JPH1131521A - Fuel cell system and power load prediction device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance power load follow-up capability by adjusting the capability of a reforming means which reforms raw fuel into reformed fuel causing it to react with oxygen in a fuel cell main body according to power load prediction using a power load schedule model. SOLUTION: Excess reformed fuel is utilized for heating a reforming means, is stored, power generation is conducted according to a power load by adjusting the reformed fuel and an oxygen amount in oxidizing gas containing oxygen, and exhaust is utilized for heating the reforming means. Preferably, a power load schedule model is information formed using power load actual record, calender information, weather and climate conditions regarding the presence or absence of persons. In a power load schedule model 116, the reformed fuel fed to a fuel cell module 131 is increased by a fuel control valve 135 before the time of actual load rise occurrence, so as to start to increase the, output of a fuel feed device 121 and is started to decrease before the time of the occurrence for load decrease. The production amount of the reformed fuel is adjusted, and the excess reformed fuel is utilized in a burner 123 so as to suppress the utilization factor deterioration of raw material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a power load following capability of a fuel cell system utilizing generated power of a fuel cell.

[0002]

2. Description of the Related Art Conventionally, a fuel cell system disclosed in Japanese Patent Application Laid-Open No. 57-21276 has been constructed as shown in FIG.

In this system, a reformer 30 produces a hydrogen-rich fuel gas from a raw material gas, sends the fuel gas to an anode electrode of a fuel cell main body 10, and reacts hydrogen with oxygen supplied to a cathode electrode 12 to generate electric power. And take out the exhaust heat. The residual hydrogen in the exhaust fuel gas is used as fuel for the burner 51 that heats the reformer 10.

The active power detection unit 71
When the output increases, the calculation unit 70 calculates the valve opening set value corresponding to the output and increases the valve opening of the fuel gas flow control valve V4 via the flow controller C4.

At the same time, a set value for reducing the valve opening of the valve V6 is supplied to the flow controller C6 of the burner fuel regulating valve V6. Control is performed to increase the output of the quality device.

At this time, since the pressure in the fuel chamber of the fuel cell is controlled at a constant value for the purpose of preventing an excessive pressure difference, the pressure regulating valve V5
The burner fuel flow rate changes as a result of the above control, but this is finely adjusted by the flow rate controller C6 by the feedback signal from the flow rate measuring section Q6.

In other words, the prior art is a method of following the fluctuation of the power load by adjusting the fuel supply amount and the amount of heat generated by the burner according to the detected power load.

[0008] Alternatively, as a means for improving the load followability with a simple structure, a reformed fuel tank is provided between a reformer and a fuel cell main body to accumulate reformed fuel as disclosed in Japanese Patent Application Laid-Open No. 57-180082. A method of following a load change has been proposed.

[0009]

However, in the conventional method of adjusting the fuel supply amount according to the detected power load, when the load increases, the output of the reformer is increased while increasing the power generation amount. Therefore, there is a limit to the ability to follow a sudden load change.

Further, in a system in which a reformed fuel tank is provided to follow a load change, a large amount of reformed fuel needs to be accumulated in order to follow a large load change, and there is a danger of explosion and the like as compared with other fuels. Since a high reformed fuel is always stored in a required amount or more, a system with higher safety is desired.

An object of the present invention is to solve such a conventional problem, and an object of the present invention is to provide a fuel cell system which is superior in load followability or safety.

[0012]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention comprises a power load prediction device and a reforming means for adjusting the capacity according to the output of the power load prediction device.

[0013] The power load predicting device includes past power load results, calendar information, information on weather and weather conditions, presence / absence information of a person in the target area, operation information of a device consuming power, and information of a person in the target area. A power load schedule model is created or corrected using one of the schedule information on the presence / absence and the schedule information on the operation of a device consuming power, and predicts the power load.

Thus, excellent load following performance can be obtained.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 comprises a power load predicting device for predicting a power load, and a reforming means for heating the material to an appropriate temperature to generate reformed fuel from raw fuel. The amount of reformed fuel generated by the reforming means is adjusted based on the load prediction information of the load prediction device.

Thus, by predicting the power load and adjusting the capacity of the reforming means so as to obtain a required amount of reformed fuel, excellent follow-up performance when the power load fluctuates can be realized.

According to a second aspect of the present invention, there is provided a power load prediction device for predicting a power load, and a reforming means for generating a reformed fuel from raw fuel by being heated to an appropriate temperature. The amount of reformed fuel generated by the reforming unit is adjusted based on the load prediction information, power generation is performed in accordance with the power load, and excess reformed fuel is used for heating the reforming unit.

Thus, by predicting the power load and adjusting the capacity of the reforming means so as to obtain a required amount of reformed fuel, it is possible to realize excellent followability when the power load fluctuates.

Further, by using the surplus reformed fuel for heating the reforming means, it is possible to suppress a decrease in fuel utilization efficiency when the reformed fuel is excessively supplied with respect to the power generation amount.

According to a third aspect of the present invention, there is provided an electric power load estimating apparatus comprising: an electric power load estimating apparatus for estimating an electric power load; and reforming means for generating reformed fuel from raw fuel heated to an appropriate temperature. The reformed fuel generation amount of the reforming unit is adjusted based on the load prediction information, power generation is performed in accordance with the electric power load, and excess reformed fuel is stored in the reformed fuel storage unit.

Thus, by predicting the power load and adjusting the capacity of the reforming means so as to obtain a required amount of reformed fuel, excellent followability can be realized when the power load fluctuates.

Further, by storing the surplus reformed fuel in the reformed fuel storage means, it is possible to suppress a decrease in fuel use efficiency when the reformed fuel is excessively supplied with respect to the power generation amount.

Further, by predicting the electric power load and adjusting the capacity of the reforming means so as to obtain a required amount of reformed fuel, it is not necessary to constantly store a large amount of reformed fuel, thereby improving safety.

According to a fourth aspect of the present invention, there is provided an electric power load estimating apparatus comprising: a power load estimating apparatus for estimating an electric power load; and a reforming means for generating reformed fuel from raw fuel by being heated to an appropriate temperature. In addition to adjusting the amount of reformed fuel generated by the reforming means based on the load prediction information, the amount of oxygen in the oxidizing gas is adjusted to generate power in accordance with the power load, and the surplus reforming contained in the reformed fuel exhaust is adjusted. High quality fuel is used for heating the reforming means.

Thus, by predicting the power load and adjusting the capacity of the reforming means so as to obtain a required amount of reformed fuel, it is possible to realize excellent followability when the power load fluctuates.

Further, by using the surplus reformed fuel for heating the reforming means, it is possible to suppress a decrease in fuel utilization efficiency when the reformed fuel is excessively supplied with respect to the power generation amount.

According to a fifth aspect of the present invention, there is provided an electric power load estimating apparatus comprising an electric power load estimating apparatus for estimating an electric power load, and a reforming means for generating reformed fuel from raw fuel by being heated to an appropriate temperature. In addition to adjusting the amount of reformed fuel generated by the reforming means based on the load prediction information, the amount of oxygen in the oxidizing gas is adjusted to generate power in proportion to the power load, and part of the surplus reformed fuel is reformed. Used directly for heating means.

Thus, by predicting the power load and adjusting the capacity of the reforming means so as to obtain a required amount of reformed fuel, it is possible to realize excellent followability when the power load fluctuates.

Further, by using the surplus reformed fuel for heating the reforming means, it is possible to suppress a decrease in fuel utilization efficiency when the reformed fuel is excessively supplied with respect to the power generation amount.
The combustion stability can be improved by directly using the reformed fuel.

According to a sixth aspect of the present invention, there is provided an electric power load estimating apparatus for estimating an electric power load, and a reforming means for generating reformed fuel from raw fuel heated to an appropriate temperature. The amount of reformed fuel generated by the reforming means is adjusted based on the load prediction information, and the amount of oxygen in the oxidized gas is adjusted using the oxidized gas exhaust to generate power in accordance with the electric power load. The surplus reformed fuel contained therein is used for heating the reforming means.

Thus, by predicting the power load and adjusting the capacity of the reforming means so as to obtain a required amount of reformed fuel, it is possible to realize excellent followability when the power load fluctuates.

Further, by using the surplus reformed fuel for heating the reforming means, it is possible to suppress a decrease in fuel use efficiency when the reformed fuel is excessively supplied with respect to the power generation amount.

Further, by adjusting the amount of oxygen in the oxidizing gas, it becomes easy to balance the pressure between the reformed fuel and the oxidizing gas in the fuel cell main body, thereby improving the reliability of the fuel cell system. it can.

According to a seventh aspect of the present invention, a power load schedule model is created or modified based on the actual power load,
This is to predict the power load.

As a result, it is possible to incorporate the power load fluctuation pattern peculiar to each system into the schedule model, and it is possible to improve the accuracy of power load prediction.

According to the present invention, a power load schedule model is created or corrected using calendar information to predict a power load.

This makes it possible to incorporate into the schedule model the fluctuation pattern of the power load caused by the characteristics of the calendar such as month, day, weekday, weekday and holiday.
The accuracy of power load prediction can be improved.

According to a ninth aspect of the present invention, a power load schedule model is created or corrected based on information on weather and weather conditions in a power supply area, and a power load is predicted.

This makes it possible to incorporate into the schedule model the fluctuation pattern of the power load caused by the weather and weather conditions such as the amount of solar radiation, precipitation, snowfall, snowfall, temperature, humidity, etc. Accuracy can be improved.

According to a tenth aspect of the present invention, a power load schedule model is created or corrected using information on the presence or absence of a person in a power supply area, and fluctuations in power load are predicted.

As a result, it is possible to incorporate the fluctuation pattern of the power load caused by the presence or absence of a person into the schedule model, thereby improving the accuracy of the power load prediction.

According to an eleventh aspect of the present invention, a power load schedule model is created or corrected by using operation information of a device that consumes power in a power supply area, and fluctuations in power load are predicted.

As a result, it is possible to incorporate into the schedule model the fluctuation pattern of the power load caused by the operation state of the power consuming device, and it is possible to improve the accuracy of the power load prediction.

According to a twelfth aspect of the present invention, a power load schedule model is created or corrected using schedule information on the presence or absence of a person in a power supply area, and a power load is predicted.

As a result, information on the presence or absence of a person can be obtained in advance, and the accuracy of power load prediction can be further improved.

According to a thirteenth aspect of the present invention, a power load schedule model is created or corrected using schedule information on the operation of a device that consumes power in a power supply area, and fluctuations in power load are predicted.

As a result, it is possible to grasp the operating state of the device consuming power in advance, and it is possible to further improve the accuracy of power load prediction.

[0048]

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

(Embodiment 1) As shown in FIG.
Power load prediction device 110 and reformer 12 as reforming means
0 and the fuel cell main body 130.

In the power load prediction device 110, the information 181 including calendar information and the actual load information 184 are received, the model creation unit 111 creates or corrects the power load schedule model 116, and stores it in the model storage unit 112.

The information 194 includes information on weather and weather conditions, information on the presence or absence of a person in the power supply area, operation information on a device consuming power, scheduled information on the presence or absence of a person in the power supply area, and a device consuming power. It consists of schedule information related to the operation of the vehicle.

Then, the prediction information generation unit 113 refers to the power load schedule model 116, makes a correction using the information 194, and calculates the predicted load after a predetermined time.
Send as 82.

By using the actual load information 184, the power load schedule model 116 can be created. If the created power load schedule model is compared with the actual load and corrected, the accuracy of the model can be further improved.

By associating calendar information such as month, day, day of the week, weekday and holiday, and time with the actual load information 184, a power load schedule model taking into account the characteristics of the power load schedule for the calendar specific to the power supply target area. Can be created. In other words, the seasonal influence on the air-conditioning load and the tendency of the electric power load such as the operation status of the facilities and devices can be characterized by a rough classification that is not directly related to the current status of the calendar.

The amount of solar radiation, precipitation, snowfall, snowfall,
Information on weather and weather conditions such as temperature and humidity;
By associating the actual load information 184, it is possible to indirectly infer the operation status of facilities such as air conditioning and lighting, and to predict the power load.

Further, by associating the presence / absence information of a person in the target area, such as where and how many people are, with the actual load information 184, it is possible to predict the power load resulting from the presence / absence of a person. Actually, an electric power load is generated because a person is present in many cases, and an operation state of facilities such as an air conditioner and a lighting varies depending on the state of the person.

Further, by associating the operation information of the power consuming device, such as the operating rate of the air conditioner, the kitchen equipment, or the illuminator or other equipment, with the actual load information 184, the operation status of the power consuming device can be determined. The power load resulting from the difference can be predicted. According to this, since the operating status of the air conditioner, the lighting, and other facilities is directly known, the power load can be predicted with high accuracy.

Further, by using schedule information on the presence or absence of a person, for example, event information such as a party or a meeting, it is possible to predict the operation status of air conditioning, lighting, and other facilities, and to predict the power load.

Further, by directly knowing information on the operation schedule of the power consuming device, such as the setting of the timer of the air conditioner and the operation schedule of the equipment, it is possible to predict a change in the power load schedule.

The above is a description of the power load prediction device 11 when the power supply area is a home, a factory, an office, or a specific area.
However, the same effect can be expected in a fuel cell system for a vehicle. In the case of a car, it goes without saying that a device that consumes power includes a driving motor in addition to an air conditioner and lighting.

The schedule information relating to the presence or absence of a person is particularly effective for a bus or the like, and the schedule information relating to the operation of a device that consumes power includes road conditions from a car navigation system to a destination, congestion information, and map data. It is also possible to use it.

In the reformer 120, the fuel supply device 121 mixes the city gas 151 of the raw fuel and the water 152 at an appropriate ratio based on the load prediction information 182 and the actual load information 184, and supplies the mixed gas to the reforming catalyst section 122. And a city gas 154 used to heat the reforming catalyst unit 122 is sent to the burner 123 corresponding to the heating unit.

In the reforming catalyst section 122, steam reforming of city gas is performed by a catalytic action, and hydrocarbons containing methane as a main component in the fuel gas are decomposed into hydrogen and carbon dioxide to become reformed fuel 153. . About 7 steam reforming reactions of city gas
Since the endothermic reaction occurs in an atmosphere temperature of 00 ° C. to 800 ° C., the reforming catalyst section 122 is heated by the burner 123 to obtain heat corresponding to the supply amount of the fuel gas.

The burner 123 burns the city gas 154 and the exhaust fuel 155 which is the exhaust of the reformed fuel 153 from the fuel cell module 131. City gas 1
The flow rate 54 indicates the load prediction information 182 and the actual load information 184.
Is determined by the fuel supply device 121 based on the
The amount of 55 is determined by the fuel supply device 121, the fuel control valve 135, and the external exhaust control valve 136.

In the fuel cell main body 130, the reformed fuel 153 mainly containing hydrogen and containing carbon dioxide and water vapor is supplied to the fuel control valve 1 according to a fuel control signal 185 from the control device 133.
The flow rate is adjusted by 35 and supplied to the hydrogen electrode of the fuel cell module 131 using the solid polymer membrane as an electrolyte.

On the other hand, the air pump 132
The air 172 that is an oxidizing gas is supplied to the air electrode of the fuel cell module 131 according to the value of the air supply signal 189 from the fuel cell module 131. The oxygen concentration of the air 172 is adjusted by mixing a part 173 of the air discharged from the air electrode with the outside air 171 by adjusting the flow rate of the air 172 with the circulating air control valve 138.

In the fuel cell module 131, hydrogen supplied to the hydrogen electrode becomes hydrogen ions, moves in the electrolyte, and reacts with oxygen at the air electrode to become water. At this time, the movement of the hydrogen ions becomes a current and electric power can be taken out.

The exhaust from the hydrogen electrode of the fuel cell module 131 contains unreacted residual hydrogen, and the exhaust fuel 1 used in the burner section 123 at the pipe branch 139.
55 and an external exhaust 156. Exhaust fuel 155
The external exhaust 156 is distributed by adjusting the opening of the external exhaust control valve 136 with the external exhaust control signal 187.

On the other hand, the air 172 supplied to the air electrode loses oxygen and is discharged, and is branched into exhaust air 174 and circulating air 173 at a pipe branch 141 to adjust the amount of oxygen in the supplied air. The circulating air control valve 138 controls the exhaust control signal 188 and the circulating air control signal 186.
Is appropriately distributed according to

The load detector 134 detects an actual power load and sends actual load information 184 to the model creating unit 111, the fuel supply device 121, and the control device 133.

Based on the load prediction information 182 and the actual load information 184, the control device 133 controls the power generation amount, the flow rate balance between the reformed fuel and the air, the exhaust fuel 155 and the external exhaust 156.
In order to adjust the distribution of the exhaust air 174 and the circulation air 173, the fuel control valve 135, the external exhaust control valve 136,
The air pump 132, the exhaust control valve 137, and the circulating air control valve 138 are generally controlled.

In the first embodiment, the control device 133 and the reformer 1
Although there is no direct exchange of information with the twenty fuel supply devices 121, both of them operate based on the load prediction information 182 and the actual load information 184, and therefore operate in conjunction with each other.

As for the control method, let us consider a case where the power load schedule model 116 is shown by a solid line in the graph of the time t and the output W in FIG. 4 as an example.

In FIG. 4, the relationship between time t and output W, time t
The solid line in the relationship between the time t and the output W indicates the power load schedule model 116, and the solid line in both graphs indicates the change in the output or fuel flow of the fuel cell system shown in the first embodiment. And broken lines indicate changes in output or fuel flow of a conventional system for detecting and controlling load fluctuation.

While the power load schedule model 116 suddenly rises from Po1 to Po2 at time t1, the conventional system starts increasing the fuel flow rate / output from time t1 when load fluctuation is detected. However, since the heat supply amount in the reformer does not increase rapidly, it takes time (tt2-t1) to obtain the required fuel flow rate, and the output response is Pt1
From Pt2 to Pt2.

In the first embodiment of the present invention, the fuel control valve 135 starts from tn1 before the time t1 when the load actually increases.
Then, the amount of reformed fuel supplied to the fuel cell module 131 is increased, and the output of the fuel supply device 121 is started to increase. Then, the output of the air pump 132 is increased to maintain the pressure balance in the fuel cell module 131, and the exhaust control valve 137 is increased.
By controlling the circulating air control valve 138 to adjust the amount of oxygen in the supplied air, the increase in the power output due to the increase in the supplied fuel is suppressed, the amount of heat generated by the burner 123 is increased, and the fuel supply amount is further increased.

Therefore, the required amount of fuel supply can be made more quickly (tn2−tn1) than in the case of increasing the fuel supply amount while increasing the power generation amount.

In the power supply, by increasing the fuel supply amount, adjusting the air amount, and starting from Pn1 to Pn2 at the maximum speed, excellent responsiveness can be obtained when the load increases.

Further, the power load schedule model 11
In contrast to the sudden decrease in load from Po3 to Po4 from time t3 to tt4 in No. 6, in the conventional system, the output is decreased from Pt3 to Pt4 at the maximum speed from time t3 when the load decrease is detected. Therefore, extra power is generated corresponding to the delay of the system.

In the first embodiment of the present invention, the fuel supply device 12 starts from tn3 before the time t3 when the load actually decreases.
The output of 1, that is, the fuel supply amount is started to be reduced.

The output of the air pump 132 is reduced to maintain the pressure balance in the fuel cell module 131,
By controlling the exhaust control valve 137 and the circulating air control valve 138 to adjust the amount of oxygen in the supplied air, a decrease in the power output due to a decrease in the supplied fuel is suppressed, and a calorific value of the burner section 123 is reduced. Tn3 to t by suppressing unnecessary heat generation
At n4, the required fuel supply amount is reduced after t3.

The power is reduced at the maximum speed from Pn3 to Pn4 by considering the timing of the well-balanced demand and surplus, so that excellent responsiveness can be obtained even when the load decreases.

In the first embodiment, the load prediction information 1
Since the amount of the reformed fuel 153 is adjusted by using the fuel gas 82 and the surplus reformed fuel is used by the burner 123, the fuel cell has excellent responsiveness to the load fluctuation while suppressing the decrease in the use efficiency of the raw fuel. A system can be provided.

In the first embodiment, a polymer electrolyte fuel cell was used. However, other types such as a phosphoric acid type and a solid oxide type are also available.
The same effect can be obtained by using the same as 31.

Similar effects can be obtained by using natural gas, LPG, digestive gas, methanol or the like as raw fuel in addition to city gas.

(Embodiment 2) As shown in FIG.
Power load prediction device 110 and reformer 12 as reforming means
0 and the fuel cell main body 230.

The control device 233 of the fuel cell main body 230
The calculation is performed based on the load prediction information 182 and the actual load information 184, and the control signals 285 and 291 are sent to the battery reformed fuel control valve 235 and the burner reformed fuel control valve 243. Battery reformed fuel control valve 235 and burner reformed fuel control valve 24
3 is adjusted, and the reformed fuel 153 is appropriately distributed to the burner reformed fuel 255 and the cell reformed fuel 257.

The difference from the first embodiment is that the reformed fuel 153 includes a pipe branch 242, a cell reformed fuel control valve 235, and a burner reformed fuel control valve 243.
And the battery reforming fuel 257, and the surplus reforming fuel is directly used as fuel by the burner 123.

In the second embodiment, the load prediction information 1
Since the amount of the reformed fuel 153 is adjusted by using the fuel gas 82 and the surplus reformed fuel is used by the burner 123, the fuel cell has excellent responsiveness to the load fluctuation while suppressing the decrease in the use efficiency of the raw fuel. A system can be provided.

Further, since the reformed fuel is used directly as the burner fuel, the composition ratio of the burner reformed fuel 255 is constant, and the combustion stability in the burner 123 is improved.

Similar effects can be obtained by using a phosphoric acid type or solid oxide type fuel cell as the fuel cell module 131 in the second embodiment, as in the first embodiment.

Similar effects can be obtained by using natural gas, LPG, digestive gas, methanol, etc. in addition to city gas as raw fuel.

(Embodiment 3) As shown in FIG.
Power load prediction device 110 and reformer 32 as reforming means
0 and the fuel cell main body 330.

The difference from the first embodiment is that the burner 323 of the reformer 320 uses only the city gas 154 as the heating fuel, and the fuel cell body 330 has an accumulator 345 corresponding to a reformed fuel storage section, a pressure sensor 346, Control valve 33
5, an air pump 332 for introducing only the outside air 174, and a control device 333.

The accumulator 345 has a function of storing the reformed gas, and can improve the load followability of the output power of the fuel cell module 131. A pressure sensor 346 is attached to the accumulator 345, and a pressure sensor signal 392 is sent to the control device 333 to monitor the internal pressure of the accumulator 345.

The flow rate of the reformed fuel 153 is adjusted by the fuel control valve 335 according to the fuel control signal 385 from the control device 333, and is supplied to the hydrogen electrode of the fuel cell module 131.

The air pump 332 supplies an amount of air 372 corresponding to the value of the air supply signal 389 from the control device 333 to the air electrode of the fuel cell module 131.

The power load detector 134 constantly monitors the power load state, and the power load information 184 is sent to the control device 333 and the load prediction device 110.

Regarding the control method, the load pattern 116
Let us consider an example in which is shown by the solid line in the graph of the time t and the output W in FIG.

In FIG. 5, the relationship between time t and output W, time t
And the pressure inside the accumulator 345.

The load pattern 116 rapidly rises from W1 to W2 at time t1, and falls sharply from W2 to W1 at time t3.
In the steady state, the accumulator 345 corresponding to the output W1
Is P1, and the pressure corresponding to the output W2 is P2.

On the other hand, the fuel cell system of the third embodiment increases the reformed gas supply amount of the fuel control valve 335 by Δt1 before the time t1, and starts increasing the output of the fuel supply device 121.

Next, in order to maintain the pressure balance in the fuel cell module 131, the output of the air pump 332 is increased, the fuel control valve 335 is controlled to adjust the flow rate of the reformed fuel 392, and the power output is adjusted to the actual load.

When the pressure in the accumulator 345 becomes higher by ΔP2 than the pressure P2 corresponding to the output W2 while maintaining the balance between the calorific value of the burner 323 and the fuel supply amount, the power load at that time is met. The fuel supply amount is returned to the original value, the pressure is maintained, and a standby state is entered.

When the power load detector 134 actually detects a load increase at or around the time t1, the fuel control valve 335 and the supplied oxygen amount are immediately adjusted to obtain an output suitable for the load. Thereafter, while maintaining an output corresponding to the load, the amount of fuel supplied is adjusted so as to be a pressure corresponding to the load while adjusting the amounts of air and oxygen.

When the decrease in the load is detected at or before time t3, the reformed fuel 3
The flow rate of 92 is reduced to obtain an output corresponding to the load. Thereafter, while maintaining an output corresponding to the load, the amount of fuel supplied is adjusted so as to be a pressure corresponding to the load while adjusting the amounts of air and oxygen. The load fluctuation at this time is absorbed by the accumulator 345.

When the actual load does not follow the load pattern 116 and does not fluctuate, the standby operation is performed from the time (t1-Δt1) to the time (t3 + Δt3), and then the operation state is returned to an operation state suitable for the load at that time.

In the fuel cell system according to the third embodiment, the accumulator 345 improves the load followability, and sets a standby state in advance of a time when a sudden increase in the load is predicted according to the load pattern 116 while performing feedback control of the power load. It is. Since the reformed gas is accumulated by increasing the pressure, the accumulator 345 can be reduced in size.

Further, a standby state is set in accordance with a more accurate load pattern by learning load fluctuations.

In the third embodiment, the load prediction information 1
Since the amount of reformed fuel 153 generated is adjusted using the value 82 and the surplus reformed fuel is stored in the accumulator 345, excellent responsiveness to load fluctuation can be obtained without impairing the use efficiency of the raw fuel. .

Further, it is possible to provide a fuel cell system which can easily cope with a shift in the load pattern and which is excellent in safety by avoiding accumulation of the reformed gas more than necessary.

Similar effects can be obtained by using a phosphoric acid type or solid oxide type fuel cell as the fuel cell module 131 in the third embodiment, as in the first embodiment.

Similar effects can be obtained by using natural gas, LPG, digestive gas, methanol, etc. in addition to city gas as raw fuel.

[0114]

As is apparent from the above embodiment, the first aspect of the present invention adjusts the reformed fuel generation amount of the reformer using the load prediction information of the power load prediction device. According to the configuration, there is an effect that excellent followability to a load change is obtained.

[Brief description of the drawings]

FIG. 1 is an explanatory view of a fuel cell system showing one embodiment of the present invention.

FIG. 2 is an explanatory diagram of a fuel cell system showing one embodiment of the present invention.

FIG. 3 is an explanatory diagram of a fuel cell system showing one embodiment of the present invention.

FIG. 4 is an explanatory diagram of control according to an embodiment of the present invention.

FIG. 5 is an explanatory diagram of control according to an embodiment of the present invention.

FIG. 6 is an explanatory diagram of a fuel cell system showing the conventional example.

[Explanation of symbols]

 Reference Signs List 110 power load prediction device 111 model creation unit 112 model storage unit 113 prediction information generation unit 120 reformer 121 fuel supply device 122 reforming catalyst unit 123 burner 130 fuel cell body 131 fuel cell module 132 air pump 133 control device 134 load detector

Claims (16)

[Claims] A power load prediction device for predicting the power load using a power load schedule model; a reforming means for reforming a raw fuel heated to an appropriate temperature to generate a reformed fuel containing hydrogen; A fuel cell system, comprising: a fuel cell main body that generates power by reacting the reformed fuel and an oxidizing gas containing oxygen in a power generation reaction unit, and adjusts the capacity of the reforming unit according to the prediction of the power load. 2. The method according to claim 1, wherein power generation is performed according to the power load while adjusting the capacity of the reforming means according to the prediction of the power load, and excess reformed fuel is used for heating the reforming means. The fuel cell system according to claim 1. 3. The fuel cell system according to claim 1, further comprising a reformed fuel storage means for storing the reformed fuel in the fuel cell body, and storing an excess of the reformed fuel. 4. The method according to claim 1, wherein the amount of oxygen in the oxidizing gas used for the power generation reaction is adjusted to generate power according to the power load, and the reformed fuel exhaust gas after the power generation reaction is used for heating the reforming means. 3. The fuel cell system according to claim 1, wherein: 5. The fuel cell body or the reforming means,
3. The fuel cell system according to claim 1, further comprising a pipe branch for distributing the reformed fuel to a power generation reaction section and a heating section of the reforming unit, and sending surplus reformed fuel to a heating section of the reforming unit. Fuel cell system. 6. The fuel cell system according to claim 1, wherein the oxidizing gas exhaust from the power generation reaction section is used to adjust the amount of oxygen in the oxidizing gas. 7. An electric power load predicting apparatus which creates or corrects an electric power load schedule model based on an actual electric power load and predicts an electric power load. 8. An electric power load predicting apparatus that generates or corrects an electric power load schedule model using calendar information and predicts an electric power load. 9. An electric power load predicting apparatus that creates or corrects an electric power load schedule model based on information on weather and weather conditions in an electric power supply area and predicts an electric power load. 10. An electric power load predicting apparatus that creates or corrects an electric power load schedule model using information on the presence or absence of a person in an electric power supply area, and predicts a change in electric power load. 11. A power load prediction device that creates or corrects a power load schedule model using operation information of a device that consumes power in a power supply area, and predicts fluctuations in power load. 12. An electric power load predicting apparatus for preparing or correcting an electric power load schedule model using schedule information on the presence or absence of a person in an electric power supply area, and estimating an electric power load. 13. A power load predicting device that prepares or corrects a power load schedule model using schedule information related to the operation of a device consuming power in a power supply area, and predicts a change in power load. 14. The power load prediction device according to claim 8, wherein one or more of month, day, weekday, weekday and holiday distinction, and time are used as the calendar information. 15. The power load prediction device according to claim 9, wherein any one or more of solar radiation, precipitation, snowfall, snowfall, temperature, and humidity are used as the information on weather and weather conditions. 16. The fuel cell system according to claim 1, wherein one or more of the power load prediction devices according to claim 7 is used.