JP2013157437A - Thermoelectric generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermoelectric generator utilizing the Seebeck effects with which performance reduction of an overall module caused by a failure of a P-type, N-type semiconductor parts can be suppressed and output can be improved.SOLUTION: P-type, N-type semiconductor parts 30, 40 of a thermoelectric generator include first P-type, N-type semiconductors 310, 410 of which one-side terminals 312, 412 are connected to a heat receiving part 10 and the other-side terminals 314, 414 are connected to a heat radiating part 20, and second P-type, N-type semiconductors 320, 420 of which one-side terminals 322, 422 are connected to the heat receiving part 10 and the other-side terminals 324, 424 are connected to the heat radiating part 20. Thus, even in the case where one of two, three or more of semiconductors disposed in parallel fails, energy conduction between one terminal and the other terminal of the semiconductor part can be ensured by the other semiconductor. Furthermore, the heat radiating part 20 is configured into a flexible electrode including a cavity and a fluorine-based inert liquid may be used for a low temperature fluid so as to conduct boiling heat transfer with the cavity.

Description

  The present invention relates to a thermoelectric power generation device that includes a P-type semiconductor and an N-type semiconductor bonded to each other, and generates electric energy based on a temperature difference between both ends thereof, and relates to a thermoelectric conversion device using a so-called Seebeck effect. .

  One of the methods for effectively using waste heat from energy conversion devices is electric regeneration from waste heat. The following thermoelectric generators are known as devices for the electrical regeneration. The thermoelectric generator has a P-type semiconductor part having one end connected to the heat receiving part and the other end connected to the heat radiating part, and an N type having one end connected to the heat receiving part and the other end connected to the heat radiating part. And a semiconductor part. That is, the thermoelectric generator is a thermoelectric converter that utilizes the so-called Seebeck effect.

  In this thermoelectric generator, the heat receiving portion receives heat from the high temperature fluid, while the heat radiating portion radiates heat to the low temperature fluid. This causes a temperature difference between one end and the other end of the P-type semiconductor portion and the N-type semiconductor portion. Based on this temperature difference, electrical energy is generated.

  The generated electrical energy increases as the temperature difference increases. Therefore, it is preferable to increase the temperature difference when improving the power generation efficiency. A technical approach for this is described in Patent Document 1 below.

US Pat. No. 5,737,923

  According to the thermoelectric conversion device described in Patent Document 1, a high-temperature fluid is introduced into a heat receiving part in a gaseous state and condensed in the heat receiving part, whereby the heat receiving part receives heat. On the other hand, the low-temperature fluid is introduced into the heat radiating portion in a liquid state and evaporated at the heat radiating portion, so that the heat radiating portion radiates heat. That is, the heat transfer forms in the heat receiving part and the heat radiating part are accompanied by respective phase changes of the high temperature hot fluid and the low temperature fluid.

  In general, in convective heat transfer, the amount of heat transfer in a heat transfer mode that accompanies a phase change (that is, condensation heat transfer and boiling heat transfer) is significantly larger than that that does not involve phase change. Therefore, the heat transfer resistance to one end of the P and N type semiconductor parts is reduced by the condensed heat transfer in the heat receiving part. Similarly, the heat transfer resistance from the other end of the P, N type semiconductor portion is reduced by boiling heat transfer in the heat radiating portion. For this reason, the temperature at one end of the P and N type semiconductor part may approach the temperature of the high temperature fluid, and the temperature at the other end of the P and N type semiconductor part may approach the temperature of the low temperature fluid.

  As a result, the temperature gradient with respect to the distance from the one end to the other end increases. That is, the temperature difference can be large, and improvement in power generation efficiency is expected as compared with a heat transfer mode without phase change.

  By the way, in general, the P and N type semiconductor parts in the thermoelectric conversion device are used in a stacked module alternately and in series. In this case, when at least one section of the P-type semiconductor portion or the N-type semiconductor portion fails for some reason, the energy conduction in the module is cut off due to the alternate and serial stacking. As a result, the performance of the entire module may be greatly deteriorated.

  In particular, when the temperature difference between one end and the other end of the P, N semiconductor portion is large as in the thermoelectric conversion device described in Patent Document 1, the thermal distortion of the P, N semiconductor portion also increases. For this reason, there is a high possibility of mechanical failure of the P and N semiconductor parts. Therefore, in the thermoelectric conversion device configured to increase the temperature difference, there is a problem that the frequency of performance degradation of the entire module due to failure increases. In the technique described in Patent Document 1 as well, no countermeasures against this problem have been taken.

  Therefore, an object of the present invention is to allow a large temperature difference between one end and the other end of the P, N type semiconductor part, and to suppress degradation of the performance of the entire module due to a failure of the P, N type semiconductor part. It is to provide what you get.

  The present invention includes a heat receiving portion that receives heat from a high temperature fluid, a heat radiating portion that radiates heat to a low temperature fluid, a P-type semiconductor portion having one end connected to the heat receiving portion and the other end connected to the heat radiating portion, and one end receiving the heat receiving portion. And an N-type semiconductor portion connected to the heat radiating portion at the other end, and the heat transfer form in the heat receiving portion or the heat radiating portion is configured to involve a phase change of the high-temperature fluid or the low-temperature fluid. The present invention is applied to a thermoelectric power generation device (a so-called thermoelectric conversion device using the Seebeck effect) that generates electric energy based on a temperature difference between one end and the other end of the semiconductor portion and the N-type semiconductor portion.

  Here, the high temperature fluid means a fluid having a bulk temperature higher than that of the low temperature fluid.

  A feature of the thermoelectric generator according to the present invention is that a P-type semiconductor portion is parallel to at least a first P-type semiconductor having one end connected to a heat receiving portion and the other end connected to a heat dissipation portion, and the first P-type semiconductor. And a second P-type semiconductor having one end connected to the heat receiving portion and the other end connected to the heat radiating portion. The N type semiconductor portion has at least one end connected to the heat receiving portion and the heat radiating. A first N-type semiconductor connected to the first portion, and a second N-type semiconductor disposed in parallel to the first N-type semiconductor, having one end connected to the heat receiving portion and the other end connected to the heat radiating portion. It is in.

  According to this, in the P-type semiconductor part, even if one of the first or second P-type semiconductors fails, the other can ensure energy conduction between one end and the other end of the P-type semiconductor part. . Similarly, in the N-type semiconductor unit, even if one of the first or second N-type semiconductors fails, energy conduction between one end and the other end of the N-type semiconductor unit can be ensured by the other.

  By increasing the number of parallel P and N semiconductors, it is possible to secure energy conduction due to a partial failure.

  Therefore, for example, when the P-type semiconductor portion and the N-type semiconductor portion having the above configuration are alternately and serially stacked to form a module, conduction is cut off even when a failure occurs in the semiconductor. Things can be greatly reduced. For this reason, the performance fall as the whole module can be suppressed. On the other hand, the heat transfer in the heat receiving part or the heat radiating part is in a heat transfer form accompanied by a fluid phase change. For this reason, the temperature difference between the one end and the other end of the P and N semiconductor parts can be increased, and the power generation efficiency can be increased.

  As described above, according to the above configuration, the temperature difference can be increased, and the performance degradation of the entire module due to the failure of the P and N type semiconductor units can be suppressed.

  Further, in the thermoelectric power generation device according to the present invention, the heat radiating section is configured to achieve heat radiation by accompanying vaporization of the low temperature fluid, in order to return the vaporized low temperature fluid to the heat radiating section in a liquefied state. It is preferable that a condensing unit for condensing and liquefying is further provided.

  According to the said structure, the low temperature fluid once vaporized in the heat radiating part can be utilized in a heat radiating part again through condensate liquefaction. That is, the circulation system of the low temperature fluid can be configured as a circulation system, and release of the low temperature fluid to the outside of the system can be prevented.

  In addition, when the low-temperature fluid is condensed and liquefied in the condensing part, condensation latent heat is generated. This condensation latent heat is equivalent to the vaporization latent heat in the heat radiating section. That is, the amount of heat corresponding to latent heat is transported from the heat radiating unit to the condensing unit. Therefore, for example, the degree of freedom for effectively using the heat of condensation of the low-temperature fluid can be increased, such as installing the condensing unit in the heat requesting unit.

  In the thermoelectric generator according to the present invention, the low-temperature fluid is preferably a fluorine-based inert liquid. The boiling point of the fluorinated inert liquid can be adjusted around 30 to 60 ° C.

  By the way, generally, in an energy converter such as a fuel cell or an engine, a large amount of low-temperature waste heat having a temperature of about 80 to 110 ° C. is generated as waste heat. When this low-temperature waste heat is transferred to the heat receiving unit as heat of the high-temperature fluid, the temperature on the heat radiating unit side is assumed to be lower than the low-temperature waste heat. Therefore, it can be said that the temperature on the heat radiating portion side is easily matched with the boiling point of the above-described fluorine-based inert liquid. That is, by using a fluorinated inert liquid as the low temperature fluid, the low temperature waste heat of the energy converter can be used on the high temperature fluid side.

  The said structure is based on this knowledge. According to this, since the low-temperature waste heat of the energy converter can be used as a drive source for power generation, a large amount of low-quality heat can be converted into electricity. For this reason, the efficiency of the whole system can be improved by being introduced into the system including the energy converter.

  In addition, since the fluorinated inert liquid is inactive, it has a large electrical insulation property and does not corrode metals. Accordingly, it is possible to configure the heat dissipating part in contact with the fluorinated inert liquid with a metal so that the heat dissipating part has an electrode function. Thereby, the heat transfer resistance between the other end of the P and N semiconductor part and the low temperature fluid can be further reduced. For this reason, the temperature at the other end of the P-type and N-type semiconductor portions can be closer to the temperature of the low-temperature fluid. As a result, the temperature difference can be further increased.

  In the thermoelectric generator according to the present invention, the P-type semiconductor portion and the N-type semiconductor portion are arranged such that one end of the P-type semiconductor portion and one end of the N-type semiconductor portion face each other, and other than the P-type semiconductor portion. The ends and the other end of the N-type semiconductor part are alternately arranged so that the heat receiving part is interposed between one end of the facing P-type semiconductor part and one end of the N-type semiconductor part. Then, connection is made to one end of each of the P and N type semiconductor parts, and the heat radiating part is interposed between the other end of the P type semiconductor part facing the other end of the N type semiconductor part, You may comprise so that the connection with the other end of each of a P and N type semiconductor part may be made. That is, the heat receiving portion, the heat radiating portion, the P-type semiconductor portion, and the N-type semiconductor portion may be configured to form a so-called T-type thermoelectric conversion element.

  According to this, the heat received by the heat receiving part can be directly transferred to one end of the P, N type semiconductor part, and the heat from the other end of the P, N type semiconductor part can be directly transferred to the heat radiating part. Can communicate. For this reason, the heat transfer resistance between the high-temperature fluid (low-temperature fluid) and one end (the other end) of the P or N type semiconductor part can be reduced.

  Further, in the thermoelectric generator according to the present invention, the low-temperature fluid is a fluorine-based inert liquid, and the heat radiating part is made of a material having a gap, so that the other end of the facing P-type semiconductor part and It is configured to allow the penetration of the fluorine-based inert liquid between the other ends of the N-type semiconductor part, and is configured to achieve heat dissipation by accompanying the vaporization of the fluorine-based inert liquid. In order to return the fluorinated inert liquid to the heat radiating part in a liquefied state, it is preferable to further include a condensing part for condensing and liquefying.

  According to this, the space | gap of a thermal radiation part exists between the other end of the P-type semiconductor part which faces, and the other end of an N-type semiconductor part. Through this void, the fluorine-based inert liquid can enter toward the other end of the P-type semiconductor portion and the other end of the N-type semiconductor portion. Accordingly, the fluorinated inert liquid can approach these other ends and can transfer heat directly from each other end. For this reason, since thermal resistance can be suppressed during heat transfer, the temperature at the other end of the P and N type semiconductor parts can be closer to the temperature of the low temperature fluid. As a result, the temperature difference can be further increased.

  In addition, the presence of voids in the heat radiating part can exhibit elasticity in the heat radiating part. For this reason, for example, when a stress is generated in the P, N type semiconductor part based on a thermal load or external vibration, the stress can be relieved by the elasticity of the heat radiation part. Therefore, even when the stress as described above occurs, the connection between the other end (one end) of the P and N type semiconductor portion and the heat radiating portion (heat receiving portion) can be maintained. As a result, energy conduction between one end and the other end of the P and N type semiconductor portions can be ensured.

  The heat receiving part, the heat radiating part, the P-type semiconductor part, and the N-type semiconductor part may be configured to form a π-type thermoelectric conversion element. According to this, since the element structure can be simply configured, the manufacturing cost can be reduced.

  According to the present invention, the temperature difference between one end and the other end of the P, N type semiconductor part can be made large, and the performance degradation of the entire module due to the failure of the P, N type semiconductor part can be suppressed.

It is a figure showing a schematic structure of a thermoelectric power generator concerning a 1st embodiment of the present invention. It is a figure for demonstrating the detail of the thermoelectric conversion element shown in FIG. It is a figure which shows schematic structure of the thermoelectric power generating apparatus which concerns on 2nd Embodiment of this invention.

DESCRIPTION OF SYMBOLS 1 Thermoelectric power generation device 10 Heat receiving part 20 Heat radiation part 24 Air gap 30 P type semiconductor part 32 One end 34 Other end 40 N type semiconductor part 42 One end 44 Other end 50 High temperature fluid passage 60 Low temperature fluid passage 70 Condensing part 82 Sealed space 310 1st P type Semiconductor 312 One end 314 Other end 320 Second P-type semiconductor 322 One end 324 Other end 410 First N-type semiconductor 412 One end 414 Other end 420 Second N-type semiconductor 422 One end 424 Other end

  Embodiments of a thermoelectric generator according to the present invention will be described below with reference to the drawings.

(First embodiment)
FIG. 1 is a diagram showing a thermoelectric generator 1 according to a first embodiment of the present invention. The thermoelectric generator 1 includes a heat receiving unit 10, a heat radiating unit 20, a P-type semiconductor unit 30, and an N-type semiconductor unit 40.

  Each of the heat receiving portions 10 is formed in a rectangular plate shape, and the tip portion 12 thereof is disposed so as to be positioned in the high temperature fluid passage 50. The member which comprises the plate of the heat receiving part 10 is a metal which is easy to conduct heat and electricity. Here, the high-temperature fluid flowing through the high-temperature fluid passage 50 is a coolant medium that circulates between the vehicle engine and the radiator, and has a temperature of around 110 ° C. That is, in the heat receiving part 10, the front-end | tip part 12 has a function of the fin which receives heat from a high temperature fluid.

  Each of the heat radiating portions 20 is formed in a rectangular plate shape, and the tip portion 22 thereof is disposed so as to be positioned in the low temperature fluid passage 60. The member which comprises the plate of the thermal radiation part 20 is a metal which is easy to conduct | electrically_connect a heat | fever and electricity. Here, the cryogenic fluid flowing through the cryogenic fluid passage 60 is a fluorine-based inert liquid and has a boiling point of 30 to 60 ° C. That is, in the heat radiating part 20, the tip part 22 has a function of a fin that radiates heat to the low temperature fluid.

  Furthermore, these plate-shaped heat receiving portions 10 and heat radiating portions 20 are alternately arranged one by one in the plate surface direction.

  The P-type semiconductor unit 30 is interposed every other gap between the heat receiving unit 10 and the heat radiating unit 20. One end 32 of the P-type semiconductor unit 30 is connected to the opposite side of the tip 12 of the heat receiving unit 10 so as to face the plate surface. The other end 34 of the P-type semiconductor unit 30 is connected to the opposite side of the tip 22 of the heat radiating unit 20 so as to face the plate surface.

  The N-type semiconductor part 40 is interposed in every other gap between the heat receiving part 10 and the heat radiating part 20 and in a gap where the P-type semiconductor part 30 is not interposed. One end 42 of the N-type semiconductor unit 40 is connected to the opposite side of the tip 12 of the heat receiving unit 10 so as to face the plate surface. The other end 44 of the N-type semiconductor unit 40 is connected to the opposite side of the tip 22 of the heat dissipation unit 20 so as to face the plate surface.

  As described above, the P-type semiconductor unit 30 and the N-type semiconductor unit 40 are alternately and serially stacked in the plate surface direction with the heat receiving unit 10 and the heat radiating unit 20 interposed therebetween. The heat dissipation unit 20 also has an electrode function for transmitting electricity generated by the P-type semiconductor unit 30 and the N-type semiconductor unit 40 to the outside.

  That is, the P-type semiconductor unit 30 and the N-type semiconductor unit 40 are alternately arranged so that the one ends 32 and 42 and the other ends 34 and 44 face each other. Here, the heat receiving unit 10 is interposed between the facing ends 32 and 42 and is connected to the ends 32 and 42 of the P and N type semiconductor units 30 and 40, respectively. Further, the heat dissipating part 20 is interposed between the other ends 34 and 44 facing each other, and is connected to the other ends 34 and 44 of the P and N type semiconductor parts 30 and 40, respectively. As described above, the heat receiving unit 10, the heat radiating unit 20, the P-type semiconductor unit 30, and the N-type semiconductor unit 40 form a so-called T-type thermoelectric conversion element.

  The high-temperature fluid passage 50 is partitioned from the laminated structure via the insulating heat insulating portion 52. The insulating heat insulation part 52 insulates and insulates the heat radiation part 20, the P-type semiconductor part 30, the N-type semiconductor part 40, and the high-temperature fluid. The high-temperature fluid passage 50 has an open system so that the liquid medium containing the waste heat flows in from the upstream and the liquid medium flows out to the downstream.

  The low-temperature fluid passage 60 is partitioned from the laminated structure via the insulating heat insulating portion 62. The insulating heat insulation part 62 insulates and insulates the heat receiving part 10, the P-type semiconductor part 30, the N-type semiconductor part 40, and the low-temperature fluid. The low-temperature fluid passage 60 is a sealed circuit, and the fluorine-based inert liquid circulates in the sealed circuit. A liquid transport means 64 is provided in the low temperature fluid passage 60 as a driving source for this circulation.

  In the sealed circuit of the low-temperature fluid passage 60, only a fluorine-based inert liquid and its vapor are present as fluid. That is, there is no non-condensable gas such as nitrogen or oxygen. In forming this sealed system, it is preferable to enclose only the fluorinated inert liquid after evacuating the sealed circuit in advance. Note that the closed system may be formed by filling the cryogenic fluid passage 60 with a fluorine-based inert liquid and suctioning and leaving an appropriate amount.

  Furthermore, the thermoelectric generator according to the present embodiment includes a condensing unit 70. The condensing unit 70 is disposed in the low-temperature fluid passage 60 of the sealed circuit, and is interposed downstream of the heat dissipating unit 20 and upstream of the liquid transport means 64. The condensing step in the condensing unit 70 can be performed quickly. This is based on the absence of non-condensable gas in the closed circuit of the cryogenic fluid passage 60. That is, in the condensing unit 70, factors that prevent diffusion / condensation of the fluorine-based inert liquid vapor are removed in advance.

  FIG. 2 is a diagram for explaining details of the thermoelectric conversion element shown in FIG. 1.

  The P-type semiconductor unit 30 includes a first P-type semiconductor 310 and a second P-type semiconductor 320. The first P-type semiconductor 310 and the second P-type semiconductor 320 are arranged in parallel to the plate surface direction of the heat receiving unit 10 and the heat radiating unit 20. One end 312 of the first P-type semiconductor 310 and one end 322 of the second P-type semiconductor 320 are flush with each other, and constitute one end 32 of the P-type semiconductor unit 30. The other end 314 of the first P-type semiconductor 310 and the other end 324 of the second P-type semiconductor 320 are also flush with each other and constitute the other end 34 of the P-type semiconductor unit 30.

  That is, one end 312 (the other end 314) of the first P-type semiconductor 310 and one end 322 (the other end 324) of the second P-type semiconductor 320 are opposite to the distal end portion 12 of the heat receiving portion 10 (the distal end portion 22 of the heat radiating portion 20). On the side, it is connected to face the plate surface.

  The N-type semiconductor unit 40 includes a first N-type semiconductor 410 and a second N-type semiconductor 420. The first N-type semiconductor 410 and the second N-type semiconductor 420 are arranged in parallel to the plate surface direction of the heat receiving unit 10 and the heat radiating unit 20. One end 412 of the first N-type semiconductor 410 and one end 422 of the second N-type semiconductor 420 are flush with each other, and constitute one end 42 of the N-type semiconductor unit 40. The other end 414 of the first N-type semiconductor 410 and the other end 424 of the second N-type semiconductor 420 are also flush with each other, and constitute the other end 44 of the N-type semiconductor unit 40.

  That is, one end 412 (the other end 414) of the first N-type semiconductor 410 and one end 422 (the other end 424) of the second N-type semiconductor 420 are opposite to the distal end portion 12 of the heat receiving portion 10 (the distal end portion 22 of the heat radiating portion 20). On the side, it is connected to face the plate surface. As described above, the thermoelectric conversion elements forming the T-type thermoelectric conversion elements include the first and second P-type semiconductors 310 and 320 in parallel in the plate surface direction as the P-type semiconductor unit 30 and the N-type semiconductor unit 40. And first and second N-type semiconductors 410 and 420, respectively. Note that the number of parallel P and N semiconductors may be two or more. The above is the description of the configuration of the thermoelectric generator 1 according to the first embodiment.

  Next, the operation of the thermoelectric generator 1 according to the first embodiment configured as described above will be described.

  As the vehicle engine (not shown) is driven, a liquid medium containing waste heat at 110 ° C. flows through the high-temperature fluid passage 50. At the same time, the liquid transport means 64 is driven so that the fluorine-based inert liquid whose boiling point is adjusted to 30 to 60 ° C. flows through the low temperature fluid passage 60.

  Thereby, the heat receiving part 10 receives heat from the liquid medium containing waste heat at the tip part 12. The heat is transferred from the heat receiving unit 10 toward one end 32 of the P-type semiconductor unit 30 and one end 42 of the N-type semiconductor unit 40. The heat transferred to the one ends 32 and 42 is transferred toward the other ends 34 and 44 through the P-type semiconductor unit 30 and the N-type semiconductor unit 40. The heat transferred to the other ends 34 and 44 is transferred toward the tip 22 of the heat radiating section 20. And the heat transmitted to the front-end | tip part 22 of the thermal radiation part 20 is thermally radiated to a fluorine-type inert liquid.

  Here, heat transfer in the heat radiating unit 20 is achieved by introducing a fluorine-based inert liquid in a liquid state and evaporating at the tip 22 of the heat radiating unit 20. That is, the heat transfer mode in the heat radiating unit 20 involves boiling heat transfer. Therefore, the heat transfer resistance from the other ends 34 and 44 of the P and N type semiconductor parts 30 and 40 is reduced by boiling heat transfer in the heat radiating part 20. For this reason, the temperature at the other ends 34 and 44 of the P and N type semiconductor parts 30 and 40 can approach the bulk temperature of the fluorine-based inert liquid.

  Thereby, the temperature gradient with respect to the distance from the said one end 32,42 to the said other end 34,44 becomes large. That is, a large temperature difference occurs between the one ends 32 and 42 and the other ends 34 and 44 in the P-type semiconductor unit 30 and the N-type semiconductor unit 40. As a result, a large amount of electric energy is generated in the P and N type semiconductor units 30 and 40 by the Seebeck effect based on a large temperature difference. The generated electrical energy is extracted from the heat radiating unit 20 having an electrode function and used.

  Further, the fluorine-based inert liquid once vaporized in the heat radiating unit 20 is condensed and liquefied in the condensing unit 70, transported by the liquid transport means 64, and can be used again in the heat radiating unit 20. That is, the circulation system of the fluorine-based inert liquid can be configured as a closed circulation system, and the release of the fluorine-based inert liquid to the outside of the system can be prevented.

  In addition, when the fluorine-based inert liquid condenses into the condensing unit 70, latent heat of condensation is generated. This latent heat of condensation is equivalent to the latent heat of vaporization in the heat radiating section 20. That is, the amount of heat corresponding to latent heat is transported from the heat radiating unit 20 to the condensing unit 70. Therefore, the condensation heat of the fluorine-based inert liquid can be effectively used by installing the condensing unit 70 in the heat requesting unit.

  As described above, since the low-temperature waste heat of the energy converter can be used as a driving source for power generation, a large amount of low-quality heat can be converted into electricity, and the efficiency of the entire system can be improved.

  Incidentally, as described above, since boiling heat transfer occurs in the heat radiating unit 20, a large temperature is generated between the one end 32, 42 and the other end 34, 44 in the P-type semiconductor unit 30 and the N-type semiconductor unit 40. There is a difference. For this reason, the thermal distortion of the P-type semiconductor unit 30 and the N-type semiconductor unit 40 is also large. Furthermore, since the linear expansion coefficient differs between the metal which comprises the heat receiving part 10 and the thermal radiation part 20, and the P-type semiconductor part 30 and the N-type semiconductor part 40, an expansion displacement is also different.

  As a result, a mechanical failure may occur in the P-type semiconductor unit 30 and the N-type semiconductor unit 40. As the mechanical failure here, for example, the end portions 32, 34, 42, 44 in the P-type semiconductor unit 30 and the N-type semiconductor unit 40 are separated from the plate surface of the heat receiving unit 10 or the heat radiating unit 20, A phenomenon in which a crack occurs in the semiconductor unit 30 and the N-type semiconductor unit 40 can be considered.

  In response to the mechanical failure described above, the thermoelectric generator 1 having the above-described configuration exhibits the following operations and effects. In the P-type semiconductor unit 30, even if one of the first or second P-type semiconductors 310 and 320 fails, the other ensures energy conduction between the one end 32 and the other end 34 of the P-type semiconductor unit 30. Can be done. Similarly, in the N-type semiconductor unit 40, even if one of the first or second N-type semiconductors 410 and 420 fails, the N-type semiconductor unit 40 is connected between the one end 42 and the other end 44 by the other. Energy conduction can be ensured. Furthermore, by setting the number of parallel P, N semiconductors to two or more, energy conduction at the time of partial failure is highly secured. Here, energy conduction means electrical conduction and thermal conduction.

  Therefore, the thermoelectric generator 1 having the above configuration is modularized by stacking the P-type semiconductor units 30 and the N-type semiconductor units 40 alternately and in series, but even if a failure occurs in the semiconductor The situation where conduction is interrupted can be greatly reduced. For this reason, the performance fall as the whole module can be suppressed.

  On the other hand, as described above, the temperature difference between the one end 32 and the other end 42 of the P and N semiconductor units 30 and 40 can be increased, and the power generation efficiency can be increased. From the above, according to the thermoelectric generator 1 according to the first embodiment of the present invention, the temperature difference can be made large, and the performance of the entire module is reduced due to the failure of the P and N type semiconductor units 30 and 40. Can be suppressed. The above is the description of the first embodiment of the thermoelectric generator according to the present invention.

(Second Embodiment)
Next, a second embodiment of the thermoelectric generator according to the present invention will be described. This embodiment is different from the first embodiment in the following two points. One is that, instead of the cryogenic fluid passage 60 of the first embodiment, a space for containing a fluorinated inert liquid is formed, and condensation of the fluorinated inert liquid is achieved in the space. . The rest is a material in which the heat dissipating part 20 has a gap instead of the heat dissipating part 20 of the first embodiment being formed in a rectangular plate shape and functioning as a fin for dissipating heat to a low temperature fluid. This is that the fluorine-based inert liquid can enter through the gap.

  Hereinafter, the second embodiment will be described with reference to the drawings only with respect to differences from the first embodiment. In the description of the second embodiment, the same reference numerals as those used in the description of the first embodiment are used for the same or equivalent components as those of the first embodiment. The description is omitted by attaching.

  FIG. 3 is a diagram showing a thermoelectric generator 1 according to the second embodiment of the present invention. This thermoelectric power generator includes a housing 80. The housing 80 surrounds the heat radiating portion 20 side, and its inner wall and the end of the laminated structure are sealed. Thereby, a sealed space 82 defined by the inner wall of the housing 80, the insulating heat insulating part 62, and the heat radiating part 20 is formed inside the housing 80. Further, the housing 80 includes a condensing unit 70 in a part thereof.

  The sealed space 82 is filled with a fluorine-based inert liquid. In the sealed space 82, only a fluorine-based inert liquid and its vapor exist as fluids. That is, there is no non-condensable gas such as nitrogen or oxygen. In forming this closed system, it is preferable to seal only the fluorine-based inert liquid after evacuating the sealed space 82 in advance. Note that the closed system may be formed by filling the cryogenic fluid passage 60 with a fluorine-based inert liquid and suctioning and leaving an appropriate amount.

  The condensing unit 70 includes fins disposed inside and outside the housing 80, and is configured to conduct heat from the inner fins toward the outer fins via the housing 80. With this inner fin, heat exchange between the fin and the vapor of the fluorinated inert liquid is possible, and the vapor is condensed and liquefied. On the other hand, it is possible to dissipate the latent heat of condensation accompanying the condensate liquefaction outside the system with the outer fins. The condensing step in the condensing unit 70 can be performed quickly. This is based on the absence of non-condensable gas in the sealed space 82. That is, in the condensing unit 70, factors that prevent diffusion / condensation of the fluorine-based inert liquid vapor are removed in advance.

  The heat dissipating part 20 is made of a material having a gap 24, and the tip thereof may be flush with, above or below the insulating heat insulating part 62. Examples of the material having the void 24 include, but are not limited to, a metal network structure (for example, a stent or a fiber metal), a metal porous body (for example, a foam metal), a metal particle filler, and the like. Further, the heat dissipating part 20 is interposed between the other ends 34 and 44 facing each other, and is connected to the other ends 34 and 44 of the P and N type semiconductor parts 30 and 40, respectively. As described above, penetration of the fluorine-based inert liquid through the gap 24 between the other ends 34 and 44 of the P and N type semiconductor units 30 and 40 is allowed.

  In the second embodiment, as in the first embodiment, the P-type semiconductor unit 30 and the N-type semiconductor unit 40 are parallel to the plate surface direction of the heat receiving unit 10 in parallel with the first and second P-type semiconductors. 310 and 320, and first and second N-type semiconductors 410 and 420, respectively (not shown). Further, the number of parallel P and N semiconductors may be two or more. The above is the description of the configuration of the thermoelectric generator 1 according to the second embodiment.

  Next, the operation of the thermoelectric generator 1 according to the second embodiment configured as described above will be described.

  The waste heat is transferred to the other ends 34 and 44 through the heat receiving unit 10, the P-type semiconductor unit 30, and the N-type semiconductor unit 40. The heat transferred to the other ends 34 and 44 is transferred toward the heat radiating portion 20. And the heat transmitted toward the heat radiating part 20 is radiated to the fluorine-based inert liquid.

  Here, the air gap 24 of the heat dissipating unit 20 exists between the other end 34 of the P-type semiconductor unit 30 and the other end 44 of the N-type semiconductor unit 40 facing each other. Through this gap 24, the fluorine-based inert liquid enters toward the other ends 34 and 44. Therefore, the fluorine-based inert liquid approaches these other ends 34 and 44, and heat transfer with boiling heat transfer is directly performed. For this reason, since thermal resistance can be suppressed during heat transfer, the temperature at the other ends 34 and 44 of the P and N type semiconductor parts 30 and 40 can be closer to the bulk temperature of the fluorine-based inert liquid.

  The fluorine-based inert liquid once vaporized in the heat dissipating part 20 (the gap 24) can be condensed and liquefied in the condensing part 70 and returned to the heat dissipating part 20 based on its own weight as a liquid. Thereby, it can be utilized in the heat radiation part 20 again. That is, the movement system of the fluorine-based inert liquid can be configured like a heat pipe, and the release of the fluorine-based inert liquid to the outside of the system can be prevented. Therefore, the liquid transporting means 64 such as a pump becomes unnecessary, the apparatus can be driven with power saving, and can be configured compactly.

  In addition, the presence of the air gap 24 in the heat radiating portion 20 can exhibit elasticity in the heat radiating portion 20. For this reason, for example, when stress is generated in the P and N type semiconductor units 30 and 40 based on a thermal load or external vibration, the stress can be relieved by the elasticity of the heat radiating unit 20. That is, the heat radiating part 20 plays a role of a flexible electrode. Therefore, even when the stress described above occurs, the connection between the other ends 34 and 44 (one ends 32 and 42) of the P and N type semiconductor portions 30 and 40 and the heat radiating portion 20 (heat receiving portion 10) is maintained. Can be done. As a result, energy conduction between the one ends 32 and 42 and the other ends 34 and 44 of the P and N type semiconductor units 30 and 40 can be ensured.

  From the above, according to the thermoelectric generator 1 according to the second embodiment of the present invention, as in the first embodiment, the temperature difference can be made large, and the P and N type semiconductor units 30 and 40 The performance degradation of the entire module due to the failure can be suppressed. The above is the description of the second embodiment of the thermoelectric power generator according to the present invention.

  The present invention is not limited to the above embodiments, and various modifications can be employed within the scope of the present invention. For example, in the second embodiment, the housing 80 is configured to have one sealed space 82. Alternatively, the housing 80 may be divided into a plurality of sealed spaces 82. Good. In this case, it is preferable that one sealed space is provided corresponding to each heat radiating portion 20 and that the fluorine-based inert liquid is sealed in each sealed space. Furthermore, it is more preferable that the amount of the fluorine-based inert liquid enclosed in each is made equal. According to this, even when the entire apparatus is tilted, the fluorine-based inert liquid can be uniformly penetrated toward each of the heat radiating portions 20. Therefore, for example, even when the thermoelectric generator 1 is mounted on a moving body such as a vehicle, it is possible to suppress the amount of power generation from being biased for each element. In addition, the inertia force of the fluorine-based inert liquid is suppressed, and the original operability of the vehicle can be maintained.

  In the first and second embodiments, the first and second P-type semiconductors 310 and 320 are arranged in parallel in the P-type semiconductor unit 30 with respect to the plate surface direction. Three or more P-type semiconductors may be arranged in parallel.

  In the first and second embodiments, the first and second N-type semiconductors 410 and 420 are arranged in parallel in the N-type semiconductor portion 40 with respect to the plate surface direction. Three or more N-type semiconductors may be arranged in parallel.

  In the first and second embodiments, the P-type semiconductor units 30 and the N-type semiconductor units 40 are alternately and serially stacked to form a module, and one module is used. Instead of this, for example, a plurality of the stacked modules may be used to be multistaged (parallelized). Compared with the case where the P and N semiconductor units 30 and 40 are scaled up using a single module, the output density of the module multiple units having the same overall size as that of this single module can be higher. In this case, for setting the number of stages in a plurality of modules, for example, it is preferable to create a graph that defines the relationship between the output density and the number of stages and set the number of stages corresponding to the maximum value of the output density in the graph. .

Claims (5)

A heat receiving portion for receiving heat from a high temperature fluid;
A heat dissipating part that dissipates heat to a low-temperature fluid;
A P-type semiconductor portion having one end connected to the heat receiving portion and the other end connected to the heat radiating portion;
An N-type semiconductor portion having one end connected to the heat receiving portion and the other end connected to the heat radiating portion;
With
The heat transfer form in the heat receiving part or the heat radiating part is configured to involve a phase change of the high temperature fluid or the low temperature fluid,
In the thermoelectric generator that generates electrical energy based on the temperature difference between the one end and the other end of the P-type semiconductor portion and the N-type semiconductor portion,
The P-type semiconductor part is
at least,
A first P-type semiconductor having one end connected to the heat receiving portion and the other end connected to the heat radiating portion;
A second P-type semiconductor disposed in parallel with the first P-type semiconductor and having one end connected to the heat receiving portion and the other end connected to the heat dissipation portion;
The N-type semiconductor part is
at least,
A first N-type semiconductor having one end connected to the heat receiving portion and the other end connected to the heat dissipation portion;
A thermoelectric generator, comprising: a second N-type semiconductor disposed in parallel with the first N-type semiconductor, having one end connected to the heat receiving portion and the other end connected to the heat dissipation portion. The thermoelectric generator according to claim 1,
The heat dissipation part is
Configured to achieve the heat dissipation by vaporizing the cryogenic fluid,
A condensing part for condensing and liquefying the vaporized low-temperature fluid in order to condense it into the heat dissipating part in a liquefied state;
A thermoelectric power generator further comprising: In the thermoelectric generator according to claim 1 or 2,
The thermoelectric generator according to claim 1, wherein the low-temperature fluid is a fluorine-based inert liquid. The thermoelectric power generator according to any one of claims 1 to 3,
The P-type semiconductor portion and the N-type semiconductor portion are
The one end of the P-type semiconductor portion and the one end of the N-type semiconductor portion face each other, and the other end of the P-type semiconductor portion and the other end of the N-type semiconductor portion face each other. Alternately arranged,
The heat receiving part is
Interposed between the one end of the P-type semiconductor portion facing the one end and the one end of the N-type semiconductor portion to be connected to the one end of each of the P-type and N-type semiconductor portions;
The heat dissipation part is
It is interposed between the other end of the facing P-type semiconductor part and the other end of the N-type semiconductor part, and is connected to the other end of each of the P-type and N-type semiconductor parts. A thermoelectric power generator configured to be configured as described above. The thermoelectric generator according to claim 4,
The cryogenic fluid is a fluorinated inert liquid,
The heat dissipation part is
By being composed of a material having a void, the fluorine-based inert liquid can be prevented from entering between the other end of the P-type semiconductor portion facing the other end and the other end of the N-type semiconductor portion. Configured to allow, and configured to achieve the heat dissipation by vaporizing the fluorinated inert liquid,
A condensing unit for condensing and liquefying the vaporized fluorine-based inert liquid in a liquefied state to return to the heat radiating unit;
A thermoelectric power generator further comprising: