A hybrid temperature difference power generation sheet with high thermoelectric conversion efficiency

Abstract

The present invention belongs to the technical field of temperature difference power generation, and discloses a hybrid temperature difference power generation sheet with high thermoelectric conversion efficiency, comprising: a cold end face, a hot end face and a thermocouple combination unit located between the two, wherein: the cold end face is divided into a cooling area and a non-cooling area, the cooling area is in contact with a cold source, and the non-cooling area is not in contact with the cold source; the hot end face is completely in contact with the heat source; the thermocouple combination unit adopts a short thermocouple arm combination and a long thermocouple arm combination to construct a parallel and series circuit of the thermocouple, and the thermocouple combination unit is equivalent to one or more simple thermocouples connected in parallel; the hybrid temperature difference power generation sheet includes a plurality of thermocouple combination units, and a plurality of columns of thermocouple combination units are longitudinally arranged on both sides of the center line of the hybrid temperature difference power generation sheet, and different columns of thermocouple combination units are connected in series by a steering metal guide plate to form an integral thermocouple conversion circuit. The present invention has the characteristics of large output current and good external characteristics, and the thermoelectric conversion efficiency is significantly improved.

Description

Technical Field

[0001] The invention relates to the technical field of temperature difference power generation, and in particular to a series-connected temperature difference power generation sheet with high thermoelectric conversion efficiency. Background Art

[0002] Thermoelectric generator is a semiconductor component that can directly convert thermal energy into electrical energy. Its basic theory is the thermoelectric effect. Key technologies include: research and development and preparation of thermoelectric materials, and design and manufacture of thermocouple arrays. Existing thermoelectric generators generally adopt a three-layer structure. The upper and lower layers are the cold end face and hot end face covered by insulating sheets. They contact the cold source and the heat source respectively when working. The middle layer is equipped with multiple groups of thermocouples connected in series, which are elements for thermoelectric conversion. The arms of the thermocouple are made of strip-shaped n-type and p-type semiconductor materials, with the same height and upright setting. When working, they play the dual role of conductive circuit and heat conduction path. The two top ends of the thermocouple arms are staggered and connected with metal guide plates to form the cold junction and hot junction of the thermocouple loop. All cold junctions form the cold end face of the thermoelectric generator, and all hot junctions form the hot end face of the thermoelectric generator. Therefore, the circuit of the thermoelectric generator is connected in series, while the heat path is connected in parallel.

[0003] Thermoelectric power generation chip is the core component of thermoelectric conversion device. Thermoelectric conversion efficiency is one of its most important technical indicators, which is defined as: the ratio of output electric energy to heat absorbed by the hot end (heat absorbed by the hot end includes heat required for thermoelectric conversion and its own heat conduction). At present, the thermoelectric conversion efficiency of thermoelectric power generation chip is only about 4.5%, which is the biggest obstacle in practical application. In order to solve this problem, the scientific and technological community has been developing high-performance thermoelectric materials for the production of thermocouple arms, but there has been no significant progress in research and development results so far. The reason is that it is extremely difficult to require a thermoelectric material to meet the three conditions of high Seebeck coefficient, low resistance and low thermal conductivity at the same time. In addition, in the prior art, the structural defects of the thermoelectric power generation sheet also make it difficult to improve its thermoelectric conversion efficiency. The reasons are: (1) The thermocouples of the thermoelectric power generation sheet are all connected in series. The advantage is that the circuit is relatively simple and the voltage can be increased by superposition. The disadvantage is that the internal resistance is very large, resulting in reactive power loss; (2) The two ends of all thermocouple arms are in contact with the cold end face and the hot end face respectively, forming a parallel connection of the heat conduction path. Due to the existence of the temperature difference, a large amount of heat conduction is inevitably generated between the cold end and the hot end of the thermocouple arm, resulting in reactive power loss of heat absorption at the hot end. Summary of the invention

[0004] In order to overcome the above shortcomings of the prior art, the present invention provides a hybrid thermoelectric power generation sheet with high thermoelectric conversion efficiency. The thermoelectric power generation sheet of the present invention has the characteristics of large output (working) current, good external characteristics, and significantly improved thermoelectric conversion efficiency based on structural design.

[0005] The present invention is implemented by the following technical solutions:

[0006] The hybrid-parallel thermoelectric power generation sheet (abbreviated as: thermoelectric power generation sheet) with high thermoelectric conversion efficiency of the present invention still maintains the external dimensions, thermoelectric materials and scale of the thermocouple arm array of the existing thermoelectric power generation sheet. The hot end surface (hot surface) of the thermoelectric power generation sheet is still in full contact with the heat source to ensure that the heat is absorbed from the heat source to the maximum extent. The principle of changing the cold end surface (cold surface) is to allow only part of the surface area to contact the cold source, that is, to reduce the amount of heat transferred by reducing the heat conduction area of ​​the cold surface. At the same time, a new type of hybrid-parallel thermocouple combination unit with multiple contacts is provided, which solves the problem caused by the circuit being completely connected in series and the heat path being completely connected in parallel in the prior art, thereby achieving the purpose of improving the thermoelectric conversion efficiency. Specifically:

[0007] (1) According to the principle of heat transfer, the amount of heat transferred along a solid is proportional to the temperature difference between its two ends, the thermal conductivity, and the heat conduction area, and inversely proportional to the heat conduction distance. Therefore, the present invention divides the cold end surface of the thermoelectric generator into a cooling area and a non-cooling area. The cooling area needs to be in contact with the cold source, while the non-cooling area does not need to be in contact with the cold source. The two areas are separated from each other and there is no heat transfer. The smaller the area of ​​the cooling area, the less the total amount of heat absorbed by the hot end surface and transferred to the cold end surface through the thermocouple arm.

[0008] (2) According to the principle of electrical engineering, the resistance of a thermocouple arm is proportional to its resistivity and length, and inversely proportional to its cross-sectional area; the basic principle of a thermocouple circuit indicates that the hot junctions of multiple thermocouple combination units connected in parallel can increase the current value of thermoelectric conversion. Therefore, the present invention designs the thermocouple arm into two sizes, a short arm and a long arm, which have equal cross-sectional areas but different heights. The resistance value of the short arm is smaller than that of the long arm, and the total resistance value of all thermocouple arms is reduced. The thermocouple combination unit adopts the form of short arm combination and long arm combination to construct a thermocouple circuit, wherein each pair of n-type material short arm combination and p-type material short arm combination are connected to form two hot junctions of the thermocouple combination unit, and each pair of n-type material long arm combination is connected to the hot end of the p-type material long arm combination to form another hot junction of the thermocouple combination unit, and the hot junction is only heated by the heat source without cooling by the cold source, so it has the same temperature, and a thermocouple combination unit can have multiple hot junctions and be connected in parallel; and the cold end of the long arm combination is respectively connected to the cold end of the long arm combination of the special-shaped material of the adjacent unit to form two cold junctions of the thermocouple combination unit, and the cold junction needs cooling by the cold source. Under the condition that the scale of the thermocouple arm combination array remains unchanged, the present invention increases the number of hot junctions and reduces the number of cold junctions.

[0009] (3) The present invention proposes the principle of coordinated design of circuits and thermal circuits, and sets the thermocouple arm combinations in the cooling area and the non-cooling area according to their functions. The thermocouple arm combinations set in the non-cooling area are all combinations of short arms; in the cooling area, the thermocouple arm combinations set are combinations of long arms and short arms, wherein the height of the long arms remains unchanged, and their resistance value and thermal conductivity remain unchanged, and they are still connected in parallel as thermal circuits to meet the requirements of forming a working temperature difference. Between the cooling area and the non-cooling area, the short arm combination and the long arm combination of the same type of material in the same thermocouple combination unit are connected in series by a metal guide plate, which is a series link in the thermocouple combination power supply, so that the current and heat flow flow from the hot junction to the cold junction, forming a basic thermocouple loop; and the cold junctions of adjacent thermocouple combination units are connected in series by metal guide plates to form an integrated thermocouple circuit and thermal circuit. It achieves the characteristics of reducing resistance, reducing heat conductivity, appropriately reducing voltage and increasing current, and keeping the total power unchanged. It is a high-efficiency thermoelectric generator for engineering applications.

[0010] Specifically:

[0011] A hybrid temperature difference power generation sheet with high thermoelectric conversion efficiency comprises: a cold end surface, a hot end surface and a thermocouple combination unit located between the cold end surface and the hot end surface, wherein:

[0012] The cold end surface is divided into a cooling area and a non-cooling area, the cooling area is in contact with a cold source, and the non-cooling area is not in contact with the cold source; the hot end surface is completely in contact with the heat source;

[0013] The thermocouple combination unit adopts the form of a short thermocouple arm combination and a long thermocouple arm combination to construct a series and parallel circuit of thermocouples, and the thermocouple combination unit is equivalent to one or more simple thermocouples connected in parallel;

[0014] The hybrid temperature difference power generation sheet includes a plurality of thermocouple combination units. Multiple columns of thermocouple combination units are longitudinally arranged on both sides of the center line of the hybrid temperature difference power generation sheet. The thermocouple combination units in different columns are connected in series by turning metal guide plates to form an integrated thermocouple conversion circuit.

[0015] Preferably, the thermocouple combination unit adopts the form of a short thermocouple arm combination and a long thermocouple arm combination to construct a series and parallel circuit of the thermocouple, specifically including: each pair of n-type material short arm combinations and p-type material short arm combinations are connected to form two hot junctions of the thermocouple combination unit, each pair of n-type material long arm combinations are connected to the hot end of the p-type material long arm combination to form another hot junction of the thermocouple combination unit, and the hot junction is only heated by the heat source without the need for cooling by the cold source; and the cold end of the long arm combination is respectively connected to the cold end of the special-shaped material long arm combination of the adjacent unit to form two cold junctions of the thermocouple combination unit, and the cold junction needs to be cooled by the cold source.

[0016] Preferably, the cold surface of the thermoelectric power generation sheet can be provided with one or more cooling areas and one or more non-cooling areas. Moreover, the smaller the cooling area and the larger the non-cooling area, the smaller the heat loss through the thermoelectric power generation sheet and the higher the thermoelectric conversion efficiency.

[0017] Preferably, the thermoelectric power generation sheet is provided with a packaging insulation frame around it, with a circuit lead-out line connector slot, and an upper straight frame bar and a lower straight frame bar are provided between the cooling area and the non-cooling area, and the upper straight frame bar and the lower straight frame bar are made of high temperature resistant insulation material. The upper straight frame bar has a through slot and a turning slot, and the lower straight frame bar is an independent component, used together with the upper straight frame bar.

[0018] Preferably, the non-cooling area is covered with an insulation board, which is made of high-temperature resistant insulating material. The insulation board has a stepped structure on the top and a flat structure on the bottom, which together with the encapsulated insulation frame and the upper and lower straight frame bars form an installation space for the thermal joint.

[0019] Preferably, the thermocouple arms of the temperature difference power generation sheet are made of different types of semiconductor materials, connected in parallel and in series, and used in combination.

[0020] Preferably, the long thermocouple arm combinations and short thermocouple arm combinations of the multiple thermocouple combination units of the hybrid temperature difference power generation sheet form a thermocouple arm combination array, and the thermocouple arm combination array is based on the center line of the hybrid temperature difference power generation sheet, and different types of thermocouple arm combinations are reversely symmetrical; the thermocouple arm combinations in adjacent rows and adjacent columns are staggered.

[0021] Preferably, the thermocouple arm of the temperature difference power generation sheet has two heights (lengths), long and short. The resistance value of the short thermocouple arm is smaller than that of the long thermocouple arm. Moreover, the shorter the length of the short thermocouple arm is, the more beneficial it is to improve the thermoelectric conversion efficiency.

[0022] Preferably, the short thermocouple arm combination (short arm combination) of the temperature difference power generation sheet is composed of short thermocouple arms of the same type of material stacked up and down, with a metal guide plate in the middle; the long thermocouple arm combination (long arm combination) is composed of long thermocouple arms and short thermocouple arms of the same type of material stacked up and down, with a metal guide plate in the middle.

[0023] Preferably, the thermoelectric generator sheet adopts two different sizes of metal guide plates: long and short. The short metal guide plate is used to connect a pair of n-type material thermocouple arm combination and p-type material thermocouple arm combination, and the long metal guide plate is used to connect thermocouple arm combinations of the same type of material.

[0024] Preferably, all thermocouple arm assemblies of a thermocouple assembly unit of the temperature difference power generation sheet are arranged in the cooling area and the non-cooling area according to their functions. The n-type material thermocouple arm assembly and the p-type material thermocouple arm assembly arranged in the cooling area are both long thermocouple arm assemblies, and the hot end surface of the long thermocouple arm assembly contacts the heat source, and the cold end surface contacts the cold source; the n-type material thermocouple arm assembly and the p-type material thermocouple arm assembly arranged in the non-cooling area are both composed of short thermocouple arms, and the short thermocouple arm assembly is only heated by the heat source and not cooled by the cold source. The short thermocouple arm assembly and the long thermocouple arm assembly of the same type of material are connected in series by a long metal guide plate.

[0025] Preferably, the hot end surface of the hybrid temperature difference power generation sheet is a plane, the hot junctions formed by connecting the metal guide plates are connected in parallel, and the temperature of all hot junctions is the same. The hot end surface is provided with a lower straight frame bar, which together with the packaging insulation frame and the upper straight frame bar forms an installation space for the hot junction.

[0026] Preferably, a pair of short thermocouple arms of n-type material and p-type material of the thermoelectric power generation sheet are connected by a short metal guide plate to form a hot junction of a thermocouple combination unit. A thermocouple combination unit can have one or more pairs of hot junctions, and multiple hot junctions are connected in parallel. The number of hot junctions and the size of the short thermocouple arms determine the output current value of the thermoelectric power generation sheet.

[0027] Preferably, a pair of long thermocouple arm combinations of n-type material and p-type material of the thermocouple power generation sheet, their hot ends are heated by a heat source, and their cold ends are cooled by a cold source. A thermocouple combination unit can have one or more pairs of long thermocouple arm combinations, and the long thermocouple arm combinations of the same material are connected in parallel. The cold ends of a pair of long thermocouple arm combinations of special-shaped materials belonging to adjacent thermocouple combination units are connected by short metal guide plates to form a cold junction of a thermocouple combination unit, and the cold junctions are connected in series. The number of cold junctions connected in series and the size of the long thermocouple arms determine the output voltage value of the thermocouple power generation sheet. Preferably, on both sides of the center line of the thermocouple power generation sheet, an array of thermocouple combination units is arranged longitudinally, and the thermocouple combination units in the same column are connected in series by short turning metal guide plates, and the thermocouple combination units in different columns are connected in series by long turning metal guide plates or short turning metal guide plates.

[0028] Preferably, the thermoelectric power generation sheet adopts two different sizes of long and short steering metal guides. The long steering metal guide connects the long thermocouple arm combinations of special-shaped materials separated in adjacent thermocouple combination unit columns; the short steering metal guide connects the long thermocouple arm combinations of special-shaped materials adjacent in adjacent thermocouple combination unit columns. The connection of the two steering metal guides forms a cold junction, and connects multiple columns of thermocouple combination units into an integral thermoelectric conversion circuit.

[0029] Preferably, the cold surface of the thermoelectric power generation sheet may be covered with an insulating plate, and the hot surface may also be covered with an insulating plate.

[0030] Preferably, the thermoelectric power generation sheet technology can also be used in the design of thermoelectric cooling sheets.

[0031] The present invention has the following advantages over the prior art:

[0032] (1) The applicant found that: from the perspective of structural design, the direction of improving the conversion efficiency of the thermoelectric power generation sheet is to reduce the total resistance of the thermocouple array to reduce the loss of output power, and at the same time reduce the heat conduction through the thermocouple arm to reduce the heat loss. Therefore, the present invention is based on existing thermoelectric materials and changes the circuit and heat path structure design of the thermoelectric power generation sheet, which is of great significance for improving the thermoelectric conversion efficiency of the thermoelectric power generation sheet.

[0033] (2) A cooling area and a non-cooling area are set on the cold surface of the thermoelectric power generation sheet, wherein: the thermocouple arms in the non-cooling area do not need to be cooled, which greatly reduces the heat loss generated by heat conduction.

[0034] (3) A combination of long and short thermocouple arms and long and short metal guide plates is used to construct a multi-junction hybrid thermocouple combination unit in which the circuit and the heat circuit are coordinated. This increases the number of hot junctions and reduces the number of cold junctions, thereby reducing the total resistance and significantly improving the thermoelectric conversion efficiency.

[0035] (4) The output voltage of the thermoelectric generator drops reasonably, but the output current increases accordingly, and the total output power remains unchanged, which has good output power characteristics. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is a structural diagram (stereoscopic diagram, cold surface view) of a temperature difference power generation sheet in one embodiment of the present invention.

[0037] Figure 2 1 is a layout diagram of the thermocouple arm combination array of a temperature difference power generation sheet in one embodiment of the present invention (cold side view).

[0038] Figure 3 It is a structural diagram (stereoscopic diagram) of a thermocouple combination unit of a temperature difference power generation sheet in one embodiment of the present invention.

[0039] Figure 4 It is a cold surface connection diagram (cold surface view) of a temperature difference power generation sheet in one embodiment of the present invention.

[0040] Figure 5 It is a hot surface connection diagram (hot surface view) of a temperature difference power generation sheet in one embodiment of the present invention.

[0041] Figure 6It is a packaging and heat insulation block diagram (cold side view) of a temperature difference power generation chip in one embodiment of the present invention.

[0042] Wherein: A, cooling area of ​​the thermoelectric generator (area A); B, non-cooling area of ​​the thermoelectric generator (area B); L (row number, column number), thermocouple arm combination number; C (row number, column number), thermocouple arm combination unit number; E, thermocouple combination unit; N (row number, column number), cold surface guide plate number; M (row number, column number), hot surface guide plate number; t0, center line of the thermoelectric generator; 1, circuit lead wire connector (positive pole); 2, circuit lead wire connector (negative pole); 3, cold surface insulation Hot plate; 4. Packaging insulation frame; 5. Long thermocouple arm of n-type material (n-type long arm); 6. Short thermocouple arm of n-type material (n-type short arm); 7. Long thermocouple arm of p-type material (p-type long arm); 8. Short thermocouple arm of p-type material (p-type short arm); 9. Long metal guide plate; 10. Short metal guide plate; 11. Long turning metal guide plate; 12. Short turning metal guide plate; 13. Circuit lead-out wire connector groove; 14. Upper straight frame bar; 15. Through groove; 16. Turning groove; 17. Lower straight frame bar. DETAILED DESCRIPTION

[0043] The present invention will be further described below in conjunction with the accompanying drawings and embodiments, but the embodiments of the present invention are not limited thereto.

[0044] Figure 1 The figure shows the cold side view of the thermoelectric generator structure. The upper end surface of the thermoelectric generator is its cold side, which is the working surface that directly contacts the cold source and is cooled. The cold side is symmetrically divided into seven areas (such as Figure 2 ): four cooling areas A and three non-cooling areas B. The total area of ​​the cooling areas A is equal to the total area of ​​the non-cooling areas B, and only the cooling areas A can contact the cold source, that is, only 1 / 2 of the cold surface area can be cooled. The non-cooling areas B are covered with a cold surface insulation board 3. The top of the cold surface insulation board 3 is a stepped structure. The position of the long turning metal guide plate 11 is the low-step surface, and the high-step surface of the cold surface insulation board 3 is flush with the cold surface of the thermoelectric power generation sheet. The cold surface insulation board 3 is made of insulating and insulating materials, such as foam materials, fiber materials, and vacuum materials. It can isolate heat flow and electric current, and can prevent hot contacts from contacting the cold source, causing heat transfer and current short circuits. The packaging insulation frame 4 is also made of insulating and insulating materials (such as Figure 6As shown), it is enclosed around the thermoelectric power generation sheet. The upper straight frame bar 14 and the lower straight frame bar 17 are used to separate area A and area B, and cooperate with the cold surface insulation board 3 to isolate area B. The positive pole 1 and the negative pole 2 of the circuit lead-out connector are connected to the external circuit, and output direct current when working. When the thermoelectric power generation sheet is working, an insulating plate can be set on the cold surface. The insulating plate is made of a ceramic plate or other high-temperature resistant insulating material, so that the cold junction can be fully cooled, and the metal guide plate is prevented from directly contacting the cold source to cause a current short circuit.

[0045] A combination of n-type long arms 5 and p-type long arms 7 are arranged in region A. Each of them is made of a long arm and a short arm made of the same type of semiconductor material, welded to the upper and lower surfaces of a long metal guide plate 9, and the short arm hot end surfaces are connected by a short metal guide plate 10 to form a hot junction of the thermocouple combination unit (such as Figure 3 As shown). In region B, there are a combination of n-type short arms 6 and a combination of p-type short arms 8, each of which is made of two short arms made of the same type of semiconductor material welded to the upper and lower surfaces of the long metal guide plate 9, and the hot end surfaces of the two short arms of different types of semiconductor materials in adjacent rows are respectively connected by short metal guide plates 10 to form the other two hot junctions of the thermocouple combination unit (as shown in FIG. Figure 3 As shown); between area A and area B, a long metal guide plate 9 runs through area A and area B, connecting the hot end surfaces of the same type of material arms located in the same row (as shown Figure 3 The function of the long turning metal guide plate 11 and the short turning metal guide plate 12 is to connect the thermocouple combination units of different columns in series (such as Figure 4 As shown), forming an overall thermocouple conversion circuit.

[0046] Figure 1 The lower end surface of the thermoelectric generator is the hot surface of the thermoelectric generator. When working, the entire surface area of ​​the hot surface is heated by the heat source and absorbs the heat of the heat source. The hot surface can also be covered with an insulating plate to ensure sufficient heat transfer between the hot surface and the heat source, while avoiding direct contact between the metal guide plate and the heat source to cause a short circuit.

[0047] Figure 2The figure shows an example of the arrangement structure of the thermocouple arm combination array of the thermoelectric power generation sheet (cold side view). The thermocouple arm array in the figure is 12 rows × 12 columns, consisting of 72 thermocouple arm combinations of n-type materials and 72 thermocouple arm combinations of p-type materials. Among them, each rectangle represents a thermocouple arm combination with a rectangular cross-section, and the same color indicates that it is made of the same type of semiconductor material. The number of the thermocouple arm combination is represented by the symbol L (row number, column number), for example, L (1, 1) represents the thermocouple arm combination located in the first row and the first column. In the array, a pair of long thermocouple arm combinations of special-shaped materials and a pair of short thermocouple arm combinations of special-shaped materials constitute a thermocouple arm combination unit C, wherein the material type of the two thermocouple arm combinations in the same row is the same, while the material type of the two thermocouple arm combinations in adjacent rows is opposite. The labels Ⅰ∽VI represent 6 rows × 6 columns arranged in sequence, totaling 36 thermocouple arm combination units C, and their numbering method is C (row number, column number). For example, C(Ⅳ, VI) represents a thermocouple arm combination unit located in the 4th row and the 6th column, which is composed of L(7, 11), L(7, 12), L(8, 11) and L(8, 12).

[0048] A combination of n-type long arms 5 and a combination of p-type long arms 7 are provided in region A, and they are both formed by stacking a long arm and a short arm of the same material up and down (e.g. Figure 1 and Figure 3 As shown). Area B is provided with short thermocouple arms, including a combination of n-type short arms 6 and a combination of p-type short arms 8, which are both formed by stacking two short arms of the same material up and down (as shown). Figure 1 and Figure 3 Thermocouple arm assembly connection method is as follows Figure 3 , Figure 4 and Figure 5 shown.

[0049] Figure 3 The figure shows the structure and connection method of a multi-junction hybrid thermocouple combination unit E of a temperature difference power generation sheet, which is composed of a thermocouple arm combination unit C (in Figure 2 The number is C (Ⅳ, Ⅵ)) and a metal guide plate. Among them: the number 5 is the n-type long arm, 6 is the n-type short arm, 7 is the p-type long arm, and 8 is the p-type short arm. Figure 1 and Figure 2 As shown in FIG. 1 , in region A, the long arm combination is formed by welding the n-type long arm 5 and the n-type short arm 6 to the upper and lower surfaces of the long metal guide plate 9, and L(8,12) is welded by welding the p-type long arm 7 and the p-type short arm 8 to the upper and lower surfaces of the long metal guide plate 9. In region B, the short arm combination is formed by welding the two n-type short arms 6 to the upper and lower surfaces of the long metal guide plate 9, and L(8,11) is welded by welding the two p-type short arms 8 to the upper and lower surfaces of the long metal guide plate 9.

[0050] Thermocouple arm assembly connection methods include:

[0051] (1) Region A includes two adjacent rows of long arm assemblies L(7, 12) and L(8, 12), whose n-type short arms 6 (not shown) and p-type short arms 8 are connected by a short metal guide plate 10 numbered M(4, 12) to form a hot junction; and two cold junctions are formed by connecting the long arms to the corresponding long arms of special-shaped materials of the adjacent thermocouple arm assembly unit C, such as the cold end face of the n-type long arm 5 of L(7, 12), which is connected to the p-type long arm assembly L(6, 12) of the adjacent thermocouple arm assembly unit C through the short metal guide plate N(3, 12) (e.g. Figure 2 Similarly, the cold end face of the p-type long arm 7 numbered L(8,12) is connected to the cold end face of the n-type long arm combination L(9,12) through the short metal guide plate N(4,12) (as shown in FIG. Figure 2 The two cold junctions are connected in series.

[0052] (2) Area B includes two adjacent rows of short arm combinations L(7, 11) and L(8, 11), whose upper and lower end faces are both hot end faces, respectively connected by short metal guide plates 10 numbered M(4, 11), forming two upper and lower thermal junctions. These two thermal junctions are connected in parallel.

[0053] (3) Between region A and region B, the long thermocouple arm combination and the short thermocouple arm combination of the same type of material are connected in series laterally by a long metal guide plate 9. For example, the n-type long arm combination numbered L(7, 12) and the n-type short arm combination numbered L(7, 11) are connected in series by a long metal guide plate 9; the p-type long arm combination numbered L(8, 12) and the p-type short arm combination numbered L(8, 11) are connected in series by a long metal guide plate 9. At the same time, due to the connection effect of the long metal guide plate 9, the three thermal junctions in region A and region B are connected in parallel.

[0054] Figure 3 It represents a thermocouple combination unit E, in which three hot junctions are connected in parallel and two cold junctions are connected in series, which is equivalent to the parallel connection of three simple thermocouples and is a more compact micro temperature difference power supply.

[0055] Figure 4 The figure is a cold surface connection diagram of the thermoelectric power generation sheet, which shows how all the thermocouple combination units are connected to form a thermoelectric conversion circuit. Among them: the labels Ⅰ to VI represent the six thermocouple arm combination units C arranged in sequence (such as Figure 2 As shown in Figure 1-1). The symbol E represents a thermocouple assembly unit, and the thermocouple arm assembly unit belonging to it is shown in Figure 1-1. Figure 2The label in is C (Ⅳ, Ⅵ), and its thermocouple arm connection method is as follows Figure 3 As shown. Each thermocouple combination unit E contains 6 short arms and 2 long arms. Figure 2 As shown: the n-type long arm combination numbered L(7, 12) is connected to the p-type long arm combination L(6, 12) through the short metal guide plate N(3, 12), and the p-type long arm combination numbered L(8, 12) is connected to the n-type long arm combination L(9, 12) through the short metal guide plate N(4, 12). Similarly, the special-shaped long arms in the adjacent thermocouple arm combination units C are connected through the short metal guide plate 10 to form a series connection of the thermocouple combination units E.

[0056] The thermoelectric power generation sheet has a total of 6 columns of thermocouple combination units E, and the thermocouple circuit turns 5 times from the positive electrode 1 to the negative electrode 2. Therefore, each column of thermocouple combination units E needs to be connected in series through a turning metal guide plate to form an integral thermoelectric conversion circuit. Figure 1 and Figure 2 As shown: the P-type material long thermocouple arm combination L (12, 12) located in the VI column area A is connected in series with the n-type material long thermocouple arm combination L (12, 9) located in the V column area A through the long turning metal guide plate 11, forming a cold junction. The long turning metal guide plate 11 is above the short arm combination and crosses the non-cooling area B. There is a cold surface insulation board 3 between them and they are not in contact; the P-type material long thermocouple arm combination L (12, 8) in the IV column is also connected in series with the n-type material long thermocouple arm combination L (12, 5) located in the III column area A through the long turning metal guide plate 11, forming another cold junction. Similarly, the long arm combination of column II and the long arm combination of special-shaped materials of column I located in area A are also connected in series through the long turning metal guide plate 11 to form a cold junction; while the long arm combinations of column V and column IV located in area A are adjacent to each other, and they are connected in series by the short turning metal guide plate 12 to form a cold junction; similarly, the long arm combinations of column III and column II located in area A are adjacent to each other, and they are also connected in series by the short turning metal guide plate 12. Thus, the positive pole 1 of the circuit lead-out terminal is connected to the negative pole 2 of the circuit lead-out terminal through all the thermocouple arm combinations to form a complete thermocouple circuit.

[0057] Figure 5 This is the hot surface connection diagram of the thermoelectric generator. The hot surface is the end surface that is heated by the heat source when the thermoelectric generator is working. Figure 5 yes Figure 4 The back view of Figure 4 The same thermocouple arm assembly unit C. Figure 5 The thermocouple combination unit E shown is Figure 4 Consistent, its thermocouple arm combination unit is Figure 2 The label in is C (Ⅳ, Ⅵ), and its thermocouple arm connection method is as follows Figure 3 The hot surface connection view of the thermocouple assembly unit E shows that the short metal guide plate M (4, 11) is connected to the lower short arms of L (8, 11) and L (7, 11), and M (4, 12) is connected to the lower short arms of L (8, 12) and L (7, 12). Figure 3 Similarly, the 36 thermocouple combination units E of the thermoelectric power generation sheet example have the same hot surface connection method to ensure that the hot junctions of each thermocouple arm combination have the same temperature. The hot surface position of the lower straight frame bar 17 cooperates with the upper straight frame bar 14 to separate area A and area B. The upper straight frame bar 14 is provided with a through groove 15 in the middle (as shown in FIG. Figure 6 As shown), the long metal guide plate 9 can pass through the through groove 15 and be pressed.

[0058] Figure 6 The heat-insulating frame 4 (cold side view) of the thermoelectric power generation chip is shown. The heat-insulating frame 4 is made of high-temperature resistant insulation material. Four cooling areas A and three non-cooling areas B are arranged in the frame. The area A and the area B are separated by six upper straight frame bars 14 and six lower straight frame bars 17 (as shown in FIG. Figure 1 As shown). Each upper straight frame bar 14 has 11 through slots 15 at the bottom, through which the long metal guide plate 9 can pass. The lower straight frame bar 17 is an independent component, which cooperates with the upper straight frame bar 14 to press the long metal guide plate 9. The turning groove 16 is flush with the stepped surface of the cold face insulation board 3, so that the long turning metal guide plate 11 is flush with the upper plane of the cold face insulation board 3 (as shown). Figure 1 Area B is covered with a cold-surface heat-insulating board 3 to form an isolated thermal space (as shown). Figure 1 As shown in the figure, the hot junction is evenly heated therein, and there is no temperature gradient in steady-state operation. The outer frame of the packaging insulation frame 4 fixes and protects the thermoelectric power generation sheet. The circuit lead-out connector slot 13 serves as an outlet, and is matched with the circuit lead-out connector positive electrode 1 and negative electrode 2 to connect to the external circuit.

[0059] Compared with the existing 12×12 specification thermoelectric power generation sheet, the cooling area of ​​the present invention example is reduced by 1 / 2, and the heat loss is correspondingly reduced by 1 / 2, which nearly doubles the efficiency of thermoelectric conversion. The thermoelectric power generation sheet has 36 thermocouple combination units E connected in series, and each thermocouple combination unit E is equivalent to three simple thermocouples connected in parallel. When the thermoelectric material and cross-sectional area remain unchanged, and meet the following conditions: the height of the short thermocouple arm is ≤1 / 4 of the height of the long thermocouple arm, the output voltage of the power generation sheet is reduced by 1 / 2, but the output current is doubled, so that the total output power value remains unchanged.

[0060] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. A series-connected thermoelectric power generation sheet with high thermoelectric conversion efficiency, characterized in that: The hybrid temperature difference power generation sheet comprises: a cold end surface, a hot end surface and a thermocouple combination unit located between the cold end surface and the hot end surface, wherein: The cold end surface is divided into a cooling area and a non-cooling area, the cooling area is in contact with a cold source, and the non-cooling area is not in contact with the cold source; the hot end surface is completely in contact with the heat source; The thermocouple combination unit adopts the form of a short thermocouple arm combination and a long thermocouple arm combination to construct a parallel and series circuit of thermocouples, and the thermocouple combination unit is equivalent to one or more simple thermocouples connected in parallel; The hybrid temperature difference power generation sheet comprises a plurality of thermocouple combination units, and a plurality of rows of thermocouple combination units are longitudinally arranged on both sides of the center line of the hybrid temperature difference power generation sheet, and different rows of thermocouple combination units are connected in series by turning metal guide sheets to form an integral thermocouple conversion circuit; The short thermocouple arm combination is composed of short thermocouple arms of the same type of material stacked up and down, with a metal guide plate in the middle; the long thermocouple arm combination is composed of a long thermocouple arm and a short thermocouple arm of the same type of material stacked up and down, with a metal guide plate in the middle; All the thermocouple arm assemblies of the thermocouple assembly unit are arranged in the cooling area and the non-cooling area according to their functions; the thermocouple arm assemblies arranged in the cooling area are all long thermocouple arm assemblies, the hot end surface of the long thermocouple arm assemblies contacts the heat source, and the cold end surface contacts the cold source; the thermocouple arm assemblies arranged in the non-cooling area are all short thermocouple arm assemblies, the short thermocouple arm assemblies are only heated by the heat source but not cooled by the cold source; the short thermocouple arm assemblies and the long thermocouple arm assemblies of the same type of material are connected in series by a long metal guide plate.

2. The series-connected thermoelectric generator according to claim 1, characterized in that: The thermocouple combination unit constructs a series and parallel circuit of the thermocouple in the form of a short thermocouple arm combination and a long thermocouple arm combination, specifically including: each pair of short thermocouple arm combinations of n-type materials are connected to the short thermocouple arm combination of p-type materials to form two hot junctions of the thermocouple combination unit; each pair of long thermocouple arm combinations of n-type materials are connected to the hot end of the long thermocouple arm combination of p-type materials to form another hot junction of the thermocouple combination unit, and the hot junction is only heated by the heat source without cooling by the cold source, and thus has the same temperature; and the cold end of the long thermocouple arm combination is respectively connected to the cold end of the long thermocouple arm combination of special-shaped materials of the adjacent unit to form two cold junctions of the thermocouple combination unit, and the cold junction needs to be cooled by the cold source.

3. The series-connected thermoelectric generator according to claim 2, characterized in that: There are one or more pairs of thermal junctions in a thermocouple combination unit, and the thermal junctions are connected in parallel; the number of thermal junctions and the size of the short thermocouple arm determine the output current value of the temperature difference generator.

4. The series-connected thermoelectric generator according to claim 1, characterized in that: The temperature difference power generation sheet adopts two different sizes of long and short steering metal guide plates; the long steering metal guide plate connects the long thermocouple arm combination of special-shaped materials separated in the position in the adjacent thermocouple combination unit column; The short turning metal guide plate connects the long thermocouple arm combinations of adjacent special-shaped materials in adjacent thermocouple combination unit columns; the connection of the two turning metal guide plates forms a cold junction, and connects multiple columns of thermocouple combination units into an integral thermoelectric conversion circuit.

5. The series-connected thermoelectric generator according to claim 1, characterized in that: The cold end surface of the hybrid thermoelectric power generation sheet is provided with one or more cooling areas and one or more non-cooling areas; and the smaller the cooling area and the larger the non-cooling area, the smaller the heat loss through the hybrid thermoelectric power generation sheet and the higher the thermoelectric conversion efficiency.

6. The series-connected thermoelectric generator according to claim 1, characterized in that: The non-cooling area is covered with an insulation board made of high-temperature resistant insulation material; the insulation board has a stepped structure on the top and a flat structure on the bottom, which together with the encapsulated insulation frame and the upper and lower straight frame bars form an installation space for the thermal contact.

7. The series-connected thermoelectric generator according to claim 1, characterized in that: The hot end surface of the hybrid temperature difference power generation sheet is a plane, and the thermal junctions formed by connecting the metal guide plates are all connected in parallel, and the temperature of all the thermal junctions is the same; the hot end surface is provided with a lower straight frame bar, which together with the packaging insulation frame and the upper straight frame bar forms an installation space for the thermal junction.

8. The series-connected thermoelectric generator according to claim 1, characterized in that: The hybrid temperature difference power generation sheet is provided with a packaging insulation frame on the periphery, with a circuit lead-out wire joint slot, and an upper straight frame bar and a lower straight frame bar are provided between the cooling area and the non-cooling area, and the upper straight frame bar and the lower straight frame bar are made of high temperature resistant insulation material; The upper straight frame bar is provided with a through groove and a turning groove, and the lower straight frame bar is an independent component and is used together with the upper straight frame bar.

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