JP3312169B2 - How to install thermoelectric generation module - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermoelectric power generation module that directly generates power by utilizing a temperature difference, and more particularly to a mounting structure and a mounting method thereof. INDUSTRIAL APPLICABILITY The present invention is particularly effective when applied to an incinerator power generation system that generates thermoelectricity using waste heat of a general incinerator or the like.

[0002]

2. Description of the Related Art Direct power generation by utilizing a temperature difference
This is conventionally performed by providing a temperature difference between PN junctions of a Bi-Te-based material or the like. Already, these materials have come to be widely marketed in electronic refrigerators and the like that use electric energy to cool in the reverse process of power generation, and are also marketed as modules combining dozens of these PN junctions. Mass production has reduced the cost to one-third of its original cost.

The basic structure of this cooling module is the same,
A thermoelectric power generation module whose heat-resistant temperature has been raised to about 200 ° C. is already on the market in some cases. Many of the power generation systems to which these are applied are described in, for example, Realize Co., Ltd., “Thermoelectric Conversion System Technology Overview” issued on June 30, 1995.

In such temperature difference power generation, if a high-temperature plate connected to a heat source on the high-temperature side and transmitting heat to the power generation module and a low-temperature plate for radiating heat are simply fixed to the power generation module, distortion of the shape due to thermal expansion of the high-temperature plate may occur. It is known that a compressive stress acts on a power generation module to easily break the module. Therefore, the high-temperature plate, the power generation module, and the low-temperature plate are usually fixed using an elastic body such as a spring.

FIG. 21 shows an example of a thermoelectric power generation system using a conventional mounting method. One surface of the thermoelectric generation module 1 is in contact with the high-temperature plate 4 via the heat conductive grease 2a, the alumina plate 3a, and the heat conductive grease 2b, and the other surface is the heat conductive grease 2c, the alumina plate 3b, and the heat conductive grease. Grease 2d
Is in contact with the low-temperature plate 5. The hot plate 4 is a hot heat source 6
In addition, the low-temperature plates 5 are each thermally connected to a low-temperature heat source 7. The high-temperature plate 4 and the high-temperature heat source 6 are surrounded by a hard heat insulating material 8 and a porous heat insulating material 9, and the entire structure is housed in a rigid frame 10. A cap screw 11 is provided through the upper part of the frame 10.
A load cell 12, a flat spring 13, and a guide 14 are arranged in this order below. By lowering the cap screw 11, pressure is applied to the hard insulating material 8 via the steel balls 15, thus fixing the power generation module between the hot plate and the cold plate. The load cell can monitor the axial force by an electric circuit (not shown).

As described above, the conventional method of mounting the power generation module requires a spring and a screw and a rigid frame for guiding and pressing the spring, and further requires a steel ball and a hard heat insulating material for supporting the point. Was needed.

[0007]

The size of a Bi-Te-based power generation module used at about 200 ° C. is limited to about 5 cm square in order to prevent self-destruction due to thermal expansion. Therefore, even the largest one has a power generation capacity of about 10 W. The most important thing in an industrial power generation system is the power generation cost. 1kWh of electricity price
If calculated at 20 yen per unit, the price of the amount of power generated for 5 years at a power generation capacity of 10 W is at most about 9000 yen. However, the conventional fixing method using a spring requires not only the material cost of the spring but also a sturdy frame or the like that supports the spring, and it is impossible to drastically reduce the cost.

In an industrial power generation system, it is important to fix a plurality of power generation modules at the same time to reduce the number of parts as a whole and to reduce the cost. However, the thickness of commercially available power generation modules is ±
There is a variation of about 0.1 mm, and if a plurality of such power generation modules are fixed collectively, heat transfer is poor, and the power generation capacity is significantly reduced.
It was necessary to make the thickness uniform. The additional cost for that is 1
The cost per module was several thousand yen, and the reduction was the most important issue.

The present invention solves such a conventional problem,
It is an object of the present invention to provide a thermoelectric power generation module mounting structure and a mounting method capable of stably fixing a power generation module with a low-cost simple configuration.

[0010]

In order to achieve the above object, a method of mounting a thermoelectric power generation module according to the present invention is arranged between a high-temperature plate serving as a heat source on the heating side and a low-temperature plate serving as a heat source on the cooling side. The thermoelectric power generation module mounting method, wherein the high temperature having a portion of 3 to 15 mm in thickness
A step of preparing a plate, wherein the thermoelectric power generation module includes a plurality of modules having different thicknesses, and an adhesive is applied to one surface of the plurality of modules and pressed against the high-temperature plate or the low-temperature plate, and the other of the plurality of modules is pressed. adhering to match the height of the surface, the hot plate, a step of laminating the thermoelectric power generation module and the cold plate, and a plurality of S
US304 stainless steel M4 screw has the thickness of the hot plate
Only compresses directly part of 3 to 15 mm, and the cold plate and the hot plate of the plurality of SUS304 stainless steel M
It is characterized by having a step of fixing with four screws.

[0011]

[0012]

[0013]

[0014]

[0015]

[0016]

[0017]

[0018]

[0019]

[0020]

Further, according to the method for mounting a thermoelectric power module according to the present invention, there is provided a method for mounting a thermoelectric power module disposed between a high-temperature plate serving as a heat source on the heating side and a low-temperature plate serving as a heat source on the cooling side. Preparing a high-temperature plate having a portion of 3 to 15 mm, wherein the thermoelectric generation module includes a plurality of modules having different thicknesses, and an adhesive is applied to a surface of the high-temperature plate or the low-temperature plate; Is pressed against the surface to which the adhesive has been applied, and the steps of bonding the other surfaces of the plurality of modules with the same height, laminating the high-temperature plate, the thermoelectric power generation module and the low-temperature plate, and A plurality of SUS304 stainless steel M4 screws are used to directly compress the portion of the high-temperature plate having a thickness of 3 to 15 mm, and the high-temperature plate and the low-temperature plate are compressed. It characterized by having a step of fixing by serial plurality of SUS304 stainless steel M4 screws.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In one embodiment of the present invention, a thermoelectric power generation module mounting structure includes a high-temperature plate thermally connected to a high-temperature heat source, a heat conductive grease for improving heat transfer performance, and an electrical insulation. Thin alumina plate, heat conductive grease, thermoelectric generator module, heat conductive grease, heat transfer sheet made of silicone resin to absorb strain due to thermal expansion and electrically insulate, heat conductive grease, low temperature A low-temperature plate thermally connected to a heat source is stacked in this order, and the high-temperature plate and the low-temperature plate are fixed with a plurality of screws.

If the fixing screw is made of the same material as the material of the high-temperature plate, or a material having a very close thermal expansion coefficient, distortion due to the difference in thermal expansion between the high-temperature plate and the screw can be prevented.

In place of the heat transfer sheet made of a silicone resin, a heat conductive sheet based on a fluororubber can be used.

Further, it is preferable that any or all of the above-mentioned layers of the heat conductive grease are replaced with a heat conductive adhesive and bonded and fixed. When an adhesive is used, it is more preferable to use a silicone-based, thermally conductive and soft adhesive as the low-temperature-side adhesive, because thermal expansion distortion is absorbed.

Further, when each member is bonded and fixed with an adhesive, one or both of the high-temperature plate and the low-temperature plate is made of a thermally conductive and electrically insulating material, or an insulating material such as aluminum whose surface is anodized. When the treated metal material is used, the thermoelectric power generation module can be directly adhered to the high-temperature plate or the low-temperature plate without the intermediary of the alumina plate or the heat transfer sheet, which is an electric insulating plate, to improve the heat transfer property.

The use of an adhesive is particularly effective when a plurality of thermoelectric modules are mounted on a single high-temperature plate or low-temperature plate. That is, taking the case of bonding to a high-temperature plate as an example, a hard adhesive is applied to the surface of the high-temperature plate or one surface of each thermoelectric generation module, and each module is collectively applied to the high-temperature plate with a uniform load by a press head. Press and fix. In this way, the difference in thickness between the plurality of thermoelectric power modules having a thickness of about 0.1 mm is adjusted with a hard adhesive, and the other surface (low-temperature surface) of each thermoelectric power module is positioned on the same plane. I do. For this reason, thermoelectric power generation can be performed relatively uniformly in each module, and the polishing step of the module can be omitted, which is preferable. The same applies to the case where the thermoelectric power generation module is first bonded to the low-temperature plate. However, in this case, a soft adhesive can be used.

Further, using a high-temperature plate having a metal surface insulated, a high-temperature plate, a heat conductive grease, a thermoelectric generation module, a heat conductive grease, a heat transfer sheet, a heat conductive grease,
In addition, a structure in which the low-temperature plates are stacked and the high-temperature plates and the low-temperature plates are fixed with a plurality of screws can be employed. This structure is more preferable because the heat transfer performance is improved and the power generation efficiency is improved as compared with the structure insulated by the alumina plate described above. If a material having a metal surface insulated is used as the low-temperature plate, the heat transfer sheet on the low-temperature side can be omitted.

By the way, the following two points are important in the mounting structure of the thermoelectric power generation module.

First, consideration is given to thermal expansion. After assembling the thermoelectric generation module at room temperature, it is used for operation. During actual operation, the temperature of the high-temperature portion rises to around 200 ° C. and the high-temperature portion thermally expands, but the low-temperature portion does not relatively expand. For this reason, when the high temperature part and the low temperature part are fixed, a compressive stress is applied to the module, and the module is easily broken.
(Incidentally, the thermoelectric power generation module HZ-
No. 14 has a nominal allowable compressive stress of 10,000 PSI (70MP
a). ) To prevent this, a flexible mounting structure that absorbs the thermal expansion is required.

Second, heat transfer is considered. In order to improve the power generation efficiency, a structure that realizes uniform heat transfer to all of the plurality of thermoelectric power generation modules and efficiently transfers heat to the thermoelectric power generation module unit is required.

According to the present invention, it is possible to realize a structure in which the problem of thermal expansion and the problem of heat transfer described above are sufficiently taken into consideration, whether the structure is a screwed structure or a bonded structure.

First, the problem of thermal expansion will be described.

As an example, a case where a high temperature plate made of copper having a close thermal expansion coefficient and a fixing screw made of stainless steel SUS304 are combined will be described. The coefficient of linear expansion is copper 16.6 × 10 ⁻⁶ / K SUS304 17.3 × 10 ⁻⁶ / K.

In the Bi-Te type thermoelectric power generation module,
The maximum efficiency is about 5 mm in thickness, and modules having a thickness of about 5 mm are commercially available. Therefore, the thickness of the portion of the high-temperature plate that is fastened by the fixing screw is Xm.
m, the length of the screw is (5 + X) mm. Assuming that the temperature rise of the hot plate is ΔT ° C., the amount of elongation of the fastening portion of the hot plate is (16.6 × 10 ⁻⁶ × X × ΔT). On the other hand, since the fixing screw is in contact with both the high-temperature plate and the low-temperature plate, its temperature distribution is linear, and the effective temperature rise is ΔT ° C./2. Therefore, the amount of elongation of the screw is (17.
3 × 10 ⁻⁶ × (5 + X) × ΔT / 2). When X is obtained assuming that the extension of the fastening portion of the high-temperature plate is equal to the extension of the fixing screw, X is about 5.5 mm. Therefore, the hot plate of copper and S
With the combination of the fixing screws of US304, if the thickness X of the fastening portion of the high-temperature plate is smaller than 5.5 mm, the tightening is loosened at a high temperature, and if it is larger than 5.5 mm, the tightening is reversed at a high temperature. Therefore, by setting the value of X to 5.5 mm or slightly larger, it is possible to suppress the compressive stress applied to the thermoelectric power module to a value equal to or less than the breaking stress.

In this case, the distance between the fixing screws is 60 m.
Assuming that the temperature rise of the hot plate is 200 ° C., the hot plate extends about 120 μm toward each screw in a direction perpendicular to the screw tightening direction, that is, in the in-plane direction of the hot plate.
The amount of elongation of the screw in the axial direction due to the elongation of the hot plate is 1-2.
μm, but the force generated by this is about 50 kg
It is quite large with f. As a structure to relieve these forces,
In the present invention, first, the screw is M4 (JIS B0205-
1982) A screw having the following small cross-sectional area was used to reduce the generated force itself.

Next, the thickness of the thermally conductive grease is set to about 50 μm, an elastic rubber sheet having a thickness of about 200 μm is used as a heat transfer sheet, or a thermally conductive adhesive having a silicone rubber base material is used. The thickness of the material is 30-5
By setting the thickness to 0 μm, the compression strain of several μm to about 20 μm was reduced. For example, when a silicone heat transfer sheet (200 μm thick) is sandwiched between a low-temperature plate and a power generation module, the elasticity of silicone rubber can absorb about 10% of the thickness. 20
The power generation module does not break even if there is a difference of about μm.
Copper and aluminum (linear expansion coefficient 23.
2 × 10 ⁻⁶ / K), SUS304 is used as a fixing screw, and the difference in elongation between the hot plate and the fixing screw when the temperature difference is 200 ° C. is shown in Table 1. If the difference in the amount of elongation is +, the elongation of the screw is larger than that of the high-temperature plate and the tightening is loosened, and if the difference is-, it means that the screw is tightened in the opposite direction. If the difference in the amount of elongation is allowed up to 16 μm in consideration of safety in design, the thickness (thickness of the fastening portion) of the high-temperature plate of aluminum (A3000 series) is 3 to 8 mm. On the other hand, in the case of copper, the allowable thickness of the fastening portion is 6 to 15 mm.

[0038]

[Table 1]

When the high-temperature plate and the fixing screw are made of the same material,
According to the above considerations, the desirable thickness of the fastening portion of the hot plate is about 5 to 5.1 mm.

By employing the adhesive fixing structure, the compressive stress caused by the screwing structure can be reduced.

Next, the problem of heat transfer will be described.

Regarding the heat equalizing structure, in the case of screwing, there is a problem that a force is applied only around the screw. To solve this problem, apply a thicker grease or sandwich a heat transfer sheet between the thermoelectric generator module and the cold plate so that a uniform compressive stress is applied to the module, in other words, a uniform thermal connection. Was done. In addition, uniform heat transfer is further improved by fixing with an adhesive. However, at a low temperature of 200 ° C. or less, an organic elastic adhesive such as silicone is effective, and when the temperature exceeds 200 ° C., an inorganic adhesive having a relatively large thermal expansion coefficient must be used. . This is because a metal or an alloy is often used as the high-temperature plate, and generally the metal has a large thermal expansion coefficient, so that an inorganic adhesive having a small thermal expansion coefficient cannot be joined well. Therefore, when a material having a small coefficient of thermal expansion such as ceramic is used as the high-temperature plate, a general heat-resistant, high-thermal-conductivity inorganic adhesive can be used.

Further, according to the present invention, the electrical insulation performance of the high-temperature plate or the low-temperature plate itself can be reduced, so that the number of the electrical insulating layer, the grease layer, and the adhesive layer can be reduced. And power generation efficiency can be improved.

The electric insulation performance is, for example, 100 V,
A simple performance of about 1 kΩ is sufficient. This is because the power generation voltage of the thermoelectric power generation module is about 1 to 2 V, which is usually connected in series, taken out, and converted into AC by an inverter, so that a withstand voltage of about 100 V is required at most. In addition, since the series internal resistance of the entire power generation module at this time is 20Ω or less, the internal resistance of the external circuit is designed to be 20Ω or less, and the power generation loss can be sufficiently reduced with the insulation performance of about 1 kΩ.

With such a simple insulation performance, generally, it is possible to sufficiently realize the insulation treatment of the insulating thermal conductive grease or the like and the metal surface (the high-temperature plate or the low-temperature plate surface). Further, in a small-scale power generation system of only a few modules, since the internal resistance is 1Ω or less, it is sufficient to use insulating heat conductive grease or the like without surface treatment of a metal (a high-temperature plate or a low-temperature plate). Insulation performance is obtained and power generation is possible, and power generation loss can be reduced by using this as one power generation block and insulating between a plurality of blocks.

[0046]

FIG. 1 is a schematic sectional view of a first reference example of a thermoelectric power module mounting structure which is out of the scope of the present invention. In the structure of this reference example, a high-temperature heat source 6 for thermoelectric power generation is used.
A copper high-temperature plate 4, a thermally conductive grease 2b, which is fixed to and thermally connected with a screw 16 via a thermally conductive grease 2e,
Alumina electrical insulating plate 3a having a thickness of 0.2 mm, thermal conductive grease 2a, thermoelectric power module 1 (HZ-14 manufactured by Hi-Z, USA), thermal conductive grease 2c, electrical insulating thickness of 0. 2 mm heat conductive silicone sheet 17, heat conductive grease 2d, and heat conductive grease 2f
Plate 5 fixed with screws 16 and thermally connected
Are stacked in this order, and the high-temperature plate 4 and the low-temperature plate 5 are screwed with four stainless steel SUS304 M4 screws 18. The periphery on the high temperature side is covered with a heat insulating material 19. Such a structure is prepared in advance with a high-temperature plate thermally connected to the high-temperature heat source and a low-temperature plate thermally connected to the low-temperature heat source, and sequentially stacks the above-described components therebetween. By screwing the hot plate and the cold plate, or by superposing the thermoelectric module and other components and the hot plate as described above on the cold plate thermally connected to the cold heat source, It can be obtained by screwing the plate and then thermally connecting the hot plate to a hot heat source.

FIG. 2 shows a schematic cross section of the thermoelectric power generation module HZ-14 used in this embodiment. In this module, the thermoelectric module for cooling, which is commercially available, uses a low-temperature solder to connect the internal elements, whereas the electric connection between the elements is performed using a thermal spraying technique.
It is designed so that the power generation performance can be improved compared with the melting point of 180 ° C. of the low-temperature solder. 21 is Bi-Te P
An N-junction power generation element assembly, 22 is a metal electrode, 23 is a lead wire, and 24 is a protective resin. The junction aluminum electrode 22 of the internal element is exposed on both the low temperature side and the high temperature side,
Usually, it is used insulated with a thin alumina plate having a thickness of about 0.2 mm.

FIG. 3 is a schematic cross-sectional view illustrating a fastening portion between a high-temperature plate and a low-temperature plate. In FIG. 3, illustration of an alumina insulator, a silicone sheet, heat conductive grease, and the like is omitted. The high-temperature plate 4 is counterbored to form a thin fastening portion 4a having a thickness t, and screwing with the low-temperature plate is performed at this portion. As described above, the thickness of the thin portion 4a is selected in the range of 3 to 15 mm according to the materials of the high-temperature plate 4 and the screw 18. In this embodiment, the thickness of this portion is set to 5.5.
mm, and evenly tighten the four screws 18 with a torque of 15 kgf-
cm.

As the silicone heat transfer sheet, TC-20BG manufactured by Shin-Etsu Chemical Co., Ltd. was used, and as the heat conductive grease, KS613 manufactured by Shin-Etsu Chemical Co., Ltd. having a heat-resistant temperature of 300 ° C. was used.

A K-type sheath thermocouple of 1.6 mm in diameter is inserted into each of the high-temperature plate and the low-temperature plate, at the center of the surface facing the power generation module and at four locations around the power generation module, for a total of five locations at a depth of 5 mm. The temperature difference between the plate and the cold plate can be measured.

The power generation characteristics of the first reference example shown in FIG. 1 were measured. Specifically, a device provided with a slip resistor 25, an ammeter 26, and a voltmeter 27 as shown in FIG. 4 is used while heating a high-temperature heat source and measuring the temperature difference between the high-temperature plate and the low-temperature plate. The power taken from the power generation module was measured while changing the load resistance. FIG. 5 shows the power generation characteristics. FIG. 5 is a plot of the generated current on the horizontal axis and the generated voltage and generated power on the vertical axis. The curves A1, A2, A3, and A4 show that the center temperature difference between the high temperature plate and the low temperature plate is 107.96, 135.00. , 162.8
1, and the generated voltage at 190.71 ° C., B1, B
2, B3 and B4 indicate the generated power at the respective temperature differences. As can be seen from the figure, the maximum power can be obtained when the load resistance is equal to the internal resistance (0.2Ω) of the power generation module. In order to confirm the reproducibility, the temperature of the hot plate was lowered once and the second measurement was performed. However, there was almost no change in the power generation characteristics, and the thermal expansion distortion was absorbed by the structure of this reference example. It was confirmed that it was.

For comparison, the power generation characteristics of the conventional device shown in FIG. 21 were measured. Since thermal expansion occurs with an increase in temperature and the axial force increases, the axial force was adjusted each time to 600 kgf. Otherwise, the first reference
It was measured similar to the considered example. FIG. 6 shows the obtained power generation characteristics. In FIG. 6, curves C1, C2, C3, C4, C
5 is a temperature difference between the hot plate and the cold plate of 104, 130, 1
57, 186, power generation voltage at 201 ° C., D1, D2,
D3, D4, and D5 indicate the generated power at each temperature difference.

FIG. 7 shows the maximum generated power at each temperature difference from the characteristics shown in FIGS. 5 and 6, the horizontal axis represents the center temperature of the hot plate and the low temperature plate, and the vertical axis represents the maximum generated power. is there.
In FIG. 7, a curve E is a characteristic of the first reference example of the present invention, and a curve F is a characteristic of the conventional example. FIG. 7 further shows the maximum power generation characteristic of the second reference example in which the alumina plate on the high-temperature side is removed from the first reference example shown in FIG. A curve H shows the maximum power generation characteristic of the third reference example using an alumina plate instead of the silicone heat transfer sheet on the low temperature side of the reference example.

The electrical insulation performance of only the grease of the second reference example was a performance of 3Ω at 1.5V. Since the internal resistance of the thermoelectric generation module was about 0.2Ω, it was confirmed that sufficient power could be taken out even with this level of insulation performance. It is easily presumed that the performance is equivalent to that obtained by insulating the surface of the metal high-temperature plate or low-temperature plate in the present invention. If long-term reliability is taken into consideration, it is needless to say that insulating treatment of the metal surface is desirable.

FIG. 7 shows that the conventional example has the best characteristics, but that each of the reference examples of the present invention has the same power generation capacity.

FIG. 8 shows a fourth embodiment which is outside the scope of the present invention. This reference example is an example in which alumina plates 3a and 3b are used on both the high-temperature side and the low-temperature side and bonded and fixed with an adhesive. On the high temperature side, inorganic adhesives 28a and 28b are used, and on the low temperature side, organic adhesives 29a and 29b are used. In this case, if the surface of the high-temperature plate or the low-temperature plate or both surfaces are insulated, the alumina plate becomes unnecessary, and the power generation performance is further improved. Even in the case of such double-sided bonding, if a screwing structure is adopted as in the first reference example, if the tensile or compressive force generated by the weight or the like from the whole structure is large between the low-temperature plate and the high-temperature plate, the fixing screw It is effective because it can be supported by. However, when the screwing structure is used together, it is necessary to use a soft adhesive at the low temperature side.
In FIG. 8 and FIG. 9, the illustration of the high-temperature heat source and the low-temperature heat source is omitted.

[0057] A fifth reference example outside the scope of the present invention in FIG. In this reference example, the heat conductive grease 2a, 2b
Is an example in which organic adhesives 29a and 29b are used on the low temperature side. In this case, similarly to the fourth embodiment, if the surfaces of the high-temperature plate and the low-temperature plate are insulated, the alumina insulating plate becomes unnecessary,
The power generation performance is improved. This reference example is effective when there is no adhesive material suitable for bonding the material of the high-temperature plate and the power generation module, and is particularly effective when the temperature of the high-temperature plate is increased, and increases the temperature difference applied to the power generation module. And power generation capacity can be significantly improved.

FIGS. 10A and 10B are schematic views of the first embodiment of the present invention, in which FIG. 10A is a longitudinal sectional view, and FIG. 10B is a transverse sectional view of the thermoelectric power module on its upper surface. In this embodiment, three thermoelectric power generation modules 1a, 1b, 1c are arranged in one row,
The distance between each module is 12 mm, and a total of eight M4
This is an example of fixing with screws 18. The configuration of each thermoelectric generation module and the method of stacking each component are the same as in the first reference example shown in FIG. However, each module has been subjected to a polishing treatment to have a uniform thickness. Electric power was extracted by connecting three thermoelectric power generation modules in series. FIG. 11 shows a power generation characteristic similar to that of FIG. The curves I1, I2, I3, and I4 show that the average value of the temperature differences between the hot plate 4 and the cold plate 5 corresponding to the centers of the three modules is 104, 131, 158, and 184, respectively.
The generated voltage at the time of ° C., J1, J2, J3, and J4 indicate the generated power at each temperature difference. FIG. 12 is a diagram plotting the temperature difference described above on the horizontal axis and the maximum generated power on the vertical axis from FIG. FIG. 13 shows a change with time of the thermoelectric power generation system, in which the horizontal axis represents the number of heat cycles, and the vertical axis represents open-circuit voltage and generated power. Both voltage and power are stable regardless of the number of thermal cycles.

As can be seen from FIGS. 11 to 13, according to the present embodiment, the M4 screw 8 is used for fixing the thermoelectric power generation module.
It can be seen that performance substantially equivalent to that of the conventional power generation system can be stably obtained using the book. When an adhesive is used as in the fourth and fifth reference examples, it is not necessary to make the thickness of each thermoelectric generation module uniform by polishing. In the prior art, when a plurality of such modules are fixed, a structure in which a high-temperature plate or a low-temperature plate is divided and pressed by a spring, a center of a rigid frame and a center of a rigid plate are utilized by spring force.
There is a structure that pushes with a point or a structure that presses the center of each module with a rigid frame evenly using spring force, but the cost of the present invention is much smaller than the cost of these methods. .

FIG. 14 shows an example of an incinerator power generation system employing the thermoelectric power generation module mounting structure of the present invention. After the exhaust gas from the incinerator is passed through an electric dust collector, a combination of a heat collecting fin 32 and a heat receiving portion 33a of a heat pipe 33 is inserted into a flue portion 31 through which clean high-temperature (250 ° C.) exhaust gas is passed. It is transported outside the flue by a pipe, and the heat radiating portion 33b of the heat pipe is used as a high-temperature heat source. The working fluid of the heat pipe uses a fluorine-based refrigerant (FC-40, manufactured by Sumitomo 3M) having a boiling point of 155 ° C., and the internal pressure is 8 k.
It was designed to be suppressed to about gf / cm ² or less. A plurality of fins (diameter of about 50
mm, and a total area of about 0.5 m ² ), so that heat can be efficiently collected from high-temperature exhaust gas.

On the other hand, a water-cooled holder 34 was used as the low-temperature heat source, so that the system could be downsized.

A thermoelectric power generation module 1a, 1b, 1c having a mounting structure according to the present invention between the high-temperature heat source and the low-temperature heat source.
Was installed. The mounting structure of the thermoelectric generation module in the power generation unit 35 of this embodiment is the structure of the sixth embodiment shown in FIG. The tightening torque of the mounting screw of the thermoelectric generation module was 25 kgf-cm.

Although not shown in detail in FIG. 14, at the end of assembly, the power generation unit 35 and the high-temperature heat pipe are covered with a heat insulating material 36 to reduce heat loss.

The power generation system includes four sets each including the heat collection heat pipe, the power generation unit, and the water cooling holder.
The power output is obtained by connecting these power generation units in series.

FIG. 15 shows the power generation characteristics of this thermoelectric power generation system.
20 to FIG.

FIG. 15 shows the characteristics of each of the four power generation units, and FIG. 16 shows the characteristics of the total output obtained by connecting the power generation units in series. The measurement conditions of these characteristics are a stack temperature of 250 ° C., a wind speed of 17 m / s, a cooling water flow rate of 2.5 l / min, and a cooling water temperature of 10 ° C.

FIG. 17 shows the characteristics of the four power generation units when the flue temperature was raised to 270 ° C.
Indicates the characteristics of the total output in which the power generation units are connected in series. Other measurement conditions are the same as those in FIGS.

FIG. 19 shows the temperature dependence of the open-circuit voltage and the maximum generated power when the wind speed is constant at 17 m / s.
0 indicates the temperature dependence of the open-circuit voltage and the maximum generated power when the flue temperature is kept constant at 250 ° C. The wind speed is x (m
/ S), the open circuit voltage (V) is

[0069]

F (x) = 0.1x + 29, and the maximum generated power is

[0070]

## EQU2 ## f (x) = 0.057 × ² + 2.0 × + 78.3.

In general, the incinerator does not significantly change the exhaust temperature even if the incineration amount of the garbage changes, and reduces the wind speed (the exhaust amount).
Designed to change. As shown in FIG. 20, according to the present embodiment, it can be seen that stable power generation characteristics can be obtained without depending much on the wind speed. It shows that it can be obtained.

[0072]

As described above, the mounting structure of the thermoelectric generation module according to the present invention has the structure of the thermoelectric generation module disposed between the high-temperature plate serving as the heat source on the heating side and the low-temperature plate serving as the heat source on the cooling side. In the mounting structure, the high-temperature plate and the low-temperature plate are fixed with a plurality of SUS304 stainless steel M4 screws with the thickness of the fastening portion of the high-temperature plate being 3 to 15 mm, so that the thermoelectric power generation module has a simple structure and is inexpensive. Mounting structure can be realized. If the fixing screw is made of the same material as the material of the high-temperature plate or a material with a very close coefficient of thermal expansion, distortion due to the difference in thermal expansion between the high-temperature plate and the screw can be prevented, and the fastening part of the high-temperature plate can be prevented. The thickness of 3-1
When it is 5 mm, destruction due to distortion can be prevented. When a resin heat conductive sheet or heat conductive grease is interposed between the low-temperature plate and the thermoelectric power generation module, distortion due to thermal expansion can be absorbed, and the difference in thickness between the plurality of thermoelectric power generation modules can be adjusted. When the high-temperature plate and / or the low-temperature plate is made of a metal material whose surface is insulated, the insulating plate between the thermoelectric power generation module and the high-temperature plate and the low-temperature plate can be omitted, and the power generation efficiency can be improved.

[0073]

According to the method of the present invention, the high-temperature plate, the thermoelectric power generation module, and the low-temperature plate are laminated, and the high-temperature plate and the low-temperature plate are fixed with a plurality of screws. If a heat sheet or adhesive is used, the cost of the material will be less than 100 yen and the costs associated with conventional methods will be virtually negligible. In addition, in the method of bonding the thermoelectric power generation module to the high-temperature plate with a hard adhesive, it is not necessary to adjust the thickness of a plurality of modules having different thicknesses by re-polishing, so that the cost for that can be eliminated, and industrially An extremely advantageous power generation system can be provided. The present invention is particularly effective when applied to an incinerator power generation system.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of a first reference example of the present invention.

FIG. 2 is a schematic sectional view of a thermoelectric generation module.

FIG. 3 is a schematic diagram illustrating fixing with screws.

FIG. 4 is a block diagram of a power generation characteristic measurement system.

FIG. 5 is a diagram showing power generation characteristics of a first reference example.

FIG. 6 is a diagram showing power generation characteristics of a conventional example.

FIG. 7 is a diagram showing a comparison between power generation characteristics of a reference example of the present invention and a conventional example.

FIG. 8 is a schematic sectional view of a fourth reference example of the present invention.

FIG. 9 is a schematic sectional view of a fifth reference example of the present invention.

FIG. 10 is a schematic sectional view of the first embodiment of the present invention.

FIG. 11 is a diagram showing power generation characteristics of the first embodiment.

FIG. 12 is a diagram illustrating power generation characteristics of the first example.

FIG. 13 is a diagram showing power generation characteristics and heat cycle characteristics of the first embodiment.

FIG. 14 is a diagram illustrating an incinerator power generation system to which the present invention is applied.

FIG. 15 is a diagram showing power generation characteristics of the incinerator power generation system.

FIG. 16 is a diagram showing power generation characteristics of the power generation characteristics of the incinerator power generation system.

FIG. 17 is a diagram showing power generation characteristics of the power generation characteristics of the incinerator power generation system.

FIG. 18 is a diagram showing power generation characteristics of the power generation characteristics of the incinerator power generation system.

FIG. 19 is a diagram showing flue temperature dependence of power generation characteristics of an incinerator power generation system.

FIG. 20 is a diagram showing wind speed dependence of power generation characteristics of an incinerator power generation system.

FIG. 21 is a schematic sectional view of an example of a conventional thermoelectric generation module.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1, 1a, 1b, 1c Thermoelectric power generation module 2a, 2b, 2c, 2d, 2e, 2f Thermal conductive grease 3a, 3b Electric insulating plate 4 High temperature plate 4a Tightening part of high temperature plate 5 Low temperature plate 6 High temperature heat source 7 Low temperature heat source 8 Hard heat insulating material 9 Porous heat insulating material 10 Frame 11 Holding screw 12 Load cell 13 Flat spring 14 Guide 15 Steel ball 16 Screw 17 Heat conductive silicone sheet 18 Fixing screw 19 Heat insulating material 21 Power generation element assembly 22 Metal electrode 23 Lead wire 24 Protective resin 25 Slip resistor 26 Ammeter 27 Voltmeter 31 Flue 32 Heat collecting fin 33 Heat pipe 33a Heat receiving section of heat pipe 33b Heat radiating section of heat pipe 34 Water cooling holder 35 Power generation unit 36 Thermal insulation

Continuation of the front page (56) References JP-A-60-170279 (JP, A) JP-A-8-64876 (JP, A) JP-A-57-63246 (JP, A) JP-A-56-167377 (JP) JP-A-7-176798 (JP, A) JP-A-50-58464 (JP, A) JP-A-3-41207 (JP, A) JP-A-3-162587 (JP, A) 61-109161 (JP, U) Japanese Utility Model 63-177 (JP, U) Japanese Utility Model 57-2679 (JP, U) Japanese Utility Model 39-14428 (JP, Y1) (58) Fields surveyed (Int. Cl. ^7, DB name) H01L 35/30 H01L 35/32 H02N 11/00

Claims (2)

(57) [Claims] 1. A method of mounting a thermoelectric power generation module disposed between a high-temperature plate serving as a heat source on the heat generation side and a low-temperature plate serving as a heat source on the cooling side, wherein a high-temperature plate having a portion having a thickness of 3 to 15 mm is prepared. The thermoelectric power generation module comprises a plurality of modules having different thicknesses, an adhesive is applied to one surface of the plurality of modules and pressed against the high-temperature plate or the low-temperature plate, and the height of the other surface of the plurality of modules is increased. Bonding the hot plate, stacking the high-temperature plate, the thermoelectric generator module and the low-temperature plate, and directly compressing a portion of the high-temperature plate having a thickness of 3 to 15 mm by a plurality of SUS304 stainless steel M4 screws. And fixing the high-temperature plate and the low-temperature plate with the plurality of SUS304 stainless steel M4 screws. How to install the tool. 2. A method for mounting a thermoelectric power generation module disposed between a high-temperature plate serving as a heat source on the heat generation side and a low-temperature plate serving as a heat source on the cooling side, wherein a high-temperature plate having a portion having a thickness of 3 to 15 mm is prepared. The thermoelectric power generation module comprises a plurality of modules having different thicknesses, an adhesive is applied to the surface of the high-temperature plate or the low-temperature plate, and one surface of the plurality of modules is coated with the adhesive. And bonding the same surface while making the other surfaces of the plurality of modules have the same height, laminating the high-temperature plate, the thermoelectric generation module and the low-temperature plate, and a plurality of SUs.
The portion of the high-temperature plate having the thickness of 3 to 15 mm is directly compressed with an S304 stainless steel M4 screw to connect the high-temperature plate and the low-temperature plate to the plurality of SUS304 stainless steel M4 screws.
A method for mounting a thermoelectric generation module, comprising a step of fixing with a screw.