An electric pulse oil downhole unblocking system and method

Abstract

The application relates to an electric pulse oil downhole unblocking system and method, and relates to the technical field of electric pulse unblocking, and the electric pulse oil downhole unblocking method comprises the following steps: connecting to commercial power, a second power distributor supplies power to a first power distributor according to preset electric energy output parameters; the first power distributor supplies power to an energy storage unit through a high-voltage power supply; a control unit collects and analyzes downhole temperature, downhole pressure and current peak values through a measuring unit; according to the data analysis result, the control unit sends preset pulse signals to the energy storage unit, triggers an electronic switch to release high-voltage pulses; the control unit controls a wire feeding mechanism to feed a metal wire to both ends of a discharge electrode, the high-voltage pulses generate discharge between the discharge electrodes through the metal wire, impact waves are formed to break the blockage, electric pulses are discharged through the oil mixture, the liquid is gasified and expanded in a time of several microseconds, a pressure wave is generated to strip mineral matter blocked in a pipeline pore, and oil smoothly enters the oil well, thereby improving the oil well yield.

Description

Technical Field

[0001] This invention relates to the field of electrical pulse unclogging technology, and in particular to an electrical pulse downhole unclogging system and method for oil wells. Background Technology

[0002] During oil extraction, a mixture of groundwater, oil, and various minerals flows into the well through the pores of the well pipes. The oil is then pumped to the surface by a pumping unit. However, the composition of underground minerals is complex, and a large amount of substances adhere to the permeable pores of the pipes during the extraction process. Over time, this causes the pores to become smaller or even blocked, reducing oil well production or even preventing normal production.

[0003] There are generally two methods for unblocking oil wells: physical and chemical. Traditional physical unblocking involves extracting the blocked pipe from the well, cleaning it on the surface, and then lowering it back into the well. This process is time-consuming, costly, and causes prolonged downtime, impacting production capacity. Chemical unblocking involves introducing chemicals into the well, using a chemical reaction to decompose the blockage and thus unblock the well. However, this method is costly, has a short effective period, and can cause secondary damage to the well and environmental pollution.

[0004] Application number CN201811523040.9 discloses an electric pulse oil well downhole unclogging system, comprising a DC high-voltage power supply, a cable retractor, a cable, a control unit, and a generator. The DC high-voltage power supply is used to boost the voltage of the input DC high-voltage power supply. The cable retractor is used to accommodate and retract the cable, with one end of the cable connected to the cable retractor and the other end extending out of the cable retractor and connected to the generator. The control unit is used to control the DC high-voltage power supply, the cable retractor, and the generator. The generator includes an energy storage unit, a solid-state discharge switch, and discharge electrodes. The upper end of the energy storage unit is connected to the other end of the cable, and the energy storage unit is used to store the electrical energy transmitted by the cable. The energy storage unit includes a capacitor. The solid-state discharge switch is used to control the discharge of the storage unit. The discharge electrodes are used to release the electrical energy stored in the energy storage unit to generate a shock wave. The above invention utilizes the strong shock wave generated by the electric pulse high-voltage discharge to unclogging pipe pores, with high working efficiency, simple operation, and significantly reduced unclogging costs.

[0005] The existing technical solutions mentioned above have the following drawbacks: 1. Physical unblocking requires a long cycle and is costly; 2. Chemical unblocking is costly and has a short effective period. Summary of the Invention

[0006] To address the shortcomings of existing technologies, the objective of this invention is achieved through the following technical solution:

[0007] An electrical pulse downhole well unclogging system; comprising:

[0008] The logging cable vehicle and the derrick, wherein the logging cable vehicle includes a second signal amplifier and a second power distributor;

[0009] The downhole equipment includes a control unit, an energy storage unit, an electronic switch, a wire feeding mechanism, a first signal amplifier, and a first power distributor; the downhole equipment employs a pulse generator.

[0010] The power input terminal of the second power distributor is connected to the mains power; the first power output terminal of the second power distributor is connected to the power input terminal of the first power distributor; the first signal transmission terminal of the second signal amplifier is connected to the first signal transmission terminal of the first signal amplifier.

[0011] The first signal amplifier and the second signal amplifier transmit communication signals via the 485 communication protocol;

[0012] The first power output terminal of the first power distributor is connected to the power input terminal of the first signal amplifier; the second power output terminal of the first power distributor is connected to the power input terminal of the control unit.

[0013] The first signal control terminal of the control unit is connected to the second signal transmission terminal of the first signal amplifier;

[0014] The second signal control terminal of the control unit is connected to the signal receiving terminal of the energy storage unit; the third signal control terminal of the control unit is connected to the signal receiving terminal of the electronic switch; the fourth signal control terminal of the control unit is connected to the signal receiving terminal of the wire feeding mechanism; the power output terminal of the energy storage unit is connected to the power input terminal of the electronic switch; the energy storage unit is provided with a discharge electrode; the discharge electrode is a transverse electrode.

[0015] The downhole equipment also includes a measurement unit and a high-voltage power supply; wherein...

[0016] The power input terminal of the measuring unit is connected to the third power output terminal of the first power distributor; the power input terminal of the high-voltage power supply is connected to the fourth power output terminal of the first power distributor to complete the power supply for each unit of the downhole equipment.

[0017] The signal output terminal of the measurement unit is connected to the fifth signal control terminal of the control unit;

[0018] The sixth signal control terminal of the control unit is connected to the signal receiving terminal of the high-voltage power supply; the power output terminal of the high-voltage power supply is connected to the power input terminal of the energy storage unit.

[0019] By adopting the above technical solution, the wellhead equipment consists of a logging cable trolley (including cable winch, data display terminal, second power distributor and second signal amplifier) ​​and a derrick. It is responsible for connecting to the mains power, supplying power to the downhole equipment through the cable, and using the winch and derrick to realize the lifting and lowering control of the downhole equipment.

[0020] The core of the downhole equipment is the pulse generator, which includes a high-voltage power supply, an energy storage unit (capacitor), an electronic switch, a discharge electrode, and a control unit. The workflow is as follows: Power from the surface is transmitted via cable to the first downhole power distributor, supplying power to each unit; the high-voltage power supply stores electrical energy in the capacitor; the control unit triggers the electronic switch based on feedback from the measurement unit (such as the location of a blockage), causing the energy storage unit to discharge instantaneously, generating an electrical pulse shock wave at the discharge electrode to efficiently clear blockages in the pores; the downhole pulse generator generates a high-intensity pressure wave to peel away blockages in the well's pipeline pores, improving oil flowability.

[0021] The present invention is further configured such that: the measuring unit includes a temperature sensor, a pressure sensor and a current sensor; the temperature sensor collects the downhole temperature, the current sensor collects the peak current, and the pressure sensor collects the downhole pressure and the burst pressure.

[0022] By adopting the above technical solution and integrating temperature, pressure, and current sensors into the measurement unit, accurate monitoring and real-time feedback of the downhole environment and equipment operating status are achieved. By collecting downhole temperature, pressure, and current peak data in real time, the system can dynamically adjust the intensity and frequency of electrical pulses to ensure efficient unblocking and avoid excessive energy consumption. The collaborative work of multiple sensors provides comprehensive data support for the control unit, improving the accuracy and reliability of unblocking operations and reducing environmental interference.

[0023] The present invention is further configured such that: the logging cable trolley also includes a cable reel and a data display terminal; wherein, the second power output terminal of the second power distributor is connected to the power input terminal of the data display terminal; the third power output terminal of the second power distributor is connected to the power input terminal of the cable reel; and the fourth power output terminal of the second power distributor is connected to the power input terminal of the second signal amplifier.

[0024] The second signal transmission terminal of the second signal amplifier is connected to the signal receiving terminal of the data display terminal.

[0025] By adopting the above technical solution, the cable reel integrates the power generation unit and the charging unit to form a self-sufficient energy closed loop, driving the intelligent winding and unwinding of the cable and ensuring continuous power supply to the downhole equipment. Combined with 485 communication, it realizes two-way monitoring between the well and the well. Its advantages are to improve the energy autonomy and system reliability of remote oil well operations and ensure uninterrupted and efficient operation of the shock wave clearing process.

[0026] Secondly, the present invention also provides an electrical pulse method for unclogging oil wells, employing the following technical solution:

[0027] A method for unclogging downhole oil wells using electrical pulses, applied to the aforementioned electrical pulse downhole oil well unclogging system, includes:

[0028] The surface equipment is connected to the mains power, and the second power distributor supplies power to the first power distributor of the downhole equipment according to the preset power output parameters.

[0029] The first power distributor supplies power to the energy storage unit via a high-voltage power supply, and the control unit collects and analyzes downhole temperature, downhole pressure and current peak through the measurement unit;

[0030] Based on the data analysis results, the control unit sends a preset pulse signal to the energy storage unit through the DSP controller, triggering the electronic switch to release the high-voltage pulse;

[0031] The control unit controls the wire feeding mechanism to feed the metal wire to both ends of the discharge electrode. The high voltage pulse generates a discharge between the discharge electrodes through the metal wire, forming a shock wave to break up the blockage in the well.

[0032] The control unit detects the breaking pressure of the shock wave on the downhole blockage through the measuring unit, and obtains the blasting pressure;

[0033] The control unit uses an adaptive control algorithm to correct the blasting pressure based on downhole temperature, downhole pressure, and peak current.

[0034] All data is amplified by the first and second signal amplifiers and transmitted to the data display terminal of the surface equipment. After the discharge is completed, the high-voltage power supply of the control unit charges the energy storage unit to provide energy for the next round of pulse discharge until all the blockages in the well are broken.

[0035] By adopting the above technical solution, the equipment above ground is connected to the mains power supply, and the power is supplied to the first power distributor below ground via the second power distributor. The high-voltage power supply charges the energy storage unit (capacitor), while the control unit collects downhole temperature, pressure, and current peak data in real time through the measurement unit. After analyzing the data, the control unit (including the DSP controller) triggers the electronic switch according to preset parameters to release the high-voltage electrical energy of the energy storage unit to the discharge electrode. The wire feeding mechanism is synchronously controlled to send the metal wire to both ends of the transverse electrode. The high-voltage pulse breaks down the metal wire to generate a hydroelectric effect, forming a high-intensity shock wave that breaks up the blockage. The measurement unit detects the shock wave blast pressure, and all data are amplified by the above-ground and downhole signal amplifiers and transmitted to the display terminal above ground. After discharge, the high-voltage power supply automatically charges the energy storage unit, and the above process is repeated until the blockage is cleared. The transverse electrode, combined with the metal wire discharge mechanism, focuses the shock wave energy, improving the accuracy and range of pore clearing. Real-time feedback of multiple parameters (temperature / pressure / peak current / blast pressure) drives the DSP to dynamically adjust the pulse parameters, avoiding ineffective energy consumption and equipment damage.

[0036] A further provision of the present invention is that the control unit uses an adaptive control algorithm to correct the burst pressure based on downhole temperature, downhole pressure, and peak current. The specific steps are as follows:

[0037] The adaptive control algorithm determines whether the downhole temperature and downhole pressure received in the control unit exceed the data limits.

[0038] If both the downhole temperature and the downhole pressure are within the corresponding preset data limit range, the current data is determined to be valid, and the pressure difference between two adjacent burst pressures is calculated, and then compared with the preset pressure difference threshold to determine a sudden change anomaly.

[0039] If the pressure difference is less than the pressure difference threshold, the current burst pressure is determined to be normal, and the correlation between the current peak value and the burst pressure is determined.

[0040] If the peak current is positively correlated with the blasting pressure, the correlation logic between the current data is determined to be normal, and the downhole temperature and the blasting pressure are fitted and determined.

[0041] If the downhole temperature continues to increase but the burst pressure does not reach the lower limit of the preset burst pressure range, it is determined that the electrohydraulic effect is attenuating, and the control unit controls the wire feeding mechanism to replace the metal wire after every N discharges.

[0042] If the downhole temperature does not reach the lower limit of the preset temperature range but the blasting pressure is greater than the upper limit of the blasting pressure range, then the energy storage unit is determined to have excess energy, and the control unit increases the discharge interval of the discharge electrode to M times.

[0043] The consistency between the peak current and the burst pressure is verified.

[0044] If the peak current is within a preset current threshold range but the burst pressure is less than the lower limit of the burst pressure range, then the shock wave is determined to be deviated, and the control unit controls the transverse electrode to discharge alternately and / or increases the number of pulses to K times the preset number limit value.

[0045] By adopting the above technical solution, and by verifying downhole temperature, pressure and current peak data in real time, abnormal working conditions such as hydraulic-electric effect attenuation, energy excess or shock wave deviation are intelligently determined. The replacement frequency of metal wire, discharge interval and pulse strategy are dynamically adjusted to achieve precise adaptive control of blasting pressure. Based on the integration of multiple logic judgments and closed-loop feedback, the safety and efficiency of downhole operations are significantly improved.

[0046] In summary, the beneficial technical effects of the present invention are as follows:

[0047] 1. High-power electric pulses and discharge plasma convert electrical and chemical energy into shock wave mechanical energy. By repeatedly operating the pulse power source, controllable, repetitive, strong shock waves are generated. When a high-voltage electric pulse discharges through a petroleum mixture, the liquid vaporizes and expands within microseconds, producing an explosive effect. The intense pressure wave can strip away minerals blocking the pores of the pipeline, allowing oil to smoothly enter the oil well and increasing oil production.

[0048] 2. The transverse electrode combined with the metal wire discharge mechanism focuses the shock wave energy, improving the accuracy and range of pore unblocking;

[0049] 3. By verifying downhole temperature, pressure and current peak data in real time, the system can intelligently determine abnormal conditions such as hydroelectric effect attenuation, excess energy or shock wave deviation, and dynamically adjust the wire replacement frequency, discharge interval and pulse strategy to achieve precise adaptive control of the burst pressure. Based on the integration of multiple logic judgments and closed-loop feedback, the system can significantly improve the safety and efficiency of downhole operations. Attached Figure Description

[0050] Figure 1 This is a schematic diagram of the structure of an electric pulse oil well unclogging system according to one embodiment of the present invention.

[0051] Figure 2 This is a schematic diagram of the structure of an electric pulse oil well unclogging system according to one embodiment of the present invention.

[0052] Figure 3 This is a schematic diagram of the structure of an electric pulse oil well unclogging system according to one embodiment of the present invention.

[0053] Figure 4 This is a schematic diagram of the process of an electric pulse oil well unclogging method according to one embodiment of the present invention. Detailed Implementation

[0054] The present invention will be further described in detail below with reference to the accompanying drawings.

[0055] Example 1:

[0056] Reference Figures 1-3 The present invention discloses an electrical pulse downhole oil well unclogging system, comprising:

[0057] The logging cable vehicle and the derrick, wherein the logging cable vehicle includes a second signal amplifier and a second power distributor;

[0058] The downhole equipment includes a control unit, an energy storage unit, an electronic switch, a wire feeding mechanism, a first signal amplifier, and a first power distributor; the downhole equipment employs a pulse generator.

[0059] The power input terminal of the second power distributor is connected to the mains power; the first power output terminal of the second power distributor is connected to the power input terminal of the first power distributor; the first signal transmission terminal of the second signal amplifier is connected to the first signal transmission terminal of the first signal amplifier.

[0060] The first signal amplifier and the second signal amplifier transmit communication signals via the 485 communication protocol;

[0061] The first power output terminal of the first power distributor is connected to the power input terminal of the first signal amplifier; the second power output terminal of the first power distributor is connected to the power input terminal of the control unit.

[0062] The first signal control terminal of the control unit is connected to the second signal transmission terminal of the first signal amplifier;

[0063] The second signal control terminal of the control unit is connected to the signal receiving terminal of the energy storage unit; the third signal control terminal of the control unit is connected to the signal receiving terminal of the electronic switch; the fourth signal control terminal of the control unit is connected to the signal receiving terminal of the wire feeding mechanism; the power output terminal of the energy storage unit is connected to the power input terminal of the electronic switch; the energy storage unit is provided with a discharge electrode; the discharge electrode is a transverse electrode.

[0064] The downhole equipment also includes a measurement unit and a high-voltage power supply; wherein...

[0065] The power input terminal of the measuring unit is connected to the third power output terminal of the first power distributor; the power input terminal of the high-voltage power supply is connected to the fourth power output terminal of the first power distributor to complete the power supply for each unit of the downhole equipment.

[0066] The signal output terminal of the measurement unit is connected to the fifth signal control terminal of the control unit;

[0067] The sixth signal control terminal of the control unit is connected to the signal receiving terminal of the high-voltage power supply; the power output terminal of the high-voltage power supply is connected to the power input terminal of the energy storage unit.

[0068] In this embodiment, the control unit uses a touch screen + PLC control system to control the charging unit, cable storage device, downhole energy storage unit and discharge switch. It has built-in multiple safety protection functions such as overcurrent, overvoltage, and leakage to prevent safety accidents caused by high voltage leakage due to cable damage during operation.

[0069] Energy storage unit: mainly uses coaxial capacitors, the size of which is customized according to the structural dimensions of the energy storage unit. Taking advantage of its coaxial output characteristics, the inductance is extremely small, which can achieve an output waveform with characteristics such as large discharge current and steep rise time.

[0070] Measurement Unit: The unit uses components such as pressure sensors to measure and collect experimental data such as the pressure shock wave generated by the blast, the number of charge and discharge cycles, and the charging voltage, and transmits the data to the data display terminal through the logging cable.

[0071] Electronic switch: The discharge is triggered by a solid-state electronic switch, which has stable switching characteristics, can adapt to different working environments, and can withstand temperatures up to 100 degrees Celsius. The discharge frequency is once every 10 seconds.

[0072] Discharge electrode: The discharge electrode adopts a non-traditional horizontal electrode design. Compared with the traditional vertical electrode, the horizontal electrode has the advantages of controllable blasting direction and concentrated energy. The control unit realizes the shock wave to drive the electrode structure to rotate, thereby realizing pulse impact on the entire well wall.

[0073] Wire feeding mechanism: It adopts servo motor and single-chip microcomputer control to realize automatic wire feeding function downhole, and uses electronic switch frequency to repeatedly discharge, and can ensure that the metal wire is not affected by shock wave.

[0074] The implementation principle of this embodiment is as follows: the surface equipment converts mains power into adaptive power via a logging cable trolley, and transmits it to the downhole pulse generator via cable; the power distributor in the downhole equipment distributes power to drive the operation of each unit; the control unit transmits downhole temperature, pressure, and discharge current data collected by the measurement unit bidirectionally via the 485 communication protocol. The charging parameters of the energy storage unit are dynamically adjusted by the high-voltage power supply. The high-voltage pulse is triggered by the electronic switch to vaporize the metal wire between the electrodes instantly, generating a high-intensity shock wave to remove the blockage in the pipeline. At the same time, the wire feeding mechanism ensures a continuous supply of electrode materials. The well data display terminal monitors the operation status in real time, forming a closed-loop unblocking system of "power supply - data acquisition - adaptive control - pulse generation - status feedback" to achieve efficient unblocking of oil channels.

[0075] Example 2:

[0076] The measurement unit includes a temperature sensor, a pressure sensor, and a current sensor; the temperature sensor collects the downhole temperature, the current sensor collects the peak current, and the pressure sensor collects the downhole pressure and the burst pressure.

[0077] The implementation principle of this embodiment is as follows: After the power from the well site is converted by the second power distributor in the logging cable vehicle, it is transmitted to the first power distributor of the downhole equipment through the cable, driving the temperature, pressure and current sensors to collect downhole temperature, burst pressure and current peak value in real time; the downhole control unit dynamically analyzes the temperature-pressure coupling effect and current-pressure consistency, and adjusts the charging parameters of the high-voltage power supply to the energy storage unit accordingly.

[0078] Example 3:

[0079] The cable reel includes a cable storage device, a charging unit, a built-in controller, and a power generation unit; wherein...

[0080] The first power output terminal of the power generation unit is connected to the power input terminal of the charging unit; the first power output terminal of the power generation unit is connected to the power input terminal of the built-in controller.

[0081] The first signal control terminal of the built-in controller is connected to the signal transmission terminal of the cable storage device; the second signal control terminal of the built-in controller is connected to the signal transmission terminal of the charging unit.

[0082] The power output terminal of the charging unit is connected to the power input terminal of the cable storage device.

[0083] The implementation principle of this embodiment is as follows: The power generation unit (such as a wind-solar hybrid system) of the cable reel generates electrical energy, which is preferentially supplied to the charging unit (lithium battery pack) and the built-in controller. The built-in controller dynamically adjusts the power supply intensity of the charging unit to the motor of the cable reeling device by real-time monitoring of cable tension and downhole equipment power consumption, so as to realize intelligent cable reeling and unloading. At the same time, the charging unit stores excess energy and provides reverse power supply to ensure continuous operation when power generation is insufficient. The electrical energy output by the power generation unit is also supplied to the downhole equipment through the cable to drive the pulse generator. The built-in controller communicates bidirectionally with the surface data display terminal and the downhole control unit through the 485 protocol to synchronously transmit cable status, energy storage capacity and unblocking operation data, forming a five-in-one self-sustaining energy management and operation system of "power generation → energy storage → cable control → power supply → communication", which ensures efficient unblocking operation of oil wells in areas without mains power.

[0084] Example 4:

[0085] Reference Figure 4An electric pulse oil well unblocking method, applied to the electric pulse oil well unblocking system, includes: the wellhead equipment is connected to the mains power, and a second power distributor supplies power to the first power distributor of the wellhead equipment according to preset power output parameters;

[0086] The first power distributor supplies power to the energy storage unit via a high-voltage power supply, and the control unit collects and analyzes downhole temperature, downhole pressure and current peak through the measurement unit;

[0087] Based on the data analysis results, the control unit sends a preset pulse signal to the energy storage unit through the DSP controller, triggering the electronic switch to release the high-voltage pulse;

[0088] The control unit controls the wire feeding mechanism to feed the metal wire to both ends of the discharge electrode. The high voltage pulse generates a discharge between the discharge electrodes through the metal wire, forming a shock wave to break up the blockage in the well.

[0089] The control unit detects the breaking pressure of the shock wave on the downhole blockage through the measuring unit, and obtains the blasting pressure;

[0090] The control unit uses an adaptive control algorithm to correct the blasting pressure based on downhole temperature, downhole pressure, and peak current. All data is amplified by the first and second signal amplifiers and transmitted to the data display terminal of the surface equipment. After the discharge is completed, the high-voltage power supply charges the energy storage unit to provide energy for the next round of pulse discharge until all the downhole blockage is broken.

[0091] The implementation principle of this embodiment is as follows: the surface power in the well is converted into electrical energy with preset parameters by the second power distributor, and then transmitted to the first power distributor downhole via cable to drive the high-voltage power supply to charge the energy storage unit; the control unit dynamically corrects the target value of the burst pressure through an adaptive algorithm based on the downhole temperature, pressure and current peak data collected by the measurement unit, and the DSP controller generates a customized pulse signal to trigger the electronic switch to release the high-voltage pulse; at the same time, the wire feeding mechanism delivers a metal wire to the transverse electrode, and the pulse current causes the metal wire to vaporize instantaneously, generating a high-intensity shock wave to break the blockage; the burst pressure data and correction results detected in real time are transmitted to the surface data display terminal via the 485 communication protocol (with the first / second signal amplifier working together); after a single discharge is completed, the high-voltage power supply automatically replenishes the energy storage unit, and the closed-loop process of "data acquisition → adaptive correction → pulse discharge → effect feedback" is executed cyclically until the downhole blockage is completely cleared, and the oil channel is efficiently unblocked.

[0092] Example 5:

[0093] The specific steps of the control unit in using an adaptive control algorithm to correct the burst pressure based on downhole temperature, downhole pressure, and peak current are as follows:

[0094] The adaptive control algorithm determines whether the downhole temperature and downhole pressure received in the control unit exceed the data limits.

[0095] If both the downhole temperature and the downhole pressure are within the corresponding preset data limit range, the current data is determined to be valid, and the pressure difference between two adjacent burst pressures is calculated and compared with the preset pressure difference threshold to determine a sudden change anomaly; otherwise, the current data is determined to be invalid and is discarded.

[0096] If the pressure difference is less than the pressure difference threshold, the current burst pressure is determined to be normal, and the correlation between the current peak value and the burst pressure is determined; otherwise, the current burst pressure is determined to be abnormal, and the measurement unit performs a self-check.

[0097] If the peak current is positively correlated with the blasting pressure, the correlation logic between the current data is determined to be normal, and the downhole temperature and the blasting pressure are fitted and determined; otherwise, the correlation logic between the current data is determined to be abnormal, and the measurement unit performs a self-check.

[0098] If the downhole temperature continues to increase but the burst pressure does not reach the lower limit of the preset burst pressure range, it is determined that the electrohydraulic effect is attenuating, and the control unit controls the wire feeding mechanism to replace the metal wire after every N discharges.

[0099] If the downhole temperature does not reach the lower limit of the preset temperature range but the blasting pressure is greater than the upper limit of the blasting pressure range, then the energy storage unit is determined to have excess energy, and the control unit increases the discharge interval of the discharge electrode to M times.

[0100] The consistency between the peak current and the burst pressure is verified.

[0101] If the peak current is within a preset current threshold range but the burst pressure is less than the lower limit of the burst pressure range, then the shock wave is determined to be deviated, and the control unit controls the transverse electrode to discharge alternately and / or increases the number of pulses to K times the preset number limit value.

[0102] In this embodiment, based on the thermal conductivity of water being 0.6 W / mk, the temperature conducted is inversely proportional to the distance and directly proportional to the time.

[0103] q = -λA(dt / dx)

[0104] Where λ is the thermal conductivity, A is the heat transfer area, t is the temperature, x is the coordinate on the heat transfer surface, q is the heat flux density transferred along the x direction (in terms of heat transfer per unit time), and dt / dx is the rate of temperature change of the object along the x direction (proportional to the temperature difference and inversely proportional to the length).

[0105] Because the discharge time is short, about 50 μs, the heat transfer speed is slow and mainly concentrated near the arc. Assuming that the arc is point-shaped, the heat will be conducted outward in a spherical shape. According to the temperature transfer of 60% per meter per second, the heat conduction range per second is 1 / (1-0.6) = 2.5 meters. In the actual 50 μs, the heat conduction radius is about 1.2*10-4 meters, or 120 μm.

[0106] The system stores approximately 1.5 kJ of energy. The thermal volume of water is approximately 4200 J / kg°C. Assuming the water temperature is 20°C, 1500 J of energy can vaporize 4 g of water. When this energy is confined within a radius of 0.24 mm, the temperature will rise to...

[0107] Δt=Q / CM=1500J / (4200*0.14*10-3kg)=2400℃. Based on the empirical formula for the expansion pressure of steam after heating, P=760exp[9(1-(375.15 / T)^1.37)]mmhg=949kmmhg, approximately 130MPa. That is, if the electric arc breaks down and discharges, a pulse pressure of 130MPa can theoretically be generated. This is sufficient to clear blockages in the pipe.

[0108] The implementation principle of this embodiment is as follows: By real-time verification of downhole temperature, pressure, and current peak data (triple judgment: data exceeding limits → pressure sudden change → current correlation), abnormal working conditions such as hydroelectric effect attenuation, energy excess, or shock wave deviation are intelligently identified; based on adaptive algorithm dynamic decision-making: at high temperature and low pressure, the metal wire is replaced every N discharges to compensate for energy; at low temperature and high pressure, the discharge interval is extended by M times to prevent overload; when the current meets the standard but the pressure is insufficient, the electrode is activated to alternately discharge and the number of pulses is multiplied (K times) to focus energy; a closed-loop control of "data acquisition → anomaly diagnosis → parameter self-adjustment → shock wave generation → effect feedback" is formed, which efficiently removes blockages while ensuring downhole safety.

[0109] When the temperature of the heavy oil well rises to 150℃ (exceeding the preset lower limit of 120℃), and the burst pressure remains below the standard value by 15%, the temperature / pressure ratio is within the effective range, the pressure difference between adjacent pressures is less than the threshold, and the current is positively correlated with the pressure. If the temperature continues to rise but the pressure does not reach the lower limit, it is determined that the electrohydraulic effect is decaying. Therefore, the metal wire is automatically replaced every 5 discharges (N=5) to prevent electrode oxidation and to increase the charging voltage by 8% to compensate for energy loss. Finally, the burst pressure returns to the standard range, and the unclogging efficiency is improved by 40%.

[0110] When a hard calcium scale layer causes shock wave scattering, and the peak current reaches the standard (25kA) but the burst pressure is only 60% of the expected value, the current is within the threshold range but the pressure is insufficient → shock wave deviation is determined; the control unit activates the lateral electrode alternating discharge mode to concentrate energy in the target area; and increases the number of pulses to twice the standard value (K=2) to compensate for single-shot efficiency; abnormal current fluctuations are found through correlation verification, so the electrode spacing fine adjustment (+3mm) is activated simultaneously; finally, the crushing efficiency reaches the standard after the shock wave is focused, avoiding 12 ineffective discharges and saving 30% energy.

[0111] The embodiments described herein are preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Therefore, all equivalent changes made in accordance with the structure, shape, and principle of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A method for unclogging oil wells using electrical pulses, applied to an electrical pulse oil well unclogging system, the system comprising a logging cable trolley and a derrick, the logging cable trolley comprising a second signal amplifier and a second power distributor; the downhole equipment comprising a control unit, an energy storage unit, an electronic switch, a wire feeding mechanism, a first signal amplifier, and a first power distributor; the downhole equipment employing a pulse generator; the power input terminal of the second power distributor is connected to mains power; the first power output terminal of the second power distributor is connected to the power input terminal of the first power distributor; the first signal transmission terminal of the second signal amplifier is connected to the first signal transmission terminal of the first signal amplifier; the first power output terminal of the first power distributor is connected to the power input terminal of the first signal amplifier; the second power output terminal of the first power distributor is connected to the power input terminal of the control unit; the first signal control terminal of the control unit is connected to the second signal transmission terminal of the first signal amplifier; The second signal control terminal of the control unit is connected to the signal receiving terminal of the energy storage unit; the third signal control terminal of the control unit is connected to the signal receiving terminal of the electronic switch; the fourth signal control terminal of the control unit is connected to the signal receiving terminal of the wire feeding mechanism; the power output terminal of the energy storage unit is connected to the power input terminal of the electronic switch; the energy storage unit is provided with a discharge electrode; the discharge electrode is a transverse electrode. Its features are: The control unit employs an adaptive control algorithm to correct the burst pressure based on downhole temperature, downhole pressure, and peak current. The specific steps are as follows: The adaptive control algorithm determines whether the downhole temperature and downhole pressure received in the control unit exceed the data limits. If both the downhole temperature and the downhole pressure are within the corresponding preset data limit range, the current data is determined to be valid, and the pressure difference between two adjacent burst pressures is calculated, and then compared with the preset pressure difference threshold to determine a sudden change anomaly. If the pressure difference is less than the pressure difference threshold, the current burst pressure is determined to be normal, and the correlation between the current peak value and the burst pressure is determined. If the peak current is positively correlated with the blasting pressure, the correlation logic between the current data is determined to be normal, and the downhole temperature and the blasting pressure are fitted and determined. If the downhole temperature continues to increase but the burst pressure does not reach the lower limit of the preset burst pressure range, it is determined that the electrohydraulic effect is attenuating, and the control unit controls the wire feeding mechanism to replace the metal wire after every N discharges. If the downhole temperature does not reach the lower limit of the preset temperature range but the burst pressure is greater than the upper limit of the burst pressure range, then the energy storage unit is determined to have excess energy, and the control unit increases the discharge interval of the discharge electrode to M times; the consistency between the peak current and the burst pressure is verified. If the peak current is within a preset current threshold range but the burst pressure is less than the lower limit of the burst pressure range, then the shock wave is determined to be deviated, and the control unit controls the transverse electrode to discharge alternately and / or increases the number of pulses to K times the preset number limit value.

2. The method for unclogging oil wells using electrical pulses according to claim 1, characterized in that, The downhole equipment also includes a measurement unit and a high-voltage power supply; wherein, the power input terminal of the measurement unit is connected to the third power output terminal of the first power distributor; the power input terminal of the high-voltage power supply is connected to the fourth power output terminal of the first power distributor to complete the power supply for each unit of the downhole equipment; the signal output terminal of the measurement unit is connected to the fifth signal control terminal of the control unit; the sixth signal control terminal of the control unit is connected to the signal receiving terminal of the high-voltage power supply; and the power output terminal of the high-voltage power supply is connected to the power input terminal of the energy storage unit.

3. The method for unclogging oil wells using electrical pulses according to claim 2, characterized in that, The measurement unit includes a temperature sensor, a pressure sensor, and a current sensor; the temperature sensor collects the downhole temperature, the current sensor collects the peak current, and the pressure sensor collects the downhole pressure and the burst pressure.

4. The method for unclogging oil wells using electrical pulses according to claim 1, characterized in that, The first signal amplifier and the second signal amplifier transmit communication signals via the 485 communication protocol.

5. The method for unclogging downhole oil wells using electrical pulses according to claim 1, characterized in that, The logging cable trolley also includes a cable reel and a data display terminal; wherein, the second power output terminal of the second power distributor is connected to the power input terminal of the data display terminal; the third power output terminal of the second power distributor is connected to the power input terminal of the cable reel; the fourth power output terminal of the second power distributor is connected to the power input terminal of the second signal amplifier; and the second signal transmission terminal of the second signal amplifier is connected to the signal receiving terminal of the data display terminal.

6. The method for unclogging downhole oil wells using electrical pulses according to claim 5, characterized in that, The cable reel includes a cable storage device, a charging unit, a built-in controller, and a power generation unit; wherein, the first power output terminal of the power generation unit is connected to the power input terminal of the charging unit; the first power output terminal of the power generation unit is connected to the power input terminal of the built-in controller; the first signal control terminal of the built-in controller is connected to the signal transmission terminal of the cable storage device; the second signal control terminal of the built-in controller is connected to the signal transmission terminal of the charging unit; and the power output terminal of the charging unit is connected to the power input terminal of the cable storage device.

7. The method for unclogging oil wells using electrical pulses according to claim 1, characterized in that, The method for unclogging oil wells also includes: The surface equipment is connected to the mains power, and the second power distributor supplies power to the first power distributor of the downhole equipment according to the preset power output parameters. The first power distributor supplies power to the energy storage unit via a high-voltage power supply, and the control unit collects and analyzes downhole temperature, downhole pressure and current peak through the measurement unit; Based on the data analysis results, the control unit sends a preset pulse signal to the energy storage unit through the DSP controller, triggering the electronic switch to release the high-voltage pulse; The control unit controls the wire feeding mechanism to deliver the metal wire to both ends of the discharge electrode. The high-voltage pulse generates a discharge between the discharge electrodes through the metal wire, forming a shock wave that breaks up the blockage in the well.

8. The method for unclogging downhole oil wells using electrical pulses according to claim 7, characterized in that, The method for unclogging oil wells also includes: The control unit detects the breaking pressure of the shock wave on the downhole blockage through the measuring unit, and obtains the blasting pressure; The control unit uses an adaptive control algorithm to correct the blasting pressure based on downhole temperature, downhole pressure, and peak current. All data is amplified by the first and second signal amplifiers and then transmitted to the data display terminal of the well equipment. After the discharge is completed, the high-voltage power supply charges the energy storage unit to provide energy for the next round of pulse discharge until all the blockages in the well are broken.

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