JP2021174592A - Fuel cell system - Google Patents

Abstract

To show a user an indicator of proper hot water usage on the basis of the hot water temperature in a hot water storage tank.SOLUTION: A fuel cell system includes a hot water storage tank 14 that stores heated water using waste heat from a fuel cell module 22, a tank thermometer 15 that measures the hot water temperature of the hot water storage tank 14, and a display control unit that controls the heat storage status display on a heat storage display unit 66 of a remote control panel 46 on the basis of the tank hot water temperature and tap water temperature measured by the tank thermometer 15.SELECTED DRAWING: Figure 1

Description

The present invention relates to a fuel cell system, and more particularly to a cogeneration fuel cell system that supplies thermal energy along with electrical energy.

Conventionally, in a fuel cell system, a cogeneration system has been proposed in which power is generated by a fuel cell, water is heated by waste heat from the fuel cell, and heat is stored in a hot water storage tank. The amount of hot water stored in the hot water storage tank changes above a predetermined temperature depending on the amount of hot water used and the state of power generation.

For example, Patent Document 1 discloses a display unit that displays a level corresponding to an operation with a temperature control switch. However, there is no indication according to the temperature of the hot water in the tank. Users are required to provide indicators of the proper use of hot water.

Patent No. 6502562

The present invention has been made in consideration of the above facts, and an object of the present invention is to show the user an index of appropriate use of hot water based on the hot water temperature of the hot water storage tank.

The fuel cell system according to claim 1 of the present invention includes a fuel cell module that generates power using gas fuel, a hot water storage tank that stores heated water by utilizing exhaust heat from the fuel cell module, and the hot water storage. It includes a thermometer that measures the hot water temperature of the tank, and a display control unit that controls the heat storage status display on the heat storage display unit based on the hot water temperature and the temperature of clean water measured by the thermometer. ..

According to the fuel cell system according to claim 1, the heat storage state is displayed on the heat storage display unit based on the temperature of the hot water in the hot water storage tank and the temperature of the clean water. Therefore, it is possible to show the user an appropriate hot water usage index based on not only the hot water temperature of the hot water storage tank but also the clean water and the hot water temperature of the hot water storage tank.

In the fuel cell system according to claim 2 of the present invention, the display control unit defines a temperature higher than the tap water temperature by ΔT ° C as the first reference temperature and a temperature higher than the first reference temperature as the second reference temperature. Then, three heat storage state displays are divided into a low temperature display lower than the first reference temperature, a medium temperature display above the first reference temperature and below the second reference temperature, and a high temperature display higher than the second reference temperature. Separately, it is displayed on the heat storage display unit.

According to the fuel cell system according to claim 2, the heat storage display unit distinguishes between a low temperature display, a medium temperature display, and a high temperature display. The low temperature display corresponds to a temperature lower than the first reference temperature, which is ΔT ° C higher than the clean water temperature. The medium temperature display is a display corresponding to a temperature equal to or higher than the first reference temperature and lower than the second reference temperature higher than the first reference temperature. The high temperature display is a display of a temperature higher than the second reference temperature.

By distinguishing the temperature display in this way, it is possible to show the user an appropriate hot water usage index in an easy-to-understand manner.

In the fuel cell system according to claim 3 of the present invention, the ΔT ° C. is in the range of 0 ° C. to 60 ° C.

By setting the first reference temperature within the range of ΔT ° C higher than the clean water temperature, when the heat storage display is displaying a low temperature, the amount of heat storage is small and it is not suitable for using hot water. Can be shown to be.

In the fuel cell system according to claim 4 of the present invention, the second reference temperature is in the range of 32 ° C. to 75 ° C.

By setting the second reference temperature within such a range, when a high temperature display is performed on the heat storage display unit, it is proposed that the amount of heat storage is large and hot water is actively used. It can be shown that there is.

The fuel cell system according to claim 5 of the present invention is characterized in that the heat storage display unit displays the heat storage state by different colors of the same display portion.

According to the fuel cell system according to claim 5, it is possible to display the heat storage state in an easy-to-understand manner by using different colors.

According to the present invention, it is possible to indicate to the user an index regarding the proper use of hot water based on the hot water temperature of the hot water storage tank.

It is the schematic of the fuel cell system which concerns on this embodiment. It is a block diagram which shows the structure of the controller which concerns on this embodiment. It is a front view of the operation remote controller which concerns on this embodiment. It is a flowchart of the heat storage state display processing which concerns on this embodiment.

Hereinafter, an example of a mode for carrying out the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a schematic view of the fuel cell system 10 according to the present embodiment.

The fuel cell system 10 includes a fuel cell unit 12. A hot water storage tank 14 is attached to the fuel cell unit 12, and the fuel cell system 10 is a so-called cogeneration system.

In the present embodiment, the fuel cell unit 12 is provided with the hot water storage tank 14 as an example, but the fuel cell unit 12 and the hot water storage tank 14 may be separate units.

The fuel cell unit 12 includes a controller 16, a desulfurizer 20, a fuel cell (FC) module 22, an inverter 28, a heat exchanger 30, and a hot water storage tank 14.

The desulfurizer 20 removes sulfur and sulfur compounds contained in the gas supplied from the gas supply pipe 18 (for example, city gas 13A).

The fuel cell module 22 has a reforming unit and a power generation unit inside. In the reforming section, the gas that has passed through the desulfurizer 20 is reformed into a gas containing hydrogen as a main component. The power generation section uses hydrogen to generate electricity. The electric power from the power generation unit of the fuel cell module 22 is converted into alternating current by the inverter 28, and then consumed by the electric power load of the household appliances 24 (household electrical appliances), the lighting 26, and the like in the house 48.

Hot water is stored in the hot water storage tank 14. The hot water is heated by heat exchange between the high temperature exhaust gas discharged from the fuel cell module 22 and the heat exchanger 30. The hot water in the hot water storage tank 14 is used for hot water supply to the hot water supply equipment 49 (shower, bath, sink, etc.) inside the house 48 by directly or indirectly exchanging heat, and heat in floor heating, air conditioning equipment, etc. Used as a replacement. By using the hot water stored in the hot water storage tank 14 in this way, the heat generated by power generation can be used. , Energy saving.

(Configuration of controller 16)

As shown in FIG. 2, the controller 16 includes a CPU 34, a RAM 36, a ROM 38, a storage 35, an I / O 40, and a bus such as a data bus or a control bus connecting them. The ROM 38 stores data such as a heat storage status display processing program, a first reference temperature T1, and a second reference temperature T2, which will be described later.

The controlled device 12D of the fuel cell unit 12 is connected to the I / O 40. By the control of the controller 16, each operation of the controlled device 12D is controlled. Further, a remote controller panel 46, a tank thermometer 15, and a clean water thermometer 17 are connected to the I / O 40.

The remote control panel 46 is installed inside the target house 48 (see FIG. 1) in which the fuel cell system 10 is installed, and has a function for the user to input a command regarding the fuel cell system 10 and the fuel cell system 10. It has a function to display the status. On the remote control panel 46, the heat storage state in the hot water storage tank 14 is displayed on the heat storage display unit 66 (see FIG. 3).

The tank thermometer 15 is provided in the hot water storage tank 14 and measures the temperature of the upper side of the hot water stored in the hot water storage tank 14. The temperature measured by the tank thermometer 15 is defined as the tank hot water temperature W1. The clean water thermometer 17 measures the temperature of clean water. The clean water here may be clean water that is directly supplied to the hot water storage tank 14, or may be clean water that is heated by heat exchange with the hot water in the hot water storage tank 14. The clean water thermometer 17 may be provided in a pipe that directly supplies clean water to the hot water storage tank 14, as long as it can measure the temperature of the clean water heated by the hot water in the hot water storage tank 14. It may be provided at a place where the temperature of clean water supplied to (for example, a backup water heater) can be measured. The temperature measured by the clean water thermometer 17 is defined as the clean water temperature W2.

As shown in FIG. 1, a microcomputer meter 50 is attached to the gas supply pipe 18. A branch portion B1 is provided on the downstream side of the microcomputer meter 50, one branch pipe 18A supplies gas to the fuel cell unit 12, and the other branch pipe 18B is a gas appliance (conro 52, gas) in the house 48. Gas is supplied to the fan heater 54, etc.).

The microcomputer meter 50 measures the flow rate of the supplied gas and has a plurality of functions (abnormal outflow monitoring function, seismic sensitivity function, pressure monitoring function, long-term use monitoring function, minute leakage monitoring function) for monitoring an abnormality in the gas supply. Etc.).

Here, the first reference temperature T1, the second reference temperature T2, and the heat storage state will be described. The first reference temperature T1 is a temperature ΔT ° C. higher than the clean water temperature W2. ΔT ° C. is set so that the amount of heat obtained by preheating the clean water is comparable to the cost required for the preheating (power consumption of the auxiliary machine) or the energy required for the preheating. The ΔT ° C. is preferably in the range of 0 ° C. to 60 ° C.

Further, the second reference temperature T2 is a temperature higher than the first reference temperature T1 and is the minimum temperature for discharging the hot water supply set temperature. The second reference temperature T2 is preferably in the range of 32 ° C. to 75 ° C. The first reference temperature T1 and the second reference temperature T2 are used for determination in the heat storage status display process described later.

The heat storage state of the hot water storage tank is displayed on the heat storage display unit 66 of the remote control panel 46, and the tank hot water temperature W1 measured by the tank thermometer 15 is a low temperature display L lower than the first reference temperature T1 and the first reference temperature T1. As described above, the medium temperature display M lower than the second reference temperature T2 and the high temperature display H higher than the second reference temperature T2 are displayed separately. In the present embodiment, as an example, the low temperature display L is displayed in blue, the medium temperature display M is displayed in yellow, and the high temperature display H is displayed in red. The three different heat storage states may be displayed in a manner other than color. For example, the alphabet "L, M, H" may be used for distinction, or "low, medium, high" may be used for distinction.

FIG. 3 is a front view of the remote control panel 46 according to the present embodiment.

As shown in FIG. 3, the remote control panel 46 has a rectangular appearance, and a touch panel unit 64 is arranged above the main panel 56.

The touch panel unit 64 displays the time, operating status, set numerical values, etc., and a touch pad unit is laid so as to overlap a part or all of the display surface, so that the user's touch operation can be recognized. It has become like. In FIG. 3, the display of the main panel 56 is an example of the operation status screen, and the main panel 56 can be switched to various different screens by touching the "screen switching" which is the touch pad unit.

Further, the main panel 56 below the touch panel unit 64 is an arrangement area 68 for a plurality of operation switch groups. The operation switch group is a so-called hard switch, and operation switches related to hot water supply and power generation are arranged.

In the remote controller panel 46 shown in FIG. 3, the arrangement position, number, function, shape, etc. of the touch panel unit 64 and the operation switch group may be changed depending on the model, year, version, etc., and the remote controller of FIG. The shape of the panel 46 is not limited to that of the panel 46.

Next, the heat storage state display process in the fuel cell system 10 of the present embodiment will be described. The heat storage state display process is continuously performed based on the flow shown in FIG. 4 during the operation of the fuel cell system 10.

First, in step S12, the blue color of the low temperature display L is displayed on the heat storage display unit 66, and in step S14, the tank hot water temperature W1 is acquired to determine whether or not the tank hot water temperature W1 is lower than the first reference temperature T1. .. If the determination is affirmed, the process returns to step S12, and the low temperature display L is continued. When the determination is denied, that is, when the acquired tank hot water temperature W1 is equal to or higher than the first reference temperature T1, the yellow color of the medium temperature display M is displayed on the heat storage display unit 66 in step S16.

Next, in step S18, the tank hot water temperature W1 is acquired, and it is determined whether or not the tank hot water temperature W1 is lower than the first reference temperature T1-T0 ° C. The T0 ° C. here is set to about 2 ° C. to 3 ° C. As a result, the heat storage display is maintained and stable display can be performed even if the clean water temperature or the tank hot water temperature W1 fluctuates by about 2 ° C. to 3 ° C. or the temperature drops.

If the determination in step S18 is affirmed, the process returns to step S12 and the low temperature display L is performed.

If the determination in step S18 is denied, the tank hot water temperature W1 is acquired in step S20 to determine whether the tank hot water temperature W1 is lower than the second reference temperature T2. If the determination is affirmed, the process returns to step S16 and the medium temperature display M is continued. When the determination is denied, that is, when the acquired tank hot water temperature W1 is equal to or higher than the second reference temperature T2, the red color of the high temperature display H is displayed on the heat storage display unit 66 in step S22.

Next, in step S24, the tank hot water temperature W1 is acquired, and it is determined whether or not the tank hot water temperature W1 is lower than the second reference temperature T2-T0 ° C. If the determination is affirmed, the process returns to step S16 and the medium temperature display M is performed. If the determination is denied, the process returns to step S22 and the high temperature display H is continued.

In the fuel cell system 10 of the present embodiment, the heat storage display is performed based not only on the tank hot water temperature W1 but also on the temperature including the clean water temperature W2 (first reference temperature T1), so that a more appropriate hot water usage index is displayed. Can be shown to the user. For example, the user is recommended to actively use hot water when the red color of the high temperature display H is displayed on the heat storage display unit 66. Further, when the yellow color of the medium temperature display M is displayed on the heat storage display unit 66, it is possible to use hot water while saving energy, but it is recommended to refrain from using a large amount of hot water such as filling the bath. NS. Further, when the blue color of the low temperature display L is displayed on the heat storage display unit 66, it is recommended that the hot water be used after a while.

In general, whether the backup heat source machine heats the clean water independently at the time of hot water supply (A) or whether the clean water is preheated with the hot water in the hot water storage tank 14 and then heated by the backup heat source machine (B). Control is done. In this case, when switching the control of (A) and (B) according to the temperature difference between the tank hot water temperature W1 and the clean water temperature W2, the temperature difference is set to ΔT ° C. to set the first reference temperature. It can be linked with T1.

Further, by displaying on the heat storage display unit 66 using different colors, it is possible to display the heat storage state in an easy-to-understand manner.

In the present embodiment, the heat storage state is displayed by distinguishing it into three types, but it may be displayed by distinguishing two types or by distinguishing four or more types.

10 Fuel cell system 14 Hot water storage tank 16 Controller 22 Fuel cell module W1 Tank hot water temperature W2 Top water temperature T1 First reference temperature T2 Second reference temperature L Low temperature display M Medium temperature display H High temperature display

Claims (5)

A fuel cell module that uses gas fuel to generate electricity,
A hot water storage tank that stores heated water using the waste heat from the fuel cell module,
A thermometer that measures the temperature of the hot water in the hot water storage tank,
A display control unit that controls the heat storage status display on the heat storage display unit based on the hot water temperature and the clean water temperature measured by the thermometer.
A fuel cell system equipped with. When the display control unit sets a temperature higher than the tap water temperature by ΔT ° C as the first reference temperature and a temperature higher than the first reference temperature as the second reference temperature, the display control unit displays a low temperature lower than the first reference temperature. The first aspect of claim 1, wherein three heat storage state displays, a medium temperature display above the first reference temperature and below the second reference temperature, and a high temperature display higher than the second reference temperature, are displayed separately on the heat storage display unit. Of the fuel cell system. The fuel cell system according to claim 2, wherein ΔT ° C is in the range of 0 ° C to 60 ° C. The fuel cell system according to claim 2 or 3, wherein the second reference temperature is in the range of 32 ° C. to 75 ° C. The fuel cell system according to any one of claims 1 to 4, wherein the heat storage display unit displays the heat storage state by different colors of the same display portion.

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