JP5502299B2 - Fuel cell system - Google Patents

Description

  The present invention relates to a fuel cell system suitable for power supply.

  In a conventional household fuel cell system, for example, as shown in FIG. 6, an operation method is adopted in which a household power demand is measured in real time and the fuel cell is controlled so that the amount of power supply follows that value. Yes.

  In a fuel cell system that employs such an operation method, the power output of the fuel cell is loaded with electric equipment that consumes a lot of electricity, such as hair dryers, microwave ovens, toasters, etc. In the case of the follow-up, the power generation output sharply rises at the same time as the use of the electric device starts, and the power generation output sharply decreases at the same time as the use of the electric device ends.

  However, if such a steep increase in power generation output or a sharp decrease in power generation output is performed by control of the fuel cell, it will affect the life of the fuel cell. In addition, as shown in FIG. 7, when the electric power demand is suddenly reduced at the end of use of the electric device described above, and when the output reduction of the fuel cell cannot follow this, surplus power is generated in the fuel cell. This surplus power is generally consumed by reverse power flow to the power system or by warming hot water with a heater or the like.

  In addition, if surplus power is reversely flowed to the power system, it becomes one of the factors that cause the system to become unstable, and heating of hot water by the heater causes deviation from the hot water supply plan of the fuel cell system. The so-called surplus hot water is left in the tank.

Therefore, recently, the change in power demand is characterized for each time zone, the rate of change when power generation output rises and power generation output decreases, the waste of time from receiving the output control signal to outputting the drive signal to perform control There is a setting for setting a deviation (offset) to be subtracted from time (waiting time) and electric power used in each time zone so as not to follow even if the power demand changes rapidly (Cited document 1).
JP 2002-291116 A

  However, it has been difficult for the above-described conventional fuel cell power generation apparatus to adapt to the power consumption load for each household. That is, in the case of the technique of Patent Document 1, since the change rate, dead time, and offset that should be set in advance are originally different for each home, it is difficult to calculate an optimum value for each home. Furthermore, it is difficult to cope with cases where the usage status of the device changes due to seasonal changes or lifestyle changes, and the power consumption changes greatly.

  The present invention has been made in view of the circumstances as described above, and is a fuel that can prevent or reduce reverse power flow, excess hot water, and a decrease in service life to an electric power system regardless of the use time and use time of an electric device. An object is to provide a battery system.

  In order to achieve the above object, the present invention configures a fuel cell system by the following means.

(1) The present invention provides a fuel cell that outputs generated power and supplies electricity and hot water to an installation site, power demand measuring means for measuring power consumption at the installation site of the fuel cell, and power demand measurement Demand data storage means for storing power demand data measured by the means, electrical equipment data storage means for storing various data relating to electrical equipment in advance, power demand data stored in the demand data storage means, against the data stored in the electric equipment data storage unit, the user and the used electric device identifying means for identifying electrical equipment at the time was started with or used used, it was identified in this use electrical equipment identifying means electrically Power generation output control means for controlling the power generation output of the fuel cell based on data corresponding to the device.

(2) In the present invention, in addition to the configuration of the above (1), how the electric device identified by the used electric device identification unit is used is stored in the electric device data storage unit. An electrical device usage pattern predicting unit that predicts using data is provided, and the power generation output control unit generates power from the fuel cell based on data relating to the usage method of the electrical device predicted by the electrical device usage pattern prediction unit. Control the output.

  According to the present invention, it is possible to prevent or reduce reverse power flow to the electric power system, remaining hot water, and a decrease in service life regardless of the use time and use time of the electrical equipment.

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

  FIG. 1 is a block diagram showing a basic configuration of a fuel cell system to which the present invention is applied.

  In FIG. 1, 101 is a fuel control means for controlling fuel such as city gas, LP gas and kerosene, and 102 is a reforming means for reforming the fuel supplied and controlled by the fuel control means 101 to a hydrogen rich gas. , 103 is a fuel cell body that generates direct-current power by reacting hydrogen in the reformed gas with oxygen in the air when the hydrogen-rich gas reformed by the reforming means 102 is supplied. The fuel control means 101, the reforming means 102, the fuel cell main body 103, and the inverter 104 are inverters that convert DC power generated by the battery main body 103 into AC power having a predetermined frequency and supply it to the household power load 120. The fuel cell power generation device FC is configured.

  On the other hand, 105 is an operation plan formulating means for making an operation plan related to the output of the fuel cell power generation device FC, 106 is an operation plan established by the operation plan formulating means 105 and power information supplied from the inverter 104 to the household power load 120. This is an operation control means that takes in the electric power, calculates electric power to be output instantaneously, and gives a control command to the fuel control means 101.

  Here, the value calculated by the operation control means 106 is the output itself of the operation plan formulated for each time zone, and the power output from the inverter 104 by the household power load 120. In order to avoid the above, there are cases where the output is lower than the output of the operation plan and the household electric power load 120 is caused to follow the load.

  FIG. 2 is a block diagram showing a first embodiment of the fuel cell system according to the present invention.

  If the fuel cell generator FC is in load following operation at the time when the use of an electric device such as a dryer, microwave oven, toaster, etc. is started as a household power load, the surplus power is consumed at the same time as the use of the electric device is finished. Is likely to occur.

Therefore, in the first embodiment, the operation control means 106 identifies an electric device that has begun to be used at home from the power information consumed by the household power load 120, and the electric device has the above characteristics. If so, the load following operation of the fuel cell power generator is temporarily canceled.

2, power demand measuring means 1, a power demand to be supplied to the load from the fuel cell power generation system FC is measured in real time, the power demand measured by the power demand measurement hand stage 1, demand data storage Accumulated in the means 2.

  On the other hand, the electrical device data storage means 4 stores data such as average usage time and power consumption for each electrical device in advance. Data stored in the electrical device data storage means 4 (for example, power consumption, model number, manufacturer name, etc.) may be directly registered by the user, or only the electrical device used by the user is registered. Information on the information may be acquired through the Internet or the like.

In addition, the used electric equipment identifying means 5 compares the electric power demand data stored in the demand data storage means 2 with the data stored in the electric equipment data storage means 4 to determine the electric equipment that the user has started to use. Identify . Actually, among the data stored in the demand data storage means 2, the sudden increase in power demand from about several seconds ago and the power consumption for each electrical device stored in the electrical equipment data storage means 4 Identify by checking.

In this case, the identification of the electrical equipment, it is sufficient identification, such as home appliances A, it is not necessary to identify the electrical equipment such as "dryer".

Furthermore, the electric equipment usage pattern predicting means 6 predicts how the electric equipment identified by the used electric equipment identifying means 5 will be used by using the data stored in the electric equipment data storing means 4. .

  Further, the power generation output control means 7 controls the power generation output of the fuel cell power generation device (FC) 8 based on the data related to the usage method of the electric equipment predicted by the electric equipment usage pattern prediction means 6. For example, when it is predicted that an electric device that consumes a large amount of power and has a short usage time will be used, control is performed such that the power generation output is not increased in accordance with the power demand.

  Here, a case immediately after starting to use a 1500 W dryer at home will be described in detail.

  It is assumed that the power demand data for the past one second measured by the power demand measuring means 1 and stored in the demand data accumulating means 2 is that the power demand at home has increased by about 1500 W. In this case, the amount of increase in power demand can be 1400 W, 1600 W, or the like, depending on the usage status of other electrical devices.

In the used electric equipment identifying means 5, the electric equipment B that has started to be used is compared with the information in Table 1 stored in the electric equipment data storage means 4 and the above increase in power demand. Identify .

Further, in the electrical equipment usage pattern predicting means 6, the usage time of the electrical equipment B identified by the used electrical equipment identifying means 5 based on the information in Table 2 stored in the electrical equipment data storage means 4 is 5 to 5. Get information that it is 10 minutes.

  Therefore, since the power generation output control means 7 has a short usage time prediction of 5 to 10 minutes in the electrical equipment usage pattern prediction means 6, the power generation output control means 7 will meet the power demand until the power demand is reduced by 1300 to 1700 W / s. The fuel cell power generator (FC) 8 is controlled so as to keep the generated power constant without following the load.

  However, when the usage time of the electric device B is longer than 30 minutes, the load following operation is continued. In addition, even if the load follow-up operation is stopped because the prediction of the usage time is as short as 5 to 10 minutes, the load follow-up operation is resumed if the decrease in power demand is not observed even after 10 minutes or more. Return.

  The above is an example of the present invention and does not limit the present invention. For example, the electrical device that has started to be used is identified based on the amount of change in power demand in the past one second, but may be a shorter amount of change in the past 0.5 seconds. As a criterion for determining whether or not to follow the load, the usage time of the electric device is 30 minutes, but this may be another time length such as one hour.

As described above, in the first embodiment, the power demand measuring unit 1 always measures the amount of power demand supplied from the fuel cell power generation device 8 to the household load and accumulates it in the demand data accumulating unit 2 to identify the electric equipment used. The power demand data stored in the demand data storage means 2 by the means 5 is compared with the data stored in the electrical equipment data storage means 4 to identify the electrical equipment that the user has started to use and use the electrical equipment or electrical device identified by using electric device identification means 5 is how they are used by the embodiment predicting unit 6 predicts using the data stored in the electric equipment data storage unit 4, the use of the electrical device Since the power generation output of the fuel cell power generation device 8 is controlled based on the data on the method, the power generation output of the fuel cell power generation device can be obtained even immediately after the end of the use of the electric device having the characteristics. By previously controlling low, it is possible to avoid the occurrence of excess power. Thereby, the reverse power flow of surplus electric power, the remaining hot water, and the lifetime reduction of a fuel cell can be avoided.

  FIG. 3 is a block diagram showing a second embodiment of the fuel cell system according to the present invention. The same functional parts as those in FIG.

In the second embodiment, the electric power demand measuring means 1 and the hot water demand measuring means 11 are provided to measure both the electric power demand and the hot water demand, and the electric equipment that the user has started to use using these two demand patterns. The output of the fuel cell power generation device (FC) 8 is identified and controlled.

  Here, the demand data storage means 2 stores hot water demand data in addition to the power demand data, and the electrical equipment data storage means 4 stores hot water demand data in addition to the power demand data. Yes.

  Due to the nature of electrical equipment such as hair dryers, hot water is often used before use as a household power load. Some electric devices use hot water at the same time as use, or use hot water after consuming electric power.

Therefore, by using both the power demand and the hot water demand, the identification accuracy of the used electric appliance identifying means 5 can be increased. As an example of this electrical device identification method, consider the case where, for example, the use of electrical device A and electrical device B is identified from the specific pattern of power demand described in the first embodiment. The electric equipment A has a specific hot water demand pattern in a certain time zone range before use, and the electric equipment B uses hot water simultaneously with electric power. These pieces of information are stored in the electric equipment data storage means 4. ing.

When there is no demand for hot water at the same time as the specific pattern of power demand and there is a specific pattern of hot water demand that matches the usage pattern of the electrical equipment A before the power demand pattern, the specific pattern of power demand is the electrical equipment. Can be identified as due to the use of A.

  Therefore, the power generation output control means 7 controls the fuel cell power generation device (FC) 8 based on the data regarding the usage method of the electric equipment predicted by the electric equipment usage pattern prediction means 6. For example, when it is predicted that an electric device with high power consumption and short usage time will be used, control is performed such that the power generation output is not increased in accordance with the power demand.

As described above, in the second embodiment, the demand data storage means 2 stores hot water demand data in addition to the power demand data, and the electrical equipment data storage means 4 stores data related to the demand for hot water in addition to the data related to the power demand. Since the electric appliance used is identified by the electric appliance identification means 5 using both the electric power demand and the hot water demand, the identification accuracy can be increased.

  FIG. 4 is a block diagram showing a third embodiment of the fuel cell system according to the present invention, and the same functional parts as those in FIG.

  In the third embodiment, the power demand amount stored in the demand data storage means 2 is input to the demand data calculation means 10 and calculated in order to cope with the increase / decrease in the electrical equipment used by the user and changes in the usage pattern. The data stored in the electrical device data storage means 4 is updated by the processing.

Further, with respect to electrical devices that are identified as being used in used electrical equipment identifying means 5, the electrical device using end determining unit 9 for determining an end of the electrical equipment used provided the electrical equipment used end determining unit 9, when the end of use of the electric device is determined by taking in the determination condition of the end of use of the electric device created by the electric device usage pattern predicting unit 6, the demand data calculating unit 10 and the power generation output control unit 7 To give to. In this case, the determination condition for the end of use of the electric device is, for example, a momentary decrease in power demand by a predetermined amount.

In the fuel cell system having such a configuration, when it is determined that the use of the electric device is ended by the electric device use end determination unit 9, the demand data calculation unit 10 stores the data of the demand data storage unit 2 from the start of use to the end of use. Arithmetic processing. For example, data on the relationship between the usage time of the electrical equipment and the demand for hot water is calculated. By reflecting or adding this calculation result to the electrical equipment data, the identification accuracy of the used electrical equipment identification means 5 can be increased.

  FIG. 5 is a block diagram showing a fourth embodiment of the fuel cell system according to the present invention. The same functional parts as those in FIG.

In the fourth embodiment, the specific electrical equipment use determining means 3 for setting the identification start condition of the used electrical equipment is provided for the demand data sent from the demand data accumulating means 2 to the used electrical equipment identifying means 5. The used electrical equipment is identified only when the demand data sent from the data storage means 2 satisfies the identification start condition of the used electrical equipment.

In this case, the identification start condition of the electric equipment used includes, for example, an increase in power demand of 500 W / s or more. Further, this identification start condition may be changed according to the information stored in the electrical equipment data storage unit 4.

Therefore, with such a configuration, it is possible to optimize the timing of identification in the used electric appliance identifying means 5 and reduce the burden on the arithmetic unit.

1 is a block diagram showing a basic configuration of a fuel cell system to which the present invention is applied. 1 is a block diagram showing a first embodiment of a fuel cell system according to the present invention. The block diagram which shows 2nd Embodiment of the fuel cell system by this invention. The block diagram which shows 3rd Embodiment of the fuel cell system by this invention. The block diagram which shows 4th Embodiment of the fuel cell system by this invention. The figure for demonstrating the time-dependent change of the electric power supply of the fuel cell system which performs load following with respect to electric power demand. The figure for demonstrating generation | occurrence | production of the surplus electric power similarly in a fuel cell system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Electric power demand measurement means, 2 ... Demand data storage means, 3 ... Specific electric equipment use determination means, 4 ... Electric equipment data storage means, 5 ... Used electric equipment identification means, 6 ... Electric equipment usage form prediction means, 7 ... Power generation output control means, 8 ... Fuel cell power generation device (FC), 9 ... Electric equipment use end determination means, 10 ... Demand data calculation means, 11 ... Hot water demand measurement means, 101 ... Fuel control means, 102 ... Reforming means, DESCRIPTION OF SYMBOLS 103 ... Fuel cell main body, 104 ... Inverter, 105 ... Operation plan formulation means, 106 ... Operation control means

Claims (4)

A fuel cell that outputs generated power and supplies electricity and hot water to the installation site;
Power demand measuring means for measuring the power consumption of the fuel cell installation site;
Demand data storage means for storing power demand data measured by the power demand measuring means;
Electrical equipment data storage means in which data relating to usage forms of electrical equipment is stored in advance;
Electric appliance identification used to identify an electric appliance that the user has started to use or is using by comparing the power demand data stored in the demand data storage means with the data stored in the electric equipment data storage means Means,
Power generation output control means for controlling the power generation output of the fuel cell based on the data corresponding to the electric equipment identified by the electric equipment identification means used;
A fuel cell system comprising: The fuel cell system according to claim 1, wherein
An electrical device usage pattern predicting unit that predicts how the electrical device identified by the used electrical device identification unit is used by using data stored in the electrical device data storage unit is provided,
The power generation output control means controls the power generation output of the fuel cell based on data relating to the usage method of the electric equipment predicted by the electric equipment usage pattern prediction means. The fuel cell system according to claim 1 or 2,
The electric device data storage means can register at least one of an electric device used by a user, information on the electric device, and a usage form of the electric device. The fuel cell system according to any one of claims 1 to 3,
The use electrical equipment identification means, the fuel cell system electric power demand and performs identification of the electrical device only when filled with predetermined identification start condition.

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