Aluminum alloy photovoltaic cable processing method and system

Abstract

The invention discloses an aluminum alloy photovoltaic cable processing method and system, and the method comprises the following steps: S1, conductor pretreatment: employing an aluminum alloy wire as a conductor, firstly carrying out plasma activation treatment on the aluminum alloy wire, then coating the surface with an Al2O3-SiO nano ceramic coating, and after coating, carrying out sintering treatment to form a compact protection layer; s2, conductor twisting: twisting a plurality of aluminum alloy wires into a cable core; s3, extrusion of an insulating layer: preparing a three-layer co-extrusion structure of a nano ceramic filling insulating layer, a semi-conductive waterproof layer and a weather-proof insulating layer; and S4, manufacturing the sheath. The extruded insulating layer is scanned in real time through the system, spectral data are collected, and the working state of the extrusion unit is adjusted in real time based on preset process parameters. According to the method, plasma treatment and the nano ceramic coating technology are combined and applied to surface treatment of the aluminum alloy photovoltaic cable conductor, compared with a traditional electroplating or chemical plating process, the environmental protection property is remarkably improved, and plasma treatment parameters and the deposition condition of the ceramic coating are accurately controlled.

Description

Technical Field

[0001] This invention belongs to the field of cables, and specifically relates to a cable processing method and system. Background Technology

[0002] In photovoltaic power generation systems, cables serve as the core carrier for power transmission, and their performance directly affects the system's safety, efficiency, and lifespan. With the trend of "replacing copper with aluminum," the application of aluminum alloy photovoltaic cables is becoming increasingly widespread, but it still faces many technical challenges.

[0003] In existing technologies, the surface treatment of aluminum alloy conductors mostly employs traditional electroplating or chemical plating processes, such as chromate passivation. However, these methods suffer from severe environmental pollution and high costs. Although some technologies have attempted to replace them with electrochemical oxidation processes, they still fall short of the high conductivity and weather resistance requirements of photovoltaic cables. For example, when the oxide film thickness on the aluminum alloy surface exceeds 5μm after traditional electrochemical oxidation treatment, it reaches an insulating state, affecting conductivity.

[0004] In terms of cable processing technology, existing technologies mainly focus on the extrusion molding of the insulation layer and the structural design of the cable. For example, some patents improve weather resistance by improving insulation materials, such as using irradiated cross-linked polyolefins, but the uniformity control of the insulation layer thickness still relies on offline detection, making it difficult to achieve real-time monitoring and adjustment.

[0005] Furthermore, the automation and intelligence levels of existing cable processing systems need improvement. Although patents have proposed automated traction devices for multi-core cable processing, integrated processing solutions for the unique conductor pretreatment, insulation extrusion, and online inspection of aluminum alloy photovoltaic cables remain insufficient. Particularly in the area of ​​online inspection of photovoltaic cables, existing technologies mostly employ infrared thermal imaging and other techniques during the operation and maintenance phase, lacking effective means for real-time monitoring of insulation quality during processing.

[0006] In summary, existing technologies for aluminum alloy photovoltaic cables have the following shortcomings in conductor surface treatment, insulation processing technology, and system integration: the anti-oxidation treatment process for aluminum alloy conductors is not environmentally friendly and affects conductivity; the thickness uniformity control in the insulation extrusion process is insufficient, relying on offline detection; and the insulation processing system lacks integrated design for conductor pretreatment, extrusion molding, and online detection, resulting in low automation. Summary of the Invention

[0007] The purpose of this invention is to provide a processing method and system for aluminum alloy photovoltaic cables. Through innovative conductor pretreatment process, optimized insulation extrusion process and integrated processing system, the oxidation resistance, conductivity and weather resistance of aluminum alloy photovoltaic cables are improved, while processing efficiency and product quality stability are enhanced.

[0008] To achieve the above objectives, the technical solution adopted by this invention is as follows: A method for processing aluminum alloy photovoltaic cables includes the following steps: S1 Conductor pretreatment: The conductor is an aluminum alloy wire. First, the aluminum alloy wire is subjected to plasma activation treatment, and then an Al2O3-SiO2 nano-ceramic coating is coated on the surface. After coating, a sintering treatment is performed to form a dense protective layer. S2 conductor stranding: multiple aluminum alloy wires are stranded together to form a cable core; S3 Insulation Layer Extrusion: Preparation of a three-layer co-extrusion structure of nano-ceramic filled insulation layer-semi-conductive resistive water layer-weather resistant insulation layer; S4: Make a protective sheath.

[0009] For step S1: The surface of the aluminum alloy conductor is subjected to plasma treatment for 30-60 seconds using an Ar / O2 mixed gas; an Al2O3-SiO2 nano-ceramic coating is coated on the activated conductor surface by aerosol deposition, with the carrier gas pressure controlled at 0.5-0.8MPa and the deposition rate at 10-20nm / min during the coating process; after coating, a low-temperature sintering treatment is performed, holding at 300-400℃ for 15-30 minutes to form a dense protective layer with a thickness of 200-300nm.

[0010] The nano-ceramic coating incorporates trace amounts of rare earth element oxide nanoparticles, with the average particle size of both the ceramic particles and the rare earth oxides controlled at 50-100 nm. (These trace rare earth element oxide nanoparticles (such as Ce and La) further enhance the adhesion between the coating and the conductor, improving the conductor's oxidation resistance and conductivity stability. Rare earth elements can improve the electronic structure of the conductor surface and optimize charge distribution, thereby maintaining more stable conductivity during long-term use.) For step S2: First, a single aluminum alloy wire is pre-twisted to form a small twisted unit, and then multiple small twisted units are twisted a second time to form the final conductor structure.

[0011] For step S3: the material of the nano-ceramic filled insulation layer is polyolefin insulation material with 5-8% silane-modified attapulgite nanoparticles added; the semi-conductive resistive water layer is a semi-conductive polyolefin material containing conductive carbon black; the weather-resistant insulation layer is a halogen-free, low-smoke, flame-retardant cross-linked polyolefin material at 125℃.

[0012] During the three-layer co-extrusion process, the extrusion temperature is controlled at 180-220℃ and the traction speed is 5-15m / min.

[0013] For step S4: The sheath is extruded from halogen-free, low-smoke, flame-retardant cross-linked polyolefin material at 125°C.

[0014] For step S3: During insulation extrusion, the wall thickness, eccentricity, ellipticity, and cable diameter of each layer are detected online. The geometric morphology data of the insulation layer is acquired in real time at high frequency. The detection data is transmitted to the intelligent control system in real time. Feature extraction and analysis are performed on the data to identify potential problems and trends in the insulation layer quality and feed them back to the extruder host. The temperature, pressure, and traction speed of the extruder are automatically adjusted to control the insulation layer thickness deviation within ±0.01mm.

[0015] An aluminum alloy photovoltaic cable processing system includes an extrusion unit, a crosslinking online polarimeter, an infrared spectrometer, a data acquisition system, and an image processing system. The crosslinking online polarimeter and the infrared spectrometer are installed downstream of the extrusion unit to scan the extruded insulation layer in real time. The data acquisition system acquires spectral data at high speed, receives and processes sensor data from each unit, and the image processing system analyzes the thickness and composition distribution of the insulation layer and adjusts the working state of the extrusion unit in real time based on preset process parameters and data algorithms. During insulation extrusion, a combination of online crosslinking polarization measuring instrument and online infrared spectroscopy detection technology is used for control. The online crosslinking polarization measuring instrument detects the wall thickness, eccentricity, ellipticity, and cable diameter of each layer online, acquiring the geometric morphology data of the insulation layer in real time at high frequency. The online infrared spectroscopy detection technology uses an infrared spectrometer with a wavelength range of 3-5μm to scan the compositional uniformity of the insulation layer at a certain frequency. The detection data is transmitted to the intelligent control system in real time. Through big data, AI deep learning algorithms, and analysis of the detection results, feature extraction and analysis are performed on the data to identify potential problems and trends in insulation quality. This information is then fed back to the extruder host, which automatically adjusts the temperature, pressure, and traction speed of the extruder to control the insulation layer thickness deviation within ±0.01mm.

[0016] The beneficial effects of this invention are: This invention abandons the highly polluting processes of traditional electroplating and chemical plating, adopting an environmentally friendly plasma activation-nano-ceramic coating process. This reduces emissions of harmful substances such as chromate, aligning with current green development needs and lowering environmental costs and risks. Simultaneously, a precise online monitoring and real-time control system reduces raw material waste and improves production yield, significantly lowering production costs in the long run and enhancing the company's economic benefits and market competitiveness.

[0017] The "Plasma Activation-Nano-Ceramic Coating" composite pretreatment process is the first to combine plasma treatment with nano-ceramic coating technology for the surface treatment of aluminum alloy photovoltaic cable conductors. Compared with traditional electroplating or chemical plating processes, it not only significantly improves environmental friendliness but also ensures a conductivity ≥61% IACS by precisely controlling plasma treatment parameters and ceramic coating deposition conditions, thereby improving the conductor's oxidation resistance and resolving the contradiction between oxide film thickness and conductivity in existing technologies. Furthermore, the rare earth element oxide nanoparticles added to the nano-ceramic coating further enhance the adhesion between the coating and the conductor, improve the conductor's oxidation resistance and conductivity stability, improve the electronic structure of the conductor surface, and optimize charge distribution, thus maintaining a more stable conductivity during long-term use.

[0018] A three-layer co-extrusion structure consisting of a nano-ceramic filled insulation layer, a semi-conductive water-resistant layer, and a weather-resistant insulation layer is designed. Each layer synergistically enhances insulation, weather resistance, water resistance, and uniform electric field distribution. An online crosslinking polarization analyzer and online infrared spectroscopy detection technology are integrated, leveraging their complementary advantages. The former accurately captures structural parameters, while the latter deeply analyzes component uniformity. Real-time data is processed by the intelligent control system using big data analysis and AI deep learning algorithms to accurately identify quality issues and promptly adjust extruder parameters, controlling thickness deviation within ±0.01mm. This significantly outperforms existing offline detection methods, far exceeding the accuracy and efficiency of traditional offline detection, enabling intelligent quality control during processing and improving product stability.

[0019] Intelligent Monitoring and Feedback System Integration: This system constructs an intelligent monitoring and feedback system with industrial Ethernet as its core, encompassing modules such as infrared spectrometers, data acquisition, and image processing. It efficiently integrates sensor data from various units, adjusting the operating status in real time based on preset process parameters, data analysis, and AI algorithms. Equipped with an intuitive human-machine interface, it facilitates full-process monitoring and timely intervention by operators, achieving visualized and intelligent management of the production process and significantly improving production efficiency and product consistency. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the cable structure.

[0021] In the diagram: 1-Aluminum alloy conductor, 2-Nano ceramic filled insulation layer, 3-Semi-conductive resistive water layer, 4-Weather-resistant insulation layer, 5-Weather-resistant sheath layer. Detailed Implementation

[0022] The present invention will now be described in more detail with reference to the accompanying drawings and embodiments, but the scope of protection is not limited thereto.

[0023] Example 1: The preparation method includes the following steps. S1. Conductor pretreatment: AA8030 aluminum alloy conductors with a diameter of 2.5mm were selected and first degreased and cleaned. The conductor is fed into the plasma pretreatment unit and treated for 45 seconds with an Ar / O2 mixed gas (Ar:O2=3:1) at a power of 100W and a working pressure of 3MPa. This process forms a nanoscale rough structure on the surface, increases the specific surface area, and introduces a large number of active sites. Next, an Al2O3-SiO2 nano-ceramic coating and rare earth oxide nanoparticles (Ce, La, etc.) were coated by aerosol deposition. (The rare earth oxides accounted for 0.5-2.0 wt% of the total mass of the nano-ceramic coating (i.e., 0.5-2.0 mg of rare earth oxides were added per 100 mg Al2O3-SiO2 coating). The average particle size of the ceramic particles and rare earth oxides was 80 nm, the carrier gas pressure was 0.6 MPa, the deposition rate was 15 nm / min, and after coating, it was sintered at 350 °C for 20 minutes to form covalent bonds between the ceramic coating and the active sites on the conductor surface, resulting in a dense coating with a thickness of approximately 250 nm.

[0024] S2, Conductor stranding: First, single aluminum alloy wires are pre-twisted to form small stranded units. Then, multiple small stranded units are twisted a second time to form the final conductor structure. Figure 1 The aluminum alloy conductor 1 in the cable is used. By precisely controlling parameters such as the pitch, direction, and speed of pre-stretching and secondary stranding, the stranding tightness of the conductor is made more uniform, and the pitch consistency is higher. This significantly improves the conductivity and mechanical strength of the cable, and reduces the risk of conductor deformation and breakage during use.

[0025] S3, Insulation layer extrusion: Inner layer: Nano-ceramic filled insulation layer 2, which is made by mixing polyolefin insulation material with 6% silane-modified attapulgite nanoparticles and extruding it at 190°C through the first extruder, with the thickness controlled at 0.5mm; to improve insulation performance and weather resistance.

[0026] Middle layer: Semiconducting water-resistant layer 3, made of semiconducting polyolefin material containing 15% conductive carbon black, extruded at 200℃ through a second extruder, with a thickness controlled at 1.0mm; to achieve water resistance and uniform electric field distribution.

[0027] Outer layer: Weather-resistant insulation layer 4, made of 125℃ cross-linked halogen-free low-smoke flame-retardant polyolefin material, extruded at 210℃ through a third extruder, with a thickness controlled at 2.0mm; improves UV resistance, ozone resistance and high and low temperature resistance.

[0028] During the three-layer co-extrusion process, the traction speed is set to 8m / min, and the temperature of the composite die head is controlled at 200℃.

[0029] S4, Sheath: Weather-resistant sheath layer 5 After the insulation layer is extruded, a sheath is applied. The outer sheath is made of the same weather-resistant insulating material, extruded with a thickness controlled at 3mm; Finally, cross-linking treatment is performed to obtain the finished aluminum alloy photovoltaic cable.

[0030] Online detection and control are performed in step S3: During insulation extrusion, a combination of online crosslinking polarization measuring instrument and online infrared spectroscopy detection technology is incorporated into the aluminum alloy photovoltaic cable processing system for control. The online crosslinking polarization measuring instrument detects structural parameters such as wall thickness, eccentricity, ellipticity, and cable diameter of each layer online, acquiring high-frequency, real-time geometric morphology data of the insulation layer. The online infrared spectroscopy detection technology uses an infrared spectrometer with a wavelength range of 3-5μm to scan the compositional uniformity of the insulation layer at a frequency of 20 times per second. The detection data is transmitted to the intelligent control system in real time. Through big data and AI deep learning algorithms, the detection results are analyzed to extract and mine features, more accurately identifying potential problems and trends in insulation quality, and feeding this information back to the extruder host. The extruder's temperature, pressure, and traction speed are automatically adjusted to control the insulation thickness deviation within ±0.01mm. This multi-technology integrated online detection and real-time control method significantly improves the comprehensiveness and accuracy of insulation quality control compared to traditional single detection methods.

[0031] The cross-linked cable online tester is model X-RAY 8000 NXT, with a 100mm measuring range. The instrument includes the following configurations: a) ceramic window configuration, b) dual receiver configuration, c) 22-inch 8-point touch screen display and control system, and d) OPCProtocolincl.LAN communication port.

[0032] Online infrared detector: Spectral range: 5000-500cm⁻¹ Resolution: Better than 2cm-1 Beam splitter: Moisture-proof ZnSe Detectors: Room temperature DTGS; TE-MCT Communication interface: LAN Software: Allows setting continuous measurement and regular measurement modes. Detection modes: online monitoring mode and offline measurement mode.

[0033] The online cross-linked cable tester and online infrared detector have built-in AI models provided by the manufacturer. They extract and analyze the features of the detected data, make control decisions, and input them into the extruder host.

[0034] Comparative Example: Controlled Experiment To verify the effectiveness of the process of this invention, three sets of comparative experiments were set up: Group A: AA8030 aluminum alloy conductor without any surface treatment, using traditional single-layer insulation extrusion process; Group B: Only plasma treatment was performed; no nano-ceramic coating was applied. Group C: The "plasma activation-nano-ceramic coating" composite pretreatment process and three-layer co-extrusion process of this invention are adopted.

[0035] Experimental results:

Claims

1. A method for processing aluminum alloy photovoltaic cables, comprising the following steps: S1 Conductor pretreatment: The conductor is an aluminum alloy wire. First, the aluminum alloy wire is subjected to plasma activation treatment, and then an Al2O3-SiO2 nano-ceramic coating is coated on the surface. After coating, a sintering treatment is performed to form a dense protective layer. S2 conductor stranding: multiple aluminum alloy wires are stranded together to form a cable core; S3 Insulation Layer Extrusion: Preparation of a three-layer co-extrusion structure of nano-ceramic filled insulation layer-semi-conductive resistive water layer-weather resistant insulation layer; S4: Make a protective sheath.

2. The method for processing aluminum alloy photovoltaic cables according to claim 1, characterized in that... Step S1: The surface of the aluminum alloy conductor is subjected to plasma treatment for 30-60 seconds using an Ar / O2 mixed gas; an Al2O3-SiO2 nano-ceramic coating is coated on the activated conductor surface by aerosol deposition, with the carrier gas pressure controlled at 0.5-0.8MPa and the deposition rate at 10-20nm / min during the coating process; after coating, a low-temperature sintering treatment is performed, holding at 300-400℃ for 15-30 minutes to form a dense protective layer with a thickness of 200-300nm.

3. The method for processing aluminum alloy photovoltaic cables according to claim 2, characterized in that: The nano-ceramic coating contains trace amounts of rare earth element oxide nanoparticles, with the average particle size of the ceramic particles and rare earth oxides controlled at 50-100 nm.

4. The method for processing aluminum alloy photovoltaic cables according to claim 1, characterized in that... Step S2: First, pre-twist a single aluminum alloy wire to form a small twisted unit, and then twist multiple small twisted units a second time to form the final conductor structure.

5. The method for processing aluminum alloy photovoltaic cables according to claim 1, characterized in that... Step S3: The nano-ceramic filling insulation layer is made of polyolefin insulation material with 5-8% silane-modified attapulgite nanoparticles added; the semi-conductive resistive water layer is made of semi-conductive polyolefin material containing conductive carbon black; the weather-resistant insulation layer is made of halogen-free, low-smoke, flame-retardant cross-linked polyolefin material at 125℃.

6. The method for processing aluminum alloy photovoltaic cables according to claim 5, characterized in that: During the three-layer co-extrusion process, the extrusion temperature is controlled at 180-220℃ and the traction speed is 5-15m / min.

7. The method for processing aluminum alloy photovoltaic cables according to claim 1, characterized in that... Step S4: The sheath is extruded from halogen-free, low-smoke, flame-retardant cross-linked polyolefin material at 125℃.

8. The method for processing aluminum alloy photovoltaic cables according to claim 1, characterized in that... Step S3: During insulation extrusion, the wall thickness, eccentricity, ellipticity, and cable diameter of each layer are detected online. The geometric morphology data of the insulation layer is acquired in real time at high frequency. The detection data is transmitted to the intelligent control system in real time. Feature extraction and analysis are performed on the data to identify insulation quality problems and trends and feed them back to the extruder host. The temperature, pressure, and traction speed of the extruder are automatically adjusted to control the insulation thickness deviation within ±0.01mm.

9. An aluminum alloy photovoltaic cable processing system, comprising an extrusion unit, characterized in that: It includes an online crosslinking polarimeter, an infrared spectrometer, a data acquisition system, and an image processing system. The online crosslinking polarimeter and the infrared spectrometer are installed downstream of the extrusion unit to scan the extruded insulation layer in real time. The data acquisition system acquires spectral data at high speed and receives and processes sensor data from each unit. The image processing system analyzes the thickness and composition distribution of the insulation layer and adjusts the working status of the extrusion unit in real time based on preset process parameters.

10. The aluminum alloy photovoltaic cable processing system according to claim 9, characterized in that: During insulation extrusion, a combination of online crosslinking polarization measuring instrument and online infrared spectroscopy detection technology is used for control. The online crosslinking polarization measuring instrument detects the wall thickness, eccentricity, ellipticity, and cable diameter of each layer online, acquiring the geometric morphology data of the insulation layer in real time at high frequency. The online infrared spectroscopy detection technology uses an infrared spectrometer with a wavelength range of 3-5μm to scan the compositional uniformity of the insulation layer at a certain frequency. The detection data is transmitted to the intelligent control system in real time. Through data and algorithm analysis of the detection results, feature extraction and analysis are performed on the data to identify potential problems and trends in insulation layer quality, and feedback is given to the extruder host to automatically adjust the temperature, pressure, and traction speed of the extruder, controlling the insulation layer thickness deviation within ±0.01mm.

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