JP2005223140A - Thermoelectric conversion module and system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent the occurrence of breakdown of thermoelectric elements due to heat or poor bonding of thermoelectric elements and electrodes by suppressing the degradation of thermoelectric conversion efficiency or improving the same. <P>SOLUTION: The thermoelectric conversion module 1 has a plurality of thermoelectric elements 2a connected by a plurality of electrically connecting means 3. In at least one of the thermoelectric elements 2a, the cross section vertical to the X-direction, wherein at least heat or electricity mainly flows in the thermoelectric elements 2a when the thermoelectric module 1 is in operation, is a polygon having three or more angles with at least one of the angles rounded. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a thermoelectric conversion module and a thermoelectric conversion system configured by electrically connecting a plurality of thermoelectric conversion elements.

  The thermoelectric conversion module is a π-type series circuit in which rectangular parallelepiped thermoelectric conversion elements are regularly arranged in a square lattice shape, and the thermoelectric conversion elements are sequentially connected by metal electrode plates.

  Generally, in a thermoelectric conversion module, an insulating substrate is disposed outside a metal electrode plate in order to maintain the structure and maintain heat transport with the outside. Japanese Patent Application Laid-Open No. 2001-119076 discloses that in order to maintain the structure of the thermoelectric conversion module, an insulating resin or the like is provided on the side surface of the thermoelectric conversion element in addition to the insulating substrate outside the metal electrode plate. Yes.

  However, in the thermoelectric conversion module, because the thermoelectric conversion element is fragile, or because the thermal expansion coefficient of the thermoelectric conversion element, the metal electrode plate, the insulating substrate, and the insulating resin is different, thermal stress occurs during use. The thermoelectric conversion element may be broken and the metal electrode plate may be poorly bonded.

  In particular, a high stress is generated in the corner portion of the thermoelectric conversion element as compared with the surrounding area.

  For this reason, there is a thermoelectric conversion module in which the thermoelectric conversion element is formed in a cylindrical shape to prevent local increase in thermal stress.

  However, when the thermoelectric conversion element is simply formed in a cylindrical shape, the filling rate of the thermoelectric conversion element is reduced and the thermoelectric conversion efficiency of the thermoelectric conversion module is reduced as compared with the case of using a rectangular parallelepiped type thermoelectric conversion element. There is a case.

  Japanese Laid-Open Patent Publication No. 11-307828 discloses a thermoelectric conversion device that prevents an insulating substrate and an electrode, and an electrode and a thermoelectric conversion element from being separated due to thermal stress.

In the thermoelectric conversion device disclosed in Japanese Patent Application Laid-Open No. 11-307828, circular or polygonal insulating substrates having 6 or more corners are arranged on both the heat radiation side and the heat absorption side. Thereby, the displacement due to thermal expansion or contraction of the insulating substrate is made uniform in the circumferential direction, and peeling due to thermal stress can be prevented.
Japanese Patent Laid-Open No. 2001-119076 JP-A-11-307828

  Since the thermoelectric conversion module is configured by electrically connecting a large number of thermoelectric conversion elements in series, it does not function normally if connection failure or element destruction occurs even at one location.

  In the above-mentioned thermoelectric conversion device disclosed in JP-A-11-307828, thermal stress caused by a difference in thermal expansion coefficient between the thermoelectric conversion element and the insulating resin on the side surface of the thermoelectric conversion element, the thermoelectric conversion element, and the metal electrode plate It is difficult to reduce the thermal stress caused by the difference in thermal expansion coefficient.

  The present invention has been made in view of the above-described circumstances, and the destruction of the thermoelectric conversion element due to the thermal effect and the poor bonding of the thermoelectric conversion element and the electrode while suppressing the decrease in the thermoelectric conversion efficiency or improving the thermoelectric conversion efficiency. The purpose is to prevent.

  Specific means taken for realizing the present invention will be described below.

  In the first to fifth aspects of the present invention, the thermoelectric conversion module includes a plurality of thermoelectric conversion elements connected by a plurality of electrical connection means.

  In the first aspect, at least one of the plurality of thermoelectric conversion elements has a cross section perpendicular to a direction in which at least one of heat and electricity mainly flows in the thermoelectric conversion element during use having three or more corners. And at least one of the corners has a curvature.

  In the second aspect, at least one of the plurality of thermoelectric conversion elements has at least one straight line having a cross section perpendicular to a direction in which at least one of heat and electricity mainly flows in the thermoelectric conversion element during use. And at least one curve.

  In the third aspect, at least one of the plurality of thermoelectric conversion elements has a curve whose curvature is not constant in a cross section perpendicular to a direction in which at least one of heat and electricity mainly flows in the thermoelectric conversion element during use. including.

  In the fourth aspect, the plurality of thermoelectric conversion elements have a circular cross section perpendicular to the direction in which at least one of heat and electricity mainly flows in the thermoelectric conversion elements during use, and are in close packing. Is arranged.

  In the fifth aspect, a plurality of second thermoelectric conversion elements included in the plurality of thermoelectric conversion elements are disposed in a gap generated when the plurality of first thermoelectric conversion elements included in the plurality of thermoelectric conversion elements are arranged. The at least one of the first thermoelectric conversion element and the second thermoelectric conversion element is different in size and shape.

  In the present invention, it is possible to prevent the thermoelectric conversion elements from being destroyed and the thermoelectric conversion elements and electrodes from being poorly bonded due to thermal effects while suppressing the decrease in thermoelectric conversion efficiency or improving the thermoelectric conversion efficiency.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same elements are denoted by the same reference numerals and description thereof is omitted.

(First embodiment)
In the present embodiment, a thermoelectric conversion module in which a cross section in a direction perpendicular to a direction in which heat mainly flows in a thermoelectric conversion element during use has a square corner has a curvature will be described.

  FIG. 1 is a cross-sectional view showing an example of the configuration of the thermoelectric conversion module according to the present embodiment.

  In FIG. 1, the thermoelectric conversion module 1 is represented by a cross section parallel to a main direction (hereinafter referred to as “X direction”) in which heat flows in the thermoelectric conversion element 2 a during use.

  Note that the X direction may be defined as the axial direction of the thermoelectric conversion element 2a, the joining direction of the thermoelectric conversion element 2a and the electrode 3, and the direction in which current flows in the thermoelectric conversion element 2a.

  The thermoelectric conversion module 1 includes a plurality of thermoelectric conversion elements 2 a, an electrode 3, an insulating substrate 4, and an insulating resin 5. The thermoelectric conversion module 1 may delete at least one of the insulating substrate 4 and the insulating resin 5 from the constituent elements.

  Both ends of the thermoelectric conversion element 2a are connected to other different thermoelectric conversion elements 2a via the electrodes 3, respectively. At both ends of the thermoelectric conversion element 2a, the electrode 3 connects the thermoelectric conversion element 2a in a state shifted by one thermoelectric conversion element 2a. In the present embodiment, the plurality of thermoelectric conversion elements 2a are connected in series, but may be connected in parallel.

  The thermoelectric conversion element 2a, the electrode 3, and the other thermoelectric conversion element 2a have a π-type configuration. The thermoelectric conversion element 2a of the thermoelectric conversion module 1 generates power by the Seebeck effect or dissipates heat or absorbs heat by the Peltier effect.

  A thermoelectric conversion element 2 a is connected to one surface of the electrode 3. An insulating substrate 4 is provided on the other surface of the electrode 3. Further, an insulating resin 5 is provided on a side surface of the thermoelectric conversion element 2a that is not connected to the electrode 3.

  FIG. 2 is a cross-sectional view showing an example of the thermoelectric conversion element 2a.

  FIG. 2 shows a cross section perpendicular to the X direction of the thermoelectric conversion element 2a.

  The cross section perpendicular to the X direction of the thermoelectric conversion element 2a has a square shape with corners having curvature. The radius of curvature is preferably 0.2 mm or more.

  Thus, by giving curvature to the corner of the cross section perpendicular to the X direction of the thermoelectric conversion element 2a, local concentration of thermal stress generated in the thermoelectric conversion element 2a can be avoided, and the thermoelectric conversion element 2a. Can be prevented.

  Further, poor connection and peeling between the thermoelectric conversion element 2a and another member such as the electrode 3 can be prevented. And the highly efficient and reliable thermoelectric conversion module 1 can be provided.

  The cross section perpendicular to the X direction of the thermoelectric conversion element may be a polygonal shape having three or more corners, and at least one of the corners may have a curvature.

  For example, the cross section perpendicular to the X direction of the thermoelectric conversion element may have a rectangular shape with corners having curvature.

  Further, the cross section perpendicular to the X direction of the thermoelectric conversion element may be a polygonal shape having three or more corner portions excluding a rectangle and a square.

  The cross section perpendicular to the X direction of the thermoelectric conversion element may have a shape including at least one straight line and at least one curved line.

  Moreover, the cross section perpendicular | vertical to the X direction of a thermoelectric conversion element is good also as a shape containing the curve whose curvature is not constant.

  Thus, by giving curvature to the cross section perpendicular to the X direction of the thermoelectric conversion element, local concentration of thermal stress generated in the thermoelectric conversion element can be avoided, and the same effect as the thermoelectric conversion element 2a can be obtained. Can be obtained.

(Second Embodiment)
In the present embodiment, a thermoelectric conversion module having a hexagonal cross section perpendicular to the X direction of the thermoelectric conversion element will be described.

  FIG. 3 is a cross-sectional view showing an example of a thermoelectric conversion element provided in the thermoelectric conversion module according to the present embodiment. FIG. 3 shows a cross section perpendicular to the X direction, similar to FIG.

  The cross section perpendicular to the X direction of the thermoelectric conversion element 2b has a hexagonal shape. That is, the thermoelectric conversion element 2b is a hexagonal prism. The corners of the hexagonal cross section may have a curvature.

  In the cross section perpendicular to the X direction, the arrangement of the thermoelectric conversion elements 2b is a close-packed type. In this Embodiment, it arrange | positions so that the side of the cross section of the adjacent thermoelectric conversion element 2b may become parallel.

  Thus, by making the cross section of the thermoelectric conversion element 2b a hexagonal shape, the angle of the corner portion of the cross section becomes larger than that of the conventional square or rectangular cross section thermoelectric conversion element. Can reduce local concentration. In addition, the same effect can be acquired by the same effect | action by making the corner | angular part of the cross section of a thermoelectric conversion element into five or more.

  Moreover, since the arrangement of the thermoelectric conversion elements 2b is a close-packed type, the filling rate of the thermoelectric conversion elements 2b is increased, a decrease in the thermoelectric conversion rate can be prevented, and the thermoelectric conversion rate can be improved.

  Also in this embodiment, it is good also as a shape which chamfered the corner | angular part like the said 1st Embodiment. Thus, in the shape including the chamfered corner, it is preferable that the chamfer C = 0.2 mm or more as described above.

(Third embodiment)
In this embodiment, a close-packed arrangement of thermoelectric conversion elements will be described. In the present embodiment, the cross sections of the thermoelectric conversion elements shown in FIGS. 4 to 6 shown below represent cross sections in a direction perpendicular to the X direction.

  FIG. 4 is a cross-sectional view showing a first example of a close-packed arrangement of thermoelectric conversion elements according to the present embodiment.

  The cross section perpendicular to the X direction of the thermoelectric conversion element 2c is circular. The cross section perpendicular to the X direction of the thermoelectric conversion element may be, for example, elliptical.

  The thermoelectric conversion elements 2c are arranged in a close-packed arrangement by shifting the square lattice arrangement so that the arrangement is staggered. Arbitrary three thermoelectric conversion elements 2c adjacent to each other are arranged such that the centers of the three thermoelectric conversion elements 2c are the vertices of an equilateral triangle.

  Thus, by making the cross section of the thermoelectric conversion element 2c circular, the corner portion of the cross section can be eliminated, and generation of high stress in the corner portion as compared with the periphery thereof can be prevented.

  Further, by making the thermoelectric conversion elements 2c into a close-packed arrangement, the filling rate of the thermoelectric conversion elements 2c can be improved compared to the case where the thermoelectric conversion elements 2c are arranged on a square lattice, and the thermoelectric conversion The thermoelectric conversion efficiency of the module can be improved.

  FIG. 5 is a cross-sectional view showing a second example of a close-packed arrangement of thermoelectric conversion elements according to the present embodiment.

  The cross section perpendicular to the X direction of the thermoelectric conversion element 2d has a triangular shape. The corners of the triangular cross section may have a curvature. By giving the curvature and eliminating the corners of the cross section, it is possible to prevent high stress from occurring in the corners.

  The arrangement of the thermoelectric conversion elements 2d is a square lattice shape, but the adjacent thermoelectric conversion elements 2d are arranged so as to be rotated 180 degrees relative to each other.

  Thereby, the filling rate of the thermoelectric conversion element 2d can be improved, and the thermoelectric conversion efficiency of the thermoelectric conversion module can be improved.

  FIG. 6 is a cross-sectional view showing a third example of the close-packed arrangement of thermoelectric conversion elements according to the present embodiment.

  In FIG. 6, the second thermoelectric conversion element 2 f is arranged in a gap generated when the first thermoelectric conversion element 2 e is arranged.

  In the present embodiment, the cross section of the first thermoelectric conversion element 2e has a square shape with corners having curvature. The cross section of the second thermoelectric conversion element 2f is circular. However, the cross-sectional shape of the first thermoelectric conversion element 2e and the cross-sectional shape of the second thermoelectric conversion element 2f can be freely changed. Moreover, the shape of the cross section of the thermoelectric conversion element may be two or more. Further, a thermoelectric conversion element having the same cross section may be disposed in a gap where a certain thermoelectric conversion element is disposed. Further, thermoelectric conversion elements having the same cross section and different sizes may be arranged in a gap where a certain thermoelectric conversion element is arranged.

  As described above, by disposing another thermoelectric conversion element in a gap where a certain thermoelectric conversion element is disposed, the filling rate of the thermoelectric conversion element can be improved, and the thermoelectric conversion efficiency of the thermoelectric conversion module can be improved. .

  The various thermoelectric conversion elements 2b to 2f described in the second and third embodiments can be applied to the thermoelectric conversion module in the same manner as the thermoelectric conversion element 2a of the first embodiment.

(Fourth embodiment)
In the present embodiment, a power generation system including the thermoelectric conversion module according to each of the above embodiments will be described.

  FIG. 7 is a side view showing an example of the power generation system according to the present embodiment.

  The power generation system 6 is configured by attaching the thermoelectric conversion module 9 described in each of the above embodiments to the heat source unit 7 via the heat conduction unit 8.

  The heat conducting unit 8 propagates heat between the heat source unit 7 and the thermoelectric conversion module 9.

  The thermoelectric conversion module 9 generates power by the temperature difference between the surface that contacts the heat source unit 7 and the other surface via the heat conducting unit 8.

  The heat source unit 7 may be solid, liquid, or gas, and may be either a hot heat source or a cold heat source.

  In the power generation system 6, thermal stress is generated in the thermoelectric conversion module 9 during power generation. However, as described above, the thermal stress in the thermoelectric conversion module 9 is relaxed.

  Further, when the temperature of the heat source unit 7 fluctuates, a thermal cycle occurs in the thermoelectric conversion module 9. However, in the thermoelectric conversion module 9, since thermal stress is suppressed, between the thermoelectric conversion element and the electrode, between the holding body that holds the thermoelectric conversion element on the side surface of the thermoelectric conversion element and the thermoelectric conversion element, in the thermoelectric conversion element , It is possible to suppress the occurrence of cracks and the propagation of the generated cracks.

(Fifth embodiment)
In the present embodiment, an electrical temperature control system including the thermoelectric conversion module described in the first to third embodiments will be described.

  FIG. 8 is a side view showing an example of the electrical temperature control system according to the present embodiment.

  The electrical temperature control system 10 includes an electrical output device 11, a heat conduction unit 8, a thermoelectric conversion module 9, and a temperature control object 12.

  A thermoelectric conversion module 9 is connected to the electrical output device 11. Further, the thermoelectric conversion module 9 is in contact with the temperature control object 12 via the heat conducting unit 8.

  The current from the electrical output device 11 is supplied to the thermoelectric conversion module 9. The thermoelectric conversion module 9 converts the current supplied from the electrical output device 11 into heat. The temperature of the temperature control object 12 changes due to heat dissipation or heat absorption of the thermoelectric conversion module 9.

  Therefore, the temperature of the temperature control object 12 can be controlled by controlling the current supplied from the electrical output device 11 to the thermoelectric conversion module 9.

  The temperature control object 12 may be any of solid, liquid, and gas.

  When the electrical temperature control system 10 is used, thermal stress is generated in the thermoelectric conversion module 9. However, as described above, the thermal stress in the thermoelectric conversion module 9 is relaxed.

  In addition, a thermal cycle occurs in the thermoelectric conversion module 9 due to ON / OFF of the electrical temperature control system 10 and a change in the control temperature. However, in the thermoelectric conversion module 9, since thermal stress is suppressed, between the thermoelectric conversion element and the electrode, between the holding body that holds the thermoelectric conversion element on the side surface of the thermoelectric conversion element and the thermoelectric conversion element, in the thermoelectric conversion element , It is possible to suppress the occurrence of cracks and the propagation of the generated cracks.

  Each of the above-described embodiments is not limited to the above-described configuration as it is, and can be embodied by modifying the constituent elements without departing from the scope in the implementation stage.

  The present invention is effective in the field of performing thermoelectric conversion using a thermoelectric conversion element.

Sectional drawing which shows an example of a structure of the thermoelectric conversion module which concerns on the 1st Embodiment of this invention. Sectional drawing which shows an example of the thermoelectric conversion element with which the thermoelectric conversion module which concerns on the same embodiment is comprised. Sectional drawing which shows an example of the thermoelectric conversion element with which the thermoelectric conversion module which concerns on the 2nd Embodiment of this invention is equipped. Sectional drawing which shows the 1st example of the close-packing type | mold arrangement | sequence of the thermoelectric conversion element which concerns on the 3rd Embodiment of this invention. Sectional drawing which shows the 2nd example of the close-packing type | mold arrangement | sequence of the thermoelectric conversion element which concerns on the same embodiment. Sectional drawing which shows the 3rd example of the close-packing type | mold arrangement | sequence of the thermoelectric conversion element which concerns on the same embodiment. The side view which shows an example of the electric power generation system which concerns on the 4th Embodiment of this invention. The side view which shows an example of the electrical temperature control system which concerns on the 5th Embodiment of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1,9 ... Thermoelectric conversion module, 2a-2f ... Thermoelectric conversion element, 3 ... Electrode, 4 ... Insulating substrate, 5 ... Insulating resin, 6 ... Power generation system, 7 ... Heat source part, 8 ... Heat conduction part, 10 ... Electricity Temperature control system, 11 ... electric output device, 12 ... temperature control object

Claims (11)

In a thermoelectric conversion module comprising a plurality of thermoelectric conversion elements connected by a plurality of electrical connection means,
At least one of the plurality of thermoelectric conversion elements has a polygonal shape in which a cross section perpendicular to a direction in which at least one of heat and electricity mainly flows in the thermoelectric conversion element in use is three or more corners And at least one of the corners has a curvature. The thermoelectric conversion module according to claim 1,
The thermoelectric conversion module according to claim 1, wherein the cross section has a polygonal shape excluding a rectangle and a square. In a thermoelectric conversion module comprising a plurality of thermoelectric conversion elements connected by a plurality of electrical connection means,
At least one of the plurality of thermoelectric conversion elements has at least one straight line and at least one curve having a cross section perpendicular to a direction in which at least one of heat and electricity mainly flows in the thermoelectric conversion element during use. And a thermoelectric conversion module. In a thermoelectric conversion module comprising a plurality of thermoelectric conversion elements connected by a plurality of electrical connection means,
At least one of the plurality of thermoelectric conversion elements includes a curve whose curvature is not constant in a section perpendicular to a direction in which at least one of heat and electricity mainly flows in the thermoelectric conversion element during use. A featured thermoelectric conversion module. In the thermoelectric conversion module according to any one of claims 1 to 4,
The thermoelectric conversion module, wherein the plurality of thermoelectric conversion elements are arranged so as to be closely packed. In a thermoelectric conversion module comprising a plurality of thermoelectric conversion elements connected by a plurality of electrical connection means,
The plurality of thermoelectric conversion elements have a circular cross section perpendicular to a direction in which at least one of heat and electricity mainly flows in the thermoelectric conversion elements during use, and are arranged so as to be closely packed. A thermoelectric conversion module characterized by comprising: In a thermoelectric conversion module comprising a plurality of thermoelectric conversion elements connected by a plurality of electrical connection means,
A plurality of second thermoelectric conversion elements included in the plurality of thermoelectric conversion elements are disposed in a gap generated when the plurality of first thermoelectric conversion elements included in the plurality of thermoelectric conversion elements are disposed; 1. The thermoelectric conversion module according to claim 1, wherein at least one of the thermoelectric conversion element and the second thermoelectric conversion element is different in size and shape. In the thermoelectric conversion system which comprises the thermoelectric conversion module according to any one of claims 1 to 7,
A thermoelectric conversion system comprising a heat source unit to which the thermoelectric conversion module is attached. The thermoelectric conversion system according to claim 8, wherein
A thermoelectric conversion system further comprising a heat conduction means between the thermoelectric conversion module and the heat source unit. In the thermoelectric conversion system which comprises the thermoelectric conversion module according to any one of claims 1 to 7,
A temperature control target part to which the thermoelectric conversion module is attached;
And a means for supplying electricity to the thermoelectric conversion module. The thermoelectric conversion system according to claim 10, wherein
A thermoelectric conversion system further comprising a heat conduction means between the thermoelectric conversion module and the temperature control target unit.

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