Method for improving reliability of high-temperature special power transformer for oil field logging
By optimizing the transformer material selection, design and process, the reliability problem of high-temperature special power transformers used for oilfield logging when operating in harsh environments has been solved, and the effects of reducing temperature rise and extending equipment life have been achieved.
Patent Information
- Application Number
- CN202411542322.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-31
- Publication Date
- 2025-01-21
AI Technical Summary
When high-temperature special power transformers for well logging in oil fields are operating in harsh environments, they face the dual challenges of high temperature, high humidity and corrosive gases, resulting in low electrical performance reliability and high inspection and maintenance costs.
By optimizing the transformer material selection, design level and process level, we select high-temperature resistant enameled wires, skeletons, insulating materials and solder wires, optimize core materials and assembly processes, reduce no-load current and coil losses, and use interlayer insulation. method and vacuum-pressure cycle impregnation process to improve the heat dissipation effect.
It effectively improves the reliability of the transformer, reduces the temperature rise, extends the service life of the equipment, reduces maintenance costs, and ensures stable operation in high temperature environments.
Smart Images
Figure CN119340093A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of transformer design, and in particular to a method for improving the reliability of a high-temperature special power transformer for oilfield logging. Background Art
[0002] The general structure of high temperature special power transformer for oil field logging is as follows: Figure 1 The transformer is used in a harsh environment with high temperature, high humidity, and the presence of corrosive hydrogen sulfide gas. When logging in deep formations, transformer inspection and maintenance costs are high and the difficulty is high. As an important component of power transmission, the reliability of the electrical performance of the transformer is particularly important.
[0003] High ambient temperature is the biggest problem faced when designing oilfield logging transformers. The ambient temperature is generally divided into 175℃ and 200℃ levels. In extreme cases, it is required to reach 230℃. This requires that the temperature resistance must be considered in the selection of enameled wire, skeleton material, insulation material, and solder wire for welding when designing the transformer.
[0004] The transformer itself will have a temperature rise during operation, and the ambient temperature cannot be artificially reduced, so the transformer temperature rise must be controlled to be as small as possible, which can be achieved by reducing the iron loss and copper loss of the transformer. Selecting a silicon steel strip wound core with high saturation magnetic induction intensity and low loss grade, and controlling the joint degree of the joint surface during transformer assembly can reduce the no-load current; at the same time, the saturation magnetic induction intensity and current density values cannot be too high, and low values will lead to a larger transformer size and installation problems. The temperature rise will cause the temperature to accumulate inside the transformer, and the insulation performance of the enameled wire and insulating materials will be reduced or even fail at high temperatures, resulting in poor transformer withstand voltage or even short circuit and burnout; the lead wire welding points may also desolder at high temperatures, resulting in poor contact, so the heat dissipation of the transformer must be considered. Summary of the invention
[0005] The object of the present invention is to provide a method for improving the reliability of a high-temperature special power transformer for oil field logging, so as to solve the problems in the background technology.
[0006] In order to solve the above technical problems, the present invention provides a method for improving the reliability of a high-temperature special power transformer for oilfield logging, comprising:
[0007] From the transformer material selection aspect, different types of enameled wires, skeletons, insulation materials and solder wires are selected according to different ambient temperatures, taking into account cost and reliability;
[0008] From the design perspective, the no-load current and coil loss can be reduced by selecting core materials, adjusting assembly processes, and optimizing parameter values.
[0009] From a technological perspective, the windings of high-temperature special power transformers used in oilfield logging use interlayer insulation to achieve heat dissipation.
[0010] In one embodiment, the transformer material selection includes:
[0011] At an ambient temperature of 175°C, the enameled wire is polyamide-imide I220 type -2 paint film enameled wire, the transformer winding skeleton is assembled with 3240 brand epoxy board, the insulation material is polyimide 0.05 film or tape, and the welding is lead-free solder wire;
[0012] At an ambient temperature of 200°C, the enameled wire is polyimide ML240 type -2 paint film enameled wire, the transformer winding skeleton is assembled with FR-4 water green epoxy board, the insulation material is polyimide 0.05 film or tape, and the welding is solder wire with a melting point above 296°C;
[0013] In ultra-high temperature environment of 230℃, aromatic polyimide QY-2 / 260 enameled wire is selected for enameled wire, polyetheretherketone peek material or polyimide pi board is selected for transformer winding skeleton, polyimide 0.05 film or tape is used as insulating material, and solder wire with a melting point above 296℃ is selected for welding.
[0014] In one embodiment, the design level includes:
[0015] At power frequency or slightly higher frequency, choose the iron core wound with Japanese Kawasaki 23JGSD085 oriented silicon steel strip or Baosteel B23P085 oriented silicon steel strip of equivalent material;
[0016] When packaging the transformer core, adjust the fit of the core bonding surface, add high-temperature white tape or epoxy sheet less than 0.5mm to adjust the core bonding surface; before packaging and assembly, use 600 mesh and 1000 mesh sandpaper to polish the core cutting surface to increase the bonding degree; use solder wire with a melting point above 296℃ to fix the core chuck.
[0017] In one embodiment, the saturation magnetic induction intensity of the transformer is designed to be 1.5T; the current density is 2.5A / mm 2 .
[0018] In one embodiment, the process level includes:
[0019] The winding of the high-temperature special power transformer used in oil field logging should adopt interlayer insulation, with a layer of 0.05 polyimide film padded between layers, and a 2-3mm margin on each side of the skeleton.
[0020] In one embodiment, the high temperature special power transformer for oilfield logging is impregnated with paint by vacuum-pressure cycle impregnation: the transformer is pre-baked as a whole to 120-135° C. for 1 hour, then cooled to 40° C., and the S-grade insulating paint of ELANTAS V-1380FC is selected for impregnation, and the transformer is completely immersed in the insulating paint; the whole is evacuated to below 2 cmHg and maintained for at least 5 minutes, and the vacuum is broken and immersed for 5 minutes, and then the vacuum is evacuated to 2 cmHg again and maintained for 15 minutes. After breaking the vacuum and soaking for 5 minutes, the pressure is increased to 0.1 MPa and maintained for 10 minutes. After the transformer is taken out and the paint is dripped for 10 minutes, it is heated to 135° C. and maintained for 4 hours, and the insulating paint is fully cured.
[0021] The invention provides a method for improving the reliability of a high-temperature special power transformer for oilfield logging, which improves the reliability of the transformer through reliable design and feasible process. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] Figure 1 It is a general structural diagram of a high-temperature special power transformer for oil field logging. DETAILED DESCRIPTION
[0023] The following is a further detailed description of a method for improving the reliability of a high-temperature special power transformer for oilfield logging proposed by the present invention in conjunction with the accompanying drawings and specific embodiments. The advantages and features of the present invention will become clearer according to the following description. It should be noted that the accompanying drawings are all in a very simplified form and are not in precise proportions, and are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the present invention.
[0024] 1. Transformer material selection
[0025] At an ambient temperature of 175°C, considering cost and reliability, the enameled wire should preferably be the polyamide-imide I220 type -2 paint film enameled wire produced by Elektrisola Group; the transformer winding skeleton should be assembled with 3240 brand epoxy board to meet the requirements; the insulating material can be polyimide 0.05 film or tape, and the solder wire for welding can be ordinary lead-free solder wire to meet the requirements.
[0026] At an ambient temperature of 200°C, considering cost and reliability, the enameled wire should preferably be the polyimide ML240 type -2 paint film enameled wire produced by Elektrisola Group; the transformer winding skeleton should be assembled with FR-4 aqua green epoxy board to meet the requirements; the insulating material can be polyimide 0.05 film or tape, and the solder wire for welding should have a melting point above 296°C to meet the requirements.
[0027] Under ultra-high temperature of 230℃, the enameled wire should be the aromatic polyimide QY-2 / 260 enameled wire produced by Huzhou Xindeyi Special Electromagnetic Wire Co., Ltd.; the transformer winding skeleton should be assembled with polyetheretherketone peek material or polyimide pi board; the insulating material can be polyimide 0.05 film or tape, and the solder wire for welding should have a melting point above 296℃ to meet the requirements.
[0028] 2. Design considerations
[0029] Reducing no-load current and coil losses can reduce temperature rise, which can be achieved through core material selection, assembly process adjustment, and parameter value optimization.
[0030] At industrial frequency or slightly higher frequency, choose an iron core wound with Japanese Kawasaki 23JGSD085 oriented silicon steel strip or Baosteel B23P085 oriented silicon steel strip of equivalent material. The iron loss of the core is low and the temperature rise can be effectively reduced.
[0031] When packaging the transformer core, the degree of fit of the core bonding surface should be adjusted. High-temperature white tape or epoxy sheet less than 0.5mm can be added to adjust the core bonding surface to prevent the core from tilting during the packaging and assembly of the core strapping steel belt, which will increase the air gap and increase the no-load current. It is also necessary to polish the core cutting surface with 600 mesh and 1000 mesh sandpaper before packaging and assembly to increase the bonding degree, which can reduce the no-load current and temperature rise to a certain extent. The solder wire used to fix the core clamp should have a melting point above 296℃ to prevent the clamp from loosening at high temperature, causing the core to be unable to be effectively combined, resulting in a sharp increase in the transformer no-load current.
[0032] When designing a transformer, the value of saturation magnetic induction intensity should be reasonable. If the value is too large, the no-load current will be large and the temperature rise will increase. If the value is too low, the transformer coil size will be out of tolerance and affect assembly. Generally, 1.5T is more reasonable. The value of current density has a greater impact on iron loss. If the value is too low, the transformer coil size will be out of tolerance and affect assembly. If the value is too high, the coil copper loss will increase and affect temperature rise. Generally, 2.5A / mm 2 More reasonable.
[0033] 3. Process considerations
[0034] In order to effectively dissipate heat, the winding of the high-temperature special power transformer used in oilfield logging should adopt interlayer insulation. A layer of polyimide 0.05 film should be added between the layers, and a 2-3mm margin should be left on both sides of the skeleton, which is similar to adding a heat dissipation channel. It can also effectively avoid short circuits between layers and cause overall failure of the transformer.
[0035] The high-temperature special power transformer for oilfield logging should be impregnated with vacuum-pressure cycle impregnation. The transformer is pre-baked to 120-135℃ for 1 hour, then cooled to about 40℃, and impregnated with ELANTAS V-1380FC S-class insulating paint. Note that the transformer should be completely immersed in the insulating paint; the whole is evacuated to below 2cmHg and kept for at least 5 minutes, and then soaked for 5 minutes after breaking the vacuum, and then evacuated to about 2cmHg and kept for 15 minutes. After breaking the vacuum and soaking for 5 minutes, pressurize to about 0.1Mpa and keep for 10 minutes, take out the transformer and drip paint for 10 minutes, then heat to 135℃ and keep for about 4 hours, and the insulating paint can be fully cured. Through this process of impregnation, the coil will be fully impregnated with insulating paint. The thermal conductivity of the paint film formed after the insulating paint is cured is much greater than that of air, which can play a better role in heat dissipation and help reduce temperature rise; at the same time, the cured insulating paint can effectively prevent moisture and corrosive hydrogen sulfide gas from the formation from invading the coil, preventing short circuit problems caused by poor insulation performance of the transformer or damage to the coil paint film.
[0036] The above description is only a description of the preferred embodiments of the present invention, and is not intended to limit the scope of the present invention. Any changes or modifications made by a person skilled in the art in the field of the present invention based on the above disclosure shall fall within the scope of protection of the claims.
Claims
1. A method for improving the reliability of a high-temperature special power transformer for oilfield logging, characterized in that: include: From the transformer material selection aspect, different types of enameled wires, skeletons, insulation materials and solder wires are selected according to different ambient temperatures, taking into account cost and reliability; From the design perspective, the no-load current and coil loss can be reduced by selecting core materials, adjusting assembly processes, and optimizing parameter values. From a technological perspective, the windings of high-temperature special power transformers used in oilfield logging use interlayer insulation to achieve heat dissipation.
2. The method for improving the reliability of a high temperature special power transformer for oilfield logging according to claim 1, characterized in that: The transformer material selection aspect includes: At an ambient temperature of 175°C, the enameled wire is polyamide-imide I220 type -2 paint film enameled wire, the transformer winding skeleton is assembled with 3240 brand epoxy board, the insulation material is polyimide 0.05 film or tape, and the welding is lead-free solder wire; At an ambient temperature of 200°C, the enameled wire is polyimide ML240 type -2 paint film enameled wire, the transformer winding skeleton is assembled with FR-4 water green epoxy board, the insulation material is polyimide 0.05 film or tape, and the welding is solder wire with a melting point above 296°C; In ultra-high temperature environment of 230℃, aromatic polyimide QY-2 / 260 enameled wire is selected for enameled wire, polyetheretherketone peek material or polyimide pi board is selected for transformer winding skeleton, polyimide 0.05 film or tape is used as insulating material, and solder wire with a melting point above 296℃ is selected for welding.
3. The method for improving the reliability of a high temperature special power transformer for oilfield logging according to claim 1, characterized in that: The design aspects include: At power frequency or slightly higher frequency, choose the iron core wound with Japanese Kawasaki 23JGSD085 oriented silicon steel strip or Baosteel B23P085 oriented silicon steel strip of equivalent material; When packaging the transformer core, adjust the fit of the core bonding surface, add high-temperature white tape or epoxy sheet less than 0.5mm to adjust the core bonding surface; before packaging and assembly, use 600 mesh and 1000 mesh sandpaper to polish the core cutting surface to increase the bonding degree; use solder wire with a melting point above 296℃ to fix the core chuck.
4. The method for improving the reliability of a high temperature special power transformer for oilfield logging as claimed in claim 3, characterized in that: The saturation magnetic induction intensity of the transformer is 1.5T; the current density is 2.5A / mm 2 .
5. The method for improving the reliability of a high temperature special power transformer for oilfield logging as claimed in claim 1, characterized in that: The process level includes: The winding of the high-temperature special power transformer used in oil field logging should adopt interlayer insulation, with a layer of 0.05 polyimide film padded between layers, and a 2-3mm margin on each side of the skeleton.
6. The method for improving the reliability of a high temperature special power transformer for oilfield logging as claimed in claim 5, characterized in that: The high temperature special power transformer for oilfield logging is impregnated with paint by vacuum-pressure cycle impregnation: the transformer is pre-baked as a whole to 120-135° C. for 1 hour, then cooled to 40° C., and impregnated with S-grade insulating paint of ELANTAS V-1380FC, and the transformer is completely immersed in the insulating paint; the whole is evacuated to below 2 cmHg for at least 5 minutes, and then immersed for 5 minutes after breaking the vacuum, and then evacuated to 2 cmHg again for 15 minutes, and then pressurized to 0.1 Mpa for 10 minutes after breaking the vacuum and soaking for 5 minutes, and then the transformer is taken out to drip paint for 10 minutes, and then heated to 135° C. for 4 hours, and the insulating paint is fully cured.