Busbar load flow and temperature rise value calculation method

Abstract

The application provides a bus current carrying capacity and temperature rise value calculation method, including the following steps: based on the basic information of the bus, the heat power and the heat dissipation power of the bus are calculated; based on the heat power and the heat dissipation power, the current carrying capacity calculation formula and the temperature rise value calculation formula of the bus are determined; the actual current maximum value and the actual temperature rise maximum value of the bus are obtained; based on the actual temperature rise maximum value and the current carrying capacity calculation formula, the current carrying capacity of the bus is calculated; based on the actual current maximum value and the temperature rise value calculation formula, the temperature rise value of the bus is calculated. The application provides a set of theoretical calculation formula, which can quickly calculate the current carrying capacity and the temperature rise value of different bus specifications, quickly understand the current carrying capacity and the temperature rise of the bus, so that relevant personnel can design a more reasonable bus cross-sectional area, reduce the production cost and reduce the safety hidden danger.

Description

Technical Field

[0001] This application relates to the technical field of busbars, and more particularly to a method for calculating the current carrying capacity and temperature rise of a busbar. Background Technology

[0002] The busbars inside the battery pack are mainly copper or aluminum busbars. They are long conductors with a rectangular or chamfered (rounded) rectangular cross-section (nowadays, rounded copper busbars are generally used to avoid point discharge). In the circuit, they are used to transmit current and connect electrical equipment (the busbars inside the battery pack mainly connect cells to cells and cells to electrical components (including relays, fuses, high-voltage connectors, etc.)).

[0003] Currently, the design of the high-voltage copper busbar inside the battery pack is mainly designed by R&D engineers based on the total power of the electrical components in the vehicle. However, many young R&D engineers have little project experience and cannot quickly confirm the busbar design. Even experienced senior engineers mostly calculate the cross-sectional area, current carrying capacity and temperature rise of the busbar according to industry experience (copper 5, aluminum 3), which may result in the design of the copper busbar cross-sectional area being too large or too small.

[0004] If the cross-sectional area of ​​the busbar is designed with too large a margin, it will result in excessive copper busbar material usage and increased manufacturing costs; if the cross-sectional area of ​​the busbar is designed with too small a margin, it will result in insufficient current carrying capacity of the busbar, which will further lead to excessive temperature rise, affecting the service life of other electrical components. In some cases, the excessive temperature of the copper busbar may even be transferred to the battery cell, causing the battery cell to have the potential for thermal runaway, which is extremely dangerous. Summary of the Invention

[0005] To quickly understand the current-carrying capacity and temperature rise of a busbar, thereby facilitating the design of a more reasonable busbar cross-sectional area, reducing manufacturing costs and safety hazards, this application proposes a method for calculating the current-carrying capacity and temperature rise of a busbar.

[0006] Firstly, this application proposes a method for calculating the busbar load capacity and temperature rise value, employing the following technical solution:

[0007] A method for calculating the busbar load capacity and temperature rise includes the following steps:

[0008] Based on the basic information of the bus, calculate the heat generation power and heat dissipation power of the bus;

[0009] Based on the heat generation power and the heat dissipation power, the formulas for calculating the current carrying capacity and temperature rise of the busbar are determined.

[0010] Obtain the actual maximum current and actual maximum temperature rise of the bus;

[0011] Based on the actual maximum temperature rise and the current carrying capacity calculation formula, the current carrying capacity of the busbar is calculated.

[0012] The temperature rise of the busbar is calculated based on the actual maximum current and the temperature rise calculation formula.

[0013] Preferably, the basic information includes resistivity, resistivity temperature coefficient, final thermal equilibrium temperature, overall heat dissipation coefficient, ambient temperature, and the length, thickness, and width of the busbar.

[0014] Preferably, the formula for calculating the heating power of the busbar is as follows:

[0015] ;

[0016] In the formula, This refers to the heating power of the bus. This represents the theoretical current carrying capacity of the bus. The resistivity of the busbar at 20°C. Temperature coefficient of resistance The final temperature for thermal equilibrium, Bus length For busbar thickness, This refers to the bus width.

[0017] Preferably, the formula for calculating the heat dissipation power of the bus is as follows:

[0018] ;

[0019] In the formula, This refers to the heat dissipation power of the bus. The overall heat dissipation coefficient of the busbar. This refers to the heat dissipation area of ​​the busbar. This represents the theoretical temperature rise of the busbar.

[0020] Preferably, the current carrying capacity and temperature rise of the busbar are calculated based on the heating power and the heat dissipation power, including:

[0021] In response to the bus temperature stabilizing after power-on, the bus's... ;

[0022] based on Calculate the current carrying capacity and the temperature rise value.

[0023] Preferably, the formulas for calculating the current carrying capacity and temperature rise of the busbar are as follows:

[0024] Formula for calculating current carrying capacity:

[0025] ;

[0026] Formula for calculating temperature rise:

[0027] .

[0028] Preferably, the current carrying capacity of the busbar is calculated based on the actual maximum temperature rise and the current carrying capacity calculation formula, including:

[0029] Substitute the actual maximum temperature rise into the theoretical temperature rise value in the current carrying capacity calculation formula. The current carrying capacity of the busbar is calculated. .

[0030] Preferably, the temperature rise of the busbar is calculated based on the actual maximum current and the temperature rise calculation formula, including:

[0031] Substitute the actual maximum current into the theoretical current carrying capacity in the temperature rise calculation formula. The temperature rise of the busbar was calculated. .

[0032] Secondly, this application proposes a busbar flow rate and temperature rise calculation device, which adopts the following technical solution:

[0033] A device for calculating the current carrying capacity and temperature rise of a busbar includes:

[0034] The power calculation module is used to calculate the heat generation power and heat dissipation power of the bus based on the basic information of the bus;

[0035] The formula acquisition module is used to determine the current carrying capacity calculation formula and the temperature rise value calculation formula of the busbar based on the heat generation power and the heat dissipation power.

[0036] The acquisition module is used to acquire the actual maximum current and the actual maximum temperature rise of the busbar;

[0037] The current carrying capacity calculation module is used to calculate the current carrying capacity of the busbar based on the actual maximum temperature rise and the current carrying capacity calculation formula.

[0038] The temperature rise calculation module is used to calculate the temperature rise value of the busbar based on the actual maximum current and the temperature rise value calculation formula.

[0039] Thirdly, this application proposes an electronic device that adopts the following technical solution:

[0040] An electronic device, comprising:

[0041] A processor, and a memory communicatively connected to the processor;

[0042] The memory stores computer-executed instructions;

[0043] The processor executes computer execution instructions stored in the memory to implement the method described above.

[0044] This application provides a method for calculating the current carrying capacity and temperature rise of a bus. It calculates the heating and cooling power of the bus based on basic information. Responding to the equality of heating and cooling power, it determines the formulas for calculating the current carrying capacity and temperature rise of the bus. Furthermore, it determines the current carrying capacity and temperature rise based on the actual maximum current and actual current temperature rise of the bus, forming a set of theoretical calculation formulas. This method can quickly calculate the current carrying capacity and temperature rise of different bus specifications (different thicknesses and widths), providing a rapid understanding of the bus's current carrying capacity and temperature rise. This facilitates the design of more reasonable bus cross-sectional areas, reduces manufacturing costs, and minimizes safety hazards.

[0045] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0046] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein:

[0047] Figure 1 This is a flowchart illustrating a method for calculating busbar load capacity and temperature rise in an embodiment of this application.

[0048] Figure 2 This is a schematic diagram of the busbar structure in a method for calculating busbar current carrying capacity and temperature rise value according to an embodiment of this application.

[0049] Figure 3 This is a schematic diagram of a busbar flow rate and temperature rise calculation device according to an embodiment of this application.

[0050] Explanation of reference numerals in the attached figures:

[0051] 1. Power calculation module; 2. Formula determination module; 3. Acquisition module; 4. Current carrying calculation module; 5. Temperature rise calculation module. Detailed Implementation

[0052] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0053] The following describes a method for calculating the busbar load capacity and temperature rise value according to an embodiment of this application, with reference to the accompanying drawings.

[0054] Reference Figure 1 This application discloses a method for calculating the busbar capacity and temperature rise, including the following steps:

[0055] S101. Based on the basic information of the bus, calculate the heating power and heat dissipation power of the bus;

[0056] S102. Based on the heating power and heat dissipation power, determine the formula for calculating the current carrying capacity and temperature rise of the busbar;

[0057] S103. Obtain the actual maximum current and actual maximum temperature rise of the busbar;

[0058] S104. Based on the actual maximum temperature rise and the current carrying capacity calculation formula, the current carrying capacity of the busbar is calculated.

[0059] S105. Based on the actual maximum current and the temperature rise calculation formula, the temperature rise of the busbar is calculated.

[0060] Busbars include copper busbars, aluminum busbars, etc. This embodiment uses copper busbars as an example to illustrate the method, and does not impose any limitations on them. Other metal busbars are also applicable to this method.

[0061] Step S101: The basic information of the bus includes resistivity, resistivity temperature coefficient, final thermal equilibrium temperature, overall heat dissipation coefficient, ambient temperature, bus length, thickness, and width. Taking a copper bus as an example, the basic information obtained in this embodiment is shown in Table 1:

[0062] Table 1. Explanation of Basic Information about Copper Busbars

[0063]

[0064] Based on the basic information, calculate the heating power and heat dissipation power of the copper busbar.

[0065] Specifically, the calculation process for the heating power of the copper busbar is as follows:

[0066] According to Joule's law and the formula for resistance:

[0067] ;

[0068] ;

[0069] The formula for heating power can be obtained as follows:

[0070] ;

[0071] because resistivity at ℃ = ,get:

[0072] ;

[0073] In the formula, The heating power of the copper busbar, This represents the theoretical current carrying capacity of the copper busbar. The resistivity of the copper busbar at 20℃ Temperature coefficient of resistance The final temperature for thermal equilibrium, The length of the copper busbar. For the thickness of the copper busbar, This refers to the width of the copper busbar.

[0074] Specifically, refer to Figure 2 The diagram shows the structure of the copper busbar, including its length, width, and height.

[0075] Specifically, the calculation process for the heat dissipation power of the copper busbar is as follows:

[0076] Under normal circumstances, system heat dissipation involves heat conduction. thermal convection There are three forms of thermal radiation, but in engineering, Newton's law of cooling is often used for analysis. Newton's law of cooling states that when a conductor is naturally cooled, and its temperature is higher than the ambient temperature, the rate of heat dissipation is directly proportional to the temperature difference. That is, it determines that:

[0077] ;

[0078] In the formula, This refers to the heat dissipation power of the copper busbar. The overall heat dissipation coefficient of the copper busbar. This refers to the heat dissipation area of ​​the copper busbar. This represents the theoretical temperature rise of the copper busbar.

[0079] Step S102: After determining the heating power and heat dissipation power of the copper busbar, determine the current carrying capacity calculation formula and temperature rise calculation formula of the copper busbar based on the heating power and heat dissipation power of the copper busbar.

[0080] Specifically, the temperature of the copper busbar has stabilized after being energized, therefore the heat generated by the copper busbar during the heating process is... =0. Here C It is specific heat capacity. m It's the quality of the copper busbar. θ This is the current temperature of the copper busbar. This refers to the temperature before the copper busbar. Once the copper busbar temperature stabilizes... Therefore Therefore, the heating power equals the heat dissipation power, that is... .

[0081] Depend on It can be known that ;

[0082] After further derivation and unit conversion, the formula for calculating the current carrying capacity of copper busbars can be obtained as follows:

[0083] ;

[0084] The formula for calculating the temperature rise of copper busbars is:

[0085] .

[0086] Step S103: Obtain the actual maximum current of the copper busbar, which can be obtained from the total power of the electrical components in the entire system; after determining the total power of the entire system, calculate the continuous current of the loop flowing through the copper busbar, i.e., the actual maximum current, based on the total power.

[0087] To obtain the maximum actual temperature rise of the copper busbar, you can refer to the temperature tolerance values ​​of other structural components connected to the copper busbar or the temperature tolerance values ​​of surrounding structural components of the same type, and select the minimum value among them as the maximum actual temperature rise of the copper busbar.

[0088] Step S104: After determining the actual maximum temperature rise, substitute the actual maximum temperature rise into the theoretical temperature rise value in the current carrying capacity calculation formula to calculate the current carrying capacity of the copper busbar.

[0089] Step S105: After determining the maximum actual current, substitute the maximum actual current into the theoretical current carrying capacity of the temperature rise calculation formula to calculate the temperature rise of the copper busbar.

[0090] Table 2 shows copper bus current carrying capacity data calculated based on the actual maximum temperature rise:

[0091] Table 2 shows the copper busbar current carrying capacity data calculated based on the actual maximum temperature rise.

[0092]

[0093] Table 3 shows the copper busbar temperature rise data calculated based on the actual maximum current:

[0094] Table 3. Copper busbar temperature rise data calculated based on the actual maximum current.

[0095]

[0096] Based on the current carrying capacity and temperature rise data of the copper busbar obtained at the maximum actual current and maximum actual temperature rise, the design rationality of the copper busbar can be quickly evaluated.

[0097] The beneficial effects of this application include:

[0098] 1. Shorten project development cycle: The cross-sectional area (width) of the busbar can be quickly determined through calculation formulas. Thickness), reducing busbar design time;

[0099] 2. Reduce busbar costs. By using calculation formulas, the busbar's current carrying capacity can be determined, allowing for the design of a reasonable busbar cross-sectional area. In terms of busbar materials, excessive design margins will not lead to increased busbar costs.

[0100] 3. Improve product safety. The temperature rise of the busbar can be determined by calculation formula. When the temperature rise is too high, heat will be transferred to the battery cell, causing the battery cell temperature to be too high, which may lead to thermal runaway.

[0101] 4. Improve product reliability and durability. If the bus design specifications are too low, the temperature rise value will be too high when the bus is working for a long time. This will affect the surrounding structural components (output stage base, CCS) and electrical components (low voltage wiring harness, relay, fuse, pre-charge resistor), causing them to be in a high temperature environment for a long time, which will reduce the service life of the structural and electrical components.

[0102] 5. Establish a bus design experience library. In the early stage, bus design is carried out through theoretical calculation formulas. In the middle stage of the project, bus thermal simulation and bus temperature rise experiments will be carried out. The difference between the two will be compared. Different bus design specifications will be selected according to different scenarios, forming a complete theoretical + experimental system.

[0103] It is worth mentioning that the application scenarios of this application are not limited to the busbars in power battery packs, but can also be used in many other scenarios such as distribution cabinets and high-voltage boxes (where current is carried by the busbars), and this application does not impose any restrictions on this.

[0104] Reference Figure 3 This application also discloses a device for calculating busbar current carrying capacity and temperature rise, comprising:

[0105] Power calculation module 1 is used to calculate the heat generation power and heat dissipation power of the bus based on the basic information of the bus;

[0106] Formula determination module 2 is used to determine the bus current carrying capacity calculation formula and temperature rise value calculation formula based on the heating power and heat dissipation power;

[0107] Module 3 is used to obtain the actual maximum current and the actual maximum temperature rise of the busbar;

[0108] The current carrying capacity calculation module 4 is used to calculate the current carrying capacity of the busbar based on the actual maximum temperature rise and the current carrying capacity calculation formula.

[0109] Temperature rise calculation module 5 is used to calculate the temperature rise value of the busbar based on the actual maximum current and the temperature rise value calculation formula.

[0110] It should be noted that the foregoing explanation of an embodiment of a method for calculating the flow rate and temperature rise of a busbar also applies to a device for calculating the flow rate and temperature rise of a busbar in this embodiment, and will not be repeated here.

[0111] To implement the above embodiments, this application also proposes an electronic device, including: a processor and a memory communicatively connected to the processor; the memory stores computer-executable instructions; the processor executes the computer-executable instructions stored in the memory to implement the method provided in the foregoing embodiments.

[0112] It should be noted that personal information collected from users should be used for legitimate and reasonable purposes and should not be shared or sold outside of these legitimate uses. Furthermore, such collection / sharing should only be conducted after receiving the user's informed consent, including but not limited to notifying the user to read the user agreement / user notice and sign an agreement / authorization that includes authorization of relevant user information before the user uses the function. In addition, any necessary steps must be taken to protect and safeguard access to such personal information data and ensure that others with access to personal information data comply with their privacy policies and procedures.

[0113] This application is intended to provide an implementation scheme for users to selectively prevent the use or access to their personal information data. Specifically, this disclosure is intended to provide hardware and / or software to prevent or block access to such personal information data. Once personal information data is no longer needed, risks can be minimized by restricting data collection and deleting data. Furthermore, where applicable, such personal information is de-identified to protect user privacy.

[0114] In the foregoing descriptions of the embodiments, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0115] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0116] Any process or method description in the flowchart or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or more executable instructions for implementing custom logic functions or processes, and the scope of the preferred embodiments of this application includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order depending on the functions involved, as should be understood by those skilled in the art to which embodiments of this application pertain.

[0117] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequential list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-including system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device.

[0118] It should be understood that various parts of this application can be implemented using hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented using software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0119] Those skilled in the art will understand that all or part of the steps of the methods in the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, the program includes one or a combination of the steps of the method embodiments.

[0120] Furthermore, the functional units in the various embodiments of this application can be integrated into a processing module, or each unit can exist physically separately, or two or more units can be integrated into a module. The integrated module can be implemented in hardware or as a software functional module. If the integrated module is implemented as a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium.

[0121] The storage medium mentioned above can be a read-only memory, a disk, or an optical disk, etc. Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of this application.

Claims

1. A method for calculating the busbar flow rate and temperature rise, characterized in that, The busbar is a copper busbar, and the method includes the following steps: Based on the basic information of the bus, calculate the heat generation power and heat dissipation power of the bus; Based on the heat generation power and the heat dissipation power, the formulas for calculating the current carrying capacity and temperature rise of the busbar are determined. Obtain the actual maximum current and actual maximum temperature rise of the bus; Based on the actual maximum temperature rise and the current carrying capacity calculation formula, the current carrying capacity of the busbar is calculated. The temperature rise of the busbar is calculated based on the actual maximum current and the temperature rise calculation formula. The current carrying capacity and temperature rise of the busbar are calculated based on the heat generation power and the heat dissipation power, including: In response to the bus temperature stabilizing after power-on, it is determined that the heating power P1 of the bus is equal to the heat dissipation power P2. Based on the fact that the heating power P1 equals the heat dissipation power P2, calculate the current carrying capacity and the temperature rise value; The formulas for calculating the current carrying capacity and temperature rise of the busbar are as follows: Formula for calculating current carrying capacity: ； Formula for calculating temperature rise: in, The overall heat dissipation coefficient of the bus is expressed in W / (m²). 2 K), This represents the theoretical temperature rise of the busbar, in °C. Busbar thickness, in mm. This refers to the bus width, in mm. The resistivity of the busbar at 20°C. This is the temperature coefficient of resistance, expressed in ppm / ℃. The final thermal equilibrium temperature, expressed in °C. The initial ambient temperature is expressed in °C. .

2. The method according to claim 1, characterized in that, The basic information includes resistivity, resistivity temperature coefficient, final thermal equilibrium temperature, overall heat dissipation coefficient, ambient temperature, and the length, thickness, and width of the bus.

3. The method according to claim 2, characterized in that, The formula for calculating the heating power of the busbar is as follows: ； In the formula, This refers to the heating power of the bus. This represents the theoretical current carrying capacity of the bus. This is the bus length.

4. The method according to claim 3, characterized in that, The formula for calculating the heat dissipation power of the bus is as follows: ； In the formula, This refers to the heat dissipation power of the bus. This refers to the heat dissipation area of ​​the busbar.

5. The method according to claim 1, characterized in that, Based on the actual maximum temperature rise and the current carrying capacity calculation formula, the current carrying capacity of the busbar is calculated, including: Substitute the actual maximum temperature rise into the theoretical temperature rise value in the current carrying capacity calculation formula. The current carrying capacity of the busbar is calculated. .

6. The method according to claim 1, characterized in that, Based on the actual maximum current and the temperature rise calculation formula, the temperature rise of the busbar is calculated, including: Substitute the actual maximum current into the theoretical current carrying capacity in the temperature rise calculation formula. The temperature rise of the busbar was calculated. .

7. A device for calculating the current carrying capacity and temperature rise of a busbar, characterized in that, The busbar is a copper busbar, and the device includes: The power calculation module is used to calculate the heat generation power and heat dissipation power of the bus based on the basic information of the bus; The formula determination module is used to determine the current carrying capacity calculation formula and the temperature rise value calculation formula of the busbar based on the heating power and the heat dissipation power. The acquisition module is used to acquire the actual maximum current and the actual maximum temperature rise of the busbar; The current carrying capacity calculation module is used to calculate the current carrying capacity of the busbar based on the actual maximum temperature rise and the current carrying capacity calculation formula. The temperature rise calculation module is used to calculate the temperature rise value of the busbar based on the actual maximum current and the temperature rise value calculation formula. The current carrying capacity and temperature rise of the busbar are calculated based on the heat generation power and the heat dissipation power, including: In response to the bus temperature stabilizing after power-on, it is determined that the heating power P1 of the bus is equal to the heat dissipation power P2. Based on the fact that the heating power P1 equals the heat dissipation power P2, calculate the current carrying capacity and the temperature rise value; The formulas for calculating the current carrying capacity and temperature rise of the busbar are as follows: Formula for calculating current carrying capacity: ； Formula for calculating temperature rise: in, The overall heat dissipation coefficient of the bus is expressed in W / (m²). 2 K), This represents the theoretical temperature rise of the busbar, in °C. Busbar thickness, in mm. This refers to the bus width, in mm. The resistivity of the busbar at 20°C. This is the temperature coefficient of resistance, expressed in ppm / ℃. The final thermal equilibrium temperature, expressed in °C. The initial ambient temperature is expressed in °C. .

8. An electronic device, characterized in that, include: A processor, and a memory communicatively connected to the processor; The memory stores computer-executed instructions; The processor executes computer execution instructions stored in the memory to implement the method as described in any one of claims 1-6.

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