Second, the annual chemical dosing volume per well for wax deposition is high, resulting in high costs and increased costs for subsequent crude oil dehydration, reducing the production time per well. Third, electric heating for dewaxing and paraffin removal consumes a lot of energy. Resistive heating is limited in depth and expensive due to the strength of the carbon fiber rod and the varying downhole lifting load. Electromagnetic heating, on the other hand, has complex operational procedures, high implementation costs, and is not suitable for large-scale application. In recent years, the existing technology has been improved year by year through a number of measures such as new lifting and efficiency improvement of old wells. The energy saving and consumption reduction level of mechanical mining systems has been improved year by year. However, the high energy consumption per ton of liquid and high total cost are still serious on site. There is an urgent need for the research and development of new process technologies to achieve cost reduction and efficiency improvement in oilfield development.

[0003] Furthermore, by 2050, 25% of incremental growth and one-third of cost reductions in the oil and gas industry will be achieved through digitalization. Oil and gas companies will increasingly rely on information technology to increase reserves and production. Currently, acquiring downhole parameters is subject to high monitoring costs and large errors. Downhole cable testing is complex and expensive, while cableless testing relies on internal batteries with short lifespans, making real-time downhole monitoring impossible. This results in poor judgment of downhole conditions and insufficient intelligent oil production.

[0004] Summary of the Invention

[0005] In order to solve the above-mentioned technical defects, the present invention provides a downhole lifting energy storage string, a downhole monitoring system and a downhole lifting energy storage method. The downhole lifting energy storage string uses the idle mechanical energy of the sucker rod when it is descending to realize the conversion of mechanical energy, magnetic energy and electrical energy under the action of a generator, and stores the electrical energy in the energy storage body.

[0006] A first aspect of the present invention provides a downhole lifting energy storage string, comprising: a sucker rod, a generator and an energy storage body, wherein the generator comprises a mover assembly and a stator assembly;

[0007] The movable assembly is fixedly sleeved on the sucker rod, the stator assembly is sleeved outside the movable assembly, and the length of the movable assembly is greater than the length of the stator assembly;

[0008] The stator assembly is provided with a stator coil winding;

[0009] The sucker rod can reciprocate in the tubing string, the mover assembly generates a radial magnetic field as the sucker rod reciprocates, and the stator coil winding of the stator assembly generates an induced current under the action of the radial magnetic field;

[0010] The energy storage body is connected to the power generation body and is used to receive the induced current from the power generation body to obtain electric energy and store it.

[0011] In an embodiment of the present invention, the downhole lifting energy storage string further comprises: a loading mechanism,

[0012] The load mechanism is electrically connected to the energy storage body and is used to utilize the electrical energy of the energy storage body.

[0013] In an embodiment of the present invention, the load mechanism is a heating component;

[0014] The heating component is installed at the wax deposition point of the downhole lifting energy storage pipe string and is used for heating and removing wax.

[0015] In an embodiment of the present invention, the load mechanism is a signal transmitter;

[0016] The signal transmitter is connected to the signal receiver on the well and is used to transmit the downhole test signal.

[0017] In an embodiment of the present invention, the sucker rod includes a first sucker rod and a second sucker rod connected in sequence, the second sucker rod has a hollow oil channel, and the mover assembly is fixedly sleeved on the second sucker rod.

[0018] In an embodiment of the present invention, the downhole lifting energy storage string further includes an inner ring flow support, which is fixedly mounted on the sucker rod and is also fixedly connected to the mover assembly.

[0019] In an embodiment of the present invention, the mover assembly includes: a mover inner tube, a mover magnetic steel assembly, a mover retaining ring, and a magnetic steel spacer ring;

[0020] The inner tube of the mover is sleeved on the sucker rod and fixed to the inner ring flow support;

[0021] The mover magnetic steel assembly is sleeved on the mover inner tube;

[0022] The mover retaining ring is sleeved on the mover inner tube and is arranged at the end of the mover inner tube, and is used to fix the mover magnetic steel assembly;

[0023] The magnetic steel spacer ring is arranged between two adjacent mover magnetic steel assemblies.

[0024] In an embodiment of the present invention, the mover magnetic steel assembly includes: the mover magnetic steel assembly includes: magnetic steel and a magnetic steel protection ring;

[0025] The magnetic steel is sleeved on the inner tube of the mover;

[0026] The magnetic steel protection ring is installed on the side of the magnetic steel away from the inner tube of the mover.

[0027] In an embodiment of the present invention, the stator assembly includes a white steel liner, a stator coil winding, and a stator retaining ring;

[0028] The stator coil winding is wound on the white steel liner;

[0029] The stator retaining ring is connected to the white steel liner, and the stator retaining ring is used to fix the stator coil winding.

[0030] In an embodiment of the present invention, the stator coil winding comprises: the stator coil winding comprises: a coil winding, an insulating sheet, a coil spacer ring and a silicon steel sheet;

[0031] The coil spacer is attached to the white steel liner;

[0032] The coil winding is wound on the coil spacer ring;

[0033] The insulating sheets are arranged on both sides of the coil winding;

[0034] A plurality of silicon steel sheets are overlapped and arranged between the insulating sheets of two adjacent coil windings.

[0035] In an embodiment of the present invention, the generator further comprises: an upper generator connector, a lower generator connector, and a generator energy storage connector;

[0036] The upper joint of the generator is sleeved outside the movable assembly and fixedly connected to the upper end of the stator assembly;

[0037] The lower joint of the generator is sleeved outside the movable assembly and fixedly connected to the lower end of the stator assembly;

[0038] The generator energy storage connector is connected to the generator lower connector.

[0039] In the embodiment of the present invention, the energy storage body includes an energy storage body connector, an energy storage body tube, an energy storage body tube, an energy storage body energy storage assembly, and an energy storage body electric control connector;

[0040] The energy storage body inner tube, the energy storage body outer tube, the energy storage body connector and the energy storage body electric control connector form an energy storage cavity, the energy storage body connector is installed at the upper end of the energy storage cavity and is respectively connected to the energy storage body inner tube and the energy storage body outer tube, the energy storage body electric control connector is installed at the lower end of the energy storage cavity and is respectively connected to the energy storage body inner tube and the energy storage body outer tube, and the energy storage assembly of the energy storage body is arranged in the energy storage cavity;

[0041] The energy storage body connector is also connected to the generator energy storage connector of the generator.

[0042] In an embodiment of the present invention, the energy storage body further includes an energy storage body cable connector, and the energy storage body cable connector is installed on the energy storage body connector.

[0043] In an embodiment of the present invention, the downhole lifting energy storage string further includes an electric control body, which includes an electric control outer tube, an electric control inner tube, an electric control component, and an electric control load connector;

[0044] The energy storage body electric control connector, the electric control outer tube, the electric control inner tube and the electric control load connector form an electric control cavity. The energy storage body electric control connector is installed at the upper end of the electric control cavity and is respectively connected to the electric control inner tube and the electric control outer tube. The electric control load connector is installed at the lower end of the electric control cavity and is respectively connected to the electric control inner tube and the electric control outer tube. The electric control component is placed in the electric control cavity.

[0045] In an embodiment of the present invention, the load mechanism includes a load assembly, a load mechanism outer tube, a load mechanism inner tube, and a lower joint;

[0046] The electrically controlled load connector, the load mechanism inner tube, the load mechanism outer tube, and the lower connector form a load cavity. The load assembly is mounted on the upper end of the load cavity and is connected to the load mechanism inner tube and the load mechanism outer tube, respectively. The lower connector is mounted on the lower end of the load cavity and is connected to the load mechanism inner tube and the load mechanism outer tube, respectively. The load assembly is placed in the load cavity.

[0047] In an embodiment of the present invention, the downhole lifting energy storage string further includes an oil pipe coupling, and the lower end of the oil pipe coupling is connected to the upper joint of the generator.

[0048] A second aspect of the present invention provides a downhole monitoring system, comprising a signal receiver, a monitoring sensor, and the downhole lifting energy storage string as described above;

[0049] The signal receiver is communicatively connected to the signal transmitter in the downhole lifting energy storage string;

[0050] The monitoring sensor is connected to the signal transmitter and is used to provide a monitoring signal to the signal transmitter.

[0051] In an embodiment of the present invention, the monitoring sensor includes a temperature sensor and a pressure sensor.

[0052] In an embodiment of the present invention, the monitoring sensor is connected to the energy storage body of the downhole lifting energy storage string, and the energy storage body provides electrical energy to the monitoring sensor.

[0053] A third aspect of the present invention provides a downhole lifting and energy storage method, which is applied to the downhole lifting and energy storage string as described above, and comprises:

[0054] The pumping rod drives the moving element of the generator to reciprocate to generate electricity;

[0055] The generated electrical energy is stored in an energy storage body.

[0056] The downhole lifting energy storage string provided by the present invention can realize the conversion of mechanical energy, magnetic energy and electrical energy under the action of the generator by utilizing the idle mechanical energy of the sucker rod when it is descending, and store the electrical energy in the energy storage body.

[0057] Other features and advantages of the technical solution of the present invention will be described in detail in the specific implementation section below. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0059] FIG1 is a schematic structural diagram of a downhole lifting energy storage string provided by an embodiment of the present invention;

[0060] FIG2 is a schematic structural diagram of an inner string of a downhole lifting energy storage string provided by an embodiment of the present invention;

[0061] FIG3 is a schematic structural diagram of an outer string of a downhole lifting energy storage string provided by an embodiment of the present invention;

[0062] FIG4 is a schematic structural diagram of a mover magnetic steel assembly provided in an embodiment of the present invention;

[0063] FIG5 is a schematic structural diagram of a magnetic steel provided in an embodiment of the present invention;

[0064] FIG6 is a schematic structural diagram of a stator assembly provided in an embodiment of the present invention;

[0065] 7 is a schematic structural diagram of a stator coil winding according to an embodiment of the present invention;

[0066] FIG8 is a simplified structural diagram of a downhole lifting energy storage string provided by an embodiment of the present invention.

[0067] Explanation of the reference numerals 1- sucker rod, 11- first sucker rod, 12- second sucker rod, 2- oil pipe coupling, 3- generator, 31- mover assembly, 311- mover retaining ring, 312- mover magnetic steel assembly, 313- magnetic steel spacer ring, 3131- magnetic steel, 3132- magnetic steel protection ring, 314- mover inner tube, 32- stator assembly, 321- stainless steel liner, 322- stator coil winding, 3221- coil winding, 3222- insulating sheet, 3223- coil spacer ring, 3224- silicon steel sheet, 323- stator retaining ring, 33- generator upper joint, 34- generator lower joint, 35- generator Energy storage connector, 36-generator body outer tube, 4-inner ring current support, 5-load mechanism, 51-heating component, 52-signal transmitter, 53-load component, 54-load mechanism outer tube, 55-load mechanism inner tube, 56-lower connector, 6-energy storage body, 61-energy storage body connector, 62-energy storage body outer tube, 63-energy storage body outer tube, 64-energy storage body energy storage component, 65-energy storage body electric control connector, 66-energy storage body cable connector, 7-electric control body, 71-electric control outer tube, 72-electric control inner tube, 73-electric control component, 74-electric control load connector, 8-upper sealing ring, 9-lower sealing ring, 10-oil pipe. DETAILED DESCRIPTION

[0068] To make the technical solutions and advantages of the embodiments of the present invention more clearly understood, exemplary embodiments of the present invention are further described in detail below with reference to the accompanying drawings. It should be noted that the embodiments described are only a portion of the embodiments of the present invention, and are not an exhaustive list of all embodiments. It should be noted that the embodiments of the present invention and the features thereof may be combined with each other unless they conflict.

[0069] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0070] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature specified as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0071] In the present invention, unless otherwise expressly specified or limited, terms such as "mounted," "connected," "connect," and "fixed" should be understood broadly. For example, they may refer to fixed or detachable connections, or integration; mechanical or electrical connections, or communication; direct or indirect connections through an intermediate medium; and internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0072] During the process of realizing the present invention, the inventors discovered that during oil well production, the main lifting method is pumping unit lifting. This causes wax deposition in pumping units to clog the oil outlet, increase wellhead back pressure, reduce oil well production, and increase oil well load, seriously hindering normal oil well production. Currently, there are three main methods for oil well cleaning and wax prevention: hot washing, chemical dosing, and electric heating. However, these methods have the following problems: First, the average hot washing cycle is short, and the cost of a single hot washing is high. Due to drainage, the annual production loss rate for a single well is 10-22 days per well. Second, the annual chemical dosing volume for a wax-deposited well is large, which is expensive and increases the cost of subsequent crude oil dehydration. Third, electric heating for wax removal consumes a lot of energy, making it impossible to implement large-scale application. Furthermore, the measurement of downhole parameters such as temperature, pressure, and flow currently relies on cables or optical fibers to power downhole sensors and collect data, which is costly and places high demands on the downhole space size design. Pre-embedded batteries used for downhole sensors generally have a short battery life and cannot meet the requirements for long-term collection of downhole parameters such as temperature, pressure, and flow. Therefore, there is an urgent need for a new process and method that can realize the low-cost cleaning and wax prevention of pumping wells and the transmission of downhole temperature and pressure signals, reduce operating costs, and improve operating efficiency. At the same time, the accurate acquisition of downhole temperature and pressure signals can realize the adjustment of stroke and stroke frequency of ground equipment such as pumping units, helping to realize intelligent oil production in oil fields.

[0073] In response to the above problems, an embodiment of the present invention provides a downhole lifting energy storage string, comprising: a sucker rod, a generator, and an energy storage body, wherein the generator includes a mover assembly and a stator assembly; the mover assembly is fixedly mounted on the sucker rod, and the stator assembly is mounted outside the mover assembly, the length of the mover assembly being greater than the length of the stator assembly; the stator assembly is provided with a stator coil winding; the sucker rod can reciprocate within the string, the mover assembly generates a radial magnetic field as the sucker rod reciprocates, and the stator coil winding of the stator assembly generates an induced current under the action of the radial magnetic field; the energy storage body is connected to the generator, and is used to receive the induced current from the generator to obtain and store electrical energy. The downhole lifting energy storage string provided by the present invention can achieve the conversion of mechanical energy, magnetic energy, and electrical energy under the action of the generator by utilizing the idle mechanical energy of the sucker rod during its downward movement, and store the electrical energy in the energy storage body.

[0074] FIG1 is a schematic structural diagram of a downhole lifting energy storage string provided by an embodiment of the present invention.

[0075] FIG2 is a schematic structural diagram of an inner string of a downhole lifting energy storage string provided by an embodiment of the present invention.

[0076] FIG3 is a schematic structural diagram of an outer string of a downhole lifting energy storage string provided by an embodiment of the present invention.

[0077] As shown in Figures 1-3, a downhole lifting energy storage string provided in this embodiment includes: a sucker rod 1, a generator 3 and an energy storage body 6, wherein the generator 3 includes a mover assembly 31 and a stator assembly 32;

[0078] The movable assembly 31 is fixedly mounted on the sucker rod 1 , and the stator assembly 32 is mounted outside the movable assembly 31 . The length of the movable assembly 31 is greater than that of the stator assembly 32 .

[0079] The stator assembly 32 includes an induction coil;

[0080] The sucker rod 1 can reciprocate in the tubing string, and the mover assembly 31 generates a radial magnetic field as the sucker rod 1 reciprocates. The induction coil of the stator assembly 32 generates an induced current under the action of the radial magnetic field.

[0081] The energy storage body 6 is connected to the power generation body 3 and is used to receive the induced current from the power generation body 3 to obtain electrical energy and store it.

[0082] The load mechanism 5 is electrically connected to the energy storage body 6 and is used to utilize the electrical energy of the energy storage body 6 .

[0083] Furthermore, the load mechanism 5 utilizes the electrical energy of the energy storage body 6 to heat the oil pipe 10 in the pipe string, thereby clearing and preventing paraffin from the oil pipe 10. The load mechanism 5 is also used to supply electrical energy during downhole testing, thereby transmitting test signals.

[0084] In this embodiment, the load mechanism 5 is a heating component 51 , which is installed at the wax deposition point of the oil pipe 10 for heating and removing wax.

[0085] In this embodiment, the load mechanism 5 is a signal transmitter 52 , which is connected to a signal receiver on the well and is used to transmit a downhole test signal.

[0086] In this embodiment, the sucker rod 1 includes a first sucker rod 11 and a second sucker rod 12 connected in sequence. The first sucker rod 11 is a conventional sucker rod 1, and the second sucker rod 12 has a hollow oil channel.

[0087] The upper and lower ends of the second sucker rod 12 have sucker rod 1 threads. The upper end is connected to the multi-stage first sucker rod 11 and then to the wellhead polished rod. The lower end is connected to the multi-stage first sucker rod 11 and then to the oil pump plunger.

[0088] In this embodiment, the downhole lifting energy storage string further includes an inner ring flow support 4, which is fixedly mounted on the sucker rod 1 and is also fixedly connected to the mover assembly 31. Specifically, the inner flow ring support is fixed to the thin-diameter rod body of the sucker rod 1, with 3-5 inner flow ring supports evenly distributed around the circumference and fixed by welding. Multiple inner flow ring supports are evenly distributed axially on the sucker rod 1, all of which are fixed by welding. At the same time, the inner flow ring support is welded to the mover assembly 31, thereby forming a downhole oil flow lifting channel composed of the sucker rod 1, the inner flow ring support, and the inner diameter of the mover assembly 31, which satisfies the lifting requirements of a multi-pump type oil pump.

[0089] In this embodiment, the generator 3 further includes: a generator upper connector 33, a generator lower connector 34 and a generator energy storage connector 35;

[0090] The generator upper connector 33 is sleeved outside the mover assembly 31 and fixedly connected to the upper end of the stator assembly 32;

[0091] The generator lower connector 34 is sleeved outside the mover assembly 31 and fixedly connected to the lower end of the stator assembly 32;

[0092] The generator energy storage connector 35 is connected to the generator lower connector 34 .

[0093] Furthermore, the generator 3 further includes a generator outer tube 36 , which is used to encapsulate the generator upper connector 33 , the generator lower connector 34 , the generator energy storage connector 35 and the stator assembly 32 .

[0094] FIG4 is a schematic structural diagram of a mover magnetic steel assembly provided in an embodiment of the present invention.

[0095] Figure 5 is a schematic diagram of the structure of the magnetic steel provided in an embodiment of the present invention. As shown in Figures 4-5, in this embodiment, the mover assembly 31 includes a mover inner tube 314, a mover magnetic steel assembly 312, a mover retaining ring 311, and a magnetic steel spacer ring 313;

[0096] The mover inner tube 314 is sleeved on the sucker rod 1 and fixed to the inner ring flow support 4;

[0097] The mover magnetic steel assembly 312 is sleeved on the mover inner tube 314;

[0098] The mover retaining ring 311 is sleeved on the mover inner tube 314 and is provided at the end of the mover inner tube 314 to fix the mover magnetic steel assembly 312;

[0099] The magnetic steel spacer ring 313 is disposed between two adjacent mover magnetic steel assemblies 312 .

[0100] The magnetic steel spacer ring is made of stainless steel and has a rotating body structure. Since the magnet is tile-type and the length of a single magnet is limited, a magnetic steel spacer ring is required between every two magnets to achieve high magnetic permeability and non-magnetic blocking.

[0101] The mover magnetic steel assembly 312 includes: a magnetic steel 3131 and a magnetic steel protection ring 3132;

[0102] The magnetic steel 3131 is sleeved on the inner tube 314 of the mover;

[0103] The magnetic steel protection ring 3132 is installed on the side of the magnetic steel 3131 away from the mover inner tube 314 .

[0104] Specifically, the mover retaining ring 311, mover magnetic steel assembly 312, and magnetic steel spacer ring 313 are sequentially inserted into the lift mover inner tube 314 and fixed at both ends by welding. The entire lift mover assembly 31 is composed of multiple groups of mover magnetic steel assemblies 312 and magnetic steel spacer rings 313. The mover magnetic steel assembly 312 mainly includes magnetic steel 3131 and magnetic steel protection ring 3132. The magnetic steel 3131 is evenly distributed around the circumference, realizing the north and south magnetic poles relative to each other, thereby forming a radial magnetic field.

[0105] The mover assembly 31 is fixed to the sucker rod 1 with an internal flow ring, forming a single unit. The upper sealing ring 8 is designed with multiple O-ring grooves on both the inner and outer diameters to provide a seal. It is inserted into the upper connector 33 of the generator and threadedly connected to the outer tube of the lifting generator. Multiple through-holes are designed around the upper sealing ring 8. Once the lifting generator is assembled, these holes are used to inject sealing grease, ensuring overall insulation and waterproofing.

[0106] FIG6 is a schematic structural diagram of a stator assembly provided in an embodiment of the present invention.

[0107] Figure 7 is a schematic diagram of the structure of the stator coil winding provided in an embodiment of the present invention. As shown in Figures 6-7, in this embodiment, the stator assembly 32 includes: a white steel liner 321, a stator coil winding 322, and a stator retaining ring 323;

[0108] The stator coil winding 322 is wound on the white steel liner 321;

[0109] The stator retaining ring 323 is connected to the white steel liner 321 , and the stator retaining ring 323 is used to fix the stator coil winding 322 .

[0110] The stator coil winding 322 includes: a coil winding 3221, an insulating sheet 3222, a coil spacer ring 3223 and a silicon steel sheet 3224;

[0111] The coil spacer ring 3223 is attached to the white steel liner 321; the coil spacer ring is used as an integrated design of the coil winding frame and the stator coil.

[0112] The coil winding 3221 is wound on the coil spacer ring 3223.

[0113] The insulating sheets 3222 are provided on both sides of the coil winding 3221;

[0114] A plurality of silicon steel sheets 3224 are overlapped and arranged between the insulating sheets 3222 of two adjacent coil windings 3221. The silicon steel sheets are used to enhance the magnetic induction strength.

[0115] Furthermore, the inner diameter of the stator retaining ring 323 is designed with a thread, which is threadedly connected and fixed to the white steel liner 321. After the multi-stage stator coil winding 322 is sequentially inserted, the end is fixed with the stator retaining ring 323.

[0116] The coil winding 3221 mainly includes an insulating sheet 3222, a coil winding 3221, a silicon steel sheet 3224, and a coil spacer ring 3223. The insulating sheet 3222 is provided on both sides of the coil winding 3221 for insulation. The coil winding 3221 is wound around the coil spacer ring 3223, with the number of turns determined by the design. The silicon steel sheet 3224 is composed of multiple sub-silicon steel sheets 3224.

[0117] Specifically, the single-stage stator coil winding 322 is designed to be wound with 0.5mm wire to form 1280 turns, achieving a single-stage generated voltage of 54V. By connecting multiple stator coil windings 322 in series, a generated voltage of 540V and above is achieved, which is used to store energy in the energy storage component 64 of the energy storage body. At the same time, a group of stator coil windings 322 is drawn out to generate a 24V voltage for control of the electronic control body 7.

[0118] The generator's upper connector 33 maintains the same internal diameter as the stator assembly 32, maintaining a 3-5mm gap with the stator assembly's outer diameter. Three to five inner ring flow supports 4 are fixed to the thin rod of the sucker rod 1, evenly spaced around the circumference and secured by welding. Multiple inner flow ring supports are evenly spaced axially on the sucker rod 1 and secured by welding. The inner ring flow supports 4 are also welded to the mover assembly 31. Thus, the sucker rod 1, inner ring flow supports 4, and the inner diameter of the mover assembly 31 form a downhole oil flow lift channel. The equivalent annulus aperture of this lift channel is designed to be ≥φ20mm, allowing for multi-pump oil well pump lift without throttling.

[0119] One end of the generator lower connector 34 is a tubing buckle, which connects and seals with the generator energy storage connector 35. Its outer diameter is designed with multiple O-ring grooves, which provide an O-ring seal with the lower sealing ring 9. The other end is designed with a threaded buckle, which is threadedly connected to and secured to the stator assembly 32. The lower sealing ring 9, also designed with multiple O-ring grooves on its outer diameter, provides a seal. It fits over the generator lower connector 34 and is threadedly connected to the generator outer tube 36. Multiple through-holes are designed around the circumference of the lower sealing ring 9. Once the generator 3 is assembled, sealing grease is injected through these holes to provide overall insulation and waterproofing. Cables are also routed through these holes to the energy storage element 6 for charging.

[0120] The outer diameter of the mover assembly 31 is designed to maintain a clearance of 3-5mm from the inner diameter of the stator assembly 32, ensuring that it is as close to the stator assembly 32 as possible to maximize the utilization of magnetic field energy. Because the magnetic energy of a magnetic field decreases inversely with distance, the inner diameter of the stator assembly 32 must be designed to ensure that it does not throttle the oil flow from the downhole pump. The length of the mover assembly 31 must be designed to account for the weight-dependent elongation of the entire tubing string. The mover assembly 31 is longer than the stator assembly 32 to ensure uninterrupted power generation by the stator assembly 32 and maximize the utilization of the entire tubing string.

[0121] The downhole lifting energy storage string also includes an upper sealing ring 8. The inner and outer diameters of the upper sealing ring 8 are designed with multiple O-ring grooves to play a sealing role. It is inserted into the upper joint 33 of the generator and is threadedly connected to the outer power generation pipe. The upper sealing ring 8 is designed with 4-6 through holes on its circumference. When the generator 3 is assembled, sealing grease is injected through these holes to achieve overall insulation and waterproofing.

[0122] Oil pipe buckles are designed at both ends of the generator energy storage joint 35. The upper end is connected and sealed with the oil pipe buckle of the generator lower joint 34, and the lower end is connected and sealed with the oil pipe buckle of the energy storage body joint 61. The generator energy storage joint 35 is designed with multiple through holes for lifting the power generation lead-out line through the wire trough.

[0123] In this embodiment, the energy storage body 6 includes an energy storage body connector 61, an energy storage body inner tube 62, an energy storage body outer tube 63, an energy storage body energy storage assembly 64 and an energy storage body electrical control connector 65. The energy storage body inner tube 62, the energy storage body outer tube 63, the energy storage body connector 61 and the energy storage body electrical control connector 65 form an energy storage cavity. The energy storage body connector 61 is installed at the upper end of the energy storage cavity and is respectively connected to the energy storage body inner tube 62 and the energy storage body outer tube 63. The energy storage body electrical control connector 65 is installed at the lower end of the energy storage cavity and is respectively connected to the energy storage body inner tube 62 and the energy storage body outer tube 63. The energy storage body energy storage assembly 64 is arranged in the energy storage cavity.

[0124] The energy storage body connector 61 is also connected to the generator energy storage connector 35 of the generator 3 .

[0125] In this embodiment, the energy storage body 6 further includes an energy storage body cable connector 66 , and the energy storage body cable connector 66 is installed on the energy storage body connector 61 .

[0126] Specifically, the left and right inner diameters of the energy storage body joint 61 are designed with oil pipe buckles, the upper end is connected and sealed to the generator energy storage joint 35, and the lower end is connected and sealed to the energy storage body inner tube 62. The outer diameter of the right end of the energy storage body joint 61 is designed with multiple O-ring grooves, and the left end face of the energy storage body joint 61 is designed with a cable connector mounting hole, which is sealed with an O-ring after the energy storage body cable joint 66 is connected.

[0127] The energy storage body inner tube 62 is designed as a conventional oil pipe 10, with oil pipe threaded at the top and bottom. It is threadedly connected to the energy storage body connector 61 and the energy storage body electrical control connector 65, respectively, and sealed. The energy storage body outer tube 63 is inserted into the energy storage body connector 61 and sealed with an O-ring. The energy storage body energy storage assembly 64 is installed in the cavity formed by the energy storage body connector 61, the energy storage body inner tube 62, the energy storage body outer tube 63, and the energy storage body electrical control connector 65, and is used to store the electrical energy of the lifting and power generation part.

[0128] Oil pipe buckle threads are designed at both ends of the inner diameter of the energy storage body electric control connector 65, which are respectively connected and sealed with the oil pipe buckles of the energy storage body inner tube 62 and the electric control inner tube 72. Multiple O-ring sealing grooves are designed at both ends of the outer diameter, which are respectively sealed with the O-rings of the energy storage body outer tube 63 and the electric control outer tube 71. Multiple channels are designed on the circumference of the end face of the energy storage body electric control connector 65 for the passage of the energy storage component cables, thereby controlling the electric control component 73.

[0129] In this embodiment, the downhole lifting energy storage string also includes an electrically controlled body 7, which includes an electrically controlled outer tube 71, an electrically controlled inner tube 72, an electrically controlled component 73 and an electrically controlled load connector 74. The energy storage body electrically controlled connector 65, the electrically controlled outer tube 71, the electrically controlled inner tube 72 and the electrically controlled load connector 74 form an electrically controlled cavity. The energy storage body electrically controlled connector 65 is installed at the upper end of the electrically controlled cavity and is respectively connected to the electrically controlled inner tube 72 and the electrically controlled outer tube 71. The electrically controlled load connector 74 is installed at the lower end of the electrically controlled cavity and is respectively connected to the electrically controlled inner tube 72 and the electrically controlled outer tube 71. The electrically controlled component 73 is placed in the electrically controlled cavity.

[0130] Specifically, the inner control tube 72 is designed with oil pipe clips at both ends, which are used to connect and seal the oil pipe clips to the energy storage body electric control connector 65 and the electric control load connector 74, respectively. The outer control tube 71 is sealed to the energy storage body electric control connector 65 and the electric control load connector 74 using O-rings. The electric control assembly 73 is installed in the cavity formed by the inner control tube 72, the energy storage body electric control connector 65, the outer control tube 71, and the electric control load connector 74.

[0131] Oil pipe buckle threads are designed at both ends of the inner diameter of the electronically controlled load connector 74, which are respectively connected and sealed with the oil pipe buckles of the electronically controlled inner tube 72 and the load mechanism inner tube 55. Multiple O-ring sealing grooves are designed at both ends of the outer diameter, which are respectively sealed with the O-rings of the electronically controlled outer tube 71 and the load mechanism outer tube 54. Multiple channels are designed on the circumference of the end face of the electronically controlled load connector 74 for the passage of the cables of the electronically controlled component 73, thereby controlling the load component 53.

[0132] In this embodiment, the load mechanism 5 includes a load component 53, a load mechanism outer tube 54, a load mechanism inner tube 55 and a lower joint 56. The electronically controlled load joint 74, the load mechanism inner tube 55, the load mechanism outer tube 54 and the lower joint 56 form a load cavity. The load component 53 is installed at the upper end of the load cavity and is respectively connected to the load mechanism inner tube and the load mechanism outer tube. The lower joint 56 is installed at the lower end of the load cavity and is respectively connected to the load mechanism inner tube and the load mechanism outer tube. The load component 53 is placed in the load cavity.

[0133] Furthermore, the present invention has multiple loading mechanisms 5, corresponding to multiple loading cavities. The loading component 53 includes a heating component 51 and a signal generator 52, and the heating component 51 and the signal generator 52 are respectively installed in different loading cavities.

[0134] The inner diameter ends of the lower joint 56 are designed with oil pipe buckle threads, the upper end is connected and sealed with the oil pipe buckle of the load mechanism inner tube 55, and the outer diameter is designed with multiple O-ring grooves, which are sealed with O-rings on the load mechanism outer tube 54. The lower end of the lower joint 56 is connected and sealed with the oil pipe buckle of the ordinary oil pipe 10.

[0135] In this embodiment, the downhole lifting energy storage string further includes an oil pipe 10 coupling 2 , and the lower end of the oil pipe 10 coupling 2 is connected to the upper joint 33 of the generator.

[0136] Figure 8 is a simplified structural diagram of the downhole lifting string provided by an embodiment of the present invention. As shown in Figure 8, in this embodiment, the downhole lifting energy storage string is divided into an inner string and an outer string. The inner string is composed of a sucker rod 1, an inner ring flow support 4 and a mover assembly 31; the stator assembly 32, energy storage body 6, load mechanism 5, generator upper joint 33, generator lower joint 34, generator energy storage joint 35 and electronic control body 7 of the downhole lifting energy storage string are the outer string. The outer string is connected to the oil pipe 10 and lowered into the designated formation. The heating assembly 51 is located at the waxing point of the oil well, and the signal receiver body is located below the dynamic liquid level. Then the sucker rod 1 with the mover assembly 31 is lowered. The mover assembly 31 is slightly longer than the generator stator to ensure that the downhole power generation link is always in working condition. As the sucker rod 1 reciprocates up and down, the downhole lift generator generates a certain amount of electrical energy due to the magnetic field and mechanical energy. Part of this energy is used to store energy in the energy storage assembly 64, and the other part is used for the electronic control of the lift generator. The energy generated by the lift generator is used for two functions: one part is used for high-power heating, which heats the oil flow lifted from the inner bore to a temperature above the wax precipitation point of the oil, thereby achieving the purpose of clearing and preventing wax from the entire tubing string; the other part is used to transmit and power downhole temperature and pressure signals. By measuring signals such as temperature and pressure below the dynamic liquid level, accurate downhole signals can be obtained, thereby adjusting the parameters of stroke and stroke frequency, realizing the intelligent construction of the oil production system.

[0137] Furthermore, the tubing string includes two-stage energy storage, a first-stage heating induction coil, and two-stage electromagnetic induction coils. A strong magnet (i.e., the mover assembly 31) is attached to the sucker rod 1, and a closed induction coil (i.e., the stator assembly 32) is designed on the oil pipe 10 section. The reciprocating motion of the sucker rod 1 generates an induced electromotive force, which charges the energy storage module, thereby fulfilling two functions: First, the energy storage discharge heats the oil pipe 10 and the oil flow through the oil pipe 10 at the waxing point, raising the temperature inside the oil pipe 10 and achieving a wax removal and prevention effect; second, the energy storage discharge powers the downhole temperature and pressure signal generator 52, which sends an acoustic wave signal from the sensor to the surface receiver. After encoding, decoding, and amplification, the temperature and pressure signal below the dynamic liquid level is obtained, allowing the stroke and frequency of the pumping unit system to be accurately adjusted, facilitating the intelligent construction of oilfield production systems. The tubing string consists of four parts, namely the inner tubing string: the first sucker rod 11, the second sucker rod 12, the mover assembly 31, the first sucker rod 11, the second sucker rod 12, the mover assembly 31; the outer tubing string: the insulated oil pipe, the ordinary oil pipe, the non-metallic oil pipe, the ordinary oil pipe, the non-metallic oil pipe, the ordinary oil pipe; between the oil casings: the stator assembly 32, the energy storage body 6, the signal generator 52; and the ground: the signal receiver.

[0138] A second aspect of this embodiment provides a downhole monitoring system, comprising a signal receiver, a monitoring sensor, and the downhole lifting energy storage string as described above;

[0139] The signal receiver is in communication with the signal transmitter 52 in the downhole lifting energy storage string;

[0140] The monitoring sensor is connected to the signal transmitter 52 and is used to provide a monitoring signal to the signal transmitter 52 .

[0141] In this embodiment, the monitoring sensor includes a temperature sensor and a pressure sensor.

[0142] In this embodiment, the monitoring sensor is connected to the energy storage body 6 of the downhole lifting energy storage string, and the energy storage body 6 provides electrical energy to the monitoring sensor.

[0143] A third aspect of this embodiment provides a downhole lifting and energy storage method, which is applied to the downhole lifting and energy storage string as described above, and includes:

[0144] The pumping rod 1 drives the movable subassembly 31 of the generator 3 to reciprocate to generate electrical energy;

[0145] The generated electrical energy is stored by the energy storage body 6 .

[0146] Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0147] Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if such changes and modifications fall within the scope of the claims and their equivalents, the present invention is intended to include such changes and modifications.

[0148] The above describes in detail the optional embodiments of the present invention in conjunction with the accompanying drawings. However, the embodiments of the present invention are not limited to the specific details in the above embodiments. Within the technical concept of the embodiments of the present invention, a variety of simple variations can be made to the technical solutions of the embodiments of the present invention, and these simple variations all fall within the scope of protection of the embodiments of the present invention. It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any appropriate manner without contradiction, and as long as the combination does not violate the concept of the embodiments of the present invention, it should also be regarded as the content disclosed in the embodiments of the present invention.

Claims

1. A downhole lifting energy storage string, characterized in that: include: A sucker rod, a power generation body and an energy storage body, wherein the power generation body includes a mover assembly and a stator assembly; The movable subassembly is fixedly sleeved on the sucker rod, the stator subassembly is sleeved outside the movable subassembly, and the length of the movable subassembly is greater than the length of the stator subassembly; The stator assembly is provided with a stator coil winding; The sucker rod can reciprocate in the pipe string, the mover assembly generates a radial magnetic field as the sucker rod reciprocates, and the stator coil winding of the stator assembly generates an induced current under the action of the radial magnetic field; The energy storage body is connected to the power generation body and is used to receive the induced current from the power generation body to obtain electric energy and store it; The sucker rod comprises a first sucker rod and a second sucker rod which are connected in sequence, the second sucker rod has a hollow oil passage, and the mover assembly is fixedly sleeved on the second sucker rod.

2. The downhole lifting energy storage string according to claim 1, characterized in that: The downhole lifting energy storage string further comprises: a load mechanism, The load mechanism is electrically connected to the energy storage body and is used to utilize the electrical energy of the energy storage body.

3. The downhole lifting energy storage string according to claim 2, characterized in that: The load mechanism is a heating component; The heating assembly is installed at the wax deposition point of the downhole lifting energy storage pipe string and is used for heating and removing wax.

4. The downhole lifting energy storage string according to claim 2, characterized in that: The load mechanism is a signal transmitter; The signal transmitter is communicatively connected with the signal receiver on the well and is used for transmitting the downhole test signal.

5. The downhole lifting energy storage string according to claim 1, characterized in that: The downhole lifting energy storage string also includes an inner ring flow support, which is fixedly installed on the sucker rod and is also fixedly connected to the mover assembly.

6. The downhole lifting energy storage string according to claim 1, characterized in that: The mover assembly comprises: a mover inner tube, a mover magnetic steel assembly, a mover retaining ring and a magnetic steel spacer ring; The inner tube of the mover is sleeved on the sucker rod and fixed to the inner ring flow support; The mover magnetic steel assembly is sleeved on the mover inner tube; The mover retaining ring is sleeved on the mover inner tube and arranged at the end of the mover inner tube, and is used to fix the mover magnetic steel assembly; The magnetic steel spacer ring is arranged between two adjacent mover magnetic steel assemblies.

7. The downhole lifting energy storage string according to claim 6, characterized in that: The mover magnetic steel assembly comprises: a magnetic steel and a magnetic steel protection ring; The magnetic steel sleeve is arranged on the inner tube of the mover; The magnetic steel protection ring is installed on the side of the magnetic steel away from the inner tube of the mover.

8. The downhole lifting energy storage string according to claim 1, characterized in that: The stator assembly comprises: a white steel liner, a stator coil winding and a stator retaining ring; The stator coil winding is wound on the white steel liner; The stator retaining ring is connected to the white steel liner, and the stator retaining ring is used to fix the stator coil winding.

9. The downhole lifting energy storage string according to claim 8, characterized in that: The stator coil winding comprises: a coil winding, an insulating sheet, a coil spacer ring and a silicon steel sheet; The coil spacer ring is attached to the white steel liner; The coil winding is wound on the coil spacer ring; The insulating sheets are arranged on both sides of the coil winding; A plurality of silicon steel sheets are overlapped and arranged between the insulating sheets of two adjacent coil windings.

10. The downhole lifting energy storage string according to claim 2, characterized in that: The generator also includes: an upper generator connector, a lower generator connector and a generator energy storage connector; The upper joint of the generator is sleeved outside the mover assembly and fixedly connected to the upper end of the stator assembly; The lower joint of the generator is sleeved outside the mover assembly and fixedly connected to the lower end of the stator assembly; The generator energy storage connector is connected to the generator lower connector.

11. The downhole lifting energy storage string according to claim 10, characterized in that: The energy storage body comprises an energy storage body joint, an energy storage body tube, an energy storage body tube, an energy storage body energy storage assembly and an energy storage body electric control joint; The energy storage body inner tube, the energy storage body outer tube, the energy storage body joint and the energy storage body electric control joint form an energy storage cavity, the energy storage body joint is installed at the upper end of the energy storage cavity and is respectively connected to the energy storage body inner tube and the energy storage body outer tube, the energy storage body electric control joint is installed at the lower end of the energy storage cavity and is respectively connected to the energy storage body inner tube and the energy storage body outer tube, and the energy storage body energy storage assembly is arranged in the energy storage cavity; The energy storage body connector is connected to the generator energy storage connector of the generator.

12. The downhole lifting energy storage string according to claim 11, characterized in that: The energy storage body also includes an energy storage body cable connector, and the energy storage body cable connector is installed on the energy storage body connector.

13. The downhole lifting energy storage string according to claim 11, characterized in that: The downhole lifting energy storage string also includes an electric control body, which includes an electric control outer tube, an electric control inner tube, an electric control component and an electric control load joint; The energy storage body electrically controlled connector, the electrically controlled outer tube, the electrically controlled inner tube and the electrically controlled load connector form an electrically controlled cavity. The energy storage body electrically controlled connector is installed at the upper end of the electrically controlled cavity and is respectively connected to the electrically controlled inner tube and the electrically controlled outer tube. The electrically controlled load connector is installed at the lower end of the electrically controlled cavity and is respectively connected to the electrically controlled inner tube and the electrically controlled outer tube. The electrically controlled component is placed in the electrically controlled cavity.

14. The downhole lifting energy storage string according to claim 13, characterized in that: The load mechanism comprises a load assembly, a load mechanism outer tube, a load mechanism inner tube and a lower joint; The electrically controlled load connector, the load mechanism inner tube, the load mechanism outer tube and the lower connector form a load cavity; the load assembly is mounted on the upper end of the load cavity and is respectively connected to the load mechanism inner tube and the load mechanism outer tube; the lower connector is mounted on the lower end of the load cavity and is respectively connected to the load mechanism inner tube and the load mechanism outer tube; the load assembly is placed in the load cavity.

15. The downhole lifting energy storage string according to claim 10, characterized in that: The downhole lifting energy storage pipe string also includes an oil pipe coupling, and the lower end of the oil pipe coupling is connected to the upper joint of the generator.

16. A downhole monitoring system, characterized in that: It comprises a signal receiver, a monitoring sensor and a downhole lifting energy storage string as claimed in any one of claims 1 to 15; The signal receiver is communicatively connected with the signal transmitter in the downhole lifting energy storage string; The monitoring sensor is connected to the signal transmitter and is used to provide a monitoring signal to the signal transmitter.

17. The downhole monitoring system according to claim 16, characterized in that: The monitoring sensor includes a temperature sensor and a pressure sensor.

18. The downhole monitoring system according to claim 17, characterized in that: The monitoring sensor is connected to the energy storage body of the downhole lifting energy storage pipe string, and the energy storage body provides electrical energy to the monitoring sensor.

19. A method for underground lifting and energy storage, characterized in that: The method is applied to the downhole lifting energy storage string according to any one of claims 1 to 15, and the method comprises: The pumping rod drives the moving element of the generator to reciprocate to generate electrical energy; The generated electrical energy is stored by an energy storage body.

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