JP2013243303A - Power generator and power generation method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power generator and a power generation method capable of generating power even if a heat source, e.g., waste-heat, cannot be obtained.SOLUTION: A heat storage tank housing a heat storage material for suppressing internal temperature change is provided. The heat storage surface, i.e., one end face of a thermoelectric conversion module, is thermally coupled with the heat storage material and the heat absorption/radiation surface, i.e., the other end face of the thermoelectric conversion module, is thermally coupled with the outside. When the external temperature goes above the internal temperature of the heat storage tank, the thermoelectric conversion module stores external heat in the heat storage tank via the heat absorption/radiation surface and the heat storage surface and generates power. When the external temperature goes below the internal temperature of the heat storage tank, the thermoelectric conversion module radiates the heat stored in the heat storage tank via the heat storage surface and the heat absorption/radiation surface and generates power.

Description

  The present invention relates to a power generator that supplies electric power to an electronic device or the like, and more particularly, to a power generator using a thermoelectric conversion module that can generate power due to a temperature difference between thermoelectric conversion materials.

  Patent Document 1 discloses a technique relating to a small-capacity power supply device that generates power using unused exhaust heat. According to this method, even when the supply of heat from the heat source is interrupted, the power generation of the small-capacity electric power can be temporarily maintained.

JP 2008-251928 A

  However, the above device cannot generate power if a suitable heat source such as exhaust heat cannot be obtained, and if power is not supplied from the heat source for a long time, power generation cannot be continued thereafter. Can not.

  An object of the present invention is to provide a power generation apparatus and a power generation method capable of generating power even when a heat source such as exhaust heat cannot be obtained.

The power generation device of the present invention is a power generation device using a thermoelectric conversion module capable of generating power due to a temperature difference between thermoelectric conversion materials, and includes a heat storage tank containing a heat storage material that suppresses an internal temperature change. The heat storage surface, which is an end surface, is thermally coupled to the heat storage material, and the heat absorption / radiation surface, which is the other end surface of the thermoelectric conversion module, is thermally coupled to the outside. If the temperature becomes higher, the thermoelectric conversion module generates electric power while storing external heat in the heat storage tank via the heat absorption / radiation surface and the heat storage surface, and when the external temperature becomes lower than the temperature in the heat storage tank, The thermoelectric conversion module generates electricity while radiating the heat stored in the heat storage tank to the outside through the heat storage surface and the heat absorption / radiation surface.
According to this power generation apparatus, power generation is possible without using a heat source such as exhaust heat because power generation is performed using an external temperature change.

  The heat storage material may be configured to have a melting point between the maximum temperature and the minimum temperature of the external temperature.

  The heat storage material may be composed of a plurality of materials having different melting points.

  You may provide the electrical storage means to store the electric power generated by the said thermoelectric conversion module.

  The external temperature may be air temperature, and may utilize a temperature difference between daytime air temperature and night air temperature.

  The external temperature may be an ambient temperature of an arbitrary device, and may utilize a temperature difference between a temperature when the arbitrary device is operating and a temperature when the arbitrary device is stopped.

The power generation method of the present invention is a power generation method using a thermoelectric conversion module capable of generating power due to a temperature difference between thermoelectric conversion materials, using a heat storage tank containing a heat storage material that suppresses an internal temperature change, and The heat storage surface, which is an end surface, is thermally coupled to the heat storage material, and the heat absorption / radiation surface, which is the other end surface of the thermoelectric conversion module, is thermally coupled to the outside. The thermoelectric conversion module generates power while storing external heat in the heat storage tank via the heat absorption / heat dissipation surface and the heat storage surface, and the external temperature becomes lower than the temperature in the heat storage tank. The thermoelectric conversion module has a step of generating electricity while radiating heat stored in the heat storage tank to the outside via the heat storage surface and the heat absorption / heat radiation surface. And butterflies.
According to this power generation method, since power generation is performed using an external temperature change, power generation is possible without the need for a heat source such as exhaust heat.

  According to the power generation device of the present invention, power generation is performed using an external temperature change, so power generation is possible without the need for a heat source such as exhaust heat.

  According to the power generation method of the present invention, power generation is performed using an external temperature change, so power generation is possible without the need for a heat source such as exhaust heat.

It is a figure which shows the electric power generation system provided with the electric power generating apparatus of one Embodiment, (a) is a schematic sectional drawing of a charging system, (b) is a block diagram which shows the structure of a controller. The figure which shows the change of the air temperature between the heat absorption / radiation surface and the heat storage surface during one day.

  Hereinafter, an embodiment of a power generator according to the present invention will be described. The case where the power generation device of the present invention is applied to a power generation device including a thermoelectric conversion module and a heat storage tank, and further to a power generation system including a power storage unit as power storage means will be described as an example.

  FIG. 1 is a diagram illustrating a power generation system including a power generation device according to an embodiment, where (a) is a schematic cross-sectional view of a charging system, and (b) is a block diagram illustrating a configuration of a controller.

  As shown in FIG. 1A, a power generation system 1 includes a power generation device 10 that generates power using a temperature difference, a controller 20 that controls the power generated by the power generation device 10, and a power storage unit that uses a capacitor and the like. 30. The electric power generated by the power generation apparatus 10 is charged in the power storage unit 30 via the controller 20 and supplied to an external device (not shown). The external device is, for example, a temperature sensor or a pressure sensor.

  The power generation device 10 accommodates a thermoelectric conversion module 11 that converts thermal energy into electrical energy using the Seebeck effect, and a heat storage material 12a and a heat storage material 12a that keep the internal temperature substantially constant. A heat storage tank 12 including a heat insulating container 12b. The heat insulating container 12b suppresses the heat entering and leaving between the heat storage material 12a and the outside air.

  As the thermoelectric conversion module 11, an arbitrary configuration can be used. For example, as shown in FIG. 1, a member 11A made of a plurality of n-type thermoelectric conversion materials and a member 11B made of the same number of p-type thermoelectric conversion materials It is possible to configure the thermoelectric conversion module 11 in which the power generation elements composed of the same number of members 11A and 11B are formed. Each pair of members 11A and 11B is joined to each other to form a power generation element that generates a potential difference corresponding to a temperature difference between both ends thereof. By connecting these power generation elements in series, a voltage in which the potential differences of the individual power generation elements are added can be obtained. The electric power generated by the thermoelectric conversion module 11 is drawn out by the lead wire 14 and connected to the heat storage unit 30 via the controller 20, thereby configuring the power generation system 1. In addition, since the structure of the thermoelectric conversion module is known, the detailed description is abbreviate | omitted.

  As the heat storage material 12a of the heat storage tank 12, materials such as paraffin, silicon gel, water, various organic compounds, or a mixture thereof can be used. For example, when using the temperature difference between daytime and nighttime, power generation efficiency is selected by selecting a heat storage material 12a that has a high ability to maintain the temperature in the heat storage tank 12 between the midday air temperature and the night air temperature. Can be improved.

  A contact member 15 made of a material having high thermal conductivity is bonded to the heat storage surface 11C of the thermoelectric conversion module 11 corresponding to the lower surface in FIG. 1A, and the surface 15a (the lower surface in FIG. 1A) is the heat storage surface. It is in contact with the material 12a. By this contact member 15, efficient transfer of heat from the heat storage material 12 a to the thermoelectric conversion module 11 or from the thermoelectric conversion module 11 to the heat storage material 12 a is achieved.

  In FIG. 1A, the heat absorption / radiation surface 11D of the thermoelectric conversion module 11 corresponding to the upper surface is exposed to the outside air. In addition, in order to reduce the thermal resistance between the outside air and the thermoelectric conversion module 11, a heat radiator may be attached to the heat absorption / heat radiation surface 11D.

  As shown in FIG. 1B, the controller 20 includes a detection circuit 21 that detects the polarity of power generation of the thermoelectric conversion module 11, a charging circuit 22 that outputs a charging current for charging the power storage unit 30, and a detection circuit. The switch SW1 and the switch SW2 controlled according to the detection result 21 are provided. The switches SW1 and SW2 are switched in conjunction with either the P side or the Q side based on the signal from the detection circuit 21. Thereby, the polarity of the voltage from the thermoelectric conversion module 11 given to the charging circuit 22 is controlled so as not to be reversed regardless of the polarity of the power generation of the thermoelectric conversion module 11.

  Next, operation | movement of the electric power generating apparatus 1 of this embodiment is demonstrated.

  FIG. 2 is a diagram illustrating a change in the air temperature during one day between the heat absorption / heat radiation surface 11D and the heat storage surface 11C. In FIG. 2, a heat sink / heat radiating surface 11D is provided with a radiator so that the temperature of the heat absorbing / heat radiating surface 11D is linked to the outside air temperature, and the latent heat type heat storage having a melting point between the lowest temperature and the highest temperature of the outside air as the heat storage material 12a The example of the temperature change at the time of using a material is shown. In FIG. 2, the daily cycles (A) to (F) will be described as an example. In FIG. 2, the temperature of the heat absorption / radiation surface 11D is indicated by a solid line, and the temperature of the heat storage surface 11C is indicated by a broken line.

  In the example of FIG. 2, at time 0:00 (A), the heat storage material 12 a in the heat storage tank 12 is in a molten state with the heat stored during the day before. When the outside air temperature decreases at night, the temperature of the heat absorption / radiation surface 11D also decreases. On the other hand, the temperature of the heat storage surface 11C becomes substantially constant because the heat storage material 12a starts to solidify near the melting point of the heat storage material 12a and latent heat is released. For this reason, the temperature difference between the heat storage surface 11C and the heat absorption / radiation surface 11D is maintained, and the thermoelectric conversion module 11 generates a potential difference corresponding to the temperature difference.

  When the thermoelectric conversion module 11 performs power generation based on a temperature difference, the heat moves from the heat storage surface 11C to the heat absorption / radiation surface 11D, and the heat storage material 12a solidifies, that is, releases latent heat (B). Thus, when the external temperature becomes lower than the temperature in the heat storage tank 12, the thermoelectric conversion module 11 generates power while radiating the heat stored in the heat storage tank 12.

  When all of the heat storage material 12a is solidified, the temperature of the heat storage surface 11C becomes substantially equal to the heat absorption / radiation surface 11D. Therefore, power generation stops (C).

  When the sun rises and the outside air temperature rises, the temperature of the heat absorption / heat radiation surface 11D also rises. The heat storage material 12a starts to melt near the melting point of the heat storage material 12a, and latent heat is absorbed. Therefore, the temperature of the heat storage surface 11C becomes substantially constant, a temperature difference from the heat absorption / radiation surface 11D occurs, and the thermoelectric conversion module 11 can generate power again (D).

  When power is generated by the thermoelectric conversion module 11, heat is transferred from the heat absorption / radiation surface 11D to the heat storage surface 11C, and the heat storage material 12a is melted, that is, latent heat is accumulated (E). As described above, the thermoelectric conversion module 11 generates power while storing heat in the heat storage tank 12 when the external temperature becomes higher than the temperature in the heat storage tank 12.

  When all of the heat storage material 12a is melted, the temperature of the heat storage surface 11C becomes substantially equal to the heat absorption / radiation surface 11D. The temperature difference disappears and power generation in the thermoelectric conversion module 11 stops (F).

  By repeating the cycle of (A) to (F) in FIG. 2 every day, the thermoelectric conversion module 11 generates power during (B) and (E). The generated power is converted in polarity and voltage by the controller 20, and the power storage unit 30 is charged.

  As described above, the power generation apparatus 10 of the present embodiment includes the thermoelectric conversion module 11 that can generate power due to a temperature difference, and the heat storage tank 12 that stores a heat storage material that suppresses a change in internal temperature, and has an external temperature. When it becomes higher than the temperature in the heat storage tank 12, the thermoelectric conversion module 11 generates power while storing heat in the heat storage tank 12 ((E) of FIG. 2), and when the external temperature becomes lower than the temperature in the heat storage tank 12, The thermoelectric conversion module 11 is configured to generate electricity while dissipating the heat stored in the livestock heat tank 12 ((B) in FIG. 2). As a result, power generation is possible without using a heat source such as exhaust heat because power is generated using an external temperature difference such as the temperature of day and night that exists in a wide range such as outdoors or indoors that are not air-conditioned.

  In addition, since the power generation apparatus 10 of the present embodiment is used after the generated power is temporarily stored in the power storage unit 30, the power charged in the power storage unit 30 can be used even while power generation cannot be performed. Furthermore, if the power storage capacity of the power storage unit 30 is sufficiently large, for example, power can be supplied from the power storage unit 30 even on a day when the temperature difference between day and night is small due to the influence of the weather, etc. The device (not shown) can be continuously operated.

  Note that a mixture of a plurality of materials having different melting points may be used as the heat storage material 12a. By using a plurality of materials having different melting points, it is possible to always use latent heat even when there is a difference between the maximum temperature (maximum temperature) and the minimum temperature (minimum temperature) depending on the season, and stable power generation performance can be obtained.

  Moreover, in the electric power generating apparatus 10 of this embodiment, although the heat storage material 12a which can utilize latent heat is used, you may use the heat storage material which utilizes only sensible heat. In addition, instead of configuring the heat absorption / radiation surface 15 to be as close as possible to the outside air temperature, use a heat absorption / heat radiation panel that is exposed to sunlight during the day and becomes hot and cool at night due to radiation cooling. The temperature difference may be larger than the outside air temperature.

  Furthermore, in the power generation system 1 of the present embodiment, the power stored in the power generation device 10 is stored in a capacitor as a power storage means. However, even if the power stored in the power generation device 10 is stored in a secondary battery such as a lithium ion battery. Good.

  Furthermore, although the power generation apparatus 10 of the present embodiment uses the temperature difference between the outside air temperatures that naturally occur between day and night, the power generation may be performed using a temperature difference that occurs artificially. For example, you may generate electric power using the temperature difference (temperature difference with the ambient temperature of an apparatus, and a thermal storage material) at the time of operation | movement of an arbitrary apparatus, and a stop. As an apparatus, for example, an apparatus that operates only for a certain time during a day can be used.

  The scope of application of the present invention is not limited to the above embodiment. The present invention can be applied to a power generation apparatus having a thermoelectric conversion module capable of generating power due to a temperature difference between thermoelectric conversion materials and a heat storage tank capable of storing heat of the heat absorption / radiation surface.

1 Power generation system (power generation equipment)
10 Power generator (power generator)
DESCRIPTION OF SYMBOLS 11 Thermoelectric conversion module 12 Thermal storage tank 12a Thermal storage material 30 Electrical storage part (electric storage means)

Claims (7)

In the power generation device using the thermoelectric conversion module that can generate power due to the temperature difference of the thermoelectric conversion material,
It has a heat storage tank that contains a heat storage material that suppresses internal temperature changes,
While thermally connecting the heat storage surface which is one end surface of the thermoelectric conversion module to the heat storage material,
The heat absorption / radiation surface which is the other end surface of the thermoelectric conversion module is thermally coupled to the outside,
When the external temperature becomes higher than the temperature in the heat storage tank, the thermoelectric conversion module generates electric power while storing external heat in the heat storage tank via the heat absorption / heat radiation surface and the heat storage surface,
When the external temperature becomes lower than the temperature in the heat storage tank, the thermoelectric conversion module generates electricity while radiating the heat stored in the heat storage tank to the outside via the heat storage surface and the heat absorption / radiation surface. A power generator.   The power generation device according to claim 1, wherein the heat storage material has a melting point between the highest temperature and the lowest temperature of the external temperature.   The power generation device according to claim 1, wherein the heat storage material includes a plurality of materials having different melting points.   The power generator according to claim 1, further comprising a power storage unit that stores electric power generated by the thermoelectric conversion module.   The power generation apparatus according to any one of claims 1 to 4, wherein the external temperature is an air temperature, and uses a temperature difference between a daytime air temperature and a night air temperature.   The external temperature is an ambient temperature of an arbitrary device, and uses a temperature difference between a temperature during operation of the arbitrary device and a temperature during shutdown. The electric power generating apparatus as described in any one. In the power generation method using the thermoelectric conversion module capable of generating power due to the temperature difference of the thermoelectric conversion material,
Using a heat storage tank that contains a heat storage material that suppresses internal temperature changes,
While thermally connecting the heat storage surface which is one end surface of the thermoelectric conversion module to the heat storage material,
The heat absorption / radiation surface which is the other end surface of the thermoelectric conversion module is thermally coupled to the outside,
When the external temperature becomes higher than the temperature in the heat storage tank, the thermoelectric conversion module generates electricity while storing external heat in the heat storage tank via the heat absorption / heat radiation surface and the heat storage surface;
When the external temperature becomes lower than the temperature in the heat storage tank, the thermoelectric conversion module generates electricity while radiating the heat stored in the heat storage tank to the outside via the heat storage surface and the heat absorption / heat radiation surface;
A power generation method comprising:

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