A digital power supply system of a welding machine special for welding in a wellbore

Abstract

The application relates to the oil field field, in particular to a digital power supply system of a welding machine special for in-well welding, which comprises a downhole welding protection system, a main control signal integrated system and a signal output integrated system installed in the downhole welding protection system, the downhole welding protection system is used for protecting the normal work of the main control signal integrated system and the signal output integrated system; the main control signal integrated system is used for executing welding process logic and realizing digital and intelligent control of the welding process; the signal output integrated system is used for receiving the instruction of the main control signal integrated system, transforming, amplifying and adjusting input electric energy, and outputting current and voltage meeting the downhole welding process requirement. The provided digital power supply system special for in-well welding can realize safe, stable and controllable welding operation in an extremely small space, restores the mechanical strength and sealing integrity of a pipe column in the well, prolongs the service life of the oil well and reduces the maintenance cost.

Description

Technical Field

[0001] This invention relates to the oilfield field, and more specifically to a digital power supply system for a welding machine specifically designed for welding inside wellbores. Background Technology

[0002] In oilfield well workover operations, localized damage to tubing or downhole tools caused by corrosion, wear, or mechanical stress remains a long-standing technical challenge. Traditional repair methods primarily rely on retrieving the entire tubing string for surface repair or replacement. This approach requires extensive use of heavy equipment, is time-consuming and costly, and carries significant well control safety risks during the tubing string handling process. While attempts have been made to miniaturize surface welding technology for downhole applications, conventional welding power sources struggle to withstand the extreme conditions of high temperatures, high pressures, limited space, and corrosive media within the wellbore. They generally suffer from bulky size, insufficient heat dissipation, poor electromagnetic compatibility, and low resistance to vibration and shock. In particular, the lack of systematic protection and intelligent control capabilities for the complex downhole environment leads to unstable welding processes, uncontrollable repair quality, and even the potential for secondary accidents due to equipment failure.

[0003] Therefore, there is an urgent need in this field for a dedicated welding power supply system that can adapt to the harsh downhole environment and has high reliability, high stability and intelligent control capabilities, so as to achieve efficient, safe and high-quality downhole in-situ repair operations. Summary of the Invention

[0004] The purpose of this invention is to provide a digital power supply system for a welding machine specifically designed for welding inside wellbores. This digital power supply system, designed for welding inside wellbores, enables safe, stable, and controllable welding operations in extremely confined spaces, restores the mechanical strength and sealing integrity of the tubing string inside the wellbore, extends the life of the oil well, and reduces maintenance costs.

[0005] The objective of this invention is achieved through the following technical solution:

[0006] A digital power supply system for a welding machine specifically designed for welding inside wells includes an underground welding protection system and a main control signal integration system and a signal output integration system installed within the underground welding protection system.

[0007] The downhole welding protection system is used to protect the main control signal integration system and the signal output integration system to ensure normal operation.

[0008] The main control signal integration system is used to execute welding process logic and realize digital and intelligent control of the welding process;

[0009] The signal output integrated system is used to receive instructions from the main control signal integrated system, transform, amplify and regulate the input electrical energy, and output current and voltage that meet the requirements of the underground welding process.

[0010] The downhole welding protection system includes a downhole welding protection shell, and a fixed base is installed inside the downhole welding protection shell.

[0011] The upper end of the downhole welded protective shell is installed on the coiled tubing, and the lower end of the downhole welded protective shell is installed on the tool housing. The downhole welded protective shell has elongated holes and sealing ring grooves.

[0012] The main control signal integration system includes circuit board wires and a PCB board mounted on the circuit board wires. Pins are installed on the PCB board, and the circuit board wires are mounted on a fixed base.

[0013] The PCB board integrates a microprocessor, a digital signal processor, a memory, and peripheral chips; the circuit board lines are used to transmit PWM control signals, feedback signals, and communication data; the pins are used to achieve physical separation of the PWM control signals and power drive.

[0014] The signal output integrated system includes a large-capacity electrolytic capacitor, transformer, IGBT, heat sink, polyester capacitor, ceramic capacitor, output inductor, and high-voltage ceramic safety capacitor mounted on the PCB board.

[0015] The large-capacity electrolytic capacitor is used to provide instantaneous energy and filter out power frequency ripple; the transformer is used to isolate the input high voltage from the low voltage output of welding, and reduce the high-frequency AC power generated by the inverter to a voltage level suitable for welding; the IGBT is used to invert the DC bus voltage into a high-frequency AC square wave under the drive of the PWM control signal, and to control the average power output to the transformer by changing the duty cycle of the PWM control signal, thereby realizing the regulation of welding current and voltage.

[0016] The heat sink is attached to the IGBT and is used to dissipate heat from the IGBT. A temperature controller is installed on the heat sink. instrument Temperature control instrument Used for real-time monitoring of radiator temperature.

[0017] The polyester capacitor is used to absorb voltage spikes and high-frequency oscillations generated during the switching process of the power supply system, protecting the IGBT from voltage breakdown; the ceramic capacitor is used to provide the shortest discharge path for extremely high frequency current changes; and the output inductor is used to smooth the high-frequency pulse current of the inverter output.

[0018] The high-voltage ceramic safety capacitor is used to reduce conducted electromagnetic interference.

[0019] The beneficial effects of this invention are as follows:

[0020] This invention provides equipment support for in-situ welding repair of downhole tubing and tools. Through the coordinated operation of a downhole welding protection system, a main control signal integration system, and a signal output integration system, it effectively overcomes the extreme environmental limitations of high pressure, high temperature, and limited space within the wellbore. It successfully introduces digital welding technology into repair operations in wells thousands of meters deep, achieving high-strength metallurgical bonding repair of damaged areas and solving the industry problem of structural repair that traditional mechanical seals or chemical plugging methods cannot achieve.

[0021] This invention improves the precision control and quality stability of the welding process. The main control signal integration system of this invention can perform high-precision programming and real-time closed-loop control of welding current, voltage and dynamic parameters. Combined with the synergistic effect of multi-level capacitor networks and output inductors, it effectively suppresses current fluctuations and electromagnetic interference, ensuring the stability of the welding arc and the consistency of the forming quality, and overcoming the adverse effects of complex downhole working conditions on the welding process.

[0022] The intelligent temperature control and heat dissipation system integrated in this invention enables real-time monitoring and thermal management of the operating status of power devices. Through active heat dissipation and over-temperature protection mechanisms, it ensures the long-term reliable operation of the power system in a closed well environment, avoids the risk of equipment failure due to overheating, and improves the environmental adaptability and service life of the overall system.

[0023] This invention offers a significant balance between economic benefits and operational safety. It provides a technical means to complete high-quality repairs without removing the tubing string, greatly shortening the well workover cycle, reducing operating costs and resource consumption. Simultaneously, through electrical isolation, safety protection, and sealing design, it effectively eliminates potential electrical safety hazards in the well, providing innovative technical support for the efficient development and safe production of oilfields.

[0024] The technical principles and system architecture of this invention, after adaptive adjustments, can also be applied to urban underground pipe network systems, chemical and energy pipelines, and other fields that require structural reinforcement and leak repair within cavities or confined spaces. Attached Figure Description

[0025] The present invention will now be described in further detail with reference to the accompanying drawings and specific implementation methods.

[0026] Figure 1 This is a schematic diagram of the overall structure of the digital power supply system for the welding machine specifically designed for welding inside wells according to the present invention;

[0027] Figure 2 This is a schematic diagram of the downhole welding protection system of the present invention;

[0028] Figure 3 This is a schematic diagram of the main control signal integration system structure of the present invention;

[0029] Figure 4 This is a three-dimensional structural diagram of the signal output integrated system of the present invention;

[0030] Figure 5 This is a front view of the signal output integrated system structure of the present invention;

[0031] Figure 6 This is a top view of the signal output integrated system structure of the present invention;

[0032] Figure 7 This is a rear view of the signal output integrated system structure of the present invention;

[0033] Figure 8 This is an exploded view of the signal output integrated system structure of the present invention.

[0034] In the picture:

[0035] 1. Downhole welding protection system; 1.1. Downhole welding protection shell; 1.2. Fixing base;

[0036] 2. Main control signal integration system; 2.1 PCB board; 2.2 Circuit board wires; 2.3 Pins;

[0037] Signal output integrated system 3; large-capacity electrolytic capacitor 3.1; transformer 3.2; IGBT 3.3; heat sink 3.4; temperature control instrument 3.5; Polyester capacitor 3.6; Ceramic capacitor 3.7; Output inductor 3.8; High-voltage ceramic safety capacitor 3.9. Detailed Implementation

[0038] The present invention will now be described in further detail with reference to the accompanying drawings.

[0039] like Figures 1 to 8 As shown below, the structure and function of the digital power supply system for the welding machine specifically designed for welding inside the well shaft will be described in detail.

[0040] A digital power supply system for a welding machine specifically designed for welding inside wells includes an underground welding protection system 1, a main control signal integration system 2, and a signal output integration system 3 installed within the underground welding protection system 1.

[0041] The downhole welding protection system 1 is used to protect the main control signal integration system 2 and the signal output integration system 3 so that they can operate normally.

[0042] The main control signal integration system 2 is responsible for executing the welding process logic, realizing the digital and intelligent control of the welding process, and coordinating the orderly transmission of electrical signals.

[0043] The signal output integration system 3 is used to receive instructions from the main control signal integration system 2, transform, amplify and regulate the input electrical energy, and output welding current and voltage that meet the requirements of the downhole welding process.

[0044] The downhole welding protection system 1 includes a downhole welding protection shell 1.1, and a fixed base 1.2 is installed inside the downhole welding protection shell 1.1. The fixed base 1.2 is used to fix and install other parts so that different systems can work together.

[0045] The upper end of the downhole welded protective shell 1.1 is threaded onto the coiled tubing, and the lower end of the downhole welded protective shell 1.1 is threaded onto the tool housing. An elongated hole is provided at the downhole welded protective shell 1.1 for the downhole tool to extend. Sealing ring grooves are provided on both sides of the elongated hole to achieve sealing of the downhole welded protective shell 1.1.

[0046] The main control signal integration system 2 includes a circuit board line 2.2 and a PCB board 2.1 mounted on the circuit board line 2.2. The PCB board 2.1 is equipped with pins 2.3, and the circuit board line 2.2 is mounted on a fixed base 1.2.

[0047] The PCB board 2.1 integrates a microprocessor, a digital signal processor, a memory, and peripheral chips, forming a complete control circuit. Through precise wiring, it provides stable power supply voltage and a clear, low-noise signal transmission path for all components.

[0048] The circuit board line 2.2 is used to transmit PWM control signals, feedback signals, and communication data;

[0049] The pin 2.3 is used to physically separate the PWM control signal from the power drive, which facilitates assembly, testing and maintenance.

[0050] The signal output integrated system 3 includes a large-capacity electrolytic capacitor 3.1, a transformer 3.2, an IGBT 3.3, a heat sink 3.4, a polyester capacitor 3.6, a ceramic capacitor 3.7, an output inductor 3.8, and a high-voltage ceramic safety capacitor 3.9, all mounted on a PCB board 2.1.

[0051] The large-capacity electrolytic capacitor 3.1 is used to provide a huge instantaneous energy during the high current output at the moment of welding, ensuring the stability of the welding process. At the same time, it can filter out the power frequency ripple after rectification, providing a smooth and stable DC voltage source for the subsequent inverter circuit.

[0052] The transformer 3.2 is used to isolate the input high voltage from the welding output low voltage, ensuring operational and equipment safety. At the same time, it reduces the high-frequency AC power generated by the inverter to a voltage level suitable for welding, thereby efficiently transferring the power from the front stage to the back stage.

[0053] The IGBT 3.3 is used to invert the DC bus voltage into a high-frequency AC square wave under the drive of the PWM control signal, and to control the average power output to the transformer 3.2 by changing the duty cycle of the PWM control signal, thereby realizing the regulation of welding current and voltage.

[0054] The heat sink 3.4 is attached to the IGBT 3.3 and is used to dissipate heat from the IGBT 3.3, quickly removing the huge amount of heat generated by the IGBT 3.3 during operation from its casing.

[0055] A temperature controller 3.5 is installed on the radiator 3.4. The temperature controller 3.5 is used to monitor the temperature of the radiator 3.4 in real time. When the temperature exceeds the preset safety threshold, the system will immediately take protective measures such as reducing power or completely shutting down the output to prevent the equipment from burning out due to overheating.

[0056] The polyester capacitor 3.6 is used to absorb voltage spikes and high-frequency oscillations generated during the switching process of the power system, protecting the IGBT 3.3 from voltage breakdown.

[0057] The ceramic capacitor 3.7 is used to provide the shortest discharge path for extremely high frequency current changes, eliminate high frequency ringing caused by parasitic parameters, ensure the purity of the drive signal and the cleanness of the switching waveform, thereby effectively suppressing the propagation of high frequency electromagnetic interference.

[0058] The output inductor 3.8 is used to smooth the high-frequency pulse current output by the inverter, so as to output a continuous and stable DC welding current and reduce welding spatter.

[0059] The high-voltage ceramic safety capacitor 3.9 is used to reduce conducted electromagnetic interference, enabling the equipment to meet EMC standards. Even if it fails, it will remain in an open circuit state, preventing short circuits and avoiding the risk of electric shock.

[0060] like Figures 1 to 8 As shown below, an embodiment of a digital power supply system for a welding machine specifically designed for welding inside wells will be described in detail.

[0061] Ground assembly and debugging:

[0062] On the ground, install the fixed base 1.2 inside the underground welded protective shell 1.1. Then, install the main control signal integration system 2 in sequence. Install the circuit board wire 2.2 onto the fixed base 1.2, the PCB board 2.1 onto the circuit board wire 2.2, and the pins 2.3 onto the PCB board 2.1. Next, install the signal output integration system 3 in sequence, including the large-capacity electrolytic capacitor 3.1, transformer 3.2, IGBT 3.3, heat sink 3.4, and temperature controller. instrument3.5, 3.6, 3.7, 3.8, 3.9, 3.5, 3.8, 3.9, 3.0, 3.1, 3.2, 3.3, 3.4, and 3.5, 3.6, 3.7, 3.8, and 3.9, 3.4, 3.3, 3.4, 3.3, 3.5, 3.6, 3.7, 3.8, 3.9, 3.8, 3.9, 3.0, 3.1, 3.2, 3.3, 3.4, 3.3, 3.8, 3.9, 3.0, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7 ...

[0063] Tools are lowered into the well for operation:

[0064] The tool string is lowered to the target welding area downhole via coiled tubing. Upon reaching the designated position, the main control signal integration system 2 is powered on and initialized, controlled by temperature... instrument 3.5 Real-time monitoring of the heatsink temperature (3.4). After the soldering command is issued, the PCB board (2.1) sends a PWM control signal, which is transmitted to the IGBT (3.3) via the circuit board line (2.2), converting the DC bus voltage into a high-frequency AC square wave; the transformer (3.2) performs voltage transformation and electrical isolation; the large-capacity electrolytic capacitor (3.1) provides instantaneous energy support; the polyester capacitor (3.6) and ceramic capacitor (3.7) work together to suppress voltage spikes and high-frequency oscillations; and the output inductor (3.8) smooths the high-frequency pulse current, outputting a stable and reliable soldering current. The entire process is controlled by temperature control. instrument 3.5 Continuously monitor the radiator temperature. 3.4 When the temperature exceeds the preset threshold, automatic protection measures will be taken.

[0065] Tool recycling:

[0066] After the soldering process is completed, the power system is shut down in an orderly manner. The tool string is lifted smoothly to the ground, disassembled, and the surface of the heat sink 3.4 is cleaned. The working status of each capacitor and IGBT 3.3 on the PCB board 2.1 is checked, the connection reliability of the pins 2.3 is tested, and the operating data recorded by the main control signal integration system 2 is downloaded and analyzed to provide an optimization basis for subsequent operations.

[0067] It should be noted that while preferred embodiments of this application are provided in the specification and accompanying drawings, this application can be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are not intended to impose additional limitations on the content of this application; their purpose is to provide a more thorough and comprehensive understanding of the disclosure of this application. Furthermore, the above-described technical features can be combined with each other to form various embodiments not listed above, all of which are considered to be within the scope of this specification. Moreover, those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A digital power supply system for a welding machine specifically designed for welding inside well shafts, comprising an underground welding protection system (1) and a main control signal integration system (2) and a signal output integration system (3) installed within the underground welding protection system (1), characterized in that: The downhole welding protection system (1) is used to protect the main control signal integration system (2) and the signal output integration system (3) so that they can work normally. The main control signal integration system (2) is used to execute welding process logic and realize digital and intelligent control of the welding process; The signal output integration system (3) is used to receive instructions from the main control signal integration system (2), transform, amplify and regulate the input electrical energy, and output current and voltage that meet the requirements of the underground welding process.

2. The digital power supply system for a welding machine specifically designed for welding inside well shafts according to claim 1, characterized in that: The downhole welding protection system (1) includes a downhole welding protection shell (1.1), and a fixed base (1.2) is installed inside the downhole welding protection shell (1.1).

3. The digital power supply system for a welding machine specifically designed for welding inside well shafts according to claim 2, characterized in that: The upper end of the downhole welded protective shell (1.1) is installed on the coiled tubing, and the lower end of the downhole welded protective shell (1.1) is installed on the tool housing. The downhole welded protective shell (1.1) has elongated holes and sealing ring grooves.

4. The digital power supply system for a welding machine specifically designed for welding inside well shafts according to claim 2, characterized in that: The main control signal integration system (2) includes a circuit board line (2.2) and a PCB board (2.1) mounted on the circuit board line (2.2). Pins (2.3) are mounted on the PCB board (2.1), and the circuit board line (2.2) is mounted on a fixed base (1.2).

5. The digital power supply system for a welding machine specifically designed for welding inside well shafts according to claim 4, characterized in that: The PCB board (2.1) integrates a microprocessor, a digital signal processor, a memory, and peripheral chips; the circuit board lines (2.2) are used to transmit PWM control signals, feedback signals, and communication data; the pins (2.3) are used to achieve physical separation of PWM control signals and power drive.

6. The digital power supply system for a welding machine specifically designed for welding inside well shafts according to claim 2, characterized in that: The signal output integrated system (3) includes a large-capacity electrolytic capacitor (3.1), a transformer (3.2), an IGBT (3.3), a heat sink (3.4), a polyester capacitor (3.6), a ceramic capacitor (3.7), an output inductor (3.8), and a high-voltage ceramic safety capacitor (3.9) mounted on a PCB board (2.1).

7. The digital power supply system for a welding machine specifically designed for welding inside well shafts according to claim 6, characterized in that: The large-capacity electrolytic capacitor (3.1) is used to provide instantaneous energy and filter out power frequency ripple; the transformer (3.2) is used to isolate the input high voltage from the low voltage output of welding and reduce the high-frequency AC power generated by the inverter to a voltage level suitable for welding; the IGBT (3.3) is used to invert the DC bus voltage into a high-frequency AC square wave under the drive of the PWM control signal, and to control the average power output to the transformer (3.2) by changing the duty cycle of the PWM control signal, thereby realizing the regulation of welding current and voltage.

8. The digital power supply system for a welding machine specifically designed for welding inside well shafts according to claim 6, characterized in that: The heat sink (3.4) is attached to the IGBT (3.3) and is used to dissipate heat from the IGBT (3.3). A temperature controller is installed on the heat sink (3.4). instrument (3.5), Temperature control instrument (3.5) is used to monitor the temperature of the radiator (3.4) in real time.

9. The digital power supply system for a welding machine specifically designed for welding inside well shafts according to claim 6, characterized in that: The polyester capacitor (3.6) is used to absorb the voltage spikes and high-frequency oscillations generated during the switching process of the power supply system, and to protect the IGBT (3.3) from voltage breakdown; the ceramic capacitor (3.7) is used to provide the shortest discharge path for extremely high frequency current changes; the output inductor (3.8) is used to smooth the high-frequency pulse current of the inverter output.

10. The digital power supply system for a welding machine specifically designed for welding inside well shafts according to claim 6, characterized in that: The high-voltage ceramic safety capacitor (3.9) is used to reduce conducted electromagnetic interference.

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