JP7101758B2 - Fuel cell device, control device and control program - Google Patents

Description

The present disclosure relates to fuel cell devices, controls and control programs.

A fuel cell module having a cell stack in which a plurality of fuel cell cells capable of obtaining electric power by using a fuel gas which is a hydrogen-containing gas and air which is an oxygen-containing gas is laminated in a storage container is known. Further, various fuel cell devices in which the fuel cell module and auxiliary equipment necessary for its operation are housed in a housing such as an outer case have been proposed.

In such a fuel cell device, excess fuel gas that has not been used for power generation is burned, and the exhaust gas after combustion is passed through a heat exchanger or the like to be cooled. At the time of this heat exchange, the condensed water generated by condensing the water vapor contained in the exhaust gas is purified by an ion exchange resin or the like and stored in a water tank such as a reformed water tank. Then, so-called water self-sustaining operation is performed in which the stored water is supplied as reformed water to a reformer that reforms raw fuel such as natural gas by steam reforming.

Regarding the operation and control of the fuel cell using the reformed water, Patent Document 1 states that when the amount of the reformed water stored in the water tank is insufficient due to, for example, a high outside temperature, the fuel cell It is disclosed that the amount of reaction air supplied per unit time supplied to the cathode is reduced to increase the air utilization rate of the fuel cell. A fuel cell system is described in which the amount of condensed water recovered, which becomes reformed water, is increased to recover the amount of stored water.

Further, Patent Document 2 describes, in a fuel cell apparatus including a condensing portion that generates condensed water by heat exchange with low-temperature water as a heat medium or a refrigerant, according to the amount of reformed water stored in a water tank. A fuel cell device that suppresses a shortage of the amount of reformed water stored in a water tank by controlling the amount of heat medium supplied to the heat exchanger is disclosed.

Japanese Unexamined Patent Publication No. 2008-234869 Japanese Unexamined Patent Publication No. 2012-119086

The fuel cell apparatus of the present disclosure includes a fuel cell, a first tank for storing water recovered from exhaust gas discharged from the fuel cell for supplying to the fuel cell, and the height of the water surface in the first tank. A water level detecting device for detecting the above, a control device for controlling the operation of the fuel cell and each auxiliary device attached to the fuel cell, and a water replenishing device for supplying water to the first tank from the outside are provided.
The control device is
When the water level in the first tank becomes equal to or lower than the predetermined first predetermined water level,
The first control that controls the operation of each auxiliary device so that the amount of water recovered from the exhaust gas increases, and the amount of water supplied from the first tank to the fuel cell decreases. Of the second control that controls the operation of each of the auxiliary machines, the water recovery operation control that controls at least one of them is executed.
In the control device, after a predetermined first predetermined time has elapsed from the start of the water recovery operation control, the water level in the first tank measured by the water level detection device is equal to or lower than the first predetermined water level. If this is the case, the water replenishment device executes refilling control for replenishing the first tank with a predetermined amount of external water.

Further, the control device of the present disclosure is a control device for controlling a fuel cell device including a fuel cell.
The first control that controls the operation of each auxiliary machine attached to the fuel cell so that the amount of water recovered from the exhaust gas discharged from the fuel cell increases, and the water recovered from the exhaust gas discharged from the fuel cell. A second control for controlling the operation of each auxiliary machine attached to the fuel cell so that the amount of water supplied to the fuel cell from the first tank stored for supplying the fuel to the fuel cell is reduced, and the above-mentioned It is possible to carry out replenishment control for replenishing a predetermined amount of external water to the first tank by a water replenishing device for replenishing the first tank from the outside.
The control device controls at least one of the first control and the second control when the water level in the first tank becomes equal to or lower than a predetermined first predetermined water level. To execute. After the water recovery operation control is executed and continued for a predetermined first predetermined time, when the water level in the first tank is equal to or lower than the first predetermined water level, the water replenishment control is executed.

Further, the control program of the present disclosure applies to a control device for controlling a fuel cell device including a fuel cell.
When the water level in the first tank stored for supplying the water recovered from the exhaust gas discharged from the fuel cell to the fuel cell becomes equal to or lower than the predetermined first predetermined water level, the water is recovered from the exhaust gas. A first water recovery operation control step for performing a first control for controlling the operation of each auxiliary machine attached to the fuel cell so that the amount of water increases, and
Each attached to the fuel cell so that the amount of water supplied from the first tank to the fuel cell decreases when the water level in the first tank becomes equal to or lower than a predetermined first predetermined water level. A second water recovery operation control step for performing a second control for controlling the operation of the auxiliary machine, and
After at least one of the first water recovery operation control step and the second water recovery operation control step continues for a predetermined first predetermined time, the water level in the first tank becomes the first predetermined water level. In the following cases, the water replenishment device for replenishing the first tank with water from the outside executes the refilling control step of replenishing the first tank with a predetermined amount of external water.

On the other hand, the fuel cell apparatus of the present disclosure includes a fuel cell, a first tank for storing water recovered from exhaust gas discharged from the fuel cell for supplying to the fuel cell, and a water surface in the first tank. A water level detecting device for detecting the height and a control device for controlling the operation of the fuel cell and each auxiliary machine attached to the fuel cell are provided.
The control device operates each of the auxiliary machines so that the amount of water recovered from the exhaust gas increases when the water level in the first tank becomes equal to or lower than a predetermined second predetermined water level. At least one of the first control to be controlled and the second control to control the operation of each auxiliary machine so that the amount of water supplied from the first tank to the fuel cell is reduced is performed. Execute water recovery operation control.
In the control device, after a predetermined third predetermined time has elapsed from the start of the water recovery operation control, the water level in the first tank measured by the water level detection device is equal to or lower than the second predetermined water level. If so, control is performed to stop the power generation operation of the fuel cell device.

Further, the control device of the present disclosure corresponding to the above-mentioned fuel cell device is a control device for controlling a fuel cell device including a fuel cell.
The first control that controls the operation of each auxiliary machine attached to the fuel cell so that the amount of water recovered from the exhaust gas discharged from the fuel cell increases, and the water recovered from the exhaust gas discharged from the fuel cell. A second control that controls the operation of each auxiliary machine attached to the fuel cell so that the amount of water supplied to the fuel cell from the first tank stored for supplying the fuel cell to the fuel cell is reduced. It is feasible.
The control device controls at least one of the first control and the second control when the water level in the first tank becomes equal to or lower than a predetermined second predetermined water level. When the water level in the first tank is equal to or lower than the second predetermined water level after the water recovery operation control is executed and the water recovery operation control is continued for a predetermined third predetermined time, the power generation operation of the fuel cell device is performed. Execute control to stop.

Further, the control program of the present disclosure corresponding to the above-mentioned fuel cell device is a control device for controlling a fuel cell device including a fuel cell.
When the water level in the first tank stored for supplying the water recovered from the exhaust gas discharged from the fuel cell to the fuel cell becomes equal to or lower than the predetermined second predetermined water level, the water is recovered from the exhaust gas. A first water recovery operation control step for performing a first control for controlling the operation of each auxiliary machine attached to the fuel cell so that the amount of water increases, and
Each attached to the fuel cell so that the amount of water supplied from the first tank to the fuel cell decreases when the water level in the first tank becomes equal to or lower than a predetermined second predetermined water level. A second water recovery operation control step for performing a second control for controlling the operation of the auxiliary machine, and
After at least one of the first water recovery operation control step and the second water recovery operation control step continues for a predetermined third predetermined time, the water level in the first tank becomes the second predetermined water level. In the following cases, the power generation operation stop step of stopping the power generation operation of the fuel cell device is executed.

The purposes, features, and advantages of this disclosure will become clearer from the detailed description and drawings below.
It is a schematic block diagram of the fuel cell apparatus of embodiment. It is explanatory drawing around the reforming water tank of the fuel cell apparatus which enlarged the F part of FIG. It is an external perspective view of a fuel cell device. It is a flowchart of water recovery operation control and water replenishment control in the fuel cell apparatus of 1st Embodiment. It is an example of the flowchart of the operation restart control in the fuel cell apparatus of 1st Embodiment, and is the figure which shows the flow of the 1st operation restart control. It is another example of the flowchart of the operation resumption control in the fuel cell apparatus of 1st Embodiment, and is the figure which shows the flow of the 2nd operation resumption control. It is a flowchart of water recovery operation control in the fuel cell apparatus of 2nd Embodiment. It is an example of the flowchart of the operation restart control in the fuel cell apparatus of 2nd Embodiment, and is the figure which shows the flow of the 1st operation restart control. It is an example of the flowchart of the operation restart control in the fuel cell apparatus of 2nd Embodiment, and is the figure which shows the flow of the 2nd operation restart control. It is another example of the flowchart of the operation restart control in the fuel cell apparatus of 2nd Embodiment, and is the figure which shows the flow of a heat medium cooling control and a start preparation control.

Hereinafter, the fuel cell apparatus of the embodiment will be described with reference to the drawings.
1, FIG. 2 and FIG. 3 are diagrams illustrating a schematic configuration of a fuel cell device according to an embodiment. Note that FIG. 2 is a schematic configuration around the reforming water tank, which is an enlarged view of the F portion of FIG.

In the fuel cell apparatus 100 of the embodiment, power is supplied by operating a fuel cell module 1 that generates power by using raw fuel such as natural gas and LP gas, and heat exchanger 3, radiator 4, and heat medium circulation. Hot water is supplied using an exhaust heat recovery system (also referred to as heat cycle HS) including a pump P2 and a heat storage tank 5. The heat storage tank 5 described above corresponds to the second tank of the present disclosure. It is also possible to use a so-called monogeneration system that does not supply hot water.

Further, the fuel cell device 100 includes a reforming water tank 6, a power conditioner 20, a control device 30, a storage device 40 and the like as auxiliary devices in addition to the fuel cell module 1 and the like described above. Further, the fuel cell device 100 includes a reforming water flow path R including a reforming water pump P1, a drainage flow path D, and various sensors. The sensors include a water level detector WL ₁ , a water detector located at a medium water level, a water detector WL ₂ located at a low water level, a water temperature gauge TS ₁ which is a heat medium temperature measuring device, and reformed water. It is provided with at least an electric conductivity meter WC ₁ or the like, which is a water quality measuring device for measuring water quality.

The fuel cell module 1 is housed in a storage container 10. A cell stack 11 in which a plurality of fuel cell cells are stacked, a reformer 12 that reforms the raw fuel with steam using steam, and an ignition heater for igniting excess fuel gas (not shown). , And an exhaust gas catalyst or the like filled in the catalyst container 2. Then, as shown in FIG. 3, the fuel cell module 1 is arranged in a case 50 including each frame 51 and an exterior panel (not shown).

Although not shown in FIG. 3, in the case 50, a gas pump B1 for supplying raw fuel such as natural gas to the reformer and an oxygen-containing gas such as air as shown in FIG. 1 are cells. The air blower B2 to be supplied to the stack, the reforming water pump P1 for supplying the reforming water in the reforming water tank 6 to the reformer 12 as raw water for steam reforming, and the surplus in the reforming water tank 6. A drainage channel D or the like for draining water is arranged.

Further, in the case 50, as described above, the power conditioner 20 linked to the system power supply, the control device 30 including the control board for controlling the entire device, the storage device 40, and the like, and the operation of the fuel cell are controlled. Various sensors used for this are also arranged.

In the fuel cell apparatus 100 having the above-described configuration, the exhaust gas discharged from the fuel cell module 1 and the water flowing in the heat exchanger 3 are the heat exchangers 3 arranged adjacent to the fuel cell module 1. Heat is exchanged with the heat medium or fuel of the above, and the moisture contained in the exhaust gas condenses to generate condensed water.

The generated condensed water is separated by a gas-liquid separator or the like, and is introduced into the reforming water tank 6 that collects and stores the condensed water via the condensed water flow path C. The reforming water tank 6 corresponds to the first tank of the present disclosure.

The exhaust gas from which the water has been removed is exhausted to the outside of the fuel cell device via the exhaust gas flow path E. Further, the reformed water stored in the reformed water tank 6 is supplied to the reformer 12 in the fuel cell module 1 via the reformed water flow path R and the reformed water pump P1, and the reformed water is used. It is used for steam reforming of raw materials and fuels.

FIG. 2 is an enlarged view of the portion related to the power generation operation of the fuel cell and the reformed water used for the fuel cell in the configuration of the fuel cell device 100, that is, the inside of the two-dot chain line F in FIG.

The reformed water tank 6 for purifying and storing condensed water is composed of a first reformed water tank 61 for purification treatment and a second reformed water tank 62 for storage. The first reforming water tank 61 and the second reforming water tank 62 are connected by a lower water pipe 65 and communicate with each other.

A reforming water outlet 62a connected to a suction port of the reforming water pump P1 is provided at the lower part or the bottom of the second reforming water tank 62 for storing the generated reforming water. Further, on the upper side surface of the second reforming water tank 62, a surplus water outlet 62b connected to the drainage flow path D is provided.

At the lower part of the second reforming water tank 62, a water detector WL ₂ for detecting that the water level, which is the water level of the stored reforming water, has reached the drought level, which is the lower limit water level, is arranged. .. The black circles of each sensor in the figure indicate the position where the sensor is arranged or the position where the tip of the probe or the like is detected.

The first reformed water tank 61 for collecting and purifying the condensed water to produce the reformed water is filled with an ion exchange resin for purifying the condensed water recovered from the heat exchanger 3. The ion exchange resin container 63 of No. 1 and a second ion exchange resin container filled with an ion exchange resin for purifying tap water or the like (hereinafter referred to as external water) replenished from the outside when the reforming water is insufficient. 64 and are arranged.

A water detector WL that detects that the water level, which is the water level of the stored reformed water, has reached the medium water level, which is a predetermined set water level, at a predetermined intermediate position of the first reformed water tank 61. ₁ is arranged. As shown in FIG. 2, a second electric conductivity meter WC ₂ for measuring the conductivity (unit: μS / cm) of the reformed water, which is the stored water, is arranged in the first reforming water tank 61. It may be set.

In the fuel cell device 100 of the present embodiment, as a water supply device for supplying water to the water tank from the outside, as shown in FIG. 2, the reformed water tank 6 and the water supply (Waterworks) which is an external water source are used. _A water supply flow path G including an electromagnetic opening / closing type water stop valve V1 is provided between the water supply flow path G and the like.

The end portion of the water supply flow path G on the downstream side is connected to an external water receiving port 61a provided in the lower part of the first reforming water tank 61. The external water flowing in from the external water receiving port 61a is first from the external water introduction port 64a provided at the bottom of the second ion exchange resin container 64 via the extension pipe 61b arranged inside the tank. It is introduced into the reforming water tank 61.

Further, the second ion exchange resin container 64 is filled with an ion exchange resin for purifying external water. While the external water passes through the ion exchange resin layer, impurities contained in tap water and the like are removed, and deionized water having a conductivity of about 1 μS / cm, that is, refilled water for reforming water is purified. ing.

The electric conductivity meter WC ₁ in the figure is an example of a breakthrough determination device that determines whether or not the above-mentioned ion exchange resin has broken through. The electric conductivity meter WC ₁ is arranged on the upper part of the second ion exchange resin container 64 in which the replenishment water stays so that the conductivity of the replenishment water which is the deionized water after the purification treatment can be measured. There is.

The purified water flows out from the purified water outlet 64b provided on the upper side surface of the second ion exchange resin container 64, flows down to the water storage portion in the first reformed water tank 61, and is reformed water. Is stored as.

In the fuel cell device 100 of the present embodiment, when the reforming water in the reforming water tank 6 is insufficient, the external water such as the above-mentioned tap water is purified via an ion exchange resin or the like and then used as supplementary water. It is introduced into the reforming water tank 6. The conditions and controls for refilling water will be described later.

The fuel cell device 100 then includes a control device 30 that includes at least one processor to provide control and processing power to perform various functions, as described in detail below.

According to various embodiments, the at least one processor may be run as a single integrated circuit or as multiple communicable integrated and / or discrete circuits. At least one processor can be run according to a variety of known techniques.

In one embodiment, the processor comprises, for example, one or more circuits or units configured to perform one or more data calculation procedures or processes by performing instructions stored in the associated memory. In other embodiments, the processor may be firmware configured to perform one or more data calculation procedures or processes, such as a discrete logic component.

According to various embodiments, the processor is one or more processors, controllers, microprocessors, microcontrollers, application-specific integrated circuits, digital signal processors, programmable logic devices, field programmable gate arrays, or devices thereof or Any combination of configurations, or other known device and configuration combinations, may be included to perform the functions described below.

The control device 30 includes a storage device 40, a power conditioner 20, a fuel cell module 1, a raw fuel supply device such as a gas pump B1, an oxygen-containing gas supply device such as an air blower B2, a reformed water pump P1 and the like. Water supply device, water supply device such as water supply flow path G including water stop valve V ₁ , water level detector such as medium water level water detector WL ₁ , low water level water detector WL ₂ , water temperature gauge It is connected to various sensors such as a heat medium temperature measuring device such as TS ₁ and a water quality measuring device such as an electric conductivity meter WC ₁ , and controls and manages the entire fuel cell device 100 including each of these functional units. The control device 30 acquires a program stored in the storage device 40 and executes this program to realize various functions related to each part of the fuel cell device 100.

When a control signal or various information is transmitted from the control device 30 to another functional unit or device, the control device 30 and the other functional unit may be connected by wire or wirelessly. The control characteristic of the present embodiment performed by the control device 30 will be described later. In the present embodiment, the control device 30 particularly controls the replenishment of the above-mentioned external water to the reformed water storage unit. Further, in each figure, the illustration of the connection line connecting the control device 30 and the storage device 40 with each device constituting the fuel cell and each sensor may be omitted.

The storage device 40 can store programs and data. The storage device 40 may also be used as a work area for temporarily storing the processing result. The storage device 40 includes a recording medium. The recording medium may include any non-transitory storage medium such as a semiconductor storage medium and a magnetic storage medium. Further, the storage device 40 may include a plurality of types of storage media. The storage device 40 may include a combination of a portable storage medium such as a memory card, an optical disk, or a magneto-optical disk, and a storage reading device. The storage device 40 may include a storage device used as a temporary storage area such as a RAM (Random Access Memory).

Next, the water recovery operation control for recovering the amount of reformed water and the water replenishment control when the reformed water is insufficient are performed by the fuel cell device having the above configuration as follows. The following description will be given based on the flowcharts of FIG. 4 and FIGS. 5A and 5B. Further, each step in the flowchart is abbreviated as "S" and is referred to. For example, step 1, step 2 ... Are referred to as [S1], [S2] ..., respectively. The same notation is used in the figure.

The control device 30 in the fuel cell device of the first embodiment shown in FIGS. 4 and 5A and 5B is a reforming water tank 6 which is a first tank during normal or normal times when no abnormality is detected in the system. Until the water detection signal transmitted by the water detector WL ₁ arranged at the predetermined intermediate position is interrupted, that is, the water detection signal from the medium water level water detector WL ₁ which is the first predetermined water level can be received. Until it disappears, the loop of [S1] for determining whether or not the water detection signal is received, that is, the left side of the figure in [S1] of the flowchart of FIG. 4 is repeated while waiting.

Here, when the water detection signal transmitted by the water detector WL ₁ at the middle water level is no longer received during the loop of the above [S1], the control device 30 starts the following water recovery operation control [S2]. ..

The water recovery operation control is performed for the purpose of recovering the amount of reformed water in the reformed water tank 6. In the control, after [S2], the power generation output of the fuel cell is suppressed, and other accessories are also controlled to continue the power generation operation of the fuel cell.

Specifically, at least one of a first control that increases the amount of water recovered from the exhaust gas and a second control that reduces the amount of water supplied from the reforming water tank 6 to the fuel cell module 1. To control.

In the first control, in addition to suppressing the power generation output of the fuel cell as described above, for example, the water flow rate, which is the transmission amount of the heat cycle HS system heat medium circulation pump P2, is maximized at the rated value, and the fan of the radiator 4 is used. Controls to raise the operating duty ratio of the pump and fan of the heat medium circulation system, such as raising the rotation of the radiator to the rated maximum rotation speed.

Further, in order to lower the fuel utilization rate and increase the oxygen utilization rate, the gas flow rate, which is the delivery amount of the gas pump B1 that feeds the raw fuel to the reformer, and the delivery of the air blower B2 that feeds the air to the cell stack. Control is performed to increase the operating duty ratio of the pump and blower of the raw material supply system, such as controlling the amount of air flow rate. This makes it possible to recover the condensed water with maximum efficiency.

The second control is, for example, a control for reducing as much as possible the amount of water supplied, which is the amount of reformed water sent out, by the reforming water pump P1 which is a device for supplying water to the fuel cell module 1.

Then, in the water recovery operation control described in [S2] and thereafter, at least one of these first control and the second control is controlled at the same time if possible, so that the condensed water can be condensed water with maximum efficiency. Can be recovered.

While the water recovery operation control is being continued, the control device 30 confirms whether or not the water detector WL ₂ at the low water level position, which is the drought position of the reforming water tank 6, is transmitting the water detection signal [S3]. .. If the water detection signal from the water detector WL ₂ at the low water level position is interrupted in [S3], it is determined that the amount of reformed water stored in the reforming water tank 6 has dropped to a dangerous level. Then, the control shifts to the control to stop the power generation operation (see the drought alert in [S12]). When the drought alert is issued and the power generation operation is stopped [S12], the operation can be restarted by performing maintenance by human hands.

Next, the control device 30 confirms the degree of recovery of the water level of the stored reforming water in [S4]. That is, at this time, if the control device 30 receives the water detection signal from the water detector WL ₁ and confirms that the water level of the stored reforming water has recovered to the first predetermined water level, the above-mentioned water is described in [S13]. The recovery operation control is terminated, and the state returns to the initial state before [S1] in which the rated power generation operation is possible.

On the other hand, in [S5], the water detection signal from the water detector WL ₁ at the medium water level was not received even after the lapse of the first predetermined time T1 from the start of the water recovery operation control, that is, the storage. When the recovery of the water level of the reformed water is not sufficient, the control device 30 starts the replenishment control [S7] for replenishing the external water. The first predetermined time T1 refers to a predetermined period of, for example, about 3 hours.

Here, the control device 30 may execute the breakthrough determination control for determining whether or not the external water can be replenished before the execution of the replenishment control [S7].

As a specific example of the breakthrough determination control, the control device 30 determines whether or not the ion exchange resin for external water purification used for water replenishment has "broken", that is, the ion exchange resin for water replenishment has reached the end of its life. Whether or not it has not been detected is detected and determined using a breakthrough determination device, in this example, an electric conductivity meter as a breakthrough detection device.

As an example, in the case of the fuel cell device 100 of the first embodiment, in the flowchart of FIG. 4, an ion exchange resin for water replenishment is formed between the lapse of the first predetermined time T1 [S5] and the start of water replenishment control [S7]. The breakthrough determination control [S6] for determining the breakthrough is performed.

In the breakthrough determination control [S6], the purification-treated removal of the inside of the second ion exchange resin container 64 is performed by using the electric conductivity meter WC ₁ arranged in the upper part of the second ion exchange resin container 64. It is confirmed whether or not the conductivity J of the ionized water is a value equal to or less than a predetermined predetermined conductivity J1.

Then, in the breakthrough determination control [S6], the control device 30 is used for external water purification when the measured conductivity J is a predetermined conductivity J1 or less, that is, “No (Good)” that has not broken through. It is determined that the ion exchange resin has not reached the end of its life and is functioning normally, and the water replenishment control [S7] described later is started or executed.

Further, in the breakthrough determination control [S6], when the measured conductivity J exceeds the predetermined conductivity J1, that is, the ion exchange resin for purifying external water has reached the end of its life and has broken through. If it is determined to be "Good)", the refilling using external water is stopped, and the fuel cell shifts from the power generation operation to the control [standby state: S14] for stopping the operation. That is, the power generation operation is stopped before the amount of reformed water stored in the reformed water tank 6 drops to a dangerous level, in other words, before the power generation operation accompanied by the issuance of the drought alert is stopped.

In the above example, the breakthrough determination control [S6] is performed using the conductivity J of the purified deionized water as a reference or a determination item, but other measured values may be used as the determination condition. can. For example, if a flow meter for measuring the inflow of tap water, which is external water, into the second ion exchange resin container 64 per hour, or a water meter, etc., the values obtained from those sensors, That is, the amount of water may be integrated and the value of the cumulative amount of water may be used as an index for determining the breakthrough of the ion exchange resin for refilling water.

Further, for example, the inflow amount of the tap water, which is the external water, into the _second ion exchange resin container 64 is set to the time when the water stop valve V1 arranged in the water supply flow path G is opened. If it can be calculated by calculation based on the water pressure, flow rate, etc. of the external water flowing in the water supply flow path G, the cumulative value obtained by accumulating the valve opening time flows into the second ion exchange resin container 64. As the cumulative amount of water, it may be used for determining the breakthrough of the ion exchange resin for refilling water.

Next, if it is determined in the breakthrough determination control [S6] for determining the breakthrough of the ion exchange resin for water replenishment that there is no breakthrough, the external water is the reformed water which is the first tank. The "replenishment control" [from S7 to S10] for replenishing the tank 6 is started.

In the water replenishment control, as shown in the flowchart of FIG. 4, _first , as [S8], the electromagnetic opening / closing type water stop valve V1 provided in the water supply flow path G for introducing external water is opened to the outside. Tap water, which is water, is introduced into the second ion exchange resin container 64, and refilling is started. Hereinafter, the external water will be referred to as "tap water".

Then, while checking the amount of the stored reforming water in the reforming water tank 6, the replenishment of tap water is continued. That is, in [S9] of the flowchart, as in the case described above, whether or not the amount of reformed water stored in the reforming water tank 6 has dropped to a dangerous drought level is determined by the low water level position. Continue to replenish tap water while checking the water detection signal of the water detector WL ₂ .

If the water detection signal from the water detector WL ₂ at the low water level is interrupted during the refilling water, the refilling water is interrupted because of drought or some abnormality, and the power generation operation is stopped with the issuance of the drought alert. [S15]. If the power generation operation is stopped with the issuance of the drought alert [S15], the operation can be restarted by performing maintenance by human hands.

Next, in [S10] of the flowchart, when the control device 30 can receive the water detection signal from the water detector WL ₁ at the medium water level which is the first predetermined water level, the storage reform in the reforming water tank 6 is performed. Judging that the amount of quality water has recovered, the water stop valve _V1 is closed to stop the introduction of tap water [S11]. Then, the above-mentioned water replenishment control and the water recovery operation control in which the power generation output is suppressed are terminated, and the process returns to the steady operation [S1].

As described above, in the fuel cell device 100 of the present embodiment, even when the amount of reformed water is insufficient and the water recovery operation control is performed, if the control is continued for a certain period of time, the external water is used. By replenishing water, the power generation operation can be continued.

That is, in the fuel cell device having the conventional configuration, if the water required for the power generation operation cannot be secured even if the amount of reformed water is restored or controlled, the device is forcibly stopped and maintenance is performed manually. In many cases, operation could not be resumed until it was completed.

In the fuel cell device, the control device, and the control program of the present embodiment, even if the water required for the power generation operation cannot be secured even if the water amount recovery operation or control of the reforming water is performed, the stop of the device with maintenance is avoided. To. As a result, efficient power generation operation can be continued.

In addition, by controlling the water recovery operation before replenishing water, the number of times of replenishment of external water can be reduced as much as possible, the deterioration of the function of the ion exchange resin for purifying external water can be suppressed, and the life of the ion exchange resin can be extended. can.

Next, as illustrated in the above-mentioned flowchart of FIG. 4, when water cannot be replenished due to the breakage of the ion exchange resin for replenishment and the power generation operation of the fuel cell device is stopped, that is, from [S6] to [S14] in the replenishment. ], The fuel cell device in the operation standby state is subjected to the flow of the first power generation restart control shown in FIG. 5A described later or the flow of the second power generation restart control shown in FIG. 5B. It is automatically programmed or controlled to aim to resume power generation operation.

More specifically, as an example, when the flow shown in FIG. 5A is applied, the fuel cell device in the standby state is first set in [S20] for a period T2 which is a predetermined second predetermined time. Stand by while the fuel cell power generation operation is stopped. The second predetermined time T2 is a predetermined period, for example, about one day.

When the above-mentioned standby period T2 ends, the control device 30 starts the first operation restart control [S21-1]. The first operation restart control [S21-1] is currently performed in [S22-1] based on the standard time of the fuel cell device installation location, such as the Japanese standard time, from an external time server or the like via the built-in clock or communication line. The first predetermined time, which is set in advance in a time zone where the outside temperature is estimated to be relatively low, such as 2:00 am or 3:00 am at midnight, is obtained by acquiring the time, so-called local time. It is executed when the standby period T2 ends for the first time, and the fuel cell apparatus shifts from the above-mentioned standby state to the start preparation control for restarting the power generation operation.

On the other hand, when the flow of the second operation restart control shown in FIG. 5B is applied, the fuel cell device in the standby state is first determined in advance in [S20] as in the first operation restart control of FIG. 5A. During the period T2, which is the second predetermined time, the fuel cell power generation operation is stopped and stands by.

Then, when the standby period T2 ends, the control device 30 starts the second operation restart control [S21-2]. The second operation restart control [S21-2] confirms the temperature of the water temperature gauge TS ₁ arranged in the heat cycle HS system heat storage tank 5 which is the second tank in [S22-2], and confirms the temperature thereof. When the water temperature is equal to or lower than the predetermined first predetermined temperature M1, the fuel cell device shifts from the above-mentioned standby state to the start preparation control for restarting the power generation operation.

The start-up preparation control is a mode for preparing for the restart of the power generation operation, for example, starting the air blower B2 that sends air into the fuel cell module. Further, the [S20] of waiting while the power generation operation is stopped during the period T2 which is the second predetermined time can be omitted. That is, it may be controlled to immediately execute the first operation restart control (see flow FIG. 5A) or the second operation restart control (see flow FIG. 5B) after stopping the power generation operation in [S14].

The first predetermined temperature M1 is, for example, 47 ° C. Further, in the present embodiment, when the measured water temperature M exceeds 47 ° C., the control device 30 may perform heat medium cooling control for lowering the temperature of the heat medium in the heat storage tank 5.

The heat medium cooling control is, for example, to lower the temperature of the heat medium in the heat storage tank 5 between the stop of the power generation operation and the start of the start preparation control so that the amount of condensed water recovered increases after the power generation operation is restarted. It is a control to prepare. The heat medium can be cooled by operating the cooling device. Examples of the cooling device include a heat cycle HS system heat medium circulation pump P2 and a radiator 4. For example, the heat cycle HS system heat medium circulation pump P2 may be operated and the radiator 4 may be operated.

Further, the heat medium cooling control may be executed between the stop of the power generation operation and the start of the start preparation control. Flow As shown in FIG. 5A, after the first predetermined time has passed [S22-1] and before the power generation operation is restarted [S23], the heat medium cooling control is started, and the heat medium cooling control is performed for a predetermined time. It may be continued or may be continued until the heat medium becomes the first predetermined temperature or less. Further, as shown in the flow diagram 5B, after starting the second operation restart control [S21-2], the heat medium cooling control is started and continued until the heat medium reaches the first predetermined temperature or less [S22-2]. You may.

By the above control, even if the fuel cell device 100 of the present embodiment cannot be refilled, the operation is stopped before the drought alert is issued, and the operation is restarted after the environment is set so that the water level can be restored. Can be done.

That is, the fuel cell device 100 restarts the power generation operation without manual maintenance even if the water required for the power generation operation cannot be secured even if the reformed water amount recovery operation or control is performed. Can be done. As a result, power generation operation can be performed efficiently.

The control device 30 and the storage device 40 of the fuel cell device 100 can also be realized as a configuration provided outside the fuel cell device 100. Further, it can be realized as a control method including a characteristic control step in the control device 30 according to the present disclosure, or as a control program for causing a computer to execute the above steps.

Further, the cell stack device and the fuel cell module are not limited to SOFC, for example, a solid polymer fuel cell (PEFC), a phosphoric acid fuel cell (PAFC), and a fuel cell (PAFC). , A fuel cell such as a molten carbonate fuel cell (MCFC) may be used.

Next, the control of the fuel cell device of the second embodiment shown in FIG. 6 and FIGS. 7A, 7B, and 7C will be described. Since the configuration of the fuel cell device of the second embodiment is the same as that of the first embodiment described above, detailed description of the configuration, reference numerals, and the like will be omitted unless it is particularly necessary.

The fuel cell device, the control device, and the control program of the second embodiment are different from the first embodiment in the water recovery operation for the purpose of recovering the amount of reformed water in the reformed water tank which is the first tank. If the amount of reformed water required to continue power generation operation cannot be expected to recover even after control, the purified external water will not be replenished as reformed water, and the power generation operation of the fuel cell device will be stopped. It is a point to do.

Therefore, the external water receiving port 61a, the extension pipe 61b, and the external water introduction, which are arranged as a water replenishing device for supplying water to the water tank from the outside, which are necessary in the fuel cell device of the first embodiment. The water supply flow path G including the port 64a, the water stop valve V1, etc., the _second ion exchange resin container 64, and the electric conductivity meter WC ₁ arranged in the second ion exchange resin container 64 are In the fuel cell apparatus of the second embodiment, it is not an indispensable configuration.

The control of the fuel cell device of the second embodiment will be described in detail.
As shown in the flowchart of FIG. 6, in the fuel cell device of the second embodiment, the control device 30 is a predetermined of the reforming water tank 6 which is the first tank during normal time or normal time when no abnormality is detected in the system. The water detection signal from the water detector WL ₁ arranged at the intermediate position of is monitored, and when it is interrupted, the water recovery operation control [S2] is started.

The water recovery operation control [S2] is the first control for increasing the amount of water recovered from the exhaust gas and the amount of water supplied from the reforming water tank 6 to the fuel cell module 1 as in the first embodiment. At least one of the second controls to be reduced is controlled. Since the contents of the first control and the second control are the same as those of the first embodiment, the description thereof will be omitted.

In the water recovery operation control [S2], condensed water can be recovered with maximum efficiency by simultaneously performing at least one of the first control and the second control, if possible, at the same time. The possible points are similar.

Further, during the continuation of this water recovery operation control [S2], in [S3], the control device 30 loses the water detection signal from the water detector WL ₂ at the low water level position, which is the drought position of the reforming water tank 6. If so, the control shifts to the control to stop the power generation operation (see the drought alert in [S12]).

Further, in [S4], if a water detection signal is received from the water detector WL ₁ located at the middle water level, in [S13], the above-mentioned water recovery operation control is terminated and the rated power generation operation is possible. The same applies to the point of returning to a certain [S1] initial state. Further, as in the first embodiment, when the drought alert is issued and the power generation operation is stopped [S12], the operation can be restarted by performing maintenance by human hands.

Then, in [S5], the water detection signal from the medium water level water detector WL ₁ was not received even after the lapse of the third predetermined time T3 from the start of the water recovery operation control, that is, the storage. If the recovery of the water level of the reforming water is not sufficient, the control device 30 shifts to the control of stopping the power generation operation [S30]. In this case, since there is water above the low water level position, which is the drought position of the reforming water tank 6, the power generation operation is stopped without issuing a drought alert.

Next, as described above, when the power generation operation of the fuel cell device is stopped because the recovery of the water level of the reformed water is not sufficient even if the water recovery operation control is performed, the fuel of the second embodiment in the standby state is used. As a next step, the battery device is automatically programmed or controlled to aim at restarting the power generation operation as shown in the flow shown in FIGS. 7A, 7B or 7C described later.

To explain in detail, first, as an example, when the flow shown in FIG. 7A is applied, the fuel cell device in the standby state is first set in [S40] for a period T4 which is a predetermined fourth predetermined time. , Stand by with the fuel cell power generation operation stopped. The fourth predetermined time T4 is a predetermined period, for example, about one day.

When the above-mentioned standby period T4 ends, the control device 30 starts the first operation restart control [S41-1]. The first operation restart control [S41-1] is the same as in the first embodiment, in [S42-1], from an external time server or the like via a built-in clock or a communication line, a fuel cell device such as Japanese standard time. The current time based on the standard time of the installation location, so-called local time, is acquired, and the current time is preset in a time zone where the outside temperature is estimated to be relatively low, for example, 2:00 am or 3:00 am at midnight. The second predetermined time is executed when the second predetermined time is reached for the first time after the end of the standby period T4, and the fuel cell apparatus shifts from the above-mentioned standby state to the start preparation control for restarting the power generation operation.

The control device 30 may perform heat medium cooling control for lowering the temperature of the heat medium in the heat storage tank 5. Similar to the first embodiment, after the second predetermined time has passed [S42-1], the above-mentioned heat medium cooling control is started before shifting to the start preparation control [S43] for restarting the power generation operation. Therefore, the heat medium cooling control may be continued for a predetermined time, or may be continued until the heat medium becomes a predetermined temperature or lower.

The start-up preparation control is a mode for preparing for the restart of the power generation operation, for example, starting the air blower B2 that sends air into the fuel cell module. Further, the [S40] of waiting with the power generation operation stopped during the period T4, which is the fourth predetermined time, can be omitted. That is, after stopping the power generation operation in [S30], it may be controlled to immediately execute the first operation restart control (see flow FIG. 7A) or the second operation restart control (see flow FIG. 7B).

On the other hand, when the flow of the second operation restart control shown in FIG. 7B is applied, the fuel cell device in the standby state is, as in the first embodiment, first, in [S40], a predetermined fourth predetermined. During the period T4, which is the time, the fuel cell power generation operation is stopped and waits.

Then, when the standby period T4 ends, the control device 30 starts the second operation restart control [S41-2]. The second operation restart control [S41-2] confirms the temperature of the water temperature gauge TS ₁ arranged in the heat cycle HS system heat storage tank 5 which is the second tank in [S42-2], and confirms the temperature thereof. If the water temperature is equal to or lower than the predetermined second predetermined temperature M2, the fuel cell device shifts from the above-mentioned standby state to the start preparation control for restarting the power generation operation. The second predetermined temperature M2 is, for example, 47 ° C.

Next, as another example, when the flow shown in FIG. 7C is applied, the fuel cell device in the standby state is first subjected to a predetermined fourth predetermined time in [S40] as in the above example. During T4 for a certain period, the fuel cell power generation operation is stopped and waits.

Then, when the standby period T4 ends, the control device 30 is connected to the heat cycle HS system heat storage tank 5 which is the second tank in [S42-3] as in [S42-2] of the second operation restart control. If the temperature of the disposed water temperature gauge TS ₁ is confirmed and the water temperature is equal to or lower than the predetermined second predetermined temperature M2, the fuel cell device is directed to restart the power generation operation from the above-mentioned standby state. Shift to start-up preparation control [S44].

However, in the above [S42-3], when the temperature of the water temperature gauge TS ₁ arranged in the second tank exceeds 47 ° C., which is the second predetermined temperature M2, the control device 30 is described below. After executing the heat medium cooling control [from S50 to S56] to lower the temperature of the heat medium in the heat storage tank 5, the process shifts to the start-up preparation control [S44]. The heat medium cooling control [from S50 to S56] can also be executed as a subroutine independent of other conditions.

When the heat medium cooling control [from S50 to S56] is started in [S50], first, as shown in the flowchart of FIG. 7C, the heat cycle HS system heat medium circulation pump P2 is operated in [S51], and [ S52] controls the operation of the fan of the radiator 4.

Then, in [S53], the heat medium circulation pump P2 and the fan of the radiator 4 are operated during the period T5, which is a predetermined fifth predetermined time in which the temperature of the heat medium in the heat storage tank 5 is sufficiently lowered. After waiting, the fan of the radiator 4 is stopped [S54], the heat medium circulation pump P2 is stopped [S55], and the heat medium cooling control is terminated [S56].

By this heat medium cooling control [from S50 to S56], the temperature of the heat medium in the heat storage tank 5 is lowered as much as possible, and preparations are made so that the amount of condensed water recovered increases after the above-mentioned power generation operation is restarted.

With the above control, the fuel cell device 100 of the second embodiment can be restarted after the operation is stopped before the drought alert is issued and the water level can be restored. That is, the fuel cell device 100 can efficiently perform the power generation operation because the power generation operation can be restarted without going through maintenance.

As in the first embodiment, in the second embodiment, the control device 30 and the storage device 40 of the fuel cell device 100 can be realized as a configuration provided outside the fuel cell device 100. Further, it can be realized as a control method including a characteristic control step in the control device 30 according to the present disclosure, or as a control program for causing a computer to execute the above steps.

Further, the cell stack device and the fuel cell module are not limited to SOFC, for example, a solid polymer fuel cell (PEFC), a phosphoric acid fuel cell (PAFC), and a fuel cell (PAFC). , A fuel cell such as a molten carbonate fuel cell (MCFC) may be used.

Moreover, the present disclosure can be carried out in various other forms without departing from its spirit or key characteristics. Therefore, the embodiments described above are merely examples in all respects, and the scope of the present disclosure is set forth in the claims and is not bound by the text of the specification. Furthermore, all modifications and changes that fall within the scope of the claims are within the scope of the present disclosure.

1 Fuel cell module 5 Heat storage tank (second tank)
6 Remodeling water tank (1st tank)
61 1st reformed water tank 62 2nd reformed water tank 63 1st ion exchange resin container 64 2nd ion exchange resin container 30 Control device 40 Storage device 100 Fuel cell device

V ₁ Water stop valve G Water supply flow path R Reform water flow path P1 Reform water pump TS ₁ Coolant temperature gauge WC ₁ Electric conductivity meter WL ₁ Water level sensor (medium water level sensor)
WL ₂ Water detector (low water level sensor)

Claims (5)

With a fuel cell
A first tank for storing water recovered from the exhaust gas discharged from the fuel cell to supply the fuel cell, and a first tank.
A water level detection device that detects the height of the water surface in the first tank, and
A control device that controls the operation of the fuel cell and each auxiliary machine attached to the fuel cell, and
A water supply device that supplies water to the first tank from the outside,
A second tank that stores a heat medium that exchanges heat with the exhaust gas,
A fuel cell device including a heat medium temperature measuring device for measuring the temperature of the heat medium in the second tank.
The water supply device is
A water replenishment flow path that allows water replenished from the outside to flow through the first tank,
The ion exchange resin located in the water supply flow path and
It has a breakthrough determination device for determining that the ion exchange resin has broken down, and has a breakthrough determination device.
The control device is
The first control that controls the operation of each auxiliary machine so that the amount of water recovered from the exhaust gas increases when the water level in the first tank becomes equal to or lower than a predetermined first predetermined water level. ,and,
Of the second controls that control the operation of each auxiliary machine so that the amount of water supplied from the first tank to the fuel cell is reduced.
Execute water recovery operation control that controls at least one,
When the water level in the first tank measured by the water level detection device is equal to or lower than the first predetermined water level after a predetermined first predetermined time has elapsed from the start of the water recovery operation control, the said The breakthrough determination device executes a breakthrough determination control for determining whether or not the ion exchange resin is broken, and in the breakthrough determination control, it is determined that the ion exchange resin is not broken. When the water replenishment device executes a refilling control for replenishing the first tank with a predetermined amount of external water, and the breakthrough determination control determines that the ion exchange resin has broken through. The control to stop the power generation operation of the fuel cell device is executed, and the control is executed.
The control device is
When the predetermined first time included in the time zone when the outside air temperature is low is reached, the first operation restart control for restarting the power generation operation of the fuel cell device and
When the heat medium temperature measured by the heat medium temperature measuring device is equal to or lower than a predetermined first predetermined temperature, the second operation restart control for restarting the power generation operation of the fuel cell device can be executed. can be,
The control device is a fuel cell device that executes one of the first operation restart control and the second operation restart control after executing the control for stopping the power generation operation. The control device executes one of the first operation restart control and the second operation restart control after waiting for a predetermined second predetermined time from the stop of the power generation operation. , The fuel cell device according to claim 1. A cooling device for cooling the heat medium in the second tank is further provided.
The control device is a preparation for performing the power generation operation of the fuel cell device, which is executed after executing the control to stop the power generation operation of the fuel cell device and after executing the operation restart control. The fuel cell apparatus according to claim 1 or 2, wherein the heat medium cooling control for cooling the heat medium is executed before the preparation control is executed. A control device that controls a fuel cell device equipped with a fuel cell.
The first control that controls the operation of each auxiliary machine attached to the fuel cell so that the amount of water recovered from the exhaust gas discharged from the fuel cell increases.
Each auxiliary device attached to the fuel cell so that the amount of water supplied to the fuel cell from the first tank stored for supplying the water recovered from the exhaust gas discharged from the fuel cell to the fuel cell is reduced. The second control that controls the operation of
A water replenishment control that replenishes a predetermined amount of external water to the first tank by a water replenishing device that replenishes water to the first tank from the outside, and
A breakthrough determination control that determines whether or not the ion exchange resin located in the water supply flow path that causes the water supplied from the outside to flow through the first tank is broken.
When the predetermined first time included in the time zone when the outside air temperature is low is reached, the first operation restart control for restarting the power generation operation of the fuel cell device and
When the temperature of the heat medium in the second tank that stores the heat medium that exchanges heat with the exhaust gas is equal to or lower than the predetermined first predetermined temperature, the second operation is restarted to restart the power generation operation of the fuel cell device. Control and
Power generation operation stop control for stopping the power generation operation of the fuel cell device, and
Is feasible and
When the water level in the first tank becomes equal to or lower than a predetermined first predetermined water level, a water recovery operation control that controls at least one of the first control and the second control is executed.
After the water recovery operation control is executed and continued for a predetermined first predetermined time, when the water level in the first tank is equal to or lower than the first predetermined water level, the breakthrough determination control is executed and the said. When it was determined in the breakthrough determination control that the ion exchange resin was not broken, the water replenishment control was executed, and in the breakthrough determination control, it was determined that the ion exchange resin was broken. When, the power generation operation stop control is executed,
A control device that executes one of the first operation restart control and the second operation restart control after executing the power generation operation stop control. For a control device that controls a fuel cell device equipped with a fuel cell,
When the water level in the first tank stored for supplying the water recovered from the exhaust gas discharged from the fuel cell to the fuel cell becomes equal to or lower than the predetermined first predetermined water level, the water is recovered from the exhaust gas. A first water recovery operation control step for performing a first control for controlling the operation of each auxiliary machine attached to the fuel cell so that the amount of water increases, and
Each attached to the fuel cell so that the amount of water supplied from the first tank to the fuel cell decreases when the water level in the first tank becomes equal to or lower than a predetermined first predetermined water level. A second water recovery operation control step for performing a second control for controlling the operation of the auxiliary machine, and
A water replenishment control step for replenishing the first tank with a predetermined amount of external water by a water replenishing device for replenishing the first tank from the outside.
A breakthrough determination control step for determining whether or not the ion exchange resin located in the water supply flow path for flowing water supplied from the outside to the first tank has broken through, and a breakthrough determination control step.
A first operation restart control step for restarting the power generation operation of the fuel cell device when a predetermined first time included in a predetermined time zone when the outside air temperature is low is reached.
When the temperature of the heat medium in the second tank that stores the heat medium that exchanges heat with the exhaust gas is equal to or lower than the predetermined first predetermined temperature, the second operation is restarted to restart the power generation operation of the fuel cell device. Control steps and
A power generation operation stop control step for stopping the power generation operation of the fuel cell device, and
It is a control program that executes
After at least one of the first water recovery operation control step and the second water recovery operation control step continues for a predetermined first predetermined time, the water level in the first tank becomes the first predetermined water level. In the following cases, the breakthrough determination control step is executed, and when it is determined in the breakthrough determination control step that the ion exchange resin has not broken down, the water replenishment control step is executed and the breakthrough is performed. When it is determined in the determination control step that the ion exchange resin has broken, the power generation operation stop control step is executed.
After executing the power generation operation stop control step, an operation restart control step for executing one of the first operation restart control step and the second operation restart control step, and the operation restart control step.
A control program that executes.

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