JP2001349681A - Boiling cooling system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify a system by employing only one condenser for cooling a plurality of cooling objects having different demanded cooling characteristics. SOLUTION: The boiling cooling system comprises an evaporator 1a provided for a cooling object A, an evaporator 1b provided for a cooling object B, and one condenser 2 for cooling to liquefy gas-phase refrigerants from the evaporators 1a, 1b wherein a controller 20 regulates the pressure at the gas- phase parts of the evaporators 1a, 1b by controlling the opening of pressure regulation valves 4a, 4b. Since the temperature of the cooling objects A, B can be controlled independently, demanded cooling characteristics of the cooling objects A, B can be satisfied respectively using one condenser.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a boiling cooling system.

[0002]

2. Description of the Related Art A boiling cooling system for cooling an object using heat of vaporization of a refrigerant has been proposed (Japanese Patent Laid-Open No. 6-8852).
No. 3). In such a system, since the refrigerant absorbs a large amount of heat from the object to be cooled when the refrigerant evaporates, a higher cooling effect can be expected as compared with a general cooling method in which the refrigerant is circulated in the liquid phase. .

[0003]

In such a system, the refrigerant which has absorbed heat from the object to be cooled and vaporized is cooled and liquefied in a condenser, and provided in correspondence with the object to be cooled by a pump or the like. Again into the evaporator.

However, in the conventional boiling cooling system, when cooling a plurality of objects having different required cooling characteristics, for example, a target temperature, it is necessary to supply a refrigerant having a different temperature to an evaporator of each object. It is necessary to provide a number of condensers, cooling fans and the like in accordance with the number of objects to be cooled.
Providing a plurality of condensers and cooling fans increases the complexity of the system and increases the manufacturing cost.

The present invention has been made in view of the above-mentioned technical problems of the related art, and provides a single condenser for cooling a plurality of cooling objects having different required cooling characteristics, thereby simplifying the system. With the goal.

[0006]

A first aspect of the present invention relates to a boiling cooling system for cooling a first cooling object and a second cooling object having different required temperature characteristics. , A second evaporator provided for a second object to be cooled, a refrigerant in a gas phase in the first evaporator, and a second evaporator A condenser for cooling and liquefying the refrigerant which has become a gas phase in the above, and a gas phase pressure for independently adjusting the gas phase pressure of the first evaporator and the gas phase pressure of the second evaporator And adjusting means.

[0007] The second invention is the first invention according to the first invention.
A valve is provided in a passage communicating between the evaporator and the condenser, and the gas-phase-portion pressure adjusting means controls the opening of the valve so that the first valve is opened.
The pressure in the gas phase of the evaporator is adjusted.

[0008] The third invention is the second invention, wherein the first
Means for detecting the temperature of the object to be cooled, and the gas phase pressure adjusting means controls the opening of the valve in accordance with the detected temperature of the object to be cooled.

A fourth invention is the second invention, wherein the first invention
Means for detecting the gas phase pressure between the evaporator and the valve, wherein the gas phase pressure adjusting means controls the opening degree of the valve according to the detected gas phase pressure. is there.

In a fifth aspect based on the second aspect, there is provided means for detecting a pressure difference between an upstream side and a downstream side of the valve,
The gas-phase-portion pressure adjusting means controls the opening degree of the valve according to the detected pressure difference.

According to a sixth aspect of the present invention, in the second aspect, a one-way valve is provided between the valve and the condenser, which allows only a flow from the valve side to the condenser side.

According to a seventh aspect, in the sixth aspect, the control temperature range of the first cooling object provided with the one-way valve is smaller than the control temperature range of the second cooling object. Things.

According to an eighth aspect, in the second aspect, a means for introducing a negative pressure between the valve and the condenser is provided.

According to a ninth aspect, in the first aspect, means for superheating refrigerant vapor provided in a passage communicating the first evaporator and the condenser, a turbine rotated by the superheated vapor, and a turbine A rotary electric machine connected thereto, wherein the gas phase pressure adjusting means adjusts the gas phase pressure of the first evaporator by controlling the rotation speed of the turbine using the rotary electric machine. It is.

According to a tenth aspect, the ninth aspect is applied to a fuel cell vehicle having a fuel cell stack and electric parts, wherein a first object to be cooled is a fuel cell stack, and a second object to be cooled is an electric motor. The feature is that it is a part.

According to an eleventh aspect, in the tenth aspect,
It is characterized in that the means for superheating the refrigerant vapor superheats the refrigerant vapor using the heat energy of the exhaust gas of the catalytic combustor for processing carbon monoxide generated in the reformer.

According to a twelfth aspect, in the tenth aspect,
A compressor for pressurizing air supplied to an air electrode of a fuel cell stack is driven by a turbine.

According to a thirteenth aspect, in the twelfth aspect,
The rotary electric machine is used as a motor or a generator so that the rotation speed of the compressor becomes a target rotation speed.

[0019]

In order to cool a plurality of cooling objects having different required cooling characteristics, conventionally, it was necessary to provide a condenser for each evaporator of each cooling object, but in the boiling cooling system according to the present invention, Since the temperature of each cooling object is adjusted by adjusting the gas phase pressure of the evaporator, there is no need to supply a refrigerant at a different temperature to each evaporator, and the condenser, cooling fan, etc. are shared by each evaporator. (First invention). Thereby, the system configuration can be simplified as compared with a conventional system provided with a plurality of condensers, and the manufacturing cost can be reduced.

The adjustment of the pressure in the gas phase is performed, for example, by controlling the opening (or duty ratio) of a valve (butterfly valve, solenoid valve, etc.) provided in a passage connecting the evaporator and the condenser. (Second invention). Thus, for example, when the temperature of the object to be cooled is high, the valve opening is controlled to a large side, and if the gas phase pressure of the evaporator is reduced, vaporization of the refrigerant in the evaporator is promoted, and the temperature of the object to be cooled is reduced. (Third invention).

Alternatively, since the gas phase pressure changes according to the temperature of the object to be cooled, the valve opening may be controlled according to the gas phase pressure to control the temperature of the object to be cooled. Good (fourth invention).

When the pressure difference between the upstream side and the downstream side of the valve is small, the circulation speed of the refrigerant becomes slow, and it takes time for the temperature of the object to be cooled to reach the target temperature. If the correction is made according to the pressure difference, the temperature of the object to be cooled can be quickly brought close to the target temperature even when the pressure difference is small (fifth invention).

If a one-way valve is provided between the valve and the condenser, the temperature of the other object to be cooled becomes high, and high-pressure refrigerant vapor flows from the evaporator into the condenser, and Can be prevented from flowing between the valve and the one-way valve even if the pressure of the air becomes high (sixth invention).
Thus, the pressure difference between the upstream side and the downstream side of the valve can always be kept large, and the object to be cooled can be quickly brought close to the target temperature. It is to be noted that such a one-way valve is preferably provided in a place where the control temperature range of the object to be cooled is narrow and it is necessary to quickly approach the target temperature (seventh invention).

If a negative pressure introducing means such as a vacuum tank is provided between the valve and the condenser, if it is necessary to quickly bring the temperature of the object to be cooled to the target temperature, a negative pressure is applied to the downstream side of the valve. By introducing, the pressure difference between the upstream side and the downstream side of the valve can be increased (eighth invention).

The pressure in the gas phase of the evaporator is adjusted by providing a means for heating the steam between the evaporator and the condenser and a turbine, and controlling the rotation speed of the turbine using a rotating electric machine. Is also possible (ninth invention).

Further, such a boiling cooling system can be applied to, for example, a fuel cell vehicle (FCV). In this case, the first cooling object is a fuel cell stack, and the second cooling object is a driving motor. (10th invention).

Further, when applied to a fuel cell vehicle, the efficiency of the system can be improved by generating superheated steam for driving the turbine by using the thermal energy of the exhaust gas of the reformer catalytic combustor. (Eleventh invention).

Further, if the compressor for pressurizing the air sent to the air electrode of the fuel cell stack is driven by the turbine for adjusting the steam pressure, the driving energy of the compressor becomes unnecessary (twelfth invention). If the rotation speed of the compressor is controlled using the rotating electric machine connected to the turbine, the efficiency of the system can be further improved (a thirteenth invention).

[0029]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows a schematic configuration of a boiling cooling system according to the present invention. This cooling system is for cooling two objects to be cooled A and B having different management temperatures. Evaporators 1a and 1b are provided inside (or near) the objects to be cooled A and B, respectively. I have.

The evaporators 1a and 1b are respectively connected to communication pipes 3a,
3b and the communication pipes 7a and 7b are connected to the condenser 2 to form a closed system, and the refrigerant C circulates between the evaporators 1a and 1b and the condenser 2 while changing the phase.

The communication pipe 3a connecting the gaseous side of the evaporator 1a and the gaseous side of the condenser 2 is provided with a pressure regulating valve 4a and a bypass passage 5a for bypassing the pressure regulating valve 4a. A relief valve 6a is provided in the passage 5a. In addition, a communication pipe 7a connecting the liquid side of the evaporator 1a and the liquid phase side of the condenser 2 has a condenser 2 from the evaporator 1a.
Is provided with an electronically controlled pump 8a for controlling the amount of refrigerant C to be sent.

Similarly, a pressure regulating valve 4b and a bypass passage 5b are provided in a communication pipe 3b connecting the gaseous side of the evaporator 1b and the gaseous side of the condenser 2, and a relief passage is provided in the bypass passage 5a. A valve 6b is provided. A communication pipe 7 connecting the liquid side of the evaporator 1b and the liquid side of the condenser 2 is provided.
b is provided with an electronic control pump 8b.

The evaporators 1a and 1b are provided with wall temperature sensors 10a and 10b for detecting the wall temperature of the evaporation container and liquid level sensors 11a and 11b for detecting the liquid level of the refrigerant. The surface sensors 11a and 11b output an ON signal when the liquid level reaches a predetermined level.

Further, between the evaporator 1a and the pressure regulating valve 4a,
An evaporator 1 is provided between the evaporator 1b and the pressure regulating valve 4b.
pressure sensors 12a, 12b for detecting the pressures of the gaseous phase portions a, 1b (upstream pressures of the pressure regulating valves 4a, 4b)
The condenser 2 is provided with a pressure sensor 15 for detecting the pressure in the gas phase (downstream pressures of the pressure regulating valves 4a and 4b) and a cooling fan 16 for cooling the condenser 2. ing. Further, the cooling objects A and B are provided with temperature sensors 17a and 17b for detecting the temperatures of the objects, respectively.

The controller 20 is a microprocessor,
The wall temperature sensors 10a and 10b, the liquid level sensors 11a and 11b,
Pressure sensors 12a, 12b, 15, temperature sensor 17a,
In addition to the signal from 17b, the accelerator operation amount signal, the opening degree signals of the pressure regulating valves 4a and 4b, the rotation speed signals of the electronically controlled pumps 8a and 8b, the rotation speed signal of the cooling fan 16, and the like are input. The controller 20 determines the cooling state of each of the cooling objects A and B based on these various signals, and controls the pressure regulating valves 4a and 4b so that the temperatures of the cooling objects A and B become the target temperatures.
4b, and control the electronically controlled pumps 8a and 8b.

Specifically, the controller 20 controls the electric pump 8a based on the output of the liquid level sensor 11a to control the liquid level of the evaporator 1a to be constant. Further, when it is determined based on the output of the temperature sensor 17a that the temperature of the object A is lower than the target temperature, the opening of the pressure control valve 4a is increased to reduce the pressure of the gas phase of the evaporator 1a, and The vaporization is promoted to lower the temperature of the object A. Conversely, when it is determined that the temperature of the target A is higher than the target temperature, the opening of the pressure regulating valve 4a is narrowed to increase the pressure in the gaseous phase portion of the evaporator 1a, thereby suppressing the vaporization of the refrigerant and the target. The temperature of the object A is increased.

The same control is performed for the object B to be cooled. The controller 20 controls the liquid level of the evaporator 1b based on the output of the liquid level sensor 11b, and controls the pressure control valve 4b based on the output of the temperature sensor 17b. Is adjusted, and the temperature of the object B is controlled to the target temperature.

FIG. 2 is a flowchart showing the contents of the temperature control performed by the controller 20. This is for controlling the temperature of the cooling target A to the target temperature, and the same temperature control is also performed for the cooling target B.

To explain this, first, in step S
In 1, the operation state of the system (the output of the liquid level sensor 11a,
The temperature Ta of the object A and the opening degree θa) of the pressure regulating valve 4a are read.

Next, in steps S2 to S4, it is determined whether or not the liquid level sensor 11a is ON. And sensor 1
When 1a is ON, the electronic control pump 8a is stopped to lower the liquid level (S4), and when OFF, the electronic pump 8b is driven to increase the liquid level (S3).
The liquid level in the evaporator 1a is kept constant.

In step S5, a temperature difference ΔTa between the temperature Ta of the object A and the target temperature T0a is calculated, and in step S5,
At 6, it is determined whether the magnitude of the temperature difference ΔTa is equal to or greater than a predetermined value dTtha. As a result of the determination, when the magnitude of the temperature difference ΔTa is equal to or more than the predetermined value dTtha, the difference between the target temperature Ta and the target temperature T0a is large, so the process proceeds to step S7 and thereafter, and the pressure adjustment is performed so that the target temperature Ta approaches the target temperature T0a. The opening of the valve 4a is adjusted.

In step S7, based on the magnitude of the temperature difference ΔTa, referring to the table shown in FIG. 3, the opening correction amount Δθa
Is calculated, and when the temperature difference ΔTa is larger than zero, that is, when the target object temperature Ta is higher than the target temperature T0a, the process proceeds to step S9, and the opening of the pressure regulating valve 4a is corrected to a large side. On the other hand, when the temperature difference ΔTa is smaller than zero, that is, when the temperature Ta of the object is lower than the target temperature T0a, the process proceeds to step S10, and the opening of the pressure regulating valve 4a is corrected to a small side.

If it is determined in step S6 that the temperature difference ΔTa is smaller than the predetermined value dTtha, the temperature Ta of the object to be cooled is close to the target temperature Ta0. Degree θa is maintained.

Next, the effect of performing such control will be described.

In this embodiment, the object to be cooled is cooled by utilizing the heat of vaporization of the refrigerant in the evaporator (1a, 1b). Therefore, the cooling effect of the object to be cooled is reduced by the vaporization of the refrigerant in the evaporator. Depends on how easy it is to do. That is, when the refrigerant is easy to vaporize, more heat of vaporization is taken from the object, so that the cooling effect is enhanced. Conversely, when it is difficult to vaporize, the heat of vapor taken away from the object is reduced, and the cooling effect is reduced.

Therefore, in the present invention, when the temperature of the object to be cooled is higher than the target temperature, the pressure regulating valves (4a, 4b) are opened, the pressure in the evaporator is reduced, and the vaporization is promoted.
Conversely, when the temperature is lower than the target temperature, the pressure regulating valve is opened, and the pressure in the evaporator is increased to suppress the vaporization of the refrigerant.

As a result, the object to be cooled can be controlled to the target temperature. However, the temperature of the object to be cooled is controlled by controlling the pressure of the gas phase, and the temperature is controlled independently of the temperature of the refrigerant sent to the evaporator. Therefore, as shown in FIG. 1, there are a plurality of cooling objects A and B, and a common condenser can be used for the cooling objects A and B even when their target temperatures are maintained.

As described above, by applying the present invention, the condensers can be integrated into one, so that the system can be simplified as compared with the case where a plurality of condensers are provided, and the manufacturing cost can be reduced. it can. In particular, when the present system is applied to a vehicle, the volume of the system is reduced, which is advantageous in terms of mountability.

Further, when the condensers are integrated into one, there is an advantage that the capacity required for the condenser can be reduced as compared with the case where the condensers are provided for the respective objects to be cooled.
In other words, when a condenser is provided for each object, each condenser must have a capacity corresponding to the maximum amount of heat radiation of the object, but when one condenser is used, the amount of heat radiation of the object It is sufficient if the load corresponding to the peak of the heat radiation amount of each object is shifted as shown in FIG. 4 if the condenser corresponding to the maximum value of the sum of The total capacity of the condenser can be reduced as compared with ((A + B) max ≦ Amax + Bmax).

Although the case where there are two objects to be cooled is shown here, the condenser can be integrated into one by adopting the same configuration when there are three or more objects to be cooled.

Although the butterfly valves are provided here as the pressure regulating valves 4a and 4b, a solenoid valve or the like may be provided if necessary. In this case, the gas phase pressure is adjusted by controlling the duty ratio.

Further, here, the temperature is controlled based on the detected temperature of the cooling object so that the temperature of the object becomes the target temperature. However, the temperature of the gas phase portion of the evaporator detected by the pressure sensors 12a and 12b is controlled. Temperature control may be performed according to the pressure. When the temperature of the target is high, the gas phase pressure increases, and when the temperature of the target is low, the gas phase pressure decreases.
Even if the opening degree of b is controlled, the target object temperature can be controlled to the target temperature.

Next, a second embodiment will be described.

This embodiment is different from the first embodiment in the method of calculating the opening correction amount of the pressure regulating valve. Hereinafter, a description will be given mainly of a portion different from the first embodiment.

FIG. 5 is a flowchart showing the contents of the temperature control performed by the controller 20, which is executed in place of the one shown in FIG. Here, only the temperature control of the cooling target A is shown, but the same temperature control is performed for the cooling target B as well.

The operation in each step will be described. First, in step S21, the operation state is read in the same manner as in the previous embodiment. Here, the output of the liquid level sensor 11a, the temperature Ta of the object A and the pressure control valve 4a Opening θa
In addition, the pressure Pua on the upstream side and the pressure Pda on the downstream side of the pressure regulating valve 4a are read. Then, step S22
In steps S24 to S24, the electronic control pump 8a is controlled based on the output of the liquid level sensor 11a, and the liquid level in the evaporator 1a is kept constant.

In step S25, a temperature difference ΔTa between the temperature Ta of the object A and its target temperature T0a is calculated, and in step S26, the temperature difference ΔTa is compared with a predetermined value dTtha. When the temperature difference ΔTa exceeds the predetermined value dTtha, the process proceeds to step S27 and the opening of the pressure regulating valve 4a is controlled. At this time, the temperature difference ΔTa
And the pressure difference ΔP between the upstream side and the downstream side of the pressure regulating valve 4a.
a (= Pua−Pda) in consideration of the pressure regulating valve opening θa.
Is calculated (step S7).

Specifically, the correction amount Δθa is determined by the temperature difference ΔTa
Is calculated with reference to the map shown in FIG. 6 based on the pressure difference ΔPa and the temperature difference ΔTa.
As Pa decreases, a larger value is calculated as the correction amount Δθa, and the opening of the pressure regulating valve 4a is controlled based on the larger value (steps S28 to S30).

Therefore, in this embodiment, as in the previous embodiment, when the temperature of the object to be cooled is higher than the target temperature, the pressure regulating valves (4a, 4b) are closed, and conversely, when the temperature of the object to be cooled is lower than the target temperature. When the pressure is too low, the pressure regulating valve is opened to control the temperature of the object to be cooled. However, when the pressure difference between the upstream side and the downstream side of the pressure regulating valve is small, the pressure regulating valve is widely opened. Thereby, even if the pressure difference is small, the circulation amount of the refrigerant is increased, and the temperature of the object to be cooled can be quickly brought close to the target value.

FIG. 7 shows a third embodiment.

In this embodiment, a one-way valve 30 that allows only a flow from upstream to downstream is provided downstream of the pressure regulating valve 4a.
The difference from the first embodiment is that a is provided.

By providing such a one-way valve 30a, even if the object B to be cooled has a high temperature and a large amount of steam is generated in the evaporator 1b and the inside of the condenser 2 has a high pressure, the high pressure Does not flow between the pressure regulating valve 4a and the one-way valve 30a, and the pressure between the pressure regulating valve 4a and the one-way valve 30a can be maintained at a low pressure. As a result, the pressure difference ΔP between the upstream side and the downstream side of the pressure regulating valve 4a can always be increased, and the temperature of the cooling target A can reach the target temperature more quickly.

The one-way valve is provided on the side where the allowable temperature range (dTtha in FIG. 2) of the object to be cooled is small (here, the object A side), but is provided on both sides of the objects A and B. You may.

FIG. 8 shows a fourth embodiment.

This embodiment includes a vacuum tank 31 connected to a negative pressure source (for example, an intake pipe of an engine), and a negative pressure introducing valve 32. When the negative pressure introducing valve 32 is opened, the pressure regulating valve 4a is opened. The third embodiment differs from the third embodiment in that a negative pressure can be introduced between the third embodiment and the check valve 30a.

Such a negative pressure introducing means is connected to the pressure regulating valve 4a.
When it is necessary to quickly cool the object to be cooled due to a sudden increase in load or the like, by opening the negative pressure introducing valve 32 and introducing a negative pressure, the pressure regulating valve 4a is provided.
The pressure difference ΔP before and after becomes large, and the temperature of the cooling object A can reach the target temperature more quickly.

FIG. 9 shows a fifth embodiment.

In this embodiment, instead of the pressure regulating valve 4a in the first embodiment, there is provided a turbine 35 which rotates by receiving refrigerant vapor, and a rotary electric machine 36 for controlling the rotation speed of the turbine 35. And a superheater 37 for superheating the saturated steam from the evaporator 1a into superheated steam on the upstream side of the turbine 35.

Even in such a configuration, the pressure of the gas phase portion of the evaporator 1a can be adjusted by adjusting the rotation speed of the turbine 35 using the rotating electric machine 36. The temperature of the object can be controlled.

In this case, since the pressure of the condenser 2 increases, a one-way valve 30b is provided on the cooling object B side.
Further, this configuration is adopted on the side where the amount of heat generated by the evaporator is large (here, the cooling object A side), but this configuration may be used for both the objects A and B.

FIG. 10 shows an example in which the system shown in FIG. 9 is applied to a methanol reforming fuel cell vehicle (FCV) (sixth embodiment). Components corresponding to the system shown in FIG. 9 are given the same reference numerals.

In this vehicle, hydrogen obtained by reforming methanol in the reformer 41 is supplied to the fuel electrode 43 of the fuel cell stack 42 composed of a plurality of fuel cells, and the air in the fuel cell stack 42 is Electric power is generated by supplying air to the poles 44, and the generated electric power drives an electric motor (motor / generator) 45. The carbon monoxide generated during the reforming process is converted into the catalytic reformer 47.
Purified in

Here, the objects A and B to be cooled in the system shown in FIG. 9 are respectively transferred to the fuel cell stack 42, the electric motor 45 and the power control unit 4 for controlling the electric motor 45.
6, which is cooled down during operation. The controller 20 controls the turbine rotation speed and the opening of the pressure regulating valve, respectively, so that those temperatures become target temperatures set according to the operating conditions.

The superheated steam for driving the turbine 35 is generated by superheating the refrigerant, which has been saturated by the heat generated by the fuel cell stack 42, with the high-temperature exhaust gas exhausted by the catalytic combustor 47. (Corresponds to the superheater 37).

Since the efficiency of the fuel cell stack 42 is higher as it is operated at a higher pressure, the air supplied to the air electrode 44 is pressurized by the compressor 50. The compressor 50 is provided coaxially with the turbine 35. , Turbine 3
With the configuration driven by 5, the means for driving the compressor 50 becomes unnecessary, and there is no need to supply kinetic energy to the compressor 50, so that the thermal efficiency can be improved.

Although the heat generation amount of the fuel cell stack 42 and the required supply air amount (target rotation speed) of the compressor 50 are basically in a proportional relationship, in a load transient condition when the rotating electric machine 36 is turned off, A time lag or excess or deficiency occurs between the target rotation speed and the actual rotation speed. Therefore, by using the rotating electric machine 36 as a motor or a generator as shown in FIG. 11 and controlling the rotating speed of the compressor 50 to a target rotating speed, the efficiency of the system can be further enhanced.

FIG. 12 shows the contents of the switching control of the rotating electric machine performed by the controller 20 in this case.
According to this, it is determined whether or not the speed difference ΔN between the rotation speed N of the rotary electric machine 36 and the target rotation speed N0 is larger than the allowable variation width c (S51 to S53). The function of the rotating electric machine 36 is switched to a motor or a generator according to the sign of ΔN, and the speed difference ΔN is absorbed (S54 to S56).

Although the embodiment of the present invention has been described above, the configuration shown here is merely an example of a configuration to which the present invention can be applied, and does not limit the scope of the present invention. INDUSTRIAL APPLICABILITY The present invention can be widely applied to a boiling cooling system that cools a plurality of objects to be cooled having different required cooling characteristics, and effects such as system simplification and cost reduction can be expected.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a boiling cooling system according to the present invention.

FIG. 2 is a flowchart showing the contents of temperature control.

FIG. 3 is a map for calculating an opening correction amount of a pressure regulating valve.

FIG. 4 is a diagram showing the capacity required for a condenser when a condenser is provided for each evaporator and when the condensers are combined into one.

FIG. 5 is a flowchart showing a second embodiment of the present invention.

FIG. 6 is a map for calculating an opening correction amount of a pressure regulating valve in a second embodiment.

FIG. 7 is a schematic configuration diagram of a third embodiment of the present invention.

FIG. 8 is a schematic configuration diagram of a fourth embodiment of the present invention.

FIG. 9 is a schematic configuration diagram of a fifth embodiment of the present invention.

FIG. 10 is a schematic configuration diagram of a sixth embodiment of the present invention.

FIG. 11 is a diagram for explaining control contents of the rotating electric machine.

FIG. 12 is a flowchart showing the contents of switching control of the rotating electric machine.

[Explanation of symbols]

 1a, 1b Evaporator 2 Condenser 4a, 4b Pressure control valve 8a, 8b Electrically controlled pump 11a, 11b Liquid level sensor 12a, 12b Pressure sensor 15 Pressure sensor 17a, 17b Temperature sensor 20 Controller 30a, 30b One-way valve 31 Vacuum tank 32 Negative pressure introduction valve 35 Turbine 36 Rotating electric machine 37 Superheater 41 Reformer 42 Fuel cell stack 45 Electric motor 46 Power control unit 47 Catalytic combustor 50 Compressor

Claims (13)

[Claims] 1. A boiling cooling system for cooling a first cooling object and a second cooling object having different required temperature characteristics, wherein a first evaporation provided for the first cooling object. A second evaporator provided for the second object to be cooled, a refrigerant in a gaseous phase in the first evaporator, and a refrigerant in a gaseous phase in the second evaporator. A condenser for cooling and liquefying the gas, and a gas-phase pressure adjusting means for independently adjusting a gas-phase pressure of the first evaporator and a gas-phase pressure of the second evaporator. A boiling cooling system. 2. A control device comprising: a valve in a passage communicating the first evaporator and the condenser; wherein the gas-phase-portion adjustment control means controls an opening degree of the valve to control the first evaporator. 2. The boiling cooling system according to claim 1, wherein the pressure in the gas phase is adjusted. 3. A device for detecting the temperature of the first object to be cooled, wherein the gas phase pressure adjusting means controls the opening of the valve according to the detected temperature of the object to be cooled. The boiling cooling system according to claim 2, characterized in that: 4. A means for detecting a gas phase pressure between the first evaporator and a valve, wherein the gas phase pressure adjusting means opens and closes the valve in accordance with the detected gas phase pressure. The boiling cooling system according to claim 2, wherein the degree is controlled. 5. A means for detecting a pressure difference between an upstream side and a downstream side of the valve, wherein the gas phase pressure adjusting means controls an opening degree of the valve according to the detected pressure difference. 3. The boiling cooling system according to claim 2, wherein: 6. The boiling cooling system according to claim 2, wherein a one-way valve is provided between the valve and the condenser to allow only a flow from the valve side to the condenser side. 7. The boiling cooling according to claim 6, wherein the control temperature range of the first cooling object provided with the one-way valve is narrower than the control temperature range of the second cooling object. system. 8. A boiling cooling system according to claim 2, further comprising means for introducing a negative pressure between said valve and a condenser. 9. A device provided in a passage communicating between the first evaporator and the condenser for superheating refrigerant vapor, a turbine rotating by the superheated vapor, and a rotating electric machine connected to the turbine. The gas-phase part pressure adjusting means adjusts a gas-phase part pressure of the first evaporator by controlling a rotation speed of the turbine by using the rotating electric machine. Boiling cooling system. 10. A fuel cell vehicle having a fuel cell stack and electric parts, wherein the first object to be cooled is the fuel cell stack, and the second object to be cooled is the electric part. The boiling cooling system according to claim 9, wherein: 11. The boiling cooling system according to claim 10, wherein said means for superheating the refrigerant vapor superheats the refrigerant vapor using thermal energy of exhaust gas from a reformer catalytic combustor. 12. The boiling cooling system according to claim 10, wherein a compressor that pressurizes air supplied to an air electrode of the fuel cell stack is driven by the turbine. 13. The boiling cooling system according to claim 12, wherein the rotating electric machine is used as a motor or a generator so that a rotation speed of the compressor becomes a target rotation speed.