JPH0443568A - Fuel cell - Google Patents

Abstract

PURPOSE:To enable the stable control of fuel cell cooling water temperature, and ensure waste heat recovery without a loss by performing the proportional control of a flow control electric valve, or the speed of a pump and a blower on the basis of cooling water temperature therefor. CONSTITUTION:The outlet of a waste heat recovery heat exchanger 7 for a cell cooling and waste heat recovery pipe 5 is fitted with a water flow control electric valve 15 allowing the proportional opening control. A controller 18A selects the predetermined control method to suit generated current on the basis of the generated current detected with a generated current detection means 14. Then, the controller 18A controls the electric valve 15, according to cooling water temperature detected with a cooling water temperature detection means 13. When the cooling water temperature rises, regardless of the maximum opening of the electric valve 15, the speed of a blower 11 for an outdoor waste heat exchanger 10 is controlled, with the opening of the valve 15 kept maximum. According to the aforesaid construction, the cooling water temperature can be stably controlled with the proportional band of the electric valve 15 and the blower 11 kept narrow, when a generated heating value at a cell stack 3 is high. When the aforesaid value is low, the cooling water temperature can be similarly controlled with the aforesaid proportional band kept wide.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a fuel cell, and more particularly to a method for controlling the temperature of fuel cell cooling water.

[Conventional technology]

FIG. 11 is a diagram showing the basic configuration of a conventional example of a fuel cell.

The fuel cell ID is a reformer 2 that produces hydrogen from city gas.
, a battery stack 3, an electric output section 4, a steam separator 6 for separating water vapor from the cooling water of the battery stack 3, a cooling water temperature detection means 13 provided in the steam water separator 6, and a battery cooling To the circulating pump 26 for dual exhaust heat recovery, the heat exchanger 7 for exhaust heat recovery, the heat exchanger 10 for outdoor exhaust heat, the battery cooling/exhaust heat recovery system piping 5, and the heat exchanger 10 for outdoor exhaust heat Solenoid valves 8 and 9 for controlling the amount of cooling water of
, a rotation control means 17 for the blower 11, a controller 18D that detects a signal from the cooling water temperature detection means 13 via wiring 19, controls the opening/closing control means 16, and the rotation control means 18, and is used for exhaust heat recovery. The absorption refrigerator 12 connected to the heat exchanger 7 by the absorption refrigerator system piping 20 uses the exhaust heat recovered by the exhaust heat recovery heat exchanger 7 as a heat source.

Next, the function of cell cooling and exhaust heat recovery of this fuel cell ID will be explained.

The cooling water that has removed the heat generated in the battery stack 3 of the fuel cell ID is led to the steam/water separator 6, and then to the heat exchanger 7 for exhaust heat recovery or the heat exchanger 10 for outdoor exhaust heat, and then The heat generated in the stack 3 can be used as a heat source for the absorption chiller 12, or if the heat cannot be used, it can be used as an outdoor exhaust heat exchanger 10.
It is vented outdoors. Here, the blower 11 of the outdoor heat exchanger 10 is controlled on/off.

FIG. 12 is a diagram showing an example of cooling water temperature fluctuation when the amount of heat generated from the battery stack 3 is large and the amount of heat used is also large.

When the temperature of the cooling water rises from T1 to T2, the solenoid valve 9 is opened so that the cooling water passes through the exhaust heat recovery heat exchanger 7, and at the same time, the solenoid valve 8 is closed. and perform heat recovery. This causes the cooling water temperature to drop.
When the temperature reaches 1, the solenoid valve 9 is closed, and at the same time, the solenoid valve 8 is opened to prevent the cooling water temperature from decreasing. In this case, the blower 11 of the outdoor heat exchanger 10 is stopped.

FIG. 13 is a diagram showing an example of fluctuations in cooling water temperature when the amount of heat generated from the battery stack 3 is large but the amount of heat used is small.

When the cooling water temperature rises and reaches T2,
As in the case of Fig. 12, the cooling water is transferred to the exhaust heat recovery heat exchanger 7.
Open the solenoid valve 9 so that the
Close and perform heat recovery. However, since the battery stack 3 generates a large amount of heat and only a portion of the heat can be recovered, the cooling water temperature continues to rise. Therefore, when the cooling water temperature further increases to the temperature T3, the blower 11 of the outdoor exhaust heat heat exchanger 10 is operated to exhaust the exhaust heat outdoors. When the temperature of the cooling water decreases due to exhaust to the outdoors and reaches the temperature T2, the operation of the blower 11 of the heat exchanger 10 for outdoor exhaust heat is stopped to stop exhaust heat to the outdoors.

On the other hand, the amount of heat generated in the battery stack 3 is proportional to the power generation output. FIG. 14 is a diagram showing the relationship between the power generation output and the amount of heat generated in the battery stack 3. In FIG. 14, 31 shows the amount of heat that can be used as exhaust heat out of the amount of heat generated in the battery stack 3, and 32 shows the amount of heat that is consumed inside the fuel cell out of the amount of heat generated as exhaust heat. If the heat generated in the battery stack 3 is recovered and exhausted outdoors in the same manner as when the amount of heat generated is small, the following problems occur.

In Fig. 15, the amount of heat generated from the battery stack 3 is small, but
It is a figure which shows the fluctuation of the cooling water temperature when the amount of heat used is large.

When the cooling water temperature rises and reaches T2,
As in the case of Fig. 12, the cooling water is transferred to the exhaust heat recovery heat exchanger 7.
Open the solenoid valve 9 so that the
Close and perform heat recovery. However, since the amount of heat generated by the battery stack 3 is small, immediately after the electromagnetic valve 9 is opened and exhaust heat recovery is started, the cooling water temperature drops rapidly, and the cooling water temperature also falls below the allowable lower limit value TL. Cooling water temperature is at the allowable lower limit TL
If the pressure of the cooling water decreases, a portion of the cooling water inside the battery stack 3 boils, and the battery stack 3 is no longer cooled, causing the batteries constituting the battery stack 3 to become heated due to local heating. to degrade.

FIG. 16 is a diagram showing fluctuations in cooling water temperature when the amount of heat generated from the battery stack 3 is small and the amount of heat used is also small.

When the cooling water temperature rises and reaches T2,
As in the case of Fig. 12, the cooling water is transferred to the exhaust heat recovery heat exchanger 7.
Open the solenoid valve 9 so that the
is closed to recover heat, but the temperature of the cooling water continues to rise because the amount of heat used is small. Therefore, when the cooling water temperature further increases to the temperature T3, the blower 11 of the outdoor exhaust heat heat exchanger 10 is operated to exhaust the exhaust heat outdoors. However, since the blower 11 is controlled on/off, when the blower 11 starts operating, the cooling water temperature drops rapidly due to the large air volume, which not only makes it impossible to use heat by recovering exhaust heat, but also increases the cooling water temperature. below the allowable lower limit TL.

Note that the solenoid valves 8.9 are electrically operated valves, and these electrically operated valves 8.9 are electrically operated valves.
9 and the blower 11 may be controlled proportionally,
The proportional band of this proportional control is simply the generated current of the fuel cell ID,
That is, if the amount of heat generated from the battery stack 3 is kept constant regardless of the amount, the following problem will occur.

First, if the proportional band is set narrowly regardless of the amount of heat generated by the battery stack 3, it becomes close to on/off control, and when the amount of heat generated by the battery stack 3 is small, the cooling water temperature will change as shown in Figs. 15 and 16. Fluctuations similar to those explained in the diagram may occur, and exhaust heat recovery may not be sufficient, or the cooling water temperature may be at the allowable lower limit T.
Go below L. Next, if the proportional band is set to be wide regardless of the amount of heat generated by the battery stack 3, the response of the blower 11 will be Due to poor cooling water temperature, it rises and exceeds the allowable upper limit.

(Problem to be Solved by the Invention) In the conventional fuel cell described above, even when the amount of heat generated by the fuel cell is small, the amount of cooling water passing through the heat exchanger for exhaust heat recovery is controlled using the same control method as when the amount of heat generated is large. As a result, the cooling water temperature fluctuated significantly and the temperature of the cooling water fell below the allowable lower limit, causing the batteries in the battery stack to fail. There were drawbacks such as deterioration and waste heat that should be recovered being discharged outdoors.

An object of the present invention is to provide a fuel cell that allows stable control of cell cooling water temperature and waste heat recovery.

Means for Solving Problem C8] A first fuel cell of the present invention includes: a reformer that produces hydrogen from fuel; a cell stack; and a steam-water separator that separates water vapor from cooling water of the cell stack. , an electric output section, a heat exchanger for exhaust heat recovery, a heat exchanger for outdoor exhaust heat, a cooling water temperature detection means provided in the steam water separator, and a cooling water temperature detection means provided in the steam water separator, from the battery stack to the steam water separator, A valve is provided at the inlet or outlet portion of the exhaust heat recovery heat exchanger of the battery cooling/exhaust heat recovery system piping that passes through the exhaust heat recovery heat exchanger and the outdoor exhaust heat heat exchanger and returns to the battery stack. a water flow control motor-operated valve whose opening degree can be controlled proportionally; a blower for the outdoor exhaust heat heat exchanger whose rotational speed can be controlled proportionally; a generated current detection means provided in the electric output section; Signals are input from the cooling water temperature detection means and the generated current detection means, and the opening degree of the water flow control electric valve and the rotation speed of the blower of the outdoor heat exchanger are detected by the cooling water temperature detection means. Proportional control is carried out based on the cooling water temperature measured by the above, and at this time, the proportional band of the proportional control is narrowed when the generated current measured by the generated current detection means is large, and widened when the generated current is small. and a controller.

A second fuel cell of the present invention includes: a reformer that produces hydrogen from fuel; a cell stack; a steam separator that separates water vapor from cooling water of the cell stack; an electric output section; and exhaust heat recovery. a heat exchanger for outdoor exhaust heat; a cooling water temperature detection means provided in the steam/moisture M device; An electric valve is installed at the outlet or outlet of the heat exchanger for exhaust heat recovery in the absorption chiller system piping that returns to the heat exchanger, and is equipped with an electric valve for water flow control that can proportionally control the valve opening and proportionally control the rotation speed. a blower of the outdoor exhaust heat heat exchanger, which is possible, a generated current detection means provided in the electric output section, a signal from the cooling water temperature detection means and the generated current detection means, and the amount of water is determined by inputting signals from the cooling water temperature detection means and the generated current detection means. The opening degree of the control electric valve and the rotation speed of the blower of the outdoor heat exchanger are proportionally controlled based on the cooling water temperature measured by the cooling water temperature detection means, and at this time, the proportional control and a controller that narrows the proportional band when the generated current measured by the generated current detecting means is large, and widens it when the generated current is small.

A third fuel cell of the present invention includes: a reformer that produces hydrogen from fuel; a cell stack; a steam separator that separates water vapor from cooling water of the cell stack; an electric output section; and exhaust heat recovery. a heat exchanger for outdoor exhaust heat; a cooling water temperature detection means provided in the steam/water separator; and a heat exchanger for recovering exhaust heat from the steam/water separator to the outdoor exhaust heat. an exhaust heat recovery circulation pump that is installed in the exhaust heat recovery system piping that passes through the water exchanger and reaches the steam water separator, and whose rotation speed can be controlled proportionally; Signals are input from the blower of the heat exchanger, the generated current detecting means provided in the electric output section, the cooling water temperature detecting means, and the generated current detecting means to control the exhaust heat recovery circulation pump. rotation speed and
The rotation speed of the blower of the outdoor heat exchanger is proportionally controlled based on the cooling water temperature measured by the cooling water temperature detection means, and at this time, the proportional band of the proportional control is controlled by the generated current detection. and a controller that narrows the current when the generated current measured by the means is large and widens it when the generated current is small.

[Effect]

The present invention provides an electric valve for water flow control provided in a cell cooling/exhaust heat recovery system piping or an absorption chiller system piping of a fuel cell, or a rotation speed of an exhaust heat recovery circulation pump provided in an exhaust heat recovery system piping. Then, the rotation speed of the blower of the outdoor heat exchanger is proportionally controlled based on the cooling water temperature measured by the cooling water temperature detection means, and at this time, the proportional band for proportional control is
When the generated current measured by the generated current detection means of the fuel cell, that is, the amount of heat generated in the cell stack is large, the width is narrowed, and when it is small, the width is widened.

However, since the temperature of the cooling water is constant regardless of the amount of heat generated by the battery stack, the cooling water temperature may fall below the allowable lower limit or exceed the allowable upper limit, causing battery deterioration. Without this, waste heat can be recovered stably, and there is no need to exhaust waste heat outdoors.

Further, in the case of the third fuel cell, when the amount of heat generated from the cell stack is small, the rotation speed of the circulation pump for exhaust heat recovery becomes small, so the power required for controlling the cooling water temperature can be saved.

Note that, instead of detecting the temperature of the cooling water in the steam-water separator, the pressure inside the steam-water separator may be detected to perform similar control.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a configuration diagram of a fuel cell according to a first embodiment of the present invention, FIG. 2 is a diagram showing an example of setting the proportional band of the controller 18A when the amount of heat generated from the battery stack 3 is large, and FIG. 4 is a diagram showing an example of setting the proportional band of the controller 18A when the amount of heat generated from the battery stack 3 is small. FIG. Figures 5 to 8 showing the relationship with efficiency are diagrams showing temporal fluctuations in battery cooling water temperature in this example.

The fuel cell IA of this embodiment includes a battery stack 3, a steam/water separator 6, an exhaust heat recovery heat exchanger 7, and an outdoor exhaust heat heat exchanger 1.
At the outlet of the exhaust heat recovery heat exchanger 7 of the battery cooling/exhaust heat recovery system piping 5 that returns to the battery stack 3 through the 8.
9 and the controller 18A.
The cooling water Proportional control is performed based on the cooling water temperature measured by the temperature detecting means 13, and at that time, the proportional band of the proportional control is narrowed when the generated current measured by the generated current detecting means 14 is larger. The difference from the conventional example shown in FIG. 11 is that it is made wider when it is small.

The controller 18A has a control method shown in FIG. 2, a control method shown in FIG. 3, or a proportional band between FIGS. 2 and 3 based on the generated current detected by the generated current detection means 14. Select a control method. In other words, if the generated current is large, use the control method shown in Figure 2, if the generated current is small, use the control method shown in Figure 3, and if the generated current is between these, use the control method shown in Figures 2 and 3. Select a control method with an intermediate proportional band. In addition, in Figures 2 and 3, (T5-74) < (T9-78), (T7-T
6)<(T7-TIO)T4<T5<T6<T7
．． T8<T9<Ding] 0 <Ding 7.

Regardless of whether you select the control method shown in Fig. 2 or 3, or which has a proportional band between Figs. 2 and 3,
Based on the cooling water temperature detected by the generated current detection means 14, the second
The electric water flow control valve 15 is controlled based on the relationship shown in FIG. 3 or 3, or an intermediate relationship between FIG. 2 and FIG. At this time, the blower 11 is stopped. Electric valve 15 for water flow control
If the cooling water temperature rises even when the opening degree of While keeping the temperature at maximum, this time blower 1 of outdoor heat exchanger 10
Controls the rotation speed of 1.

When such an operation is performed, the fluctuation of the cooling water temperature when the amount of heat generated by the battery stack 3 is large and the amount of waste heat recovered is as shown in Figure 5, and the fluctuation when the amount of waste heat recovered is small. The fluctuations in the cooling water temperature are shown in FIG. When the amount of heat generated in the battery stack 3 is large, the proportional band of the electric valve 15 for controlling the amount of water and the blower '11 of the heat exchanger for outdoor exhaust heat is narrowed to improve the response, so the amount of recovered exhaust heat can be reduced. The cooling water temperature can be stably controlled even in the event of sudden changes.

In addition, when the amount of heat generated by the battery stack 3 is small and the amount of waste heat recovered is large, the variation in the cooling water temperature is as shown in Figure 7, and the variation in the cooling water temperature when the amount of waste heat recovered is small is shown in Figure 7. The result is as shown in Figure 8. When the amount of heat generated in the battery stack 3 is small, the proportional band of the electric valve 15 for water flow control and the blower 11 of the outdoor heat exchanger 10 is widened to reduce the response. The opening degree of the electric water flow control valve 15 and the rotational speed of the blower 11 of the outdoor heat exchanger do not vary greatly in response to such fluctuations, and the cooling water temperature can be stably controlled.

Note that the electric water flow control valve 15 may be provided at the inlet portion of the exhaust heat recovery heat exchanger 7 of the battery cooling/exhaust heat recovery system piping 5.

FIG. 9 is a block diagram of a fuel cell according to a second embodiment of the present invention.

The fuel cell IB of this embodiment is a heat exchanger for exhaust heat recovery in the absorption chiller system piping 20 that returns from the exhaust heat recovery heat exchanger 7 to the exhaust heat recovery heat exchanger 7 through the absorption chiller 12. This embodiment is different from the fuel cell IA of the first embodiment in that an electric water flow control valve 15 capable of proportionally controlling the valve opening is provided at the outlet of the fuel cell 7.

The control details of the controller 18B are the same as in the first embodiment.

Note that the water flow control electric valve 15 may be provided in the artificial part of the exhaust heat recovery heat exchanger 7 of the absorption chiller system piping 20.

FIG. 10 is a block diagram of a fuel cell according to a third embodiment of the present invention.

In the fuel cell IC of this embodiment, instead of the water flow control electric valve 15 and the battery cooling/exhaust heat recovery circulation pump 26, a battery cooling circulation pump 21 with a constant rotation speed is provided in the battery cooling system piping 24. , which is provided in the exhaust heat recovery system piping 25 and includes an exhaust heat recovery circulation pump 22 whose rotation speed is controllable, and a rotation speed control means 23 for the exhaust heat recovery circulation pump 22, and the controller 18C is a cooling water temperature detection means. 13 and the generated current detection means 14, the exhaust heat recovery circulation pump 22
and the rotation speed of the blower 11 are proportionally controlled based on the cooling water temperature measured by the cooling water temperature detection means 13,
At that time, the proportional band of the proportional control is determined by the generated current detection means 1.
The difference from the fuel cells IA and IB of the first and second embodiments is that the width is narrowed when the generated current measured in step 4 is large, and widened when the generated current is small.

In this embodiment as well, the controller 18 is similar to the first embodiment.
C is based on the generated current detected by the generated current detection means 14, and is controlled by the control method shown in FIG. 2, or the control method shown in FIG. 3, or a control having a proportional band between FIGS. Choose a method. In other words, if the generated current is large, use the control method shown in Figure 2, if the generated current is small, use the control method shown in Figure 3, and if the generated current is between these, use the control method shown in Figures 2 and 3. Select a control method with an intermediate proportional band.

Regardless of whether you select the control method shown in Fig. 2 or 3, or which has a proportional band between Figs. 2 and 3,
Based on the cooling water temperature detected by the cooling water temperature detection means 13, the exhaust heat recovery circulation pump 22 is controlled based on the relationship shown in FIG. 2, FIG. 3, or an intermediate relationship between FIG. 2 and FIG. At this time, the blower 11 is stopped. If the cooling water temperature rises even if the rotation speed of the exhaust heat recovery circulation pump 22 is maximized, refer to Figure 2, Figure 3, or Figures 2 and 3.
Based on the relationship in the middle of the diagram, exhaust heat recovery circulation pump 2
This time, the rotation speed of the blower 11 of the outdoor exhaust heat heat exchanger 10 is controlled while keeping the rotation speed of the blower 11 of the outdoor exhaust heat heat exchanger 10 at the maximum.

When such an operation is performed, as in the first embodiment, when the amount of heat generated by the battery stack 3 is large and the amount of waste heat recovered is also large, the fluctuation in the cooling water temperature becomes as shown in FIG. ,
Fluctuations in the cooling water temperature when the amount of exhaust heat recovery is small are shown in FIG. When the amount of heat generated in the battery stack 3 is large, the proportion band of the exhaust heat recovery circulation pump 22 and the blower 11 of the outdoor exhaust heat heat exchanger 10 is narrowed to improve response, so the amount of exhaust heat recovery can be reduced. The cooling water temperature can be stably controlled even in the event of sudden changes in temperature.

In addition, when the amount of heat generated by the battery stack 3 is small and the amount of waste heat recovered is large, the fluctuation of the cooling water temperature is as shown in Fig. 7, and the fluctuation of the cooling water temperature when the amount of waste heat recovered is small. The result is as shown in FIG. When the amount of heat generated in the battery stack 3 is small, the proportional band of the exhaust heat recovery circulation pump 22 and the blower 11 of the outdoor exhaust heat heat exchanger 10 is widened to reduce the response. The rotational speed of the exhaust heat recovery circulation pump 22 and the rotational speed of the blower 11 of the outdoor exhaust heat heat exchanger 10 do not change significantly due to slight fluctuations, and the cooling water temperature can be stably controlled.

In this way, the cooling water temperature remains constant regardless of the amount of heat generated by the battery stack 3. Therefore, the battery will not deteriorate due to the cooling water temperature falling below the allowable lower limit or exceeding the allowable upper limit, and exhaust heat recovery can be performed stably.
There is no need to exhaust waste heat outdoors.

Furthermore, in this embodiment, when the amount of heat generated from the battery stack 3 is small, the rotation speed of the exhaust heat recovery pump 22 is reduced, so that the power required for controlling the cooling water temperature can be saved.

Furthermore, as shown in FIG. 4, when the fuel cell temperature, that is, the cooling water temperature is increased, the power generation efficiency increases. Figures 2 and 3
As shown in the figure, if the upper limit of the cooling water temperature of the proportional band of the blower 11 is set to the same value, when the amount of heat generated by the fuel cell is large, the proportional band is narrowed, so the amount of heat generated by the fuel cell is small. The cooling water temperature can be set higher than in other cases. Thereby, when the power generation output of the fuel cell is large, the power generation efficiency of the fuel cell can be improved.

〔Effect of the invention〕

As explained above, the present invention provides an electric valve for water flow control in the battery cooling/exhaust heat recovery system piping or the absorption chiller system piping, or a circulating pump for exhaust heat recovery in the exhaust heat recovery system piping. The rotation speed of the electric control valve or circulation pump for exhaust heat recovery and the rotation speed of the blower of the outdoor heat exchanger are controlled proportionally by the temperature of the battery cooling water, and the proportional band of the proportional control is controlled by the battery stack. By changing it based on the generated current, it is possible to stably control the cooling water temperature and make effective use of the fuel cell exhaust heat.

[Brief Description of the Drawings] Fig. 1 is a configuration diagram of a fuel cell according to a first embodiment of the present invention, and Fig. 2 is an example of setting the proportional band of the controller 18A when the amount of heat generated from the battery stack 3 is large. FIG. 3 is a diagram showing an example of setting the proportional band of the controller 18A when the amount of heat generated from the battery stack 3 is small. FIG. ID
Figure 5 shows the relationship between the power generation voltage, that is, the power generation efficiency.
8 to 8 are diagrams showing temporal fluctuations in battery cooling water temperature in this embodiment, and FIGS. A configuration diagram of a fuel cell according to the third embodiment, FIG. 11 is a configuration diagram of a conventional example of a fuel cell, and FIGS. 12, 13, 15, and 16 are battery cooling water temperature using conventional control methods. FIG. 14 is a diagram showing the relationship between the amount of heat generated in the battery stack 3 and the generated power. IA~ID--Fuel cell, 2-Reformer, 3-Battery stack, 4-Electric output section, 5-Battery cooling/exhaust heat recovery system piping, 6-Steam water separation 7...Heat exchanger for exhaust heat recovery, 8.9--Solenoid valve, 10--Heat exchanger for outdoor exhaust heat, 11--Blower, 12--Absorption refrigerator, 13--・Cooling water temperature detection means, 14--Generated current detection means, 15--Electric valve for water flow control, 16--Opening degree control means for electric valve 15 for water flow control, 17
-・Rotational speed control means for blower 11, 18A to 18D-
...controller, 19-wiring, 20-absorption chiller system piping, 21-battery cooling circulation pump, 22-exhaust heat recovery circulation pump, 23--rotation speed control means for exhaust heat recovery circulation pump 22 , 24-- Battery cooling system piping, 25-- Exhaust heat recovery system piping, 26-- Circulation pump for battery cooling and exhaust heat recovery, 31-- Heat generated in the battery stack 3 can be used as self-exhaust heat. Calorific value, patent applicant Nippon Telegraph and Telephone Corporation

Claims (1)

[Scope of Claims] 1. A reformer for producing hydrogen from fuel; a battery stack; a steam-water separator for separating water vapor from the cooling water of the battery stack; an electric output unit; and a heat generator for exhaust heat recovery. an exchanger; a heat exchanger for outdoor exhaust heat; cooling water temperature detection means provided in the steam/water separator; Provided at the inlet or outlet of the exhaust heat recovery heat exchanger in the battery cooling/exhaust heat recovery system piping that passes through the exhaust heat exchanger and returns to the battery stack, and is used to control the amount of water that allows proportional control of the valve opening degree. an electric valve; a blower for the outdoor exhaust heat heat exchanger whose rotational speed can be controlled proportionally; a generated current detection means provided in the electric output section; the cooling water temperature detection means and the generated current detection means. A signal is input from the means, and the opening degree of the electric water flow control valve and the rotation speed of the blower of the outdoor heat exchanger are proportionally adjusted based on the cooling water temperature measured by the cooling water temperature detecting means. and a controller that narrows the proportional band of the proportional control when the generated current measured by the generated current detection means is large, and widens it when the generated current is small. 2. A reformer that produces hydrogen from fuel, a battery stack, a steam separator that separates water vapor from the cooling water of the battery stack, an electric output section, a heat exchanger for exhaust heat recovery, and an outdoor exhaust system. a heat exchanger for heat; a cooling water temperature detection means provided in the steam-water separator; An electric water flow control valve that is installed at the inlet or outlet of the exhaust heat recovery heat exchanger in the refrigerator system piping and that can proportionally control the valve opening; and the outdoor exhaust heat valve that can proportionally control the rotation speed. a blower of a heat exchanger, a generated current detection means provided in the electric output section, a signal from the cooling water temperature detection means and the generated current detection means to determine the opening degree of the electric water flow control valve. The rotation speed of the blower of the outdoor heat exchanger is proportionally controlled based on the cooling water temperature measured by the cooling water temperature detection means, and at this time, the proportional band of the proportional control is set to A fuel cell comprising a controller that narrows the generated current measured by a current detection means when the generated current is large, and widens it when the generated current is small. 3. A reformer for producing hydrogen from fuel, a battery stack, a steam separator for separating water vapor from the cooling water of the battery stack, an electric output section, a heat exchanger for exhaust heat recovery, and an outdoor exhaust system. a heat exchanger for heat; cooling water temperature detection means provided in the steam water separator; An exhaust heat recovery circulation pump that is installed in the exhaust heat recovery system piping leading to the steam/water separator and whose rotation speed can be controlled proportionally; and a blower for the outdoor exhaust heat heat exchanger whose rotation speed can be controlled proportionally. A generated current detecting means provided in the electric output section; Signals are input from the cooling water temperature detecting means and the generated current detecting means to determine the rotational speed of the exhaust heat recovery circulation pump;
The rotation speed of the blower of the outdoor heat exchanger is proportionally controlled based on the cooling water temperature measured by the cooling water temperature detection means, and at this time, the proportional band of the proportional control is controlled by the generated current detection. and a controller that narrows the generated current when the generated current measured by the means is large and widens it when the generated current measured by the means is small.