A method and device for arranging power cables based on optimal current carrying capacity

Abstract

The present invention provides a method and device for arranging power cables based on optimal current carrying capacity, and relates to the technical field of current carrying capacity control of power cables, including: obtaining hole positions of power conduits and cable laying information; generating a hole position acquisition characterization sequence and the cable current carrying capacity under the characterization sequence based on the hole positions of the power conduits and the cable laying information, and obtaining the characterization sequence under the maximum cable current carrying capacity. The method and device provided by the present invention can determine the heat consumed by each cable and the influence of external factors on the cable current carrying capacity, determine the layout mode with the maximum total current carrying capacity of the cable, and improve the reliability of power grid operation.

Description

Technical Field

[0001] The present invention relates to the technical field of current carrying capacity control of power cables, and in particular to a method and device for arranging power cables based on optimal current carrying capacity. Background Art

[0002] As the size of cities in my country continues to expand, electricity consumption and load in various regions are increasing year by year, which places higher and higher demands on the power transmission capacity of power equipment. Especially in the peak summer period, the load side of the power system reaches the peak of electricity consumption, and some cable lines are often overloaded or even fully loaded, which brings huge challenges to the reliable operation of the power grid.

[0003] The current carrying capacity is a performance parameter related to the transmission capacity of power cables. Under certain conditions of use, when the current flowing through the power cable conductor generates heat in various parts of the cable, it can be dissipated to the surrounding medium in a timely manner, so that the temperature of the insulation layer does not exceed the long-term maximum allowable operating temperature. The current carrying capacity of the cable is the maximum current allowed to flow through the cable conductor at the maximum allowable operating temperature.

[0004] When the cable is in operation, the heat generated by the loss of each part of the cable and the influence of external factors will cause the operating temperature of the cable to change. If the operating temperature of the cable is too high, it will accelerate the aging of the insulation and shorten the service life of the cable. The main factors affecting the current carrying capacity of the cable include the material of the conductor, the material of the cable insulation, the temperature of the surrounding medium, the thermal resistance of the surrounding medium, etc. These factors will change with different types of cables under different operating conditions.

[0005] In large and medium-sized cities, more and more 10kV and above cables are laid in power pipes, which can effectively improve the utilization rate of cable channels. More than a dozen cables can be laid in the same channel. However, in actual work, several holes are often reserved in the power pipe channel to facilitate future maintenance work. Therefore, there are many ways to arrange power cables in the pipe channel. Because of the different effects of mutual heating, each arrangement corresponds to a specific cable current carrying capacity. Therefore, how to optimally configure the arrangement of power cables in the pipe to ensure that the total current carrying capacity of the cables is maximized is a question worth exploring.

[0006] In summary, in the prior art, how to determine the heat consumed by each cable and the impact of external factors on the cable current carrying capacity, determine the layout method with the maximum total current carrying capacity of the cable, and improve the reliability of power grid operation are issues that need to be solved urgently. Summary of the invention

[0007] In view of this, the purpose of the present invention is to provide a method for arranging power cables based on optimal current carrying capacity, so as to determine the heat consumed by each cable and the influence of external factors on the current carrying capacity of the cables, determine the layout mode with the maximum total current carrying capacity of the cables, and improve the reliability of power grid operation.

[0008] The present invention provides a method for arranging power cables based on optimal current carrying capacity, comprising:

[0009] Obtain the location of power pipe holes and cable laying information;

[0010] Based on the hole positions of the power conduit and the cable laying information, a hole position acquisition characterization sequence and a cable current carrying capacity under the characterization sequence are generated to obtain the characterization sequence under the maximum cable current carrying capacity.

[0011] Preferably, the step of generating a hole position acquisition characterization sequence and a cable current carrying capacity under the characterization sequence based on the hole position of the power pipe and the cable laying information, and acquiring the characterization sequence under the maximum cable current carrying capacity comprises:

[0012] Set i=1 and the number of iterations, the hole positions of the power pipes and the cable laying information generate the hole positions to obtain the parent generation feature sequence;

[0013] Determine whether i is less than the number of iterations;

[0014] If yes, performing cloning transformation and mutation transformation on the parental characteristic sequence to generate a child characteristic sequence;

[0015] Obtaining the cable ampacities of all the child-generation characteristic sequences to obtain an optimal child-generation characteristic sequence, and obtaining the cable ampacities of all the parent-generation characteristic sequences to obtain an optimal parent-generation characteristic sequence;

[0016] Let i=i+1, randomly generate an external population, the external population is different from the optimal parent feature sequence, and the optimal child feature sequence, the optimal child feature sequence, the obtaining of the optimal parent feature sequence, the external population generates a first sequence, and the step of determining whether i is less than the number of iterations.

[0017] Preferably, the step of determining whether i is less than the number of iterations comprises:

[0018] If not, the iteration is stopped, and the cable current carrying capacity of all the parent characteristic sequences is obtained to obtain the cable current carrying capacity.

[0019] Preferably, the step of performing cloning transformation and mutation transformation on the parental characteristic sequence to generate the offspring characteristic sequence comprises:

[0020] Two numbered positions in the parental eigenvalue sequence are permuted to perform a clonal permutation of the parental eigenvalue sequence.

[0021] Preferably, the step of performing cloning transformation and mutation transformation on the parental characteristic sequence to generate the offspring characteristic sequence comprises:

[0022] The four numbered positions in the parental eigenvalue sequence are reversed to perform a variation transformation on the parental eigenvalue sequence.

[0023] Preferably, the cable current carrying capacity is obtained using the following formula:

[0024]

[0025] λ1—sheath loss coefficient, that is, the ratio of sheath loss to total core loss;

[0026] λ2—armor loss coefficient, that is, the ratio of armor loss to total core loss;

[0027] R—wire core AC resistance value (Ω / m);

[0028] W d — dielectric loss (in watts per meter);

[0029] N—the number of cores in the cable;

[0030] T1—Thermal resistance of the insulation layer (measured in Kelvin per watt);

[0031] T2—Thermal resistance of the armor layer (measured in Kelvin per watt);

[0032] T3—Thermal resistance of the outer sheath (measured in Kelvin per watt);

[0033] T4—Thermal resistance of the medium surrounding the cable (Kelvin meter per watt);

[0034] θ max —The maximum temperature allowed for the cable core;

[0035] θ amb —Ambient temperature of the cable;

[0036] Δθ max =θ max -θ amb ;

[0037] Δθ int —The reduction in core temperature due to heating of adjacent cables.

[0038] In another aspect, the present invention provides a power cable arrangement device based on optimal current carrying capacity, comprising:

[0039] Information acquisition module: used to obtain the hole position of power pipes and cable laying information;

[0040] Characterization sequence acquisition module: used to generate a hole position acquisition characterization sequence and the cable current carrying capacity under the characterization sequence based on the power conduit hole position and cable laying information, and to obtain the characterization sequence under the maximum cable current carrying capacity.

[0041] The embodiments of the present invention bring the following beneficial effects: The present invention provides a method and device for arranging power cables based on optimal current carrying capacity, including: obtaining power conduit hole positions and cable laying information; generating a hole position acquisition characterization sequence and the cable current carrying capacity under the characterization sequence based on the power conduit hole positions and cable laying information, and obtaining the characterization sequence under the maximum cable current carrying capacity. The method and device provided by the present invention can determine the heat consumed by each cable and the influence of external factors on the cable current carrying capacity, determine the layout method with the maximum total current carrying capacity of the cable, and improve the reliability of power grid operation.

[0042] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention are realized and obtained by the structures particularly pointed out in the description, claims and drawings.

[0043] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0045] Figure 1 A flow chart of a method for arranging power cables based on optimal current carrying capacity provided by an embodiment of the present invention;

[0046] Figure 2 A schematic diagram of a characterization sequence of a power cable arrangement method based on optimal current carrying capacity provided by an embodiment of the present invention;

[0047] Figure 3 A schematic diagram of cloning transformation of a power cable arrangement method based on optimal current carrying capacity provided by an embodiment of the present invention;

[0048] Figure 4 A schematic diagram of a variation transformation of a power cable arrangement method based on optimal current carrying capacity provided by an embodiment of the present invention;

[0049] Figure 5A flow chart of another method for arranging power cables based on optimal current carrying capacity provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0050] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0051] At present, several holes are often reserved in the power pipe channel to facilitate future maintenance work. Therefore, there are multiple arrangements of power cables in the pipe channel. Because of the different effects of mutual heating, each arrangement corresponds to a specific cable current carrying capacity. Therefore, how to optimally configure the arrangement of power cables in the pipe to ensure that the total current carrying capacity of the cables is maximized is a problem worth exploring. Based on this, an embodiment of the present invention provides a method and device for arranging power cables based on optimal current carrying capacity to determine the heat consumed by each cable and the influence of external factors on the current carrying capacity of the cables, determine the layout method with the maximum total current carrying capacity of the cables, and improve the reliability of power grid operation.

[0052] To facilitate understanding of this embodiment, a method for arranging power cables based on optimal current carrying capacity disclosed in an embodiment of the present invention is first introduced in detail.

[0053] Embodiment 1:

[0054] like Figure 1 As shown, the present invention provides a method for arranging power cables based on optimal current carrying capacity, comprising:

[0055] Obtain the location of power pipe holes and cable laying information;

[0056] In the embodiment provided by the present invention, according to the given power pipe hole positions and cable laying information, taking a 3×5-hole pipe channel in Tianjin as an example, the construction department plans to lay 12 35kV cables in the channel (actually 6 circuits, each with double cables), and accordingly encodes the 15 hole positions in sequence, and obtains the corresponding characterization sequence, such as Figure 2 shown.

[0057] Based on the hole positions of the power conduit and the cable laying information, a hole position acquisition characterization sequence and a cable current carrying capacity under the characterization sequence are generated to obtain the characterization sequence under the maximum cable current carrying capacity.

[0058] like Figure 5As shown, preferably, the step of generating a hole position acquisition characterization sequence and a cable current carrying capacity under the characterization sequence based on the hole position of the power pipe and the cable laying information, and acquiring the characterization sequence under the maximum cable current carrying capacity includes:

[0059] Set i=1 and the number of iterations, the hole positions of the power pipes and the cable laying information generate the hole positions to obtain the parent generation feature sequence;

[0060] In the embodiment provided by the present invention, two sequences are randomly generated as initial parental characteristic sequences;

[0061] Determine whether i is less than the number of iterations;

[0062] If yes, performing cloning transformation and mutation transformation on the parental characteristic sequence to generate a child characteristic sequence;

[0063] Obtaining the cable ampacities of all the child-generation characteristic sequences to obtain an optimal child-generation characteristic sequence, and obtaining the cable ampacities of all the parent-generation characteristic sequences to obtain an optimal parent-generation characteristic sequence;

[0064] Let i=i+1, randomly generate an external population, the external population is different from the optimal parent feature sequence, and the optimal child feature sequence, the optimal child feature sequence, the obtaining of the optimal parent feature sequence, the external population generates a first sequence, the parent feature sequence is updated to the first sequence, and the step of determining whether i is less than the number of iterations is performed.

[0065] Preferably, the step of determining whether i is less than the number of iterations comprises:

[0066] If not, the iteration is stopped, and the cable current carrying capacity of all the parent characteristic sequences is obtained to obtain the cable current carrying capacity.

[0067] As can be seen from the above, obtaining the characteristic sequence of the offspring through the characteristic sequence of the parent can be achieved through cloning transformation and mutation transformation;

[0068] Further, such as Figure 3 As shown, two numbered positions in the parental characteristic sequence are transformed to clone the parental characteristic sequence.

[0069] Furthermore, the four numbered positions in the parental characteristic sequence are arranged in reverse order to mutate the parental characteristic sequence.

[0070] In the embodiment provided by the present invention, the number of parent characteristic sequences is set to 10, 10 child characteristic sequences are obtained through cloning transformation, 10 child characteristic sequences are obtained through mutation transformation, the cable current carrying capacity of each parent characteristic sequence is obtained to obtain the optimal parent characteristic sequence, the cable current carrying capacity of each child characteristic sequence is obtained to obtain the optimal child characteristic sequence, and 8 external populations that are different from both the parent characteristic sequence and the optimal child characteristic sequence are randomly generated. The external population, the optimal parent characteristic sequence, and the optimal child characteristic sequence together constitute a first sequence and participate in the cycle as a new parent characteristic sequence.

[0071] Preferably, the cable current carrying capacity is obtained using the following formula:

[0072]

[0073] λ1—sheath loss coefficient, that is, the ratio of sheath loss to total core loss;

[0074] λ2—armor loss coefficient, that is, the ratio of armor loss to total core loss;

[0075] R—wire core AC resistance value (Ω / m);

[0076] W d — dielectric loss (in watts per meter);

[0077] N—the number of cores in the cable;

[0078] T1—Thermal resistance of the insulation layer (measured in Kelvin per watt);

[0079] T2—Thermal resistance of the armor layer (measured in Kelvin per watt);

[0080] T3—Thermal resistance of the outer sheath (measured in Kelvin per watt);

[0081] T4—Thermal resistance of the medium surrounding the cable (Kelvin meter per watt);

[0082] θ max —The maximum temperature allowed for the cable core;

[0083] θ amb —Ambient temperature of the cable;

[0084] Δθ max =θ max -θ amb ;

[0085] Δθ int —The reduction in core temperature due to heating of adjacent cables.

[0086] On the other hand, the present invention provides a power cable arrangement device based on optimal current carrying capacity, comprising:

[0087] Information acquisition module: used to obtain the hole position of power pipes and cable laying information;

[0088] Characterization sequence acquisition module: used to generate a hole position acquisition characterization sequence and the cable current carrying capacity under the characterization sequence based on the power conduit hole position and cable laying information, and to obtain the characterization sequence under the maximum cable current carrying capacity.

[0089] Unless otherwise specifically stated, the relative steps, numerical expressions and values ​​of the components and steps set forth in these embodiments do not limit the scope of the present invention.

[0090] The flow charts and block diagrams in the accompanying drawings show the possible architecture, functions and operations of the system, method and computer program product according to multiple embodiments of the present invention. In this regard, each box in the flow chart or block diagram can represent a module, a program segment or a part of a code, and the module, a program segment or a part of a code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a different order from the order marked in the accompanying drawings. For example, two consecutive boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram and / or flow chart, and the combination of the boxes in the block diagram and / or flow chart can be implemented with a dedicated hardware-based system that performs a specified function or action, or can be implemented with a combination of dedicated hardware and computer instructions.

[0091] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working process of the system and device described above can refer to the corresponding process in the aforementioned method embodiment, and will not be repeated here.

[0092] In addition, in the description of the embodiments of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0093] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0094] Finally, it should be noted that the above-described embodiments are only specific implementations of the present invention, which are used to illustrate the technical solutions of the present invention, rather than to limit them. The protection scope of the present invention is not limited thereto. Although the present invention is described in detail with reference to the above-described embodiments, ordinary technicians in the field should understand that any technician familiar with the technical field can still modify the technical solutions recorded in the above-described embodiments within the technical scope disclosed by the present invention, or can easily think of changes, or make equivalent replacements for some of the technical features therein; and these modifications, changes or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A method for arranging power cables based on optimal current carrying capacity, characterized in that: include: Obtain the location of power pipe holes and cable laying information; Based on the hole positions of the power pipes and the cable laying information, a hole position acquisition characterization sequence and a cable current carrying capacity under the characterization sequence are generated, and a characterization sequence under the maximum cable current carrying capacity is obtained, specifically, Set i=1 and the number of iterations, the hole positions of the power pipes and the cable laying information generate the hole positions to obtain the parent generation feature sequence; Determine whether i is less than the number of iterations; If yes, performing cloning transformation and mutation transformation on the parental characteristic sequence to generate a child characteristic sequence; Obtaining the cable ampacities of all the child-generation characteristic sequences to obtain an optimal child-generation characteristic sequence, and obtaining the cable ampacities of all the parent-generation characteristic sequences to obtain an optimal parent-generation characteristic sequence; Let i=i+1, randomly generate an external population, the external population is different from the optimal parent feature sequence and the optimal parent feature sequence, the optimal child feature sequence, the obtained optimal parent feature sequence, and the external population together constitute a first sequence, let the parent feature sequence be updated to the first sequence, and perform the step of determining whether i is less than the number of iterations; If not, the iteration is stopped, and the cable current carrying capacity of all the parent characteristic sequences is obtained to obtain the cable current carrying capacity.

2. The method according to claim 1, characterized in that The step of performing cloning transformation and mutation transformation on the parental characteristic sequence to generate the offspring characteristic sequence comprises: Two numbered positions in the parental eigenvalue sequence are permuted to perform a clonal permutation of the parental eigenvalue sequence.

3. The method according to claim 1, characterized in that The step of performing cloning transformation and mutation transformation on the parental characteristic sequence to generate the offspring characteristic sequence comprises: The four numbered positions in the parental eigenvalue sequence are reversed to perform a variation transformation on the parental eigenvalue sequence.

4. The method according to any one of claims 1 to 2, characterized in that: Use the following formula to obtain the cable current carrying capacity: λ1—sheath loss coefficient, that is, the ratio of sheath loss to total core loss; λ2—armor loss coefficient, that is, the ratio of armor loss to total core loss; R—wire core AC resistance value (Ω / m); W d — dielectric loss (in watts per meter); N—the number of cores in the cable; T1—Thermal resistance of the insulation layer (measured in Kelvin per watt); T2—Thermal resistance of the armor layer (measured in Kelvin per watt); T3—Thermal resistance of the outer sheath (measured in Kelvin per watt); T4—Thermal resistance of the medium surrounding the cable (Kelvin meter per watt); θ max —The maximum temperature allowed for the cable core; θ amb —Ambient temperature of the cable; Vth max =θ max -θ amb ; Vθ int —The reduction in core temperature due to heating of adjacent cables.

5. A power cable arrangement device based on optimal current carrying capacity, characterized in that: include: Information acquisition module: used to obtain the hole position of power pipes and cable laying information; A characterization sequence acquisition module is used to generate a hole position acquisition characterization sequence and a cable current carrying capacity under the characterization sequence based on the hole position of the power pipe and the cable laying information, and to obtain a characterization sequence under the maximum cable current carrying capacity, specifically, Specifically, Set i=1 and the number of iterations, the hole positions of the power pipes and the cable laying information generate the hole positions to obtain the parent generation feature sequence; Determine whether i is less than the number of iterations; If yes, performing cloning transformation and mutation transformation on the parental characteristic sequence to generate a child characteristic sequence; Obtaining the cable ampacities of all the child-generation characteristic sequences to obtain an optimal child-generation characteristic sequence, and obtaining the cable ampacities of all the parent-generation characteristic sequences to obtain an optimal parent-generation characteristic sequence; Let i=i+1, randomly generate an external population, the external population is different from the optimal parent feature sequence and the optimal parent feature sequence, the optimal child feature sequence, the obtained optimal parent feature sequence, and the external population together constitute a first sequence, let the parent feature sequence be updated to the first sequence, and perform the step of determining whether i is less than the number of iterations; If not, the iteration is stopped, and the cable current carrying capacity of all the parent characteristic sequences is obtained to obtain the cable current carrying capacity.

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