Method for enhancing modularized thermoelectric power generation array with non-uniform temperature distribution

Abstract

The invention belongs to the technical field of thermoelectric power generation, and discloses a non-uniform temperature distribution modular thermoelectric power generation array enhancement method, which comprises the following steps: pre-configuring a TEG array arranged in a square shape; if any side length of the array is an even number, performing vertical and horizontal segmentation by taking the geometric center of the array as a base point, and uniformly dividing the array to form four areas; the first array module and the second array module are classified into a first switching group, and the third array module and the fourth array module are classified into a second switching group. The non-uniform temperature distribution modular thermoelectric power generation array enhancement method disclosed by the invention is suitable for most thermoelectric power generation scenes, is simple in logic, can be directly expanded to a larger-scale TEG array, is different from dynamic reconstruction which needs to be controlled through a large number of switches depending on a complex algorithm, and reduces the switching and construction operation cost.

Description

Technical Field

[0001] The present invention belongs to the technical field of thermoelectric power generation, and in particular relates to a method for enhancing a modular thermoelectric power generation array with non-uniform temperature distribution. Background Art

[0002] Currently, the efficiency of thermoelectric power generation is very low. One of the reasons for this shortcoming is the impedance mismatch between the TEG and the load. MPPT methods, using DC-DC converters, can eliminate this incompatibility while delivering a stable voltage value to the load, maximizing power extraction. However, these MPPT methods all adjust the output voltage to track the GMPP, without fundamentally changing the operating state of the TEG array. In other words, the voltage imbalance between columns in the TEG array remains unchanged, and the multi-peak characteristics of the PU line remain unchanged, potentially leading to serious safety hazards and unnecessary power loss. Therefore, there is an urgent need to reconfigure the TEG array to reorganize and distribute the non-uniform temperature differences, enabling the TEG array to operate under relatively uniform temperature conditions. This would fundamentally address these issues, fully tap the system's power generation potential, and improve power generation efficiency. Depending on the implementation method, reconfiguration can be divided into static and dynamic reconfiguration. Dynamic reconfiguration requires a large number of sensors, relays, and switches, which not only increases cost but also complicates algorithmic research. Therefore, research on static reconfiguration within a fixed array structure is crucial. Currently, there are many dynamic reconfiguration methods for thermoelectric arrays, but static reconfiguration is relatively scarce. However, in photovoltaic systems, many methods for static reconfiguration of photovoltaic arrays have been developed. The uneven temperature distribution of thermoelectric arrays is comparable to partial shading in photovoltaic systems. Summary of the Invention

[0003] In view of this, the present invention provides a method for enhancing a modular thermoelectric power generation array with non-uniform temperature distribution to solve the above problems.

[0004] In order to solve the above technical problems, the present invention provides

[0005] A method for enhancing a modular thermoelectric power generation array with non-uniform temperature distribution, comprising:

[0006] Pre-configured TEG array in a square arrangement;

[0007] If the length of any side of the array is an even number, vertical and horizontal divisions are performed with the geometric center of the array as the base point, and the array is evenly divided to form a first array module, a second array module, a third array module, and a fourth array module;

[0008] After the first array module and the second array module are classified into a first exchange group and the third array module and the fourth array module are classified into a second exchange group, exchange sequences of the first exchange group and the second exchange group are constructed respectively; wherein,

[0009] There are multiple exchange sequences, which are used to exchange TEG modules in different regions within the same exchange group.

[0010] As an alternative, any side length of the array being even includes:

[0011] The number of TEG modules on any side forming the TEG array is even.

[0012] As an alternative, the first array module is adjacent to the second array module and the third array module; the fourth array module is adjacent to the second array module and the third array module; the first array module and the second array module are point - centrosymmetric about the geometric center of the array.

[0013] As an alternative, the TEG modules participating in the same exchange sequence are initially located in different regions.

[0014] As an alternative, in any array module, the end - point TEG modules of any exchange sequence and the同侧端点TEG modules in other exchange sequences are arranged along the main diagonal of the array module.

[0015] As an alternative, the exchange rule of the exchange sequence is:

[0016] After determining the size of the TEG array, obtain the side length m, the number of rows i, and the number of columns j;

[0017] If m is even, then:

[0018] Exchange the TEG modules at positions (i, j) and (i, m / 2 + 1 + j), and exchange the TEG modules at positions (m / 2 + 1 + i, j) and (m / 2 + 1 + i, m / + 1 + j); and after each exchange, i and j are incremented by +1 respectively;

[0019] When i < m / 2 and j < m / 2, the exchange is completed.

[0020] The beneficial effects of the present invention are:

[0021] The method for enhancing a modular thermoelectric generation array with non - uniform temperature distribution disclosed by the present invention is applicable to most thermoelectric generation scenarios, has a simple logic, can be directly extended to larger - scale TEG arrays, is different from dynamic reconfiguration which relies on complex algorithms and is controlled by a large number of switches, and reduces the switch and construction and operation costs. Brief Description of the Drawings

[0022] Figure 1 It is a schematic flowchart of the method for enhancing a modular thermoelectric generation array provided in Embodiment 1 of the present invention;

[0023] Figure 2A schematic diagram of the modular TEG array system structure provided in Example 1 of the present invention;

[0024] Figure 3 A schematic diagram of the initial temperature difference module distribution of a 6×6 array in a scenario provided by Example 1 of the present invention;

[0025] Figure 4 A schematic diagram of temperature difference module exchange in a 6×6 array in a scenario provided by Example 1 of the present invention;

[0026] Figure 5 A schematic diagram of temperature difference module reconstruction of a 6×6 array in a scenario provided by Example 1 of the present invention;

[0027] Figure 6 A schematic diagram of the placement of TEGs in a temperature difference array in a scenario provided by Example 1 of the present invention;

[0028] Figure 7 A schematic diagram of the connection method of each array group provided in Example 2 of the present invention;

[0029] Figure 8 The uneven temperature distribution of the thermoelectric power generation array in Scenario 1 provided in Example 2 of the present invention;

[0030] Figure 9 The uneven temperature distribution of the thermoelectric power generation array in Scenario 2 provided in Example 2 of the present invention;

[0031] Figure 10 The uneven temperature distribution of the thermoelectric power generation array in Scenario 3 provided in Example 2 of the present invention;

[0032] Figure 11 Output characteristic curves of each array PU in scenario 1 provided by embodiment 2 of the present invention;

[0033] Figure 12 This is the local PU output characteristic curve for scenario 1 provided in Example 2 of the present invention;

[0034] Figure 13 Output characteristic curves of each array PU in scenario 2 provided by embodiment 2 of the present invention;

[0035] Figure 14 The local PU output characteristic curve for scenario 2 provided in embodiment 2 of the present invention;

[0036] Figure 15 Output characteristic curves of each array PU in scenario 3 provided in embodiment 2 of the present invention;

[0037] Figure 16 This is the local PU output characteristic curve for scenario 3 provided in embodiment 2 of the present invention. DETAILED DESCRIPTION

[0038] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described in detail below in conjunction with specific implementation methods.

[0039] Example 1

[0040] This embodiment designs a modular diagonal switching strategy (MDS strategy), which exchanges the positions of some TEG modules in the array without changing the electrical connections, making the non-uniform temperature distribution more uniform, thereby improving power output and reducing mismatch loss. This strategy is implemented by exchanging the physical position of a single TEG power generation module located on the main diagonal between array modules. Each TEG can be located by subscripts i and j. The basic idea of ​​this method is that, considering the temperature difference power generation scenario, the cold end temperature remains basically unchanged, the hot end temperature gradually decreases evenly along the airflow direction, and the temperature distribution is mainly symmetrical.

[0041] Based on this strategy, in order to overcome the problem of the lack of static reconstruction in the prior art, this embodiment provides a method for enhancing a modular thermoelectric power generation array with non-uniform temperature distribution, including:

[0042] Pre-configured TEG array in a square arrangement;

[0043] If the length of any side of the array is an even number, vertical and horizontal divisions are performed with the geometric center of the array as the base point, and the array is evenly divided to form a first array module, a second array module, a third array module, and a fourth array module, a total of four array modules;

[0044] After the first array module and the second array module are classified into a first exchange group and the third array module and the fourth array module are classified into a second exchange group, exchange sequences are respectively constructed for the first exchange group and the second exchange group. There are multiple exchange sequences configured, which are used to exchange TEG modules in different areas within the same exchange group.

[0045] For implementation in this embodiment, please refer to Figure 1 and Figure 2 , the length of any side of the array is an even number means that the number of TEG modules on any side of the TEG array is an even number; the first array module is adjacent to the second array module and the third array module; the fourth array module is adjacent to the second array module and the third array module; the first array module and the second array module are point-centered symmetric about the geometric center of the array ( Figure 2 Each module is 1 / 4 the size of the original array. In any array module, the endpoint TEG modules of any switching sequence are arranged along the main diagonal of the array module with the same-side endpoint TEG modules in other switching sequences.

[0046] Please refer to the following for implementation in this embodiment. Figure 1 , the exchange rules of the exchange sequence described in this embodiment are:

[0047] After selecting a TEG matrix array of size m*m, obtain the side length m, the number of rows i, and the number of columns j;

[0048] Determine the starting TEG module of the current array. The starting TEG module has row number i=1 and column number j=1. If m is an even number, then:

[0049] Exchange the TEG modules at positions (i, j) and (i, m / 2+j), and exchange the TEG modules at positions (m / 2+i, j) and (m / 2+i, m / 2+j); and after each exchange, i and j are incremented by +1 respectively.

[0050] When i>m / 2 and j>m / 2, the exchange is completed.

[0051] Specifically, see Figure 3-Figure 6 ,exist Figure 3 In the table, T1-T4 represent the current temperatures of the TEG module. Figure 4 The TEG11 and TEG14, TEG22 and TEG25, TEG33 and TEG36, TEG41 and TEG44, TEG52 and TEG55, TEG63 and TEG66 are swapped. According to the above rules, the array configuration after reconstruction is as follows Figure 5 As shown in the figure, it can be clearly seen that this method distributes the high and low temperature modules more evenly in each column, thereby improving the output power. For a clearer understanding, Figure 6 The specific connection mode between TEGs after the exchange of individual TEG positions under the MDS reconstruction strategy is shown. Although the mobile TEG changes the temperature of the hot end by exchanging the physical position, the connection mode does not change. Therefore, the temperature distribution after equivalent is as follows: Figure 5 shown.

[0052] Thus, based on the traditional array configuration, this embodiment proposes a modular array structure, in which the modular SP&SP array (a modular SP&SP array refers to a single TEG first formed into small modules through SP connection, and then these small modules of the same size are connected through SP to form a large TEG array) demonstrates its superiority in both reliability and output power; only the physical position of the module is changed, and only two modules are exchanged in each row, which reduces power loss and saves costs.

[0053] The MDS strategy proposed in this embodiment is applicable to most thermoelectric power generation scenarios. Its logic is simple and can be directly expanded to larger TEG arrays. Unlike dynamic reconfiguration, which requires complex algorithms and control through a large number of switches, this strategy reduces switching and construction and operating costs. Furthermore, the method described in this embodiment has certain limitations on the size of thermoelectric power generation arrays, namely, it is only applicable to square arrays. Other models can be designed based on the methods of this embodiment as needed.

[0054] Example 2

[0055] This embodiment is based on the method described in the above embodiment 1. Considering the three common temperature distribution conditions in general implementation scenarios, the MDS strategy structure MDS type proposed in the above embodiment 1 is compared with six types of temperature difference power generation arrays, including the traditional array structure SP type (series-parallel connection), TCT type (full cross connection), BL type (bridge connection), modular array structure SP&SP type (series-parallel connection within the module and then series-parallel connection between modules), BL&TCT type (bridge connection within the module and then cross connection between modules), and S type (ideal maximum output power connection method, which can generate the maximum power by connecting all modules in series, but has low reliability). Please refer to the connection method of the above-mentioned array groups for details. Figure 7 shown.

[0056] See also Figures 8-16 ,This embodiment sets three types of uneven temperature distribution of ,thermoelectric power generation arrays under the same environment, and draws the ,local PU and array PU output characteristic curves respectively, ,and obtains data of different performance indicators.

[0057] See also Figure 11-12 In scenario 1, the maximum output powers achieved by the SP, TCT, BL, SP&SP, BL&TCT, and MDS (the structure of this embodiment) were 41.51W, 38.62W, 40.66W, 41.15W, 40.52W, and 47.03W, respectively. Under these experimental conditions, the MDS array had the lowest power loss, at 4.72%, and achieved a 14.29% power increase compared to the TCT array.

[0058] See also Figure 13-14 In scenario 2, the maximum output powers achieved by SP, TCT, BL, SP&SP, BL&TCT, and MDS were 46.46 W, 44.72 W, 46.38 W, 46.62 W, ​​45.72 W, and 48.47 W, respectively. Under these experimental conditions, the MDS array had the lowest power loss of 2.02%, and its power was increased by 3.99% compared to the TCT array.

[0059] See also Figure 15-16In scenario 3, the maximum output powers achieved by the SP, TCT, BL, SP&SP, BL&TCT, and MDS were 56.76W, 55.01W, 56.18W, 56.23W, 55.09W, and 59.25W, respectively. Under these experimental conditions, the MDS array had the lowest power loss, at 0.90%, and achieved a 5.37% power increase compared to the TCT array. P (W) represents the array's output power, and U (V) represents the voltage.

[0060] Table 1 shows the performance data for scenarios 1-3 under the experimental conditions of this example. It summarizes the ideal maximum output power, maximum output power after reconstruction, loss rate, and power improvement percentage of various array structures under corresponding temperature distribution scenarios. The ideal output power value is the value of the S-type structure.

[0061] Table 1 Performance indicator data for scenarios 1-3

[0062]

[0063]

[0064] The power loss of the entire array is expressed as:

[0065] M Loss =P MAX -P max

[0066] Loss rate:

[0067]

[0068] Among them, P MAX Represents the ideal maximum output power, P max Represents the actual maximum output power.

[0069] Power boost percentage:

[0070]

[0071] Among them, P Mre Represents the maximum output power after array reconstruction, P Mbe Represents the maximum output power of the array before reconstruction.

[0072] Through the above solution, this embodiment, based on the MDS strategy, only swaps the positions of some TEG modules in the array without changing the electrical connections, thus making the uneven temperature distribution more uniform, thereby improving power output and reducing mismatch losses. Furthermore, compared with the four traditional array structures, the proposed SP&SP modular array structure improves array reliability while maintaining maximum output power.

[0073] The above are merely preferred embodiments of the present invention. It should be noted that the above preferred embodiments should not be construed as limiting the present invention, and the scope of protection of the present invention should be determined by the scope defined in the claims. Persons skilled in the art will appreciate that improvements and modifications may be made without departing from the spirit and scope of the present invention, and such improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for enhancing a modular thermoelectric power generation array with non-uniform temperature distribution, characterized in that: Comprising: A pre-configured TEG array arranged in a square layout; If any side length of the array is an even number, perform vertical and horizontal division with the geometric center of the array as the base point, and evenly divide the array to form a first array module, a second array module, a third array module, and a fourth array module; After classifying the first array module and the second array module into a first exchange group, and classifying the third array module and the fourth array module into a second exchange group, construct the exchange sequences of the first exchange group and the second exchange group respectively; wherein, There are multiple configured exchange sequences, which are used to exchange TEG modules in different regions within the same exchange group.

2. The method for enhancing a modular thermoelectric power generation array with non-uniform temperature distribution according to claim 1, characterized in that: Any side length of the array being an even number includes: The number of TEG modules on any side constituting the TEG array is an even number.

3. The method for enhancing a modular thermoelectric power generation array with non-uniform temperature distribution according to claim 1, characterized in that: The first array module is adjacent to the second array module and the third array module; the fourth array module is adjacent to the second array module and the third array module; the first array module and the second array module are point-centered symmetric with respect to the geometric center of the array.

4. The method for enhancing a modular thermoelectric power generation array with non-uniform temperature distribution according to claim 1, characterized in that: TEG modules of the same exchange sequence are initially located in different regions.

5. The method for enhancing a modular thermoelectric power generation array with non-uniform temperature distribution according to claim 1, characterized in that: In any array module, the end-point TEG modules of any exchange sequence and the end-point TEG modules on the same side in other exchange sequences are arranged along the main diagonal of the array module.

6. The method for enhancing a modular thermoelectric power generation array with non-uniform temperature distribution according to claim 1, characterized in that: The exchange rule of the exchange sequence is: After determining the size of the TEG array, obtain the side length m, the number of rows i, and the number of columns j; If m is an even number, then: Exchange the TEG modules at positions (i, j) and (i, m / 2 + 1 + j), and exchange the TEG modules at positions (m / 2 + 1 + i, j) and (m / 2 + 1 + i, m / 2 + 1 + j); and after each exchange, i and j are incremented by +1 respectively; When i < m / 2 and j < m / 2, the exchange is completed.

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