JP2015115590A - Thermoelectric conversion module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technique for improving power generation efficiency of a thermoelectric conversion module.SOLUTION: A thermoelectric conversion module 10 includes a plurality of n-type thermoelectric conversion elements 5n and a plurality of thermoelectric conversion elements 5p. Each of thermoelectric conversion elements 5n, 5p has approximately rectangular parallelepiped shapes having the same height and is arrayed like a grid between first and second ceramic substrates 1, 2. Each of the thermoelectric conversion elements 5n, 5p is arrayed in such a way that the area of each upper surface 5u is gradually increased in a first plane direction X. When the thermoelectric conversion module 10 is arranged on a surface of heat source piping 30, the thermoelectric conversion module 10 is arranged in such manner that the upper surfaces 5u are opposed to the surface of the heat source piping 30 and the thermoelectric conversion elements having upper surfaces 5u of larger areas are arranged more downstream of the heat source piping 30.

Description

  The present invention relates to a thermoelectric conversion module.

  The thermoelectric conversion module is a power generation device including a plurality of thermoelectric conversion elements connected in series. In the thermoelectric conversion module, each thermoelectric conversion element receives heat from a heat source and generates power by the Seebeck effect.

  Patent Document 1 discloses a laminated thermoelectric conversion module in which n-type semiconductor ceramic plates and p-type semiconductor ceramic plates, which are thermoelectric conversion elements, are alternately laminated. Patent Document 2 discloses a thermoelectric conversion module configured by only one of an n-type thermoelectric conversion element and a p-type thermoelectric conversion element.

  Japanese Patent Application Laid-Open No. 2003-228867 discusses different configurations between an n-type thermoelectric conversion element and a p-type thermoelectric conversion element in consideration of a difference in electrical characteristics and thermal characteristics between the n-type thermoelectric conversion element and the p-type thermoelectric conversion element. A thermoelectric conversion module is disclosed. Patent Document 4 discloses a technique for converting thermal energy of exhaust gas into electric power by a thermoelectric conversion element.

Japanese Patent Laid-Open No. 1-183862 JP 60-127770 A Japanese Patent Application Laid-Open No. 11-274577 JP 63-262075 A

  By the way, when the heat source brought into contact with the thermoelectric conversion module has a temperature distribution, the power generation amount of the thermoelectric conversion elements constituting the thermoelectric conversion module differs depending on the arrangement position. An equal current flows through each thermoelectric conversion element connected in series regardless of the arrangement position. For this reason, a part of the electrical energy obtained by the thermoelectric conversion element arranged in the portion having a relatively high temperature is consumed in order to pass a current through the thermoelectric conversion element arranged in the portion having a relatively low temperature. As described above, when the heat source has a temperature distribution, a part of the electrical energy generated in the thermoelectric conversion element is wasted in the thermoelectric conversion module, and the power generation efficiency of the entire thermoelectric conversion module is reduced. There is a possibility that.

  However, none of the above Patent Documents 1-4 considers a case where the heat source to which the thermoelectric conversion module is attached has a temperature distribution. Thus, sufficient improvement has not been made so far to improve the power generation efficiency of the thermoelectric conversion module when attached to a heat source having a temperature distribution.

  The present invention has been made to solve the above-described problems, and can be realized as the following forms.

[1] According to one aspect of the present invention, a thermoelectric conversion module is provided. This thermoelectric conversion module includes a plurality of thermoelectric conversion elements that are arranged in a predetermined arrangement direction with heat receiving surfaces for receiving heat facing in the same direction and electrically connected in series. good. The plurality of thermoelectric conversion elements may include at least one of an n-type thermoelectric conversion element and a p-type thermoelectric conversion element. At least one of the n-type thermoelectric conversion element and the p-type thermoelectric conversion element may be arranged such that a heat receiving area, which is an area of the heat receiving surface, gradually increases along the arrangement direction, and extends from the heating element. And when the heat receiving surface is disposed on the surface of the extending member having a temperature distribution in which the temperature decreases as it is separated from the heating element, the heat receiving surface is disposed to face the surface of the extending member, and the heat receiving area is Larger ones may be arranged so as to be located on the downstream side when viewed from the heating element. According to the thermoelectric conversion module of this form, waste of electrical energy in the module caused by the temperature distribution of the extending member that is a heat source is suppressed. Therefore, the power generation efficiency of the thermoelectric conversion module can be increased.

[2] In the thermoelectric conversion module according to the above aspect, at least one of the n-type thermoelectric conversion element and the p-type thermoelectric conversion element is arranged so that the heat receiving area increases in each arrangement position along the arrangement direction. May be. According to the thermoelectric conversion module of this form, waste of electrical energy in the module is further suppressed.

[3] In the thermoelectric conversion module of the above aspect, the plurality of thermoelectric conversion elements extend in parallel with the heat receiving surface as a bottom surface; at least one of the n-type thermoelectric conversion element or the p-type thermoelectric conversion element is The smaller the height relative to the heat receiving surface, the lower the heat receiving area in the arrangement direction. According to the thermoelectric conversion module of this form, waste of electrical energy in the module is suppressed by adjustment by the height of the thermoelectric conversion element.

[4] In the thermoelectric conversion module of the above aspect, the plurality of thermoelectric conversion elements includes a plurality of sets of thermoelectric conversions including a pair of n-type thermoelectric conversion elements and p-type thermoelectric conversion elements arranged adjacent to each other in the arrangement direction. In the plurality of pairs of thermoelectric conversion elements, the heat receiving areas An and Ap of the n-type conversion element and the p-type conversion element may be gradually increased along the arrangement direction. According to the thermoelectric conversion module of this form, waste of electrical energy in the module is suppressed.

[5] In the thermoelectric conversion module of the above aspect, in each of the plurality of thermoelectric conversion element pairs, the heat receiving area An of the n-type thermoelectric conversion element and the heat receiving area Ap of the p-type thermoelectric conversion element are: They may be different from each other. According to the thermoelectric conversion module of this embodiment, the heat receiving areas An and Ap of both can be adjusted according to the difference in characteristics between the n-type thermoelectric conversion element and the p-type thermoelectric conversion element. Therefore, the power generation efficiency of the thermoelectric conversion module can be further increased.

[6] In the thermoelectric conversion module of the above aspect, the rate of change of the heat receiving area An of the n-type thermoelectric conversion elements according to the arrangement position of the thermoelectric conversion element pairs in the arrangement direction, and the arrangement of the thermoelectric conversion element pairs The rate of change of the heat receiving area Ap of the p-type thermoelectric conversion element according to the arrangement position in the direction may be different from each other. According to the thermoelectric conversion module of this embodiment, the rate of change of the heat receiving areas An and Ap can be adjusted according to the difference in characteristics between the n-type thermoelectric conversion element and the p-type thermoelectric conversion element. Therefore, the power generation efficiency of the thermoelectric conversion module can be further increased.

[7] In the thermoelectric conversion module of the above aspect, in the thermoelectric conversion element pair, the plurality of thermoelectric conversion elements are a plurality of first thermoelectric conversion elements; next to a row of the plurality of first thermoelectric conversion elements. A plurality of second thermoelectric conversion elements arranged to correspond to each of the plurality of first thermoelectric conversion elements are arranged in the arrangement direction; and the second thermoelectric conversion elements are adjacent to each other. When the matching first thermoelectric conversion element is an n-type thermoelectric conversion element, the first thermoelectric conversion element is a p-type thermoelectric conversion element. When the adjacent first thermoelectric conversion element is a p-type thermoelectric conversion element, the n-type thermoelectric conversion element is used. In the set of adjacent first and second thermoelectric conversion elements, the heat receiving area An of the n-type thermoelectric conversion element and the heat receiving area Ap of the p-type thermoelectric conversion element are: An / Ap = {(ρn / κn) · ( κp / ρp)} 1/2 of the relationship It may not meet. Here, κn and κp are the thermal conductivity in the n-type thermoelectric conversion element or the p-type thermoelectric conversion element, respectively, and ρn and ρp are the volumes in the n-type thermoelectric conversion element or the p-type thermoelectric conversion element, respectively. Resistivity. According to the thermoelectric conversion module of this embodiment, the heat receiving areas An and Ap of the n-type thermoelectric conversion elements and the p-type thermoelectric conversion elements arranged in the same row in a predetermined arrangement direction are appropriately determined according to the characteristics of both Adjusted.

  The present invention can also be realized in various forms other than the thermoelectric conversion module. For example, a thermoelectric conversion module and a power generation apparatus or power generation system including a stretching member such as a pipe that is a heat source having a temperature distribution, a stretching member provided with the thermoelectric conversion module, a moving body such as a vehicle including the stretching member, and mechanical equipment Or the like.

The schematic perspective view of a thermoelectric conversion module. Schematic which shows the electrical connection structure of each thermoelectric conversion element in a thermoelectric conversion module. The schematic diagram which shows the use condition of a thermoelectric conversion module. The schematic perspective view of the thermoelectric conversion module of a comparative example. Schematic which shows the electrical connection structure of each thermoelectric conversion element in the thermoelectric conversion module of a comparative example. The schematic diagram which shows the use condition of the thermoelectric conversion module of a comparative example. Schematic which shows the structure of the thermoelectric conversion module of 2nd Embodiment. Schematic which shows the structure of the thermoelectric conversion module of 3rd Embodiment. Schematic which shows the structure of the thermoelectric conversion module of 4th Embodiment. Schematic which shows the structure of the thermoelectric conversion module of 5th Embodiment. Schematic which shows the structure of the thermoelectric conversion module of 6th Embodiment. Schematic which shows the structure of the thermoelectric conversion module of 7th Embodiment. Schematic which shows the structure of the thermoelectric conversion module of 8th Embodiment. Schematic which shows the structure of the thermoelectric conversion module of 9th Embodiment.

A. First embodiment:
The configuration of the thermoelectric conversion module 10 as the first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a schematic perspective view of the thermoelectric conversion module 10. FIG. 2 is a schematic diagram showing an electrical connection configuration of the thermoelectric conversion elements 5n and 5p in the thermoelectric conversion module 10. FIG. 2 illustrates the upper surface 5u of each thermoelectric conversion element 5n, 5p when the thermoelectric conversion elements 5n, 5p are viewed along the height direction (the direction of arrow Z). FIG. 3 is a schematic diagram showing a usage state of the thermoelectric conversion module 10. In FIG. 3, the thermoelectric conversion module 10, the heat source pipe 30, and the refrigerant pipe 40 are illustrated by a schematic cross-sectional view when viewed from the side surface direction of the thermoelectric conversion module 10.

  Here, in FIGS. 1 to 3, arrows X, Y, and Z indicating three directions orthogonal to each other are illustrated corresponding to the thermoelectric conversion module 10 as follows. Arrows X and Y indicate directions parallel to two orthogonal sides on the top and bottom surfaces of the thermoelectric conversion module 10, respectively, and an arrow Z indicates a direction parallel to the side surfaces of the thermoelectric conversion module 10 and perpendicular to the top and bottom surfaces. ing. Hereinafter, the direction indicated by the arrow X in the thermoelectric conversion module 10 is referred to as “first plane direction X”, the direction indicated by the arrow Y is referred to as “second plane direction Y”, and the direction indicated by the arrow Z is “high”. This is referred to as “direction Z”. These arrows X, Y, and Z are similarly shown in the explanatory diagrams of the second to sixth embodiments described later.

  The thermoelectric conversion module 10 is attached to a heat source pipe 30 that is a fluid pipe through which a high-temperature fluid such as a high-temperature gas flows, and converts heat received from the heat source pipe 30 into electric power using the Seebeck effect (FIG. 3). Here, the “high temperature” may be a temperature higher than that of the refrigerant flowing through the refrigerant pipe 40, and may be, for example, a temperature of room temperature or higher. The heat source pipe 30 may be an exhaust gas pipe of a moving body such as an automobile, or may be a pipe laid in a factory or a house. The heat source pipe 30 corresponds to an extending member having a temperature distribution that extends from the heating element and decreases in temperature as the heating element is separated from the heating element.

  The thermoelectric conversion module 10 includes first and second ceramic substrates 1 and 2, a plurality of n-type thermoelectric conversion elements 5n, a plurality of p-type thermoelectric conversion elements 5p, and a plurality of contact members 7 (FIG. 1). The first and second ceramic substrates 1 and 2 are ceramic plate-like members, each having the same rectangular shape. The first and second ceramic substrates 1 and 2 are arranged so as to sandwich the thermoelectric conversion elements 5n and 5p in the height direction Z through a contact member 7 which is a conductive member. Part. In the present embodiment, the direction parallel to the long sides of the first and second ceramic substrates 1 and 2 is the first plane direction X, and the direction parallel to the short sides is the second plane direction Y. .

  The n-type thermoelectric conversion element 5n and the p-type thermoelectric conversion element 5p are composed of an n-type thermoelectric material and a p-type thermoelectric material, respectively. Each thermoelectric conversion element 5n, 5p has a substantially rectangular parallelepiped shape having substantially the same height. However, the area of the upper surface 5u of each thermoelectric conversion element 5n, 5p varies depending on the arrangement position, as will be described later. In the present embodiment, the n-type thermoelectric conversion element 5n and the p-type thermoelectric conversion element 5p have a value of the ratio κ / ρ (hereinafter referred to as “κρ ratio”) between the thermal conductivity κ and the volume resistivity ρ. It is desirable to be composed of equal thermoelectric materials. As a result, waste of electrical energy caused by the difference in material characteristics between the n-type thermoelectric conversion element 5n and the p-type thermoelectric conversion element 5p is suppressed.

  In the thermoelectric conversion module 10 of the present embodiment, the n-type thermoelectric conversion element 5n and the p-type thermoelectric conversion element 5p are arranged in a lattice (matrix) so that they are adjacent to each other in the first and second plane directions X and Y. It is arranged. All the thermoelectric conversion elements 5n and 5p are electrically connected in series in the order in which the n-type thermoelectric conversion elements 5n and the p-type thermoelectric conversion elements 5p are alternately repeated (FIG. 2). In the thermoelectric conversion module 10 of the present embodiment, the thermoelectric conversion elements 5n and 5p are connected so that the conductive path reciprocates in the first plane direction X. The thermoelectric conversion elements 5n and 5p at the beginning and end of the conductive path are connected to the external load 20 through the power supply line 8, respectively.

  Here, a combination of an n-type thermoelectric conversion element 5n and a p-type thermoelectric conversion element 5p of the same size, which are arranged adjacent to each other and connected via a contact member 7 arranged on the bottom surface 5b side, is expressed as “ This is referred to as “thermoelectric conversion element pair 5c”. Each thermoelectric conversion element pair 5c is connected in series via a contact member 7 disposed on the upper surface 5u side.

  By the way, in the thermoelectric conversion module 10 of this embodiment, the area of the upper surface 5u that is a heat receiving surface that receives heat in each of the thermoelectric conversion elements 5n and 5p (hereinafter also referred to as “heat receiving area”) is each thermoelectric conversion element pair 5c. Every time, it gradually increases along the first plane direction X. In the present embodiment, the heat receiving area in the thermoelectric conversion elements 5n and 5p is increased every two rows arranged in the first plane direction X. This is a configuration corresponding to the temperature distribution of the heat source pipe 30 that is a heat source, as will be described below.

  As described above, the thermoelectric conversion module 10 is attached to the heat source pipe 30 during use (FIG. 3). More specifically, the thermoelectric conversion module 10 is disposed so that the first ceramic substrate 1 is in contact with the heat source pipe 30 and the first plane direction X coincides with the flow direction of the high-temperature fluid in the heat source pipe 30. The

  Further, when the thermoelectric conversion module 10 is used, a refrigerant pipe 40 through which a refrigerant such as cooling water flows is disposed on the ceramic substrate 2 of the thermoelectric conversion module 10. The refrigerant pipe 40 is arranged so that the flow direction of the refrigerant is opposite to the flow direction of the high-temperature fluid in the heat source pipe 30. A material having high thermal conductivity such as silicon grease may be disposed between each of the heat source pipe 30 and the refrigerant pipe 40 and the first and second ceramic substrates 1 and 2.

  In this attached state, each thermoelectric conversion element 5n, 5p of the thermoelectric conversion module 10 receives heat from the heat source pipe 30 on the upper surface 5u and is deprived of heat by the refrigerant in the refrigerant pipe 40 on the bottom surface 5b. Thereby, each thermoelectric conversion element 5n, 5p generates an electromotive force according to a temperature difference between the upper surface 5u side and the bottom surface 5b side (Seebeck effect).

  Here, the heat source pipe 30 has a temperature distribution in which the temperature decreases from upstream to downstream, and the temperature gradient in the refrigerant pipe 40 is so small that it can be ignored with respect to the temperature gradient in the heat source pipe 30. Therefore, in the thermoelectric conversion module 10 attached to the heat source pipe 30, the temperature difference between the upper surface 5 u side and the bottom surface side 5 b side increases as the upstream thermoelectric conversion element pair 5 c increases, and the downstream thermoelectric conversion element pair The temperature difference between the upper surface 5u side and the bottom surface side 5b side becomes smaller by about 5c.

  As described above, the thermoelectric conversion module 10 of the present embodiment is attached to the heat source pipe 30 so that the heat receiving area of the thermoelectric conversion element pair 5c is smaller toward the upstream side and the heat receiving area of the thermoelectric conversion element pair 5c is larger toward the downstream side. It is done. As a result, as described below, waste of electrical energy in the thermoelectric conversion module 10 due to the temperature distribution of the heat source pipe 30 is suppressed more than in the power generation module 100a of the comparative example, and the thermoelectric conversion module 10 as a whole. The power generation efficiency when looking at is improved.

  A configuration of a thermoelectric conversion module 10a as a comparative example will be described with reference to FIGS. 4 to 6 correspond to FIGS. 1 to 3, respectively. FIG. 4 is a schematic perspective view of a thermoelectric conversion module 10a of a comparative example. FIG. 5 is a schematic diagram showing an electrical connection configuration of the thermoelectric conversion elements 5n and 5p in the thermoelectric conversion module 10a of the comparative example. FIG. 6 is a schematic diagram illustrating a usage state of the thermoelectric conversion module 10a of the comparative example. The thermoelectric conversion module 10a of the comparative example is the same as the thermoelectric conversion module 10 of the present embodiment (FIG. 1) except that the thermoelectric conversion elements 5n and 5p are all formed in the same size and the area of the upper surface 5u is the same. To FIG. 3).

  In the thermoelectric conversion module 10a of the comparative example, the heat receiving areas of the thermoelectric conversion elements 5n and 5p are uniform regardless of the temperature distribution in the heat source pipe 30. Therefore, the electrical energy output from each thermoelectric conversion element pair 5 c increases toward the upstream side according to the temperature distribution in the heat source pipe 30. Accordingly, a part of the electrical energy generated in the upstream thermoelectric conversion element pair 5c is consumed to cause a current to flow through the downstream thermoelectric conversion element pair 5c, and the power generation efficiency of the thermoelectric conversion module 10a as a whole decreases. It has been.

  On the other hand, in the thermoelectric conversion module 10 of the present embodiment, the thermoelectric conversion element pair 5c having a small heat receiving area is arranged on the downstream side corresponding to the temperature distribution of the heat source pipe 30, and the thermoelectric conversion element pair having a large heat receiving area. 5c is arrange | positioned downstream. Therefore, the electrical energy generated in each thermoelectric conversion element pair 5c when attached to the heat source pipe 30 is suppressed from being consumed in the other thermoelectric element pairs 5c, and when viewed from the entire thermoelectric conversion module 10. Is higher than that of the thermoelectric conversion module 10c of the comparative example.

  As described above, according to the thermoelectric conversion module 10 of the present embodiment, waste of electrical energy in the module due to the temperature distribution of the heat source pipe 30 is suppressed, and heat energy is converted into electrical energy with high efficiency. can do.

B. Second embodiment:
FIG. 7 is a schematic diagram showing a configuration of a thermoelectric conversion module 10A as the second embodiment of the present invention. FIG. 7 illustrates the electrical connection configuration of the thermoelectric conversion elements 5n and 5p in the thermoelectric conversion module 10A of the second embodiment by a schematic diagram similar to FIG. 2 used for the description of the first embodiment. is there. The thermoelectric conversion module 10A of the second embodiment has substantially the same configuration as the thermoelectric conversion module 10 of the first embodiment, except for the points described below.

  In the thermoelectric conversion module 10A of the second embodiment, the heat receiving areas of the n-type thermoelectric conversion element 5n and the p-type thermoelectric conversion element 5p are different in each thermoelectric conversion element pair 5c. Specifically, the respective heat receiving areas of the n-type thermoelectric conversion element 5n and the p-type thermoelectric conversion element 5p in each thermoelectric conversion element pair 5c are the thermoelectric material of the n-type thermoelectric conversion element 5n and the p-type thermoelectric conversion element 5p. It is set according to each κρ ratio. In addition, in the thermoelectric conversion module 10A of the second embodiment, each of the n-type thermoelectric conversion element 5n and the p-type thermoelectric conversion element 5p when viewed with respect to each of the n-type thermoelectric conversion element 5n and the p-type thermoelectric conversion element 5p. The heat receiving area (the area of the upper surface 5 u) increases in order every two rows along the first plane direction X.

  In the case of the thermoelectric conversion module 10A of the second embodiment, the power generation caused by the difference in the characteristics of the constituent materials between the n-type thermoelectric conversion element 5n and the p-type thermoelectric conversion element 5p constituting each thermoelectric conversion element pair 5c. It is suppressed that the difference in efficiency arises. In addition, when attached to the heat source pipe 30, waste of electrical energy in the module due to the temperature distribution of the heat source pipe 30 is suppressed.

C. Third embodiment:
FIG. 8 is a schematic diagram showing a configuration of a thermoelectric conversion module 10B as a third embodiment of the present invention. FIG. 8 illustrates an electrical connection configuration of the thermoelectric conversion elements 5n and 5p in the thermoelectric conversion module 10B of the third embodiment by a schematic diagram similar to FIG. 7 used for describing the second embodiment. is there. The thermoelectric conversion module 10B of the third embodiment has substantially the same configuration as the thermoelectric conversion module 10A of the second embodiment, except for the points described below.

  In the thermoelectric conversion module 10B of the third embodiment, when viewed with respect to each of the n-type thermoelectric conversion element 5n and the p-type thermoelectric conversion element 5p, the respective heat receiving areas of the n-type thermoelectric conversion element 5n and the p-type thermoelectric conversion element 5p. The (area of the upper surface 5u) increases in order for each column along the first plane direction X. Therefore, according to the thermoelectric conversion module 10B of the third embodiment, the heat receiving area of each of the thermoelectric conversion elements 5n and 5p can be finely set according to the temperature distribution in the fluid flow direction of the heat source pipe 30.

Here, in the thermoelectric conversion module 10B of the third embodiment, the heat receiving areas An and Ap of the n-type thermoelectric conversion element 5n and the p-type thermoelectric conversion element 5p adjacent in the second plane direction Y are as follows. It is desirable that the relationship of Formula (1) is satisfied. As a result, the waste of electrical energy between the n-type thermoelectric conversion element 5n and the p-type thermoelectric conversion element 5p arranged at the same temperature in the heat source pipe 30 is suppressed.
An / Ap = {(ρn / κn) · (κp / ρp)} ^1/2 (1)
κn: thermal conductivity of n-type thermoelectric conversion element κp: thermal conductivity of p-type thermoelectric conversion element ρn: volume resistivity of n-type thermoelectric conversion element ρp: volume resistivity of p-type thermoelectric conversion element

D. Fourth embodiment:
FIG. 9 is a schematic diagram showing a configuration of a thermoelectric conversion module 10C as the fourth embodiment of the present invention. FIG. 9 illustrates an electrical connection configuration of the thermoelectric conversion elements 5n and 5p in the thermoelectric conversion module 10C of the fourth embodiment by a schematic diagram similar to FIG. 8 used for describing the third embodiment. is there. The thermoelectric conversion module 10C of the fourth embodiment has substantially the same configuration as the thermoelectric conversion module 10B of the third embodiment, except for the points described below.

Here, in the first plane direction X, the heat received by the n-type thermoelectric conversion elements 5n and p-type thermoelectric conversion elements 5p arranged in the Nth column (N is an arbitrary natural number) and the N + 1th column from the upstream end. The areas are An _N , Ap _N , An _{N + 1} , and Ap _{N + 1} , respectively. At this time, in the thermoelectric conversion module 10C of the fourth embodiment, the heat receiving areas An _N , Ap _N , An _{N + 1} , and Ap _{N + 1} have the relationship of An _{N + 1} / An _N ≠ Ap _{N + 1} / Ap _N. Meet. Thus, in the thermoelectric conversion module 10C of the fourth embodiment, the rate of change of the heat receiving area of the n-type thermoelectric conversion element 5n according to the arrangement position in the first plane direction X and the heat receiving area of the p-type thermoelectric conversion element 5p. Are different from each other. Thus, according to the thermoelectric conversion module 10C of the fourth embodiment, the heat receiving area of each thermoelectric conversion element 5n, 5p according to the arrangement position can be set finely according to the temperature distribution of the heat source pipe 30.

  In general, the Seebeck coefficient, volume resistivity, and thermal conductivity that affect the power generation characteristics of thermoelectric materials have temperature dependence, and the dependence varies depending on the constituent materials. Therefore, in the thermoelectric conversion module 10C of the fourth embodiment, the rate of change in the heat receiving area of each thermoelectric conversion element 5n, 5p in the first plane direction X depends on the actual temperature distribution at the mounting position in the heat source pipe 30. It is desirable to set. Further, the heat receiving areas An and Ap of the n-type thermoelectric conversion element 5n and the p-type thermoelectric conversion element 5p adjacent to each other in the second plane direction Y are the thermal conductivity κ at the temperature at the mounting position of the heat source pipe 30 and In the volume resistivity ρ, it is desirable to satisfy the relationship of the above formula (1).

  As described above, according to the thermoelectric conversion module 10C of the fourth embodiment, the heat receiving area of each thermoelectric conversion element 5n, 5p according to the arrangement position can be finely set according to the temperature distribution of the heat source pipe 30. . Therefore, the power generation efficiency of the thermoelectric conversion module 10C of the fourth embodiment can be further increased.

E. Fifth embodiment:
FIG. 10 is a schematic diagram showing a configuration of a thermoelectric conversion module 10D as the fifth embodiment of the present invention. FIG. 10 illustrates the electrical connection configuration of the thermoelectric conversion elements 5n and 5p in the thermoelectric conversion module 10D of the fifth embodiment by a schematic diagram similar to FIG. 9 used for describing the fourth embodiment. is there. The thermoelectric conversion module 10D of the fifth embodiment has substantially the same configuration as the thermoelectric conversion module 10C of the fourth embodiment except for the points described below.

  In the thermoelectric conversion module 10D of the fifth embodiment, for the n-type thermoelectric conversion element 5n, the aspect ratio of the upper surface 5u is changed in the first plane direction X, but at the arrangement position in the first plane direction X. Regardless, the heat receiving area is the same. On the other hand, for the p-type thermoelectric conversion element 5p, the heat receiving area is increased for each row along the first plane direction X. Even if it is such a structure, when it attaches to the heat source piping 30, the waste of the electrical energy in each p-type thermoelectric conversion element 5p is suppressed. Therefore, a decrease in power generation efficiency of the thermoelectric conversion module 10D due to the temperature distribution of the heat source pipe 30 is suppressed.

F. Sixth embodiment:
FIG. 11 is a schematic diagram showing a configuration of a thermoelectric conversion module 10E as a sixth embodiment of the present invention. In the upper part of FIG. 11, the electrical connection configuration of the thermoelectric conversion elements 5 n and 5 p in the thermoelectric conversion module 10 </ b> E of the sixth embodiment is illustrated by a schematic diagram similar to FIG. 9 used for describing the fourth embodiment. It is shown. However, in the upper part of FIG. 11, the external load 200 is not shown for convenience. Further, in the lower part of FIG. 11, a schematic cross-sectional view of the thermoelectric conversion module 10 </ b> E of the sixth embodiment in the AA cut shown in the upper part of FIG. 11 is illustrated so as to correspond to the upper part of FIG. 11. The thermoelectric conversion module 10E of the sixth embodiment has substantially the same configuration as the thermoelectric conversion module 10C (FIG. 9) of the fourth embodiment except for the points described below.

  In the thermoelectric conversion module 10E of the sixth embodiment, the height h with reference to the upper surface 5u that is the heat receiving surface of each thermoelectric conversion element 5n, 5p is configured to gradually decrease in the first plane direction X. A site is provided. A metal member 9 is replenished between the bottom surface 5b of the thermoelectric conversion elements 5n and 5p having a small height and the contact member 7. By replenishing the metal member 9, the parallel arrangement relationship between the first and second ceramic substrates 1 and 2 is maintained. The metal member 9 is desirably a material that can be connected in ohmic contact with the thermoelectric material that constitutes each of the thermoelectric conversion elements 5n and 5p. In addition, a buffer layer may be provided between each thermoelectric conversion element 5n, 5p and the metal member 9 in order to ensure an ohmic connection therebetween.

  According to the thermoelectric conversion module 10E of the sixth embodiment, the waste of electrical energy in the module due to the temperature distribution of the heat source pipe 30 is added to the heat receiving area of each thermoelectric conversion element 5n, 5p, and the heat receiving surface is changed. It can also be suppressed by the reference height h. Therefore, the power generation efficiency of the thermoelectric conversion module 10E of the sixth embodiment can be further increased.

G. Seventh embodiment:
FIG. 12 is a schematic diagram showing a configuration of a thermoelectric conversion module 10F as a seventh embodiment of the present invention. FIG. 12 illustrates a schematic cross-sectional view of a cut surface parallel to the side surface of the thermoelectric conversion module 10 </ b> F of the seventh embodiment, and a schematic cross-sectional view of the heat source pipe 30 and the refrigerant pipe 40. In FIG. 12, arrows X, Y, and Z indicating three directions orthogonal to each other are illustrated in correspondence with the thermoelectric conversion module 10F of the seventh embodiment as follows.

  An arrow X indicates the stacking direction of the plate-like thermoelectric conversion elements 5Pn and 5Pp of the thermoelectric conversion module 10F of the seventh embodiment. Hereinafter, the direction indicated by the arrow X is also referred to as “stacking direction X”. Arrows Y and Z indicate directions parallel to two orthogonal sides of the surfaces of the plate-like thermoelectric conversion elements 5Pn and 5Pp, respectively. An arrow Z indicates a direction perpendicular to a surface (hereinafter referred to as “upper surface 10 u”) facing the heat source of the thermoelectric conversion module 10 </ b> F of the seventh embodiment. These arrows X, Y, and Z are similarly illustrated in the explanatory diagrams of the eighth embodiment and the ninth embodiment described below.

  The thermoelectric conversion module 10F of the seventh embodiment is a so-called laminated thermoelectric conversion module, and is configured as a laminated body in which n-type plate-like thermoelectric conversion elements 5Pn and p-type plate-like thermoelectric conversion elements 5Pp are alternately laminated. Has been. The n-type plate thermoelectric conversion element 5Pn and the p-type plate thermoelectric conversion element 5Pp are respectively composed of a plate-like n-type thermoelectric material and a p-type thermoelectric material. In each of the plate-like thermoelectric conversion elements 5Pn and 5Pp, the surfaces parallel to the arrows Y and Z have a substantially rectangular shape with the same area. In addition, in the thermoelectric conversion module 10F of 7th Embodiment, the n-type plate-shaped thermoelectric conversion element 5Pn and the p-type plate-shaped thermoelectric conversion element 5Pp which are adjacent to the lamination direction X comprise the pair of thermoelectronic element pair 5c. In each thermoelectronic element pair 5c, the n-type plate thermoelectric conversion element 5Pn and the p-type plate thermoelectric conversion element 5Pp may have different thicknesses t.

  A contact member 7 and an insulating member 6 are interposed between the n-type plate-like thermoelectric conversion element 5Pn and the p-type plate-like thermoelectric conversion element 5Pp. The plate-like thermoelectric conversion elements 5Pn and 5Pp are separated by an insulating member 6 and electrically connected by a contact member 7. The contact members 7 are alternately arranged on the upper surface 10 u side and the opposite lower surface 10 b side in the stacking direction X.

  The thermoelectric conversion module 10 </ b> F of the seventh embodiment is attached to the heat source pipe 30 similarly to the thermoelectric conversion modules 10, 10 </ b> A to 10 </ b> E of each of the above embodiments, and generates power by receiving heat from the heat source pipe 30. The thermoelectric conversion module 10F of the seventh embodiment is attached to the heat source pipe 30 so that the stacking direction X coincides with the fluid flow direction in the heat source pipe 30 and the upper surface 10u is in surface contact. In addition, the refrigerant | coolant piping 40 is arrange | positioned similarly to the thermoelectric conversion modules 10 and 10A-10E of each said embodiment on the lower surface 10b of the thermoelectric conversion module 10F of 7th Embodiment. A material having high thermal conductivity such as silicon grease may be disposed between the thermoelectric conversion module 10F of the seventh embodiment and the heat source pipe 30 and the refrigerant pipe 40.

  Here, in the thermoelectric conversion module 10F of 7th Embodiment, the thickness t of each plate-shaped thermoelectric conversion element 5Pn and 5Pp is comprised so that it may become large gradually along the lamination direction X. As shown in FIG. More specifically, each set of adjacent n-type plate-like thermoelectric conversion elements 5Pn and p-type plate-like thermoelectric conversion elements 5Pp is configured so that the thickness t increases along the stacking direction X. Therefore, in the thermoelectric conversion module 10F of the seventh embodiment, the area of the side surface 5s parallel to the arrows X and Y that function as the heat receiving surfaces of the plate-like thermoelectric conversion elements 5Pn and 5Pp gradually increases along the stacking direction X. Yes.

  With this configuration, in the thermoelectric conversion module 10F of the seventh embodiment, it is suppressed that electrical energy is wasted between the respective plate-like thermoelectric conversion elements 5Pn and 5Pp due to the temperature distribution in the heat source pipe 30. Has been. Therefore, according to the thermoelectric conversion module 10F of the seventh embodiment, it is possible to obtain higher power generation efficiency than a stacked thermoelectric conversion module in which plate-shaped thermoelectric conversion elements having a uniform thickness are stacked.

H. Eighth embodiment:
FIG. 13 is a schematic diagram showing a configuration of a thermoelectric conversion module 10G as an eighth embodiment of the present invention. FIG. 13 illustrates a schematic cross-sectional view of a cut surface parallel to the side surface of the thermoelectric conversion module 10 </ b> G of the eighth embodiment, and a schematic cross-sectional view of the heat source pipe 30 and the refrigerant pipe 40. The thermoelectric conversion module 10G of the eighth embodiment of the thermoelectric conversion module 10G has substantially the same configuration as the thermoelectric conversion module 10F (FIG. 12) of the seventh embodiment, except for the points described below.

  In the thermoelectric conversion module 10G of the eighth embodiment, when viewed with respect to each of the n-type plate thermoelectric conversion element 5Pn and the p-type plate thermoelectric conversion element 5Pp, the height h with respect to the upper surface 10u is in the stacking direction X. A portion configured to gradually become smaller is provided. Among the plate-like thermoelectric conversion elements 5Pn and 5Pp having a small height, the height h of the adjacent n-type plate-like thermoelectric conversion element 5Pn and p-type plate-like thermoelectric conversion element 5Pp is the Seebeck coefficient and the thermal conductivity of the constituent material, respectively. , Depending on the volume resistivity. A metal member 9 is replenished on the bottom surface 10b side of each plate-like thermoelectric conversion element 5Pn, 5Pp having a small height h. Thereby, the bottom surface 10b of each plate-like thermoelectric conversion element 5Pn, 5Pp is configured to be substantially flat.

  In the thermoelectric conversion module 10G of the eighth embodiment, the waste of electrical energy between the plate-like thermoelectric conversion elements 5Pn and 5Pp due to the temperature distribution of the heat source pipe 30 is caused by the occurrence of the waste of electric energy in each plate-like thermoelectric conversion element 5Pn. In addition to the adjustment of the thickness 5Pp, the height h can be suppressed by adjusting the upper surface 5u as a reference. Therefore, the power generation efficiency of the thermoelectric conversion module 10G of the eighth embodiment can be further increased.

I. Ninth embodiment:
FIG. 14 is a schematic diagram showing a configuration of a thermoelectric conversion module 10H as a ninth embodiment of the present invention. FIG. 14 illustrates a schematic cross-sectional view of a cut surface parallel to the side surface of the thermoelectric conversion module 10 </ b> H of the ninth embodiment, and a schematic cross-sectional view of the heat source pipe 30 and the refrigerant pipe 40. The thermoelectric conversion module 10H of the ninth embodiment is a so-called unileg type laminated thermoelectric conversion module, and is configured as a laminated body in which a plurality of n-type plate-like thermoelectric conversion elements 5Pn are laminated. Between each n-type plate-like thermoelectric conversion element 5Pn, the first and second insulating layers 6a and the contact layer 7L are interposed.

  The first and second insulating layers 6a and 6b are arranged so as to be in surface contact with the adjacent n-type plate-like thermoelectric conversion elements 5Pn. The contact layer 7L is a wiring layer in which a wiring pattern is formed by a conductive member. The contact layer 7L is disposed between the first and second insulating layers 6a and 6b and connects the adjacent n-type plate thermoelectric conversion elements 5Pn to each other. Electrically connected.

  Here, in the thermoelectric conversion module 10 </ b> H of the ninth embodiment, the thickness t of each n-type plate-shaped thermoelectric conversion element 5 </ b> Pn is configured to gradually increase along the stacking direction X. More specifically, the thickness t increases in the stacking direction X for every two n-type plate-like thermoelectric conversion elements 5Pn. Therefore, the area of the side surface 5s parallel to the arrows X and Y that function as the heat receiving surface of each n-type plate-like thermoelectric conversion element 5Pn gradually increases in the stacking direction X.

  The thermoelectric conversion module 10H of the ninth embodiment is attached to the heat source pipe 30 and generates electric power in the same manner as the thermoelectric conversion module 10G of the eighth embodiment. Specifically, the thermoelectric conversion module 10H of the ninth embodiment is attached to the heat source pipe 30 so that the stacking direction X coincides with the fluid flow direction in the heat source pipe 30 and the upper surface 10u is in surface contact. In addition, the refrigerant | coolant piping 40 is arrange | positioned similarly to the thermoelectric conversion module 10G of the said 8th Embodiment on the lower surface 10b of the thermoelectric conversion module 10H of 9th Embodiment.

  If it is the thermoelectric conversion module 10H of 9th Embodiment, it will be suppressed from the waste of electrical energy arising between each n-type plate-shaped thermoelectric conversion element 5Pn resulting from the temperature distribution in the heat source piping 30. FIG. Therefore, according to the thermoelectric conversion module 10H of the ninth embodiment, it is possible to obtain higher power generation efficiency than a unileg type stacked thermoelectric conversion module in which plate-shaped thermoelectric conversion elements having a uniform thickness are stacked.

J. Variation:
J1. Modification 1:
In each of the above embodiments, the refrigerant pipe 40 is attached to each thermoelectric conversion module 10, 10 </ b> A to 10 </ b> H so that the refrigerant flows in the direction opposite to the fluid flow direction in the heat source pipe 30. On the other hand, the refrigerant pipe 40 may be attached to each of the thermoelectric conversion modules 10, 10A to 10H so that the flow direction of the refrigerant coincides with the flow direction of the fluid in the heat source pipe 30. The flow direction of the refrigerant in the refrigerant pipe 40 may be determined regardless of the flow direction of the fluid in the heat source pipe 30. However, it is desirable that the temperature gradient in the refrigerant pipe 40 is negligibly small with respect to the temperature gradient in the heat source pipe 30. Further, when each power generation module is attached to the heat source pipe 30, the refrigerant pipe 40 may not be attached. However, it is desirable that the temperature of the heat source pipe 30 is sufficiently higher than the environmental temperature. Each thermoelectric conversion module 10, 10 </ b> A to 10 </ b> H may be provided with a heat exchanger such as an air cooling fin instead of the refrigerant pipe 40.

J2. Modification 2:
In each of the thermoelectric conversion modules 10 and 10A to 10E of the first to sixth embodiments, the thermoelectric conversion elements 5n and 5p are connected in series by a conductive path that is folded back and forth in the first plane direction X. It had been. On the other hand, in each of the thermoelectric conversion modules 10 and 10A to 10E of the first to sixth embodiments, the thermoelectric conversion elements 5n and 5p are turned back so as to reciprocate a plurality of times in the second plane direction Y. They may be connected in series by a route. The wiring configuration for connecting the thermoelectric conversion elements 5n and 5p is not particularly limited, and the thermoelectric conversion elements 5n and 5p may be connected in series. The thermoelectric conversion modules 10 and 10A to 10E of the first to sixth embodiments may have a configuration in which a plurality of groups in which the thermoelectric conversion elements 5n and 5p are connected in series are connected in parallel.

J3. Modification 3:
In the thermoelectric conversion module 10D of the fifth embodiment, the heat receiving area of the p-type thermoelectric conversion element 5p is gradually increased in the first plane direction X, whereas the heat receiving power of the n-type thermoelectric conversion element 5n. The area was uniform regardless of the arrangement position. In contrast, in the thermoelectric conversion module, the heat receiving area of the n-type thermoelectric conversion element 5n gradually increases along the first plane direction X, and the heat receiving area of the p-type thermoelectric conversion element 5p is uniform regardless of the arrangement position. You may be comprised so that it may become. Further, the heat receiving area of the p-type thermoelectric conversion element 5p gradually increases along the first plane direction X, whereas the heat receiving area of the n-type thermoelectric conversion element 5n may be configured to gradually decrease. . Alternatively, conversely, the heat receiving area of the n-type thermoelectric conversion element 5n gradually increases along the first plane direction X, whereas the heat receiving area of the p-type thermoelectric conversion element 5p is gradually reduced. May be. These designs may be appropriately determined according to the temperature characteristics of the constituent materials of each thermoelectric conversion element, the installation environment, and the like.

J4. Modification 4:
In the thermoelectric conversion modules 10 and 10A to 10D of the first to fifth embodiments, the metal member 9 may be provided similarly to the thermoelectric conversion module 10E of the sixth embodiment. Further, in the thermoelectric conversion module 10H of the ninth embodiment, the metal member 9 may be provided similarly to the thermoelectric conversion module 10G of the eighth embodiment.

J5. Modification 5:
The thermoelectric conversion module 10H according to the ninth embodiment includes only the n-type plate-like thermoelectric conversion element 5Pn as the thermoelectric conversion element. On the other hand, the thermoelectric conversion module 10H of the ninth embodiment may be configured to include only the p-type plate-like thermoelectric conversion element 5Pp as the thermoelectric conversion element.

J6. Modification 6:
The thermoelectric conversion module of each of the above embodiments is attached to the heat source pipe 30 through which the high-temperature fluid flows. On the other hand, the thermoelectric conversion module of each said embodiment may be attached with respect to other extending members other than the heat source piping 30. FIG. The thermoelectric conversion module of each of the above embodiments is extended from a heating element and has a temperature distribution in which the temperature decreases as the distance from the heating element increases, and the thermoelectric conversion element having a larger heat receiving area is downstream from the heating element. It only has to be attached so as to be located on the side. For example, the thermoelectric conversion module of each of the above embodiments may be attached to the outer surface of a metal rod-like member connected to a heating element such as an internal combustion engine or an incinerator.

J7. Modification 7:
In the thermoelectric conversion module of each of the above embodiments, the heat receiving area of each thermoelectric conversion element 5p, 5n is configured to gradually increase in the direction from the upstream side to the downstream side of the heat source pipe 30. Smaller parts were not included. On the other hand, a part where the heat receiving area becomes small may be included in the middle of the arrangement direction of the thermoelectric conversion elements 5p and 5n. In the thermoelectric conversion module, when the thermoelectric conversion elements constituting the thermoelectric conversion module are divided into a plurality of groups each having a predetermined number in a predetermined arrangement direction, the average heat receiving area in each group is sequentially increased in the predetermined arrangement direction. It only has to be.

  The present invention is not limited to the above-described embodiments, examples, and modifications, and can be realized with various configurations without departing from the spirit thereof. For example, the technical features in the embodiments, examples, and modifications corresponding to the technical features in each embodiment described in the column of the summary of the invention are the above-described problems, the downsizing of the device, the ease of manufacture, In order to solve part or all of the issues such as improvement of usability, cost reduction, resource saving, etc., or to achieve part or all of the above effects, replacement or combination is performed as appropriate. Is possible. Further, if the technical feature is not described as essential in the present specification, it can be deleted as appropriate.

DESCRIPTION OF SYMBOLS 1, 2 ... 1st and 2nd ceramic substrate 5n ... n-type thermoelectric conversion element 5Pn ... n-type plate-shaped thermoelectric conversion element 5p ... p-type thermoelectric conversion element 5Pp ... p-type plate-shaped thermoelectric conversion element 5c ... thermoelectric conversion element pair 5u ... Upper surface 5b ... Bottom surface 6 ... Insulating members 6a, 6b ... Insulating layer 7 ... Contact member 7L ... Contact layer 8 ... Power line 9 ... Metal members 10, 10A to 10H ... Thermoelectric conversion module 10u ... Upper surface 10b ... Lower surface 20 ... External Load 30 ... Heat source piping 40 ... Refrigerant piping

Claims (7)

A thermoelectric conversion module,
The heat receiving surface for receiving heat is arranged in a predetermined arrangement direction with the heat receiving surfaces facing in the same direction, and includes a plurality of thermoelectric conversion elements electrically connected in series,
The plurality of thermoelectric conversion elements include at least one of an n-type thermoelectric conversion element and a p-type thermoelectric conversion element,
At least one of the n-type thermoelectric conversion element or the p-type thermoelectric conversion element is:
The heat receiving area, which is the area of the heat receiving surface, is arranged so as to gradually increase along the arrangement direction,
When disposed on the surface of the stretching member that is stretched from the heating element and has a temperature distribution in which the temperature decreases with increasing distance from the heating element, the heat receiving surface is disposed so as to face the surface of the stretching member, A thermoelectric conversion module arranged such that the larger the heat receiving area is, the more the heat receiving area is located on the downstream side when viewed from the heating element. The thermoelectric conversion module according to claim 1,
At least one of the n-type thermoelectric conversion element or the p-type thermoelectric conversion element is a thermoelectric conversion module arranged so that the heat receiving area increases for each arrangement position along the arrangement direction. The thermoelectric conversion module according to claim 1 or 2, wherein
The plurality of thermoelectric conversion elements extend in parallel with each other with the heat receiving surface as a bottom surface,
At least one of the n-type thermoelectric conversion element and the p-type thermoelectric conversion element is located on the downstream side in the direction in which the heat receiving area increases in the arrangement direction as the height with respect to the heat receiving surface is smaller. Thermoelectric conversion modules arranged in The thermoelectric conversion module according to any one of claims 1 to 3, wherein
The plurality of thermoelectric conversion elements includes a plurality of pairs of thermoelectric conversion elements having a pair of n-type thermoelectric conversion elements and p-type thermoelectric conversion elements arranged adjacent to each other in the arrangement direction,
The plurality of sets of thermoelectric conversion element pairs are thermoelectric conversion modules in which the heat receiving areas An and Ap of the n-type conversion element and the p-type conversion element are gradually increased along the arrangement direction. The thermoelectric conversion module according to claim 4, wherein
In each of the plurality of pairs of thermoelectric conversion elements, the heat receiving area An of the n-type thermoelectric conversion element and the heat receiving area Ap of the p-type thermoelectric conversion element are different from each other. The thermoelectric conversion module according to claim 5, wherein
A rate of change of the heat-receiving area An of the n-type thermoelectric conversion element according to the arrangement position in the arrangement direction, and a rate of change of the heat-receiving area Ap of the p-type thermoelectric conversion element according to the arrangement position in the arrangement direction; Are different from each other, thermoelectric conversion module. The thermoelectric conversion module according to any one of claims 1 to 6, wherein
The plurality of thermoelectric conversion elements are a plurality of first thermoelectric conversion elements,
Next to the row of the plurality of first thermoelectric conversion elements, a plurality of second thermoelectric conversion elements arranged to correspond to each of the plurality of first thermoelectric conversion elements are arranged in the arrangement direction. Has been
The second thermoelectric conversion element is a p-type thermoelectric conversion element when the adjacent first thermoelectric conversion element is an n-type thermoelectric conversion element, and the adjacent first thermoelectric conversion element is a p-type thermoelectric conversion element. In the case of a conversion element, it is an n-type thermoelectric conversion element,
In the set of the adjacent first and second thermoelectric conversion elements, the heat receiving area An of the n-type thermoelectric conversion element and the heat receiving area Ap of the p-type thermoelectric conversion element are:
An / Ap = {(ρn / κn) · (κp / ρp)} ^1/2
(Κn and κp are the thermal conductivity in the n-type thermoelectric conversion element or the p-type thermoelectric conversion element, respectively, and ρn and ρp are the volume resistivity in the n-type thermoelectric conversion element or the p-type thermoelectric conversion element, respectively. )
The thermoelectric conversion module that satisfies the above relationship.

Images