Temperature measurement type composite waterproof direct current cable for aluminum alloy core photovoltaic system

Abstract

The invention relates to the technical field of wires and cables, in particular to a composite waterproof direct-current cable for a temperature measurement type aluminum alloy core photovoltaic system, which comprises a double-layer galvanized steel tape armoring layer, a flame-retardant polyethylene outer protective layer arranged on the outer side of the double-layer galvanized steel tape armoring layer, and a polyethylene isolating layer arranged in the double-layer galvanized steel tape armoring layer. A cable core binding layer is installed in the polyethylene isolation layer, a temperature measurement optical fiber unit used for timely early warning when the cable is over-current and short-circuited, a direct current cable insulation layer and a six-class data transmission unit used for data transmission and system control are arranged in the cable core binding layer, and a direct current cable aluminum alloy core conductor is arranged in the direct current cable insulation layer; according to the invention, the composite waterproof DC cable structure can effectively reduce and even eliminate the probability of faults caused by moisture, water inflow, overcurrent and short circuit of the cable, and has the advantages of low material consumption, low manufacturing cost, high system operation safety and the like.

Description

Technical Field

[0001] The invention relates to the technical field of electric wires and cables, in particular to a temperature-measuring aluminum alloy core composite waterproof DC cable for a photovoltaic system. Background Art

[0002] Temperature-sensing aluminum alloy core composite waterproof DC cable for photovoltaic systems, used for electrical line connection between combiner box and inverter; The traditional photovoltaic power generation system cable process structure usually uses copper conductor twisting, extruded cross-linked polyethylene insulation, extruded polyvinyl chloride isolation layer after cabling, double-layer galvanized steel belt armor, and the sheath is usually made of flame-retardant polyethylene material; This type of cable has the disadvantages of high cost, poor waterproof performance, and inability to timely monitor abnormal temperature rise during cable operation. When an overcurrent or short circuit occurs in the terminal or the cable itself, it is very easy to cause the cable and electrical facilities to catch fire, resulting in large direct and indirect economic losses. At the same time, due to high humidity or continuous rainfall, the waterproof performance of the polyvinyl chloride material used in the cable is poor, which can easily lead to a decrease in the insulation resistance of the cable, causing power generation system operation failures, affecting power generation efficiency, and causing great losses. Therefore, in order to solve the above problems, a temperature measuring aluminum alloy core composite waterproof DC cable for photovoltaic system is proposed. Summary of the invention

[0003] The purpose of the present invention is to provide a temperature-measuring aluminum alloy core composite waterproof DC cable for photovoltaic systems, so as to solve the shortcomings of existing cables such as high cost, poor waterproofness, and inability to timely monitor abnormal temperature rise during cable operation. When an overcurrent or short circuit fault occurs in the terminal or the cable itself, it is very easy to cause the cable and electrical facilities to catch fire, resulting in large direct and indirect economic losses. At the same time, due to high environmental humidity or continuous rainfall, the waterproof performance of the polyvinyl chloride material used in the cable is poor, which can easily lead to a decrease in the insulation resistance of the cable, causing failure of the power generation system, affecting the power generation efficiency, and causing great losses.

[0004] To achieve the above object, the present invention provides the following technical solutions: A temperature-measuring aluminum alloy core composite waterproof DC cable for photovoltaic systems, comprising a double-layer galvanized steel belt armor layer, a flame-retardant polyethylene outer sheath is installed on the outer side of the double-layer galvanized steel belt armor layer, a polyethylene isolation layer is arranged inside the double-layer galvanized steel belt armor layer, a cable core wrapping layer is arranged inside the polyethylene isolation layer, a temperature-measuring optical fiber unit for timely warning when the cable is over-current or short-circuited, a DC cable insulation layer and a Category 6 data transmission unit for data transmission and system control are arranged inside the cable core wrapping layer, and a DC cable aluminum alloy core conductor is arranged inside the DC cable insulation layer; The DC cable aluminum alloy core conductor is made by adding corresponding proportions of Si, Fe, Cu, Mn, Mg, Cr, Ni, Zn, Ti, B, and Be chemical components, and the DC cable aluminum alloy core conductor is made through drawing, twisting, and annealing processes.

[0005] As a further optimization of the present invention, the six types of data transmission units adopt a double-layer shielding structure.

[0006] As a further optimization of the present invention, the tensile strength of the aluminum alloy core conductor of the DC cable is 98-159 N / mm 2 The elongation at break of the aluminum alloy core conductor of the DC cable is not less than 10%.

[0007] As a further optimization of the present invention, a plurality of grooves are provided on the inner side of the upper end of the flame-retardant polyethylene outer protective layer, and absorbent cotton is installed inside the grooves.

[0008] As a further optimization of the present invention, there are a plurality of grooves and absorbent cottons, and the grooves and absorbent cottons correspond one to one, and the absorbent cottons are arranged in an arc shape.

[0009] As a further optimized content of the present invention, the six types of data transmission units include a transmitting end, a receiving end, and a clock synchronization module for dynamically adjusting the coefficient to correct the clock frequency of the receiving end according to the timestamp difference between the receiving end and the transmitting end, and the adjustment steps of the clock synchronization module are: S1: Get the timestamps of the sender and receiver; S2: Calculate the difference between the sending and receiving timestamps ; S3: Dynamically adjust the clock frequency of the receiving end to correct the clock frequency of the receiving end. The correction calculation formula is:

[0010] In the formula, f r ′ is the corrected receiving end clock frequency, f r is the current receiving end clock frequency, t r is the receiving end timestamp, t s is the timestamp of the sender, α 0 is the initial adjustment coefficient, γ is the exponential decay rate parameter, is an exponential decay term, (t r -t s ) is the timestamp difference between the receiving end and the sending end; S4: Continuously monitor the timestamp difference and perform correction operations cyclically until synchronization is completed.

[0011] As a further optimization of the present invention, the clock synchronization module performs a time stamp difference Dynamic monitoring is performed and the adjustment coefficient is calculated in real time to ensure that efficient synchronization accuracy is maintained even when the clock frequencies of the transmitter and receiver fluctuate slightly.

[0012] As a further optimized content of the present invention, wherein: the initial adjustment coefficient It is dynamically adjusted according to the historical error of the clock frequency of the transmitter and the receiver to adapt to different transmission environments and further improve the synchronization stability of the system. The adjustment algorithm includes the weighted average calculation of historical clock deviations, the initial adjustment coefficient It is generated by analyzing previous transmission data and clock deviation history.

[0013] As a further optimization of the present invention, the exponential decay rate parameter γ is adaptively adjusted according to the distance between the receiving end and the sending end, the transmission delay and the network stability, so as to ensure the flexibility and robustness of the system in maintaining clock synchronization under different network conditions.

[0014] Compared with the prior art, the present invention has the following beneficial effects: 1. In the present invention, the composite waterproof DC cable structure can effectively reduce or even eliminate the failure probability of the cable due to moisture ingress, overcurrent, and short circuit, and has the advantages of less material consumption, low manufacturing cost, and high system operation safety. At the same time, the temperature rise of the cable can be monitored in time during the operation of the cable. If the cable or electrical system is overcurrent or short circuited, it can give a timely warning, which plays a good line protection role. In addition, data transmission and system control can be concentrated inside the cable. The data transmission unit is provided with a double-layer shielding structure to ensure that the transmission signal will not be interfered by external electromagnetic signals, thereby ensuring data transmission safety; 2. In the present invention, a flame-retardant polyethylene is used as the isolation layer and outer sheath of the cable. Since polyethylene has excellent waterproof performance, it can effectively play a waterproof role for a long time. At the same time, it has good acid and alkali resistance and aging resistance, which can ensure the long-term stable operation of the cable; 3. In the present invention, by introducing the clock correction formula of the dynamic adjustment coefficient and the exponential decay term, the problem of data transmission synchronization failure caused by the inconsistent clock frequencies of the sending and receiving ends can be effectively solved. The system maintains a high degree of synchronization accuracy during long-term data transmission, and is particularly suitable for complex network environments. Its beneficial effects are reflected in the following aspects: First, through the design of the dynamic adjustment coefficient and the exponential decay, the adaptability of the clock synchronization is guaranteed, and it can adapt to different transmission environments and clock frequency fluctuations; secondly, the weighted average algorithm of the historical clock deviation improves the smoothness and continuity of the correction, and avoids the interference of frequent jumps on data transmission; finally, the system also has an error tolerance and forced correction mechanism, which can quickly respond to the situation of excessive clock deviation and ensure the continuity and stability of data transmission. These characteristics jointly improve the reliability of data transmission, especially in the scenarios of long-term transmission and high-frequency synchronization correction. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the overall structure of the present invention; Figure 2 It is a schematic diagram of the groove opening position structure of the present invention.

[0016] In the figure: 1. Temperature measuring optical fiber unit; 2. DC cable insulation layer; 3. DC cable aluminum alloy core conductor; 4. Cable core wrapping layer; 5. Polyethylene isolation layer; 6. Double-layer galvanized steel belt armor layer; 7. Flame-retardant polyethylene outer sheath; 8. Category 6 data transmission unit; 9. Groove; 10. Water-absorbent cotton. DETAILED DESCRIPTION

[0017] See also Figure 1-2 , the present invention provides a technical solution: A temperature-measuring aluminum alloy core composite waterproof DC cable for photovoltaic systems, comprising a double-layer galvanized steel belt armor layer 6, a flame-retardant polyethylene outer sheath 7 is installed on the outer side of the double-layer galvanized steel belt armor layer 6, a polyethylene isolation layer 5 is arranged inside the double-layer galvanized steel belt armor layer 6, a cable core wrapping layer 4 is installed inside the polyethylene isolation layer 5, a temperature-measuring optical fiber unit 1 for timely warning when the cable is overcurrent or short-circuited, a DC cable insulation layer 2 and a Category 6 data transmission unit 8 for data transmission and system control are arranged inside the cable core wrapping layer 4, a DC cable insulation layer 2 is arranged inside the DC cable insulation layer 2; the DC cable aluminum alloy core conductor 3 is made by adding corresponding proportions of Si, Fe, Cu, Mn, Mg, Cr, Ni, Zn, Ti, B, and Be chemical components, and the DC cable aluminum alloy core conductor 3 is made by drawing, twisting, and annealing processes.

[0018] As a technical solution for further implementation of this scheme, the six-category data transmission unit 8 adopts a double-layer shielding structure. By setting the double-layer shielding structure, it is ensured that the transmission signal will not be interfered by external electromagnetic signals, thereby ensuring data transmission security; As a technical solution for further implementation of this solution, the tensile strength of the DC cable aluminum alloy core conductor 3 is 98-159N / mm 2 The elongation at break of the aluminum alloy core conductor 3 of the DC cable is not less than 10%, which can ensure the tensile strength of the aluminum alloy core conductor 3 of the DC cable; As a technical solution for further implementation of this scheme, a plurality of grooves 9 are provided on the inner side of the upper end of the flame-retardant polyethylene outer sheath 7, and absorbent cotton 10 is installed inside the groove 9. A plurality of grooves 9 and absorbent cotton 10 are provided, and there is a one-to-one correspondence between the grooves 9 and the absorbent cotton 10. The absorbent cotton 10 is arranged in an arc shape. Through the above arrangement, when the cable is installed outdoors and used in warm areas with more rain, the absorbent cotton 10 can be used to collect rainwater, and after the rain stops, the cable is cooled by evaporating the rainwater inside the absorbent cotton 10, so as to improve the stability of the cable during operation; As a technical solution for further implementing this solution, the six-category data transmission unit 8 includes a transmitting end, a receiving end, and a clock synchronization module for dynamically adjusting the coefficient to correct the clock frequency of the receiving end according to the timestamp difference between the receiving end and the transmitting end. The adjustment steps of the clock synchronization module are: S1: Get the timestamps of the sender and receiver; S2: Calculate the difference between the sending and receiving timestamps ; S3: Dynamically adjust the clock frequency of the receiving end to correct the clock frequency of the receiving end. The correction calculation formula is:

[0019] In the formula, f r ′ is the corrected receiving end clock frequency, f r is the current receiving end clock frequency, t r is the receiving end timestamp, t s is the timestamp of the sender, α 0 is the initial adjustment coefficient, γ is the exponential decay rate parameter, is an exponential decay term, (t r -t s ) is the timestamp difference between the receiving end and the sending end; S4: Continuously monitor the timestamp difference and perform correction operations cyclically until synchronization is completed. This method provides an automated and continuous clock correction process, ensuring that the system maintains high-precision synchronization during long-term transmission and reducing data transmission failures caused by inconsistent clock frequencies. As a technical solution for further implementing this solution, the clock synchronization module calculates the timestamp difference |t r -t s | Perform dynamic monitoring and calculate the adjustment coefficient in real time to ensure that efficient synchronization accuracy can be maintained even when the clock frequency of the sender and receiver fluctuates slightly. By dynamically monitoring the timestamp difference, the synchronization failure problem caused by frequency fluctuation can be reduced, especially in the process of long-term data transmission, the synchronization stability is improved; As a technical solution for further implementation of this scheme, the initial adjustment coefficient α 0 It is dynamically adjusted according to the historical error of the clock frequency of the transmitter and the receiver to adapt to different transmission environments and further improve the synchronization stability of the system. The adjustment coefficient α 0 The adjustment algorithm includes the weighted average calculation of historical clock deviations, and the initial adjustment coefficient α 0 It is generated by analyzing previous transmission data and clock deviation history. The analysis of historical records can help determine the correction force more accurately and improve the efficiency and accuracy of clock synchronization. As a technical solution for further implementation of this solution, the exponential decay rate parameter γ is adaptively adjusted according to the distance between the receiving end and the sending end, the transmission delay and the network stability, ensuring the flexibility and robustness of the system in maintaining clock synchronization under different network conditions. By considering the physical distance and network delay, the algorithm can be adaptively adjusted to reduce synchronization failures caused by different network conditions and ensure the stability of data transmission. When the clock difference is too large, the system can respond quickly, avoid data transmission interruption or serious errors by accelerating synchronization, and improve the robustness of the system.

[0020] Workflow: In the actual application process of the composite waterproof DC cable, the chemical components of Si, Fe, Cu, Mn, Mg, Cr, Ni, Zn, Ti, B, and Be added to the aluminum alloy core conductor 3 of the DC cable, as well as the production process of drawing, twisting, and annealing, can make it have excellent creep resistance and conductivity, and good mechanical properties such as bending and tensile strength, elongation at break, and the weight of the cable is only 40-60% of the same type of copper core cable. At the same time, the temperature measuring optical fiber unit 1 can timely monitor the temperature rise of the cable during the operation of the cable. If the cable or electrical system is overcurrent or short-circuited, it can give a timely warning, which can play a good role in line protection. At the same time, through the six-category data transmission unit 8, during the operation of the cable, data can be transmitted. At the same time, the double-layer shielding structure set by the data transmission unit can ensure that the transmission signal will not be interfered by external electromagnetic signals, ensuring data transmission safety. In addition, the flame-retardant polyethylene is used as the isolation layer and outer sheath of the cable, so that the cable has excellent waterproof performance, which can effectively play a waterproof role for a long time. At the same time, it has good acid and alkali resistance and aging resistance, which can ensure the long-term stable operation of the cable. At the same time, during the use of the cable, the use of the transmitter, receiver and clock synchronization module can automate and continuously correct the clock process, ensuring that the system maintains high-precision synchronization during long-term transmission and reducing the occurrence of data transmission failures due to inconsistent clock frequencies.

[0021] This article uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. The above is only a preferred implementation of the present invention. It should be pointed out that due to the limitations of textual expression and the objective existence of infinite specific structures, ordinary technicians in this technical field can make several improvements, modifications or changes without departing from the principles of the present invention, and can also combine the above technical features in an appropriate manner; these improvements, modifications, changes or combinations, or the direct application of the inventive concept and technical solution to other occasions without improvement, should be regarded as the protection scope of the present invention.

Claims

1. A temperature-measuring aluminum alloy core composite waterproof DC cable for photovoltaic systems, comprising a double-layer galvanized steel belt armor layer (6), characterized in that: A flame-retardant polyethylene outer sheath (7) is installed on the outside of the double-layer galvanized steel belt armor layer (6), a polyethylene isolation layer (5) is provided inside the double-layer galvanized steel belt armor layer (6), a cable core wrapping layer (4) is installed inside the polyethylene isolation layer (5), a temperature measuring optical fiber unit (1) for timely warning when the cable is over-current or short-circuited, a DC cable insulation layer (2) and a Category 6 data transmission unit (8) for data transmission and system control are provided inside the cable core wrapping layer (4), and a DC cable aluminum alloy core conductor (3) is provided inside the DC cable insulation layer (2); The DC cable aluminum alloy core conductor (3) is manufactured by adding chemical components of Si, Fe, Cu, Mn, Mg, Cr, Ni, Zn, Ti, B and Be in corresponding proportions, and the DC cable aluminum alloy core conductor (3) is manufactured through drawing, twisting and annealing processes.

2. A temperature-measuring aluminum alloy core composite waterproof DC cable for photovoltaic systems according to claim 1, characterized in that: The six types of data transmission units (8) adopt a double-layer shielding structure.

3. The temperature-measuring aluminum alloy core composite waterproof DC cable for photovoltaic system according to claim 1, characterized in that: The DC cable aluminum alloy core conductor (3) has a tensile strength of 98-159 N / mm 2 The aluminum alloy core conductor (3) of the DC cable has an elongation at break of not less than 10%.

4. The temperature-measuring aluminum alloy core composite waterproof DC cable for photovoltaic system according to claim 1, characterized in that: A plurality of grooves (9) are provided on the inner side of the upper end of the flame-retardant polyethylene outer protective layer (7), and absorbent cotton (10) is installed inside the grooves (9).

5. The temperature-measuring aluminum alloy core composite waterproof DC cable for photovoltaic system according to claim 1, characterized in that: A plurality of the grooves (9) and the absorbent cotton (10) are provided, and the grooves (9) and the absorbent cotton (10) correspond to each other one by one. The absorbent cotton (10) is arranged in an arc shape.

6. The temperature-measuring aluminum alloy core composite waterproof DC cable for photovoltaic system according to claim 1, characterized in that: The six types of data transmission units (8) include a transmitting end, a receiving end, and a clock synchronization module for dynamically adjusting a coefficient to correct a clock frequency of the receiving end according to a time stamp difference between the receiving end and the transmitting end. The adjustment steps of the clock synchronization module are as follows: S1: Get the timestamps of the sender and receiver; S2: Calculate the difference between the sending and receiving timestamps t r -t s ; S3: Dynamically adjust the clock frequency of the receiving end to correct the clock frequency of the receiving end. The correction calculation formula is: In the formula, f r ′ is the corrected receiving end clock frequency, f r is the current receiving end clock frequency, t r is the receiving end timestamp, t s is the timestamp of the sending end, α0 is the initial adjustment coefficient, γ is the exponential decay rate parameter, is an exponential decay term, (t r -t s ) is the timestamp difference between the receiving end and the sending end; S4: Continuously monitor the timestamp difference and perform correction operations cyclically until synchronization is completed.

7. A temperature-measuring aluminum alloy core composite waterproof DC cable for photovoltaic systems according to claim 6, characterized in that: The clock synchronization module calculates the timestamp difference Dynamic monitoring is performed and the adjustment coefficient is calculated in real time to ensure that efficient synchronization accuracy is maintained even when the clock frequencies of the transmitter and receiver fluctuate slightly.

8. The temperature-measuring aluminum alloy core composite waterproof DC cable for photovoltaic system according to claim 6, characterized in that: The initial adjustment coefficient is dynamically adjusted according to the historical errors of the clock frequencies of the transmitting and receiving ends to adapt to different transmission environments and further improve the synchronization stability of the system. The adjustment algorithm of the adjustment coefficient includes a weighted average calculation of the historical clock deviation. The initial adjustment coefficient is generated by analyzing previous transmission data and clock deviation historical records.

9. The temperature-measuring aluminum alloy core composite waterproof DC cable for photovoltaic system according to claim 6, characterized in that: The exponential decay rate parameter γ is adaptively adjusted according to the distance between the receiving end and the sending end, the transmission delay and the network stability, so as to ensure the flexibility and robustness of the system in maintaining clock synchronization under different network conditions.

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