JP2000353830A - Method and device for driving peltier element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To drive a Peltier element, using a power source of a current capacity sufficient for constant current. SOLUTION: A DC current is supplied to a Peltier element 2 via a step-down chopper type power source 1, to which a rectified DC voltage is inputted. Cooling side and heat radiating side temperatures Tc and Th respectively of the Peltier element 2 are detected with a first temperature sensor 8, and the detected cooling side temperature Tc and heat radiating side temperature Th are supplied to a power-source control part 6 to generate a gate control signal. The gate control signal passes through a gate drive circuit 7 and is then supplied to a switching element of the step-down chopper type power source 1 as a control signal, to suppress a supply current at start-up.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for driving a Peltier element, and more particularly, to a method and an apparatus for driving a Peltier element by supplying a direct current to a Peltier element by a power supply device. .

[0002]

2. Description of the Related Art Conventionally, a Peltier element capable of transferring heat from a heat-absorbing side to a heat-dissipating side by supplying a DC current has been known. Focusing on advantages such as high mechanical strength, low vibration without moving parts, and precise temperature control, it has been applied to various applications. .

FIG. 11 is a block diagram showing a conventional Peltier device driving device.

In this Peltier device driving device, a DC current is supplied to a Peltier device 92 through a step-down chopper type power supply 91 to which a rectified DC voltage is input. Then, a resistance voltage dividing circuit 93 is connected between the input terminals of the Peltier element 92 to detect an output voltage (output voltage of the step-down chopper type power supply 91) and to detect the output voltage.
A resistor 94 for detecting an overcurrent is connected to one of the input terminals 2 and the voltage between the terminals of the resistor 94 is supplied to an overcurrent detecting unit 95 to detect the overcurrent. Further, the detected output voltage and the overcurrent detection signal from the overcurrent detection unit 95 are supplied to a power supply control unit 96 to generate a gate control signal, and this gate control signal is passed through a gate drive circuit 97 to a step-down chopper type power supply. The control signal is supplied to the switching element 91 as a control signal.

The step-down chopper type power supply 91
Is a switching element 91a connected in series with one output terminal of the DC voltage source, a reactor 91b connected in series with the switching element 91a, and a reactor 91b.
b, a diode 91c connected between the input terminal of the DC voltage source and the other output terminal of the DC voltage source, and a capacitor 91d connected between the output terminal of the reactor 91b and the other output terminal of the DC voltage source. have.

The power control section 96 calculates a difference between a predetermined set voltage and the detected output voltage, compares the calculated difference with a predetermined triangular wave reference signal, and outputs a pulse corresponding to the difference. A gate control signal having a width is generated. The gate control signal is amplified by the gate drive circuit 97 and supplied to the switching element 91a.
Then, in response to the input of the overcurrent detection signal, the generation of the gate control signal is prohibited, and the Peltier element 92 is protected.

The overcurrent detecting section 95 compares the voltage between terminals of the resistor 94 for detecting overcurrent with a limit terminal voltage corresponding to a preset limit current, and when the terminal voltage becomes higher than the limit terminal voltage. In response to this, an overcurrent detection signal is output.

Therefore, in consideration of the fact that the Peltier element 92 has a substantially constant resistance value, a voltage value that can realize a desired supply current is set as the set voltage, so that the Peltier element 92 To supply the desired current and transfer heat from the heat-absorbing side to the heat-radiating side,
Eventually, the object can be cooled or heated.

[0009]

The Peltier element 92 is assumed to have a substantially constant electrical resistance. However, in practice, when the temperature difference between the heat absorbing side and the heat radiating side is small, the resistance is small. On the other hand, when the temperature difference is large, the resistance value becomes large and it becomes difficult for current to flow. In addition, even when the temperature on the heat radiation side of the Peltier element 92 increases, the current does not easily flow.

Actually, when a constant voltage is applied to the Peltier element, the temperature Tc on the heat absorption side and the temperature Th on the heat radiation side of the Peltier element change over time as shown in FIG. In FIG. 12, (A) is the heat radiation side temperature Th of the Peltier element, (B) is the heat absorption side temperature Tc of the Peltier element,
(C) is the ambient temperature (room temperature) Ta of the Peltier element, (D)
Is a supply current to the Peltier element. Note that FIG. 12 shows only an example, and the actual temperature, temperature difference, and the like differ depending on conditions. Then, the DC voltage applied to the Peltier element 92 is set to 10 V, and the current flowing through the Peltier element is obtained at this time. According to the characteristic table, at startup, Th = 25 ° C., and the temperature difference ΔT = Th−Tc = Since the temperature is 0 ° C., a current of 5.8 A flows.
3. 0 ° C. and temperature difference ΔT = Th−Tc = 40 ° C.
A current of 5 A flows (see (D) in FIG. 12). That is, at the time of startup, a current that is 20 to 30% higher than that in the steady state flows.

Therefore, if a power supply with a rating of 5 A is adopted with a margin of about 10% with respect to the steady-state current, the rating will be exceeded at the time of startup. For this reason, it is necessary to employ a power supply capable of supplying a current higher than the rated current for a certain period of time at startup or a power supply having a large current capacity so as to cover the current at startup. As a result, power supply costs increase,
This leads to an increase in size.

This inconvenience occurs not only when a purchased product is used as a power source but also when a dedicated power source is developed.

[0013]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and a Peltier element driving method and a Peltier element driving method capable of driving a Peltier element using a power supply having a necessary and sufficient current capacity with respect to a steady current. It is intended to provide a device.

[0014]

According to a first aspect of the present invention, there is provided a method for driving a Peltier device. In driving the Peltier device by supplying a direct current to the Peltier device by a power supply device, the temperature of the heat absorption side and the radiation side of the Peltier device are reduced. This is a method of detecting the temperature and controlling the power supply device to control the current supplied to the Peltier element based on the difference between the heat radiation side temperature and the heat absorption side temperature.

According to a second aspect of the present invention, there is provided a method of driving a Peltier element by detecting an ambient temperature and controlling a supply current to the Peltier element in consideration of the ambient temperature.

The method of driving a Peltier element according to a third aspect is a method of detecting a temperature of a control target by the Peltier element and controlling a supply current to the Peltier element in consideration of the temperature of the control target.

According to a fourth aspect of the present invention, there is provided a Peltier device driving device for driving a Peltier device by supplying a direct current to the Peltier device by a power supply device. The power supply device includes a first temperature detecting means for detecting, and a first power supply control means for controlling a power supply device to control a supply current to the Peltier element based on a difference between the heat radiation side temperature and the heat absorption side temperature.

According to a fifth aspect of the present invention, the Peltier device driving device further includes a second temperature detecting means for detecting an ambient temperature, and the first power supply control means controls a supply current to the Peltier element in consideration of the ambient temperature. In order to control the power supply device.

According to a sixth aspect of the present invention, there is provided a Peltier device driving device comprising: a third temperature detecting means for detecting a temperature of a control target by the Peltier device; and a power supply device for controlling a current supplied to the Peltier device based on the temperature of the control target. And a second power supply control means for controlling.

[0020]

According to the Peltier device driving method of the present invention, when the Peltier device is driven by supplying a direct current to the Peltier device by a power supply device, the temperature on the heat absorption side and the temperature on the heat radiation side of the Peltier device are detected. Since the power supply is controlled to control the current supplied to the Peltier element based on the difference between the heat radiation side temperature and the heat absorption side temperature,
By detecting the difference between the heat radiation side temperature and the heat absorption side temperature, it is possible to determine whether it is immediately after startup or in a steady state,
By controlling the current supplied to the Peltier element in response to the determination result, it is possible to prevent the disadvantage that a current larger than the current capacity of the power supply is supplied to the Peltier element at startup. As a result, the current capacity of the power supply can be set to a necessary and sufficient current capacity with respect to the supply current in a steady state.
Enlargement can be prevented.

In the Peltier device driving method according to the second aspect, the ambient temperature is also detected, and the supply current to the Peltier device is controlled in consideration of the ambient temperature. On the other hand, the Peltier element can be operated so as to make a predetermined temperature difference, and the supply current can be finely controlled.

According to the Peltier device driving method of the third aspect, the temperature of the control target by the Peltier device is also detected, and the current supplied to the Peltier device is controlled in consideration of the temperature of the control target. In addition to the effect of the first or second aspect, by controlling the supply current according to the temperature of the control target, it is possible to suppress the current from flowing too much and to increase the efficiency of the Peltier element.

Further description will be given.

The control of the temperature of the control object is realized by inputting an error between the set temperature and the detected temperature to a control system (for example, a PID control system). In addition, the characteristics of the Peltier element change with the temperature on the heat absorption side, the temperature on the heat radiation side, the ambient temperature, and so on.
At the time of startup, a large amount of current flows, and the efficiency of the Peltier device deteriorates. However, by adopting the third aspect, it is possible to suppress the current from flowing too much and to increase the efficiency of the Peltier element.

According to the fourth aspect of the present invention, when the Peltier element is driven by supplying a direct current to the Peltier element by a power supply device, the temperature on the heat absorption side and the temperature on the heat radiation side of the Peltier element are determined. (1) The power supply device can be controlled by the first power supply control means so as to control the current supplied to the Peltier element based on the difference between the heat radiation side temperature and the heat absorption side temperature, detected by the temperature detection means.

Therefore, by detecting the difference between the temperature on the heat radiation side and the temperature on the heat absorption side, it is possible to determine whether it is immediately after startup or in a steady state, and control the current supplied to the Peltier element in response to this determination result. By doing so, it is possible to prevent the disadvantage that a current larger than the current capacity of the power supply is supplied to the Peltier element at the time of startup. As a result, the current capacity of the power supply can be set to a necessary and sufficient current capacity with respect to the supply current in a steady state, and the cost and size of the power supply can be prevented from increasing.

According to the Peltier element driving device of the fifth aspect, the ambient temperature can be detected by the second temperature detecting means, and the supply current to the Peltier element can be detected by the first power supply control means in consideration of the ambient temperature. Can be controlled to control the power supply. Therefore, the Peltier element can be operated so that the heat absorption side temperature is set to a predetermined temperature difference with respect to the ambient temperature, and the supply current can be finely controlled.

According to the Peltier device driving device of the present invention, the temperature of the control target by the Peltier device is detected by the third temperature detecting means, and the second power supply control means supplies the Peltier device based on the temperature of the control target. The power supply can be controlled to control the current. Therefore, in addition to the effect of claim 4 or claim 5, by controlling the supply current according to the temperature of the control target, it is possible to suppress the current from flowing too much and to increase the efficiency of the Peltier element.

[0029]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a Peltier device driving method according to an embodiment of the present invention;

FIG. 1 is a block diagram showing an embodiment of a Peltier device driving device according to the present invention.

In this Peltier device driving device, a DC current is supplied to the Peltier device 2 via a step-down chopper type power supply device 1 which receives a rectified DC voltage as an input. Then, a resistor voltage dividing circuit 3 is connected between the input terminals of the Peltier element 2 to detect an output voltage (output voltage of the step-down chopper type power supply 1), and one of the input terminals of the Peltier element 2 is used for detecting an overcurrent. And the voltage between the terminals of the resistor 4 is supplied to the overcurrent detection unit 5 to detect the overcurrent. Further, the temperatures Tc and Th on the heat absorption side (cooling side) and the heat radiation side of the Peltier element 2 are respectively detected by a first temperature sensor (thermistor or the like) 8. Further, the detected output voltage, cooling side temperature Tc, heat radiation side temperature Th,
Is supplied to the power supply controller 6 to generate a gate control signal, and the gate control signal is supplied to the switching element of the step-down chopper type power supply 1 through the gate drive circuit 7 as a control signal.

The step-down chopper type power supply device 1 comprises:
A switching element 1a connected in series with one output terminal of the DC voltage source, a reactor 1b connected in series with the switching element 1a, and an input terminal of the reactor 1b and the other output terminal of the DC voltage source; And a capacitor 1 connected between the output terminal of the reactor 1b and the other output terminal of the DC voltage source.
d. Therefore, the output voltage can be reduced by reducing the pulse width of the gate control signal, and the output voltage can be increased by increasing the pulse width.

The power control unit 6 calculates a difference between a predetermined set voltage and a detected output voltage, compares the calculated difference with a predetermined triangular wave reference signal, and outputs a pulse corresponding to the difference. A gate control signal having a width is generated. The gate control signal is amplified by the gate drive circuit 7 and supplied to the switching element 1a. Then, the power supply controller 6 calculates a difference ΔT between the heat radiation side temperature Th and the cooling side temperature Tc, and changes the level of the triangular wave reference signal based on the calculated difference ΔT. Specifically, the level of the triangular wave reference signal is set such that the pulse width of the gate control signal is reduced in response to the small difference ΔT and the pulse width of the gate control signal is increased in response to the large difference ΔT. To change. Further, the generation of the gate control signal is prohibited in response to the input of the overcurrent detection signal, and the Peltier element 2 is protected.

The overcurrent detection section 5 compares the voltage between terminals of the resistor 4 for detecting overcurrent with a limit terminal voltage corresponding to a preset limit current, and the terminal voltage becomes higher than the limit terminal voltage. In response to this, an overcurrent detection signal is output.

FIG. 2 is a side view showing an example of use of the Peltier device 2.

The Peltier element 2 is formed by connecting a large number of thermoelectric conversion chips 2a in series via an electrode plate (electrode plate formed by dividing the adjacent thermoelectric conversion chips 2a into a large number in order to connect them in series) 2b. The cooling side and the heat radiation side of all the thermoelectric conversion chips 2a are arranged on the same side.
In order to improve the operability of the Peltier element, all the cooling-side electrode plates are connected to the ceramic plate 2e, and all the radiation-side electrode plates are connected to the ceramic plate 2f. Further, heat sinks 2c and 2d are provided on the cooling side and the heat radiation side, respectively. Therefore, for example, the first temperature sensor 8
Is provided, the temperature on the cooling side and the temperature on the heat radiation side can be detected. The heat sinks 2c and 2d may exchange heat with air or may exchange heat with a liquid such as water.

The operation of the Peltier device driving device having the above configuration is as follows.

As shown in FIG. 3, the heat radiation side temperature Th, the cooling side temperature Tc, and the room temperature of the Peltier element 2 change as the operation time of the Peltier element 2 elapses. The Peltier device 2 in the case where the heat radiation side temperature Th is 25 ° C.
The relationship between the applied voltage Vin and the supply current I is as shown in FIG. The relationship between the applied voltage Vin of the Peltier element 2 and the supply current I when the heat radiation side temperature Th is 50 ° C. is as shown in FIG. 4 and 5, (A), (B), (C), and (D) show that the difference ΔT between the heat radiation side temperature Th and the cooling side temperature Tc is 0 ° C., 20 ° C.
The relationship in the case of ° C, 40 ° C, and 60 ° C is shown, respectively.

Therefore, at the time of startup, the supply current I determined based on the characteristic shown in FIG. 4A is supplied, and during the steady state, the supply current I determined based on the characteristic shown in FIG. 5C is supplied. You. Here, when the DC voltage applied to the Peltier element 2 is set to 10 V, a supply current of about 5.8 A is supplied to the Peltier element 2 at startup, while a supply current of about 4.5 A is supplied in a steady state. Peltier device 2
Supplied to

However, when this embodiment is adopted, the power supply control unit 6 calculates the difference ΔT between the heat radiation side temperature Th and the cooling side temperature Tc, and based on the calculated difference ΔT, generates the triangular wave reference signal. Since the pulse width of the gate control signal is controlled by changing the level, the DC voltage applied to the Peltier element 2 at startup can be reduced. Specifically, if the pulse width of the gate control signal is set so that the DC voltage applied to the Peltier element 2 at the time of startup is about 7 V, the supply current to the Peltier element 2 at the time of startup is about 4.5 A ( (Supply current approximately equal to the supply current at a constant time).

As a result, the current capacity of the power supply can be set to a necessary and sufficient current capacity with respect to the supply current in a steady state.
Compared to a case where a power supply capable of supplying a supply current at the time of startup to the Peltier element 2 is employed, cost reduction and downsizing of the power supply can be achieved.

FIG. 6 is a flowchart for explaining one embodiment of the Peltier element driving method of the present invention.

In step SP1, the heat radiation side temperature Th and the cooling side temperature Tc of the Peltier element are detected, and step S1 is performed.
In P2, the difference ΔT between the two temperatures is calculated, and the
In 3, the supply current is controlled by controlling the voltage applied to the Peltier element based on the calculated difference ΔT. Specifically, when the difference ΔT is small, the applied voltage is reduced, and when the difference ΔT is large, the applied voltage is increased.

When this method is adopted, the same operation as the embodiment of FIG. 1 can be achieved.

FIG. 7 is a block diagram showing another embodiment of the Peltier device driving device according to the present invention.

This Peltier device driving device is provided with a predetermined first
A gain control unit 11 that receives a voltage command and a second voltage command that is determined based on the first voltage command and the gain of the gain control unit 11 are input, and a DC voltage corresponding to the second voltage command is output. It has a variable output DC power supply 12 applied to the element 2, and a temperature difference calculator 13 that calculates a difference ΔT between the heat radiation side temperature Th and the cooling side temperature Tc and supplies the difference ΔT to the gain controller 11. Further, a second temperature sensor 14 for detecting the ambient temperature of the Peltier element 2 is provided, and the detected ambient temperature Ta is also supplied to the temperature difference calculating unit 13.

The gain control section 11 determines the heat radiation side temperature Th.
When the difference ΔT between the temperature and the cooling side temperature Tc is less than 20 ° C., the gain is set to 0.8, and when the difference ΔT is 20 ° C. or more, the gain is set to 1.0.

The temperature difference calculator 13 calculates the heat radiation side temperature Th.
Not only the difference ΔT between the cooling side temperature Tc and the ambient temperature Ta is calculated, but also the difference between the cooling side temperature Tc and the ambient temperature Ta is calculated. The variable output DC power supply 12 is controlled so as to be equal to the temperature difference.

The operation of the Peltier device driving device of this embodiment is as follows.

While the first voltage command having a constant value is supplied to the gain control unit 11, as shown in FIG. 3, a period until the difference ΔT that increases with the lapse of time after the start reaches 20 ° C. Sets the gain to 0.8, outputs a second voltage command having a value of 80% of the first voltage command, and supplies it to the variable output DC power supply 12. Therefore, the supply current to the Peltier element 2 can be reduced to about 80% of the current value determined by the first voltage command.

After the difference ΔT reaches 20 ° C., the gain is set to 1.0, a second voltage command having a value equal to the first voltage command is output, and supplied to the variable output DC power supply 12. . Therefore, the supply current to the Peltier element 2 can be set to about 100% of the current value determined by the first voltage command.

Therefore, even when this embodiment is adopted, the current capacity of the power supply can be made a necessary and sufficient current capacity with respect to the supply current at the time of steady state, and the supply current at the time of startup is supplied to the Peltier element 2. Compared to the case where a power supply that can be supplied is employed, cost reduction and downsizing of the power supply can be achieved.

FIG. 8 is a flow chart for explaining another embodiment of the Peltier element driving method according to the present invention.

In step SP1, the radiation side temperature Th of the Peltier element, the cooling side temperature Tc, and the ambient temperature Ta of the Peltier element are detected. In step SP2, the difference ΔT between the radiation side temperature Th and the cooling side temperature Tc is calculated. Step S
In P3, the supply current is controlled by controlling the voltage applied to the Peltier element based on the calculated difference ΔT and the ambient temperature Ta. Specifically, when the ambient temperature Ta is low, the applied voltage is reduced when the difference ΔT is less than 20 ° C., and when the ambient temperature Ta is high, the applied voltage is increased when the difference ΔT is 20 ° C. or more. .

When this method is adopted, the same operation as the embodiment of FIG. 7 can be achieved.

FIG. 9 is a block diagram showing still another embodiment of the Peltier device driving device according to the present invention.

This Peltier device driving device comprises a third temperature sensor 21 for detecting the temperature of a control object whose temperature is controlled by the Peltier device 2, a predetermined set temperature signal given from the outside, and a temperature of the control object. A temperature difference calculating unit 22 that calculates a difference between the two, a temperature adjustment system 23 that receives the calculated temperature difference as an input, and outputs a first voltage command corresponding to the temperature difference,
A gain control unit that receives a first voltage command and a second voltage command that is determined based on the first voltage command and a gain of the gain control unit, and outputs a DC voltage corresponding to the second voltage command. , A variable output DC power supply 25 applied to the Peltier element 2, a radiation side temperature Th and a cooling side temperature Tc.
And a temperature difference calculator 26 for calculating the difference ΔT from the calculated value and supplying the calculated difference ΔT to the gain controller 24. Further, a second temperature sensor 27 for detecting the ambient temperature of the Peltier element 2 is provided, and the detected ambient temperature is also supplied to the temperature difference calculating unit 26.

The gain control unit 24 determines the heat radiation side temperature Th.
When the difference ΔT between the temperature and the cooling side temperature Tc is less than 20 ° C., the gain is set to 0.8, and when the difference ΔT is 20 ° C. or more, the gain is set to 1.0.

The operation of the Peltier device driving device of this embodiment is as follows.

First, a first voltage command is calculated based on the difference between the set temperature and the temperature of the object to be controlled. However, the maximum value of the first voltage command is predetermined based on the current supplied to the Peltier element 2 in the steady state.

Then, the first voltage command is transmitted to the gain controller 11
During the period until the difference ΔT that increases with the lapse of time from the start reaches 20 ° C. as shown in FIG. 3, the gain is set to 0.8 and the first voltage command is supplied. 8
A second voltage command having a value of 0% is output and supplied to the variable output DC power supply 12. Accordingly, the supply current to the Peltier element 2 is reduced to about 80 of the current value determined by the first voltage command.
%.

After the difference ΔT reaches 20 ° C., the gain is set to 1.0, a second voltage command having a value equal to the first voltage command is output, and supplied to the variable output DC power supply 12. . Therefore, the supply current to the Peltier element 2 can be set to about 100% of the current value determined by the first voltage command.

Therefore, even when this embodiment is adopted, the current capacity of the power supply can be made a necessary and sufficient current capacity with respect to the steady-state supply current. Compared to the case where a power supply that can be supplied is employed, cost reduction and downsizing of the power supply can be achieved. Further, since the first voltage command is calculated based on the difference between the set temperature and the temperature of the control target, optimal driving of the Peltier element 2 can be achieved in accordance with the temperature of the control target.

FIG. 10 is a flowchart for explaining still another embodiment of the Peltier element driving method according to the present invention.

In step SP1, the radiation side temperature Th of the Peltier element, the cooling side temperature Tc, the ambient temperature Ta of the Peltier element, and the temperature of the controlled object whose temperature is controlled by the Peltier element are detected. The difference ΔT between the temperature Th and the cooling side temperature Tc is calculated, and in step SP3, the supply current is controlled by controlling the voltage applied to the Peltier element based on the calculated difference ΔT, the ambient temperature Ta, and the temperature of the control target. Control. Specifically, when the difference between the temperature of the control object and the set temperature is small,
When the ambient temperature Ta is low, when the difference ΔT is less than 20 ° C., the applied voltage is reduced. When the difference between the temperature of the control target and the set temperature is large, when the ambient temperature Ta is high, the difference ΔT is 20 ° C. In the above case, the applied voltage is increased.

When this method is adopted, the same operation as the embodiment of FIG. 9 can be achieved.

In the embodiments shown in FIGS. 7 to 10, the gain is changed in two steps by the gain control section. However, the gain can be changed in three or more steps. It is also possible to change it steplessly.

[0068]

According to the first aspect of the present invention, the current capacity of the power supply is
It is possible to obtain a necessary and sufficient current capacity with respect to a supply current in a steady state, and to achieve a unique effect that a cost increase and an increase in size of a power supply can be prevented.

According to a second aspect of the present invention, in addition to the effect of the first aspect, the Peltier element can be operated so as to make the heat absorption side temperature a predetermined temperature difference with respect to the ambient temperature, and the supply current is finely controlled. It has a specific effect that it can be performed.

According to a third aspect of the present invention, in addition to the effect of the first or second aspect, by controlling the supply current in accordance with the temperature of the control object, it is possible to suppress the excessive flow of the current and to improve the efficiency of the Peltier device. It has a specific effect that it can be performed.

According to the fourth aspect of the present invention, the current capacity of the power supply can be set to a necessary and sufficient current capacity with respect to the supply current in a steady state, and the cost and size of the power supply can be prevented from increasing. Has a unique effect.

According to a fifth aspect of the present invention, in addition to the effect of the fourth aspect, the Peltier element can be operated so as to make the heat absorption side temperature a predetermined temperature difference with respect to the ambient temperature, and the supply current is finely controlled. It has a specific effect that it can be performed.

According to a sixth aspect of the present invention, in addition to the effect of the fourth or fifth aspect, by controlling the supply current according to the temperature of the control target, it is possible to suppress the excessive flow of the current and to improve the efficiency of the Peltier device. It has a specific effect that it can be performed.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of a Peltier device driving device of the present invention.

FIG. 2 is a side view showing an example of use of a Peltier element.

FIG. 3 is a diagram showing a heat radiation side temperature Th, a cooling side temperature Tc, and a room temperature of the Peltier element, which change as the operation time of the Peltier element elapses.

FIG. 4 is a diagram showing an applied voltage-supply current characteristic when the heat radiation side temperature Th of the Peltier element is 25 ° C.

FIG. 5 is a diagram showing an applied voltage-supply current characteristic when the heat radiation side temperature Th of the Peltier element is 50 ° C.

FIG. 6 is a flowchart illustrating one embodiment of a Peltier device driving method according to the present invention.

FIG. 7 is a block diagram showing another embodiment of the Peltier device driving device of the present invention.

FIG. 8 is a flowchart illustrating another embodiment of the Peltier device driving method according to the present invention.

FIG. 9 is a block diagram showing still another embodiment of the Peltier device driving device of the present invention.

FIG. 10 is a flowchart illustrating still another embodiment of the Peltier device driving method according to the present invention.

FIG. 11 is a block diagram showing a conventional Peltier device driving device.

FIG. 12 is a diagram illustrating a change in the operating time of a Peltier device, and a heat-dissipation-side temperature Th and a cooling-side temperature Tc of the Peltier device.
FIG. 3 is a diagram showing room temperature, and a supply current to a Peltier element.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Step-down chopper type power supply device 2 Peltier element 6 Power supply control unit 8 First temperature sensor 11, 24 Gain control unit 12, 25 Variable output DC power supply 13, 26 Temperature difference detection unit 14, 27 Second temperature sensor 21 Third temperature sensor 22 Temperature difference calculator 23 Temperature adjustment system

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5H730 AA15 BB13 BB57 EE08 EE10 FD01 FD31 FD61 FF02 FG05 XX03 XX15 XX23 XX35

Claims (6)

[Claims] 1. A method for driving a Peltier element (2) by supplying a direct current to the Peltier element (2) by a power supply device (1), wherein a temperature of a heat absorption side of the Peltier element (2) and heat radiation are reduced. Peltier element driving method, comprising detecting a side temperature and controlling a power supply device (1) to control a supply current to a Peltier element (2) based on a difference between a heat radiation side temperature and a heat absorption side temperature. . 2. The Peltier device driving method according to claim 1, wherein the ambient temperature is also detected, and the supply current to the Peltier device is controlled in consideration of the ambient temperature. 3. The method according to claim 1, further comprising detecting a temperature of a control target by the Peltier element and controlling a supply current to the Peltier element in consideration of the temperature of the control target. A method for driving a Peltier device according to any one of the preceding claims. 4. An apparatus for driving a Peltier element (2) by supplying a direct current to the Peltier element (2) by a power supply device (1) (12) (25), wherein the Peltier element (2) is provided. First temperature detecting means (8) for detecting the temperature on the heat-absorbing side and the temperature on the heat-dissipating side, and a power supply device for controlling the current supplied to the Peltier element (2) based on the difference between the temperature on the heat-radiating side and the temperature on the heat absorbing side (1) First power control means for controlling (12) and (25) (6) (11) (13) (24) (2)
6) A Peltier device driving device comprising: 5. A first power supply control means (1) further comprising second temperature detection means (14) (27) for detecting an ambient temperature.
1), (13), (24) and (26) for controlling the power supply devices (12) and (25) to control the supply current to the Peltier element (2) in consideration of the ambient temperature. 4. The Peltier device driving device according to claim 1. 6. A third temperature detecting means (21) for detecting a temperature of a control target by the Peltier element (2), and a power supply device for controlling a current supplied to the Peltier element (2) based on the temperature of the control target. The Peltier device driving device according to claim 4 or 5, further comprising second power supply control means (22) and (23) for controlling (25).