JP2011171010A - Fuel battery system and method for controlling fuel battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fuel battery system that can fully charge a power storage device in a state that power generation efficiency of the fuel battery is high, and to provide a method for controlling the fuel battery. <P>SOLUTION: The fuel battery system includes: a fuel battery; a storage part that stores a charging history to the power storage device by the fuel battery; and an operation condition determination part that determines an operation condition of the fuel battery while the power storage device is being charged based on a charge request power amount and the charging history. The method for controlling the fuel battery includes: a storage step of storing the charging history to power storage device by the fuel battery; and an operation condition determination step of determining the operation condition of the fuel battery while the power storage device is being charged based on a charge request power amount and the charging history. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a fuel cell system and a fuel cell control method.

  A fuel cell is a device that generally obtains electric energy using hydrogen and oxygen as fuel. Since this fuel cell is excellent in terms of the environment and can realize high energy efficiency, it has been widely developed as a future energy supply system.

  On the other hand, a system for charging a power storage device of a vehicle using a household power source has been developed. Attempts have been made to use a fuel cell as means for supplying power to the power storage device. For example, Patent Document 1 discloses a technique for charging a power storage device of a vehicle using electric power generated by a stationary fuel cell.

JP 2004-48895 A

  However, in the technique of Patent Document 1, since the power storage device is charged due to excessive generated power of the fuel cell, the power storage device may not be sufficiently charged. Further, it is not always possible to charge the power storage device in a state where the power generation efficiency of the fuel cell is high.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a fuel cell system and a fuel cell control method capable of charging a power storage device in a state where the power generation efficiency of the fuel cell is high.

  The fuel cell system according to the present invention includes a fuel cell, a storage unit that stores a charging history of the power storage device by the fuel cell, and a fuel at the time of charging the power storage device based on a required charge amount and a charging history of the power storage device. And an operating condition determining unit that determines operating conditions of the battery. According to the fuel cell system of the present invention, the power storage device can be charged in a state where the power generation efficiency of the fuel cell is high.

  The charge history may include a learning value of a chargeable time allowed for the user of the fuel cell to charge the power storage device. The chargeable time may be a time from charging plug-on to charging plug-off of the power storage device. The operating condition determination unit may determine the target charging power for the power storage device based on the charge required power amount of the power storage device and the learned value of the chargeable time. The target charging power may be power obtained by dividing the charging required power amount of the power storage device by the learning value of the chargeable time. The target charging power may be a product of a correction value and the power obtained by dividing the amount of power required for charging the power storage device by the learning value of the chargeable time.

  The operating condition determining unit may use the generated power of the fuel cell as the rated output when the sum of the target charging power and the required power of the electric load other than the power storage device is equal to or higher than the rated output of the fuel cell. When the sum of the target charging power and the required power of the electric load other than the power storage device is less than the rated output of the fuel cell, the operating condition determination unit determines the generated power of the fuel cell as the electric power other than the target charging power and the power storage device. You may set to the sum with the request | requirement electric power of load. The operating condition determination unit sets the generated power of the fuel cell to the minimum generated power when the sum of the target charging power and the required power of the electrical load other than the power storage device is less than the minimum generated power set for the fuel cell. May be.

  The charge history includes the required power amount required for the fuel cell from the electrical load other than the power storage device in the chargeable time, and the minimum generated power is the target charge power and the learned value of the required power amount as the learned value of the chargeable time. It may be the sum of the power obtained by dividing by. A grid linkage device that supplies power from a grid power source to a power storage device and / or a power load other than the power storage device when the sum of the target charging power and the required power of the electric load other than the power storage device is equal to or greater than the rated power generation of the fuel cell You may have. The power storage device may be a power storage device mounted on a vehicle as a vehicle driving power source.

  A fuel cell control method according to the present invention includes a storage step of storing a charging history of a power storage device by a fuel cell, a charging required power amount of the power storage device, and a charging history. An operation condition determining step for determining an operation condition. According to the fuel cell control method of the present invention, the power storage device can be charged in a state where the power generation efficiency of the fuel cell is high.

  The charge history may include a learning value of a chargeable time allowed for the user of the fuel cell to charge the power storage device. The chargeable time may be a time from charging plug-on to charging plug-off of the power storage device. In the operating condition determination step, the target charging power for the power storage device may be determined based on the charge required power amount of the power storage device and the learned value of the chargeable time. The target charging power may be power obtained by dividing the charging required power amount of the power storage device by the learning value of the chargeable time. The target charging power may be a product of a correction value and the power obtained by dividing the amount of power required for charging the power storage device by the learning value of the chargeable time.

  In the operation condition determination step, when the sum of the target charging power and the required power of the electric load other than the power storage device is equal to or higher than the rated output of the fuel cell, the generated power of the fuel cell may be set as the rated output. In the operating condition determination step, when the sum of the target charging power and the required power of the electric load other than the power storage device is less than the rated output of the fuel cell, the generated power of the fuel cell is converted into the electric power other than the target charging power and the power storage device. You may set to the sum with the request | requirement electric power of load. In the operating condition determination step, when the sum of the target charging power and the required power of the electrical load other than the power storage device is less than the minimum generated power set for the fuel cell, the generated power of the fuel cell is set to the minimum generated power May be.

  The charge history includes the required power amount required for the fuel cell from the electrical load other than the power storage device in the chargeable time, and the minimum generated power is the target charge power and the learned value of the required power amount as the learned value of the chargeable time. It may be the sum of the power obtained by dividing by. When the sum of the target charging power and the required power of the electrical load other than the power storage device is equal to or greater than the rated power generation power of the fuel cell, the system linkage step of supplying power from the power supply to the power storage device and / or a power load other than the power storage device May be included. The power storage device may be a power storage device mounted on a vehicle as a vehicle driving power source.

  ADVANTAGE OF THE INVENTION According to this invention, the fuel cell system which can fully charge an electrical storage apparatus in the state with the high electric power generation efficiency of a fuel cell, and the control method of a fuel cell can be provided.

1 is a block diagram illustrating an overall configuration of a system including a fuel cell system according to Embodiment 1. FIG. It is a block diagram which shows the whole structure of a fuel cell apparatus. It is a fragmentary perspective view containing the cross section of a fuel cell. It is a figure which shows the relationship between the load of a fuel cell, and power generation efficiency. It is a figure which shows an example of transition of the required electric power of a general electric load. It is a figure which shows the relationship between the required electric power of a general electric load, and the rated output of a fuel cell. As a comparative example, it is a figure explaining the case where an electrical storage apparatus is charged without considering the charge log | history with respect to an electrical storage apparatus. It is a figure explaining the case where an electrical storage apparatus is charged according to the control which concerns on a present Example. It is a figure which shows the detailed flowchart of the control which concerns on a present Example. It is a figure which shows the flowchart performed in parallel with the flowchart of FIG.

  Hereinafter, the best mode for carrying out the present invention will be described.

  FIG. 1 is a block diagram illustrating an overall configuration of a charging system including a fuel cell system 100 according to the first embodiment. As shown in FIG. 1, the fuel cell system 100 includes a system linkage device 110, a fuel cell device 120, and a charging device 130. The fuel cell device 120 includes a control unit 10, a fuel cell 70, and the like.

  The system linkage device 110 is a device that switches electrical connection and disconnection among the fuel cell 70, the general electrical load 200, and the system power supply. The system power source is a household power source or the like supplied to each home, and may be a business power source or the like supplied to a store, a factory, or the like. The general electric load 200 is an electric load other than the power storage device 330 described later in each home, store, factory, or the like. The charging device 130 is a device that switches electrical connection and disconnection between the fuel cell 70 and the vehicle 300 via the charging plug 400.

  The vehicle 300 is an automobile or the like equipped with a power storage device as a vehicle driving power source, and includes a plug insertion port 310, a communication device 320, a power storage device 330, a remaining power storage sensor 340, and the like. The plug insertion port 310 is an insertion port for inserting the charging plug 400, and is electrically connected to the power storage device 330 via the communication device 320. The remaining power storage sensor 340 is a sensor that detects the remaining power rate of the power storage device 330.

  In the following description, it is assumed that the state in which the charging plug 400 is inserted into the plug insertion port 310 (the charging plug 400 is turned on) is the on state, and the charging plug 400 is removed from the plug insertion port 310 (charging) It is assumed that the state in which the plug 400 is turned off is an off state.

  An outline of the operation of the fuel cell system 100 will be described with reference to FIG. The control unit 10 acquires the required power of the general electrical load 200 via the system linkage device 110. Next, the control unit 10 determines the operating condition of the fuel cell 70 so that electric power corresponding to the required power is supplied from the fuel cell 70 to the general electric load 200. When the charging plug 400 is on, the detection result of the remaining power storage sensor 340 is transmitted from the communication device 320 to the control unit 10 via the charging plug 400. Thereby, the control unit 10 acquires the required charging power amount of the power storage device 330. The charge required power amount is, for example, the power amount obtained by subtracting the current charge amount from the maximum capacity of the power storage device 330, the charge amount set by the user of the vehicle 300, or the like.

  Control unit 10 controls charging device 130 so that electric power is supplied from fuel cell device 120 to power storage device 330 of vehicle 300 based on the amount of power required for charging power storage device 330. When the electric power required by the general electric load 200 and / or the charging power to the power storage device 330 is large, the control unit 10 supplies power to the general electric load 200 and / or the power storage device 330 from the fuel cell 70 and the system power supply. As described above, the system linkage device 110 is controlled.

  FIG. 2 is a block diagram showing the overall configuration of the fuel cell device 120. As shown in FIG. 2, the fuel cell device 120 includes a control unit 10, a raw fuel supply unit 20, a reforming water supply unit 30, an oxidant gas supply unit 40, a reformer 50, a combustion chamber 60, a fuel cell 70, And a heat exchanger 80.

  The control unit 10 includes a CPU (Central Processing Unit), ROM (Read Only Memory), RAM (Random Access Memory), and the like, and includes a CPU 11, a timer 12, a storage unit 13, and the like. The timer 12 gives the CPU 11 information about time and time. The storage unit 13 stores variables, learning values, and the like that the CPU 11 uses for calculation. The timer 12 may be a function realized by the CPU 11 executing a predetermined program.

  The raw fuel supply unit 20 includes a fuel pump for supplying raw fuel such as hydrocarbons to the reformer 50. The reforming water supply unit 30 stores reforming water 31 that stores reforming water necessary for the steam reforming reaction in the reformer 50, and the reforming water stored in the reforming water tank 31 is supplied to the reformer 50. A reforming water pump 32 and the like for supply are included. The oxidant gas supply unit 40 includes an air pump for supplying an oxidant gas such as air to the cathode 71 of the fuel cell 70. The reformer 50 includes a vaporization unit 51 for vaporizing reformed water and a reforming unit 52 for generating fuel gas by a steam reforming reaction. The fuel cell 70 has a structure in which an electrolyte 73 is sandwiched between a cathode 71 and an anode 72.

  FIG. 3 is a partial perspective view including a cross section of the fuel cell 70. As shown in FIG. 3, the fuel cell 70 has a flat plate-like overall shape. A plurality of fuel gas passages 22 penetrating along the axial direction (longitudinal direction) are formed in the conductive support 21 having gas permeability. A fuel electrode 23, a solid electrolyte 24, and an oxygen electrode 25 are laminated in this order on one plane on the outer peripheral surface of the conductive support 21. On the other plane facing the oxygen electrode 25, an interconnector 27 is provided via a bonding layer 26, and a P-type semiconductor layer 28 for reducing contact resistance is provided thereon. The fuel electrode 23 functions as the anode 72 in FIG. 2, the oxygen electrode 25 functions as the cathode 71 in FIG. 2, and the solid electrolyte 24 functions as the electrolyte 73 in FIG. The fuel cell 70 may have a stack structure in which a plurality of single cells shown in FIG. 3 are stacked.

By supplying the reformed gas containing hydrogen to the fuel gas passage 22, hydrogen is supplied to the fuel electrode 23. On the other hand, oxygen is supplied to the oxygen electrode 25 by supplying an oxidant gas containing oxygen around the fuel cell 70. As a result, the following electrode reactions occur in the oxygen electrode 25 and the fuel electrode 23 to generate power. The power generation reaction is performed at 600 ° C. to 1000 ° C., for example.
Oxygen electrode: 1 / 2O ₂ + 2e ⁻ → O ²⁻ (solid electrolyte)
Fuel electrode: O ²⁻ (solid electrolyte) + H ₂ → H ₂ O + 2e ⁻

The material of the oxygen electrode 25 has oxidation resistance and is porous so that gaseous oxygen can reach the interface with the solid electrolyte 24. The solid electrolyte 24 has a function of moving oxygen ions O ²⁻ from the oxygen electrode 25 to the fuel electrode 23. The solid electrolyte 24 is composed of an oxygen ion conductive oxide. Further, the solid electrolyte 24 physically isolates the fuel gas and the oxidant gas, so that it is stable and dense in the oxidizing / reducing atmosphere. The fuel electrode 23 is made of a material that is stable in a reducing atmosphere and has an affinity for hydrogen. The interconnector 27 is provided to electrically connect the fuel cells 70 in series, and is dense to physically separate the fuel gas and the oxidant gas.

For example, the oxygen electrode 25 is formed of a lanthanum cobaltite-based perovskite complex oxide having high conductivity of both electrons and ions. The solid electrolyte 24 is formed of ZrO ₂ (YSZ) containing Y ₂ O ₃ having high ionic conductivity. The fuel electrode 23 is formed of a mixture of Ni having high electronic conductivity and ZrO ₂ (YSZ) containing Y ₂ O ₃ . The interconnector 27 is made of LaCrO ₃ or the like that has a high electronic conductivity and in which an alkaline earth oxide is dissolved. These materials are preferably close in thermal expansion coefficient.

  Next, an outline of the operation of the fuel cell device 120 during power generation will be described with reference to FIG. The raw fuel supply unit 20 supplies a required amount of raw fuel gas to the reformer 50 in accordance with instructions from the control unit 10. The reforming water pump 32 supplies a necessary amount of reforming water to the reformer 50 in accordance with instructions from the control unit 10. The fuel gas generated in the reformer 50 is supplied to the anode 72 of the fuel cell 70.

  The oxidant gas supply unit 40 supplies a necessary amount of oxidant gas to the cathode 71 of the fuel cell 70 in accordance with instructions from the control unit 10. Thereby, power generation is performed in the fuel cell 70. The oxidant off-gas discharged from the cathode 71 and the fuel off-gas discharged from the anode 72 flow into the combustion chamber 60. In the combustion chamber 60, the fuel off-gas burns with oxygen in the oxidant off-gas. The heat obtained by the combustion is given to the reformer 50 and the fuel cell 70. As described above, in the fuel cell device 120, combustible components such as hydrogen and carbon monoxide contained in the fuel off-gas can be burned in the combustion chamber 60. The heat exchanger 80 exchanges heat between the exhaust gas discharged from the combustion chamber 60 and tap water flowing in the heat exchanger 80. Condensed water obtained from the exhaust gas by heat exchange is stored in the reformed water tank 31.

  Here, the power generation efficiency of the fuel cell 70 will be described. FIG. 4 is a diagram showing the relationship between the load of the fuel cell 70 and the power generation efficiency. In FIG. 4, the horizontal axis indicates the load of the fuel cell 70, and the vertical axis indicates the power generation efficiency of the fuel cell 70. As shown in FIG. 4, the fuel cell 70 maintains high power generation efficiency from a rated load to a predetermined load (for example, about half of the rated load). However, when the load is equal to or lower than the predetermined load, the power generation efficiency rapidly decreases. Therefore, from the viewpoint of power generation efficiency, the fuel cell 70 preferably maintains a high load operation.

  Here, in the case where reverse power flow from the fuel cell 70 to the system power supply is prohibited, the fuel cell 70 cannot be made to generate power exceeding the power demand. Therefore, when the power required for the fuel cell 70 is small, the fuel cell 70 has to generate power with low power generation efficiency.

  FIG. 5 is a diagram illustrating an example of the transition of the required power of the general electric load 200 in the home. In FIG. 5, the horizontal axis indicates time, and the vertical axis indicates required power. As shown in FIG. 5, for example, the required power increases for a while after the evening, decreases from midnight to the next morning, and increases around the wake-up time. In this way, the required power is not constant and changes with time. The fuel cell device 120 causes the fuel cell 70 to generate power so as to follow the required power of the general electric load 200. Therefore, the power generation efficiency of the fuel cell 70 also changes according to the change in the required power of the general electric load 200.

  FIG. 6 is a diagram showing the relationship between the required power of the general electric load 200 and the rated output (rated generated power) of the fuel cell 70. In FIG. 6, the horizontal axis represents time, and the vertical axis represents the required power of the general electric load 200. As shown in FIG. 6, the required power of the general electric load 200 may temporarily exceed the rated output of the fuel cell 70. In this case, the electric power supplied to the general electric load 200 is insufficient. Therefore, the control unit 10 controls the system linkage device 110 so that power is supplied from the system power supply to the general electric load 200. Thereby, power shortage in the general electric load 200 is suppressed.

  Next, a case where the power storage device 330 of the vehicle 300 is charged using the power generated by the fuel cell 70 will be described. FIGS. 7A to 7C are diagrams illustrating a case where the power storage device 330 is charged without considering the charging history of the power storage device 330 as a comparative example. The vertical axis in FIG. 7A indicates the power generation efficiency of the fuel cell 70. The vertical axis in FIG. 7B indicates the required power of the general electric load 200 and the generated power of the fuel cell 70. In FIG. 7C, the vertical axis indicates the charge amount of the power storage device 330. The horizontal axis of Fig.7 (a)-FIG.7 (c) shows time.

  As shown in FIG. 7B, the generated power of the fuel cell 70 changes according to the required power of the general electric load 200, and therefore changes with time. The fuel cell 70 generates power so as to follow the required power of the general electric load 200. When charging plug 400 is turned on during a time period when general electric load 200 is relatively large, the sum of the required power of general electric load 200 and the required power of power storage device 330 exceeds the rated output of fuel cell 70. Thereby, the fuel cell 70 performs rated operation. Thereby, the fuel cell 70 generates power with high power generation efficiency. However, when the charging of the power storage device 330 is completed, the power required for the fuel cell 70 is only the power required for the general electric load 200. Therefore, the power generated by the fuel cell 70 is reduced, and the power generation efficiency of the fuel cell 70 is accordingly reduced. Decreases.

  As described above, in the control of FIGS. 7A to 7C, since the period during which the on state of the charging plug 400 is continued is not predicted, the control is concentrated on the first period of the on state of the charging plug 400. Thus, the power storage device 330 is charged. In this case, if the required power of the general electric load 200 decreases after the charging of the power storage device 330 is completed, the power generation efficiency of the fuel cell 70 becomes very low. Thereby, the period during which the fuel cell 70 generates power with low power generation efficiency becomes long.

  Therefore, in the present embodiment, the operating condition of the fuel cell 70 at the time of charging the power storage device 330 is determined based on the required amount of charge of the power storage device 330 and the charging history of the power storage device 330. In the present embodiment, the control unit 10 functions as an operating condition determination unit.

  The charge history includes, for example, a learning value of a chargeable time allowed for the user of the fuel cell 70 to charge the power storage device 330. The chargeable time allowed by the user is, for example, a period from when the user inserts the charging plug 400 into the plug insertion port 310 until removal. That is, the chargeable time allowed by the user is a period during which the user desires the power storage device 330 to be fully charged. For example, this corresponds to a period during which the user parks the vehicle 300 at home. Hereinafter, specific control by the control unit 10 will be described. The following control is realized, for example, when the CPU 11 of the control unit 10 executes a predetermined program.

  First, when the charging plug 400 is turned on, the control unit 10 controls the charging device 130 to wait for charging from the fuel cell device 120 to the power storage device 330. Next, based on the detection result of the remaining power storage sensor 340, the control unit 10 obtains the required charging power amount PHV_req of the power storage device 330. Control unit 10 obtains learning value T_fb of the chargeable time of power storage device 330 from storage unit 13. Here, the learning value T_fb of the chargeable time is a learning value based on the past history of the time from the time when the charging plug 400 is turned on to the time when it is turned off. Next, the control unit 10 acquires a learning value P_e of the required power amount of the general electric load 200 from the storage unit 13. Here, the learning value P_e of the required electric energy of the general electric load 200 is a learning value based on the past history of the required electric energy of the general electric load 200 within the chargeable time of the power storage device 330.

The control unit 10 calculates the generated power P_fc of the fuel cell 70 according to the following equation (1) based on the required charging power amount PHV_req, the learned value T_fb, and the learned value P_e. Note that “k” in the equation is a correction coefficient for adjusting the difference between the learning result and the actual value, and can be set to, for example, about “1.1”.
P_fc = k × ((PHV_req + P_e) / T_fb) (1)

  The control unit 10 employs the larger one of the generated power P_fc obtained by the above formula (1) and the minimum generated power P_fc_lmt of the fuel cell 70 as the output of the fuel cell 70. Thereby, it is suppressed that the electric power generation efficiency of the fuel cell 70 falls excessively. Here, the minimum generated power P_fc_lmt is the minimum output at which the fuel cell 70 can maintain a predetermined power generation efficiency. For example, the minimum generated power P_fc_lmt can be about the rated generated power P_fc_max × 0.7 of the fuel cell 70.

  Further, the control unit 10 employs the smaller one of the generated power P_fc obtained by the above formula (1) and the rated generated power P_fc_max of the fuel cell 70 as the output of the fuel cell 70. This suppresses the fuel cell 70 from generating excessive power. However, when the demand power of the general electric load 200 and the power storage device 330 exceeds the generated power P_fc, the control unit 10 controls the output of the fuel cell 70 below the rated generated power P_fc_max.

  FIG. 8A to FIG. 8C are diagrams illustrating a case where the power storage device 330 is charged according to the above control. The vertical axis in FIG. 8A indicates the power generation efficiency of the fuel cell 70. The vertical axis in FIG. 8B indicates the required power of the general electric load 200 and the generated power of the fuel cell 70. The vertical axis in FIG. 8C indicates the amount of charge of the power storage device 330. The horizontal axis of Fig.8 (a)-FIG.8 (c) shows time.

  As shown in FIG. 8B, even when the charging plug 400 is turned on, the fuel cell 70 does not perform the rated operation. Further, as illustrated in FIG. 8C, the power storage device 330 is gradually charged over a time close to the chargeable time of the power storage device 330 obtained as the learning value. Thereby, the fuel cell 70 continues power generation with relatively high power generation efficiency over a long period of time. Thereby, the power generation period with low power generation efficiency can be shortened. From the above, the power storage device 330 can be sufficiently charged, and the power storage device 330 can be charged in a state where the power generation efficiency of the fuel cell 70 is high. Further, as shown in FIG. 8B, when the required power of the general electric load 200 is large, the fuel cell 70 performs power generation following the required power. Therefore, power shortage is suppressed.

  FIG. 9 is a diagram showing a more detailed flowchart of the control. In the flowchart of FIG. 9, learning of the chargeable time and the required power amount required from the general electric load 200 during the chargeable time are shown. Further, the target charging power to the power storage device 330 is shown. Hereinafter, more detailed control will be described with reference to the flowchart of FIG.

  First, the CPU 11 determines whether or not the charging plug 400 has changed from an on state to an off state (step S1). When it is determined as “Yes” in Step S1, the CPU 11 reads the charging end time T_stp from the timer 12 (Step S2). Next, the CPU 11 obtains a chargeable time T_itv by subtracting the charge start time T_str from the charge end time T_stp (step S3). The charging start time T_str is read in step S11 described later.

  Next, the CPU 11 determines whether or not the chargeable time learning value T_fb stored in the storage unit 13 is greater than the sum of the chargeable time T_itv and the learning value update determination time T_err (step S4). Steps S4 to S8 are processes for correcting the learned value T_fb with the actual chargeable time T_itv. The learning value update determination time T_err can be set to about 1 minute, for example.

  When it is determined as “Yes” in step S4, the CPU 11 decreases the learning value T_fb by the update gain dT_fb (step S5). The update gain dT_fb can be set to about 1 minute, for example. When it is determined as “No” in Step S4, the CPU 11 determines whether or not the learning value T_fb is smaller than a value obtained by subtracting the learning value update determination time T_err from the chargeable time T_itv (Step S6).

  When it is determined “No” in step S6, the CPU 11 ends the execution of the flowchart. In this case, the learning value T_fb is not updated and is maintained at the current value. When it is determined as “Yes” in Step S6, the CPU 11 increases the learning value T_fb by the update gain dT_fb (Step S7). After step S5 or step S7 is executed, the CPU 11 multiplies the learned value T_fb by the slip rate SLP to obtain the final learned value T_fb and stores it in the storage unit 13 (step S8). The slip ratio SLP is a slip ratio that may occur between the updated learned value T_fb and the next actual chargeable time T_itv, and is about 0.9, for example.

  By performing the above steps S4 to S8, a learning value of the chargeable time can be obtained. Note that the process of obtaining the learning value of the chargeable time is not limited to the above. For example, the learning value update determination time T_err may not be used in steps S4 and S6. Moreover, it is good also considering the time obtained by step S3 as a learning value of chargeable time.

  Next, the CPU 11 divides the required power amount P_e of the general electric load 200 in the chargeable time T_itv obtained last time by the learned value T_fb, thereby obtaining the learned value P_e_old of the required power of the general electric load 200 in the chargeable time. Is stored in the storage unit 13 (step S9). Thereafter, the CPU 11 ends the execution of the flowchart.

  When it is determined as “No” in Step S1, the CPU 11 determines whether or not the charging plug 400 is turned on from the off state (Step S10). When it determines with "Yes" at step S10, CPU11 reads charge start time T_str from the timer 12 (step S11). Next, the CPU 11 obtains, as the required power amount P_e, a value obtained by adding the integrated value P_e of the required power of the general electric load 200 obtained at the previous execution of the flowchart and the current required power P_e of the general electric load 200. (Step S12) By repeating this step S12, the required power amount P_e of the general electric load 200 during the period corresponding to the chargeable time T_itv can be obtained. When it determines with "No" in step S10, CPU performs step S12, without performing step S11.

Next, the CPU 11 reads the remaining charge rate SOC of the power storage device 330 from the remaining charge sensor 340 (step S13). Next, the CPU 11 obtains the target charging power P_v per unit time from the maximum capacity P_v_max of the power storage device 330, the remaining power storage rate SOC, and the learned value T_fb according to the following equation (2) (step S14). (P_v_max × (1-SOC)) in the following formula (2) corresponds to the required charging power amount of the power storage device 330. The power obtained by multiplying the result obtained by the following formula (2) by a correction value (for example, “0.9”, “1.1”, etc.) may be used as the target charging power.
P_v = (P_v_max × (1-SOC)) / T_fb (2)

Next, the CPU 11 sets the appropriate generated power P_fc_set of the fuel cell 70 to the rated generated power P_fc_max when the following expression (3) is satisfied, and sets the appropriate generated power P_fc_set when the following expression (4) is satisfied. The sum of the learned value P_e_old and the target charging power P_v is set, and when the following equation (5) is satisfied, the appropriate generated power P_fc_set is set to the minimum appropriate generated power P_fc_lmt of the fuel cell 70 (step S15). Thereafter, the CPU 11 ends the execution of the flowchart. Note that the minimum appropriate generated power P_fc_lmt can be a value that is about 30% less than the rated generated power P_fc_max.
P_fc_max ≦ P_e_old + P_v (3)
P_fc_max> P_e_old + P_v> P_fc_lmt (4)
P_fc_lmt ≦ P_e_old + P_v (5)

  The CPU 11 executes the flowchart of FIG. 10 in parallel with the flowchart of FIG. First, the CPU 11 determines whether or not the charging plug 400 is in an on state (step S21). By executing step S21, it is possible to determine whether or not charging of the power storage device 330 is requested. When it determines with "Yes" in step S21, CPU11 determines whether the electrical storage residual amount rate SOC obtained from the electrical storage residual amount sensor 340 is less than 1.0 (step S22). By performing step S <b> 22, it can be determined whether charging of the power storage device 330 has been completed.

When it is determined as “Yes” in step S22, the CPU 11 sets the generated power P_fc of the fuel cell 70 to the rated generated power P_fc_max when the following formula (6) is satisfied, and the following formula (7) is satisfied. In this case, the generated power P_fc is set to the sum of the required power P_e of the current general electric load 200 and the target charging power P_v. Is set to the appropriate generated power P_fc_set (step S23). Thereafter, the CPU 11 ends the execution of the flowchart.
P_fc_max ≦ ([current P_e] + P_v) (6)
P_fc_max> ([current P_e] + P_v)> P_fc_set (7)
P_fc_set> ([current P_e] + P_v) (8)

  According to the flowcharts of FIGS. 9 and 10, the learning value of the chargeable time of the power storage device 330 can be obtained. Moreover, the required electric energy requested | required from the general electric load 200 in the chargeable time can be obtained. Further, the target charging power for the power storage device 330 can be obtained. Based on the obtained target charging power, appropriate generated power of the fuel cell 70 can be obtained. As a result, the power storage device 330 can be sufficiently charged, and the power storage device 330 can be charged with the power generation efficiency of the fuel cell 70 being high.

  The above embodiment can be applied to any other type of fuel cell such as a solid polymer type, a solid oxide type, and a carbonated molten salt type. However, since the solid oxide fuel cell is a thermoautonomous fuel cell, the effect of using the fuel cell system 100 according to the present embodiment is great in that it requires a certain amount of heat supply at a low power generation load. Become.

DESCRIPTION OF SYMBOLS 10 Control part 70 Fuel cell 100 Fuel cell system 110 Grid cooperation apparatus 120 Fuel cell apparatus 130 Charging apparatus 200 General electric load 300 Vehicle 310 Plug insertion slot 320 Communication apparatus 330 Power storage apparatus 340 Charge amount sensor 400 Charge plug

Claims (24)

A fuel cell;
A storage unit for storing a charging history of the power storage device by the fuel cell;
A fuel cell system comprising: an operation condition determining unit that determines an operation condition of the fuel cell at the time of charging the power storage device based on a required charging power amount of the power storage device and the charging history.   2. The fuel cell system according to claim 1, wherein the charge history includes a learning value of a chargeable time allowed for charging of the power storage device by a user of the fuel cell.   The fuel cell system according to claim 2, wherein the chargeable time is a time from a charge plug-on to a charge plug-off of the power storage device.   The said operation condition determination part determines the target charging electric power to the said electrical storage apparatus based on the charging required electric energy of the said electrical storage apparatus, and the learning value of the said chargeable time. Fuel cell system.   5. The fuel cell system according to claim 4, wherein the target charging power is power obtained by dividing a required charging power amount of the power storage device by a learning value of the chargeable time.   5. The fuel cell according to claim 4, wherein the target charging power is a product of a correction value and a power obtained by dividing a charging required power amount of the power storage device by a learning value of the chargeable time. system.   The operating condition determining unit sets the generated power of the fuel cell as a rated output when the sum of the target charging power and the required power of an electrical load other than the power storage device is equal to or higher than the rated output of the fuel cell. A fuel cell system according to any one of claims 4 to 6.   The operating condition determining unit determines the generated power of the fuel cell as the target charging power when the sum of the target charging power and the required power of an electrical load other than the power storage device is less than a rated output of the fuel cell. The fuel cell system according to any one of claims 4 to 6, wherein the fuel cell system is set to a sum of the required power of an electrical load other than the power storage device.   When the sum of the target charging power and the required power of an electrical load other than the power storage device is less than the minimum generated power set in the fuel cell, the operating condition determining unit determines the generated power of the fuel cell, The fuel cell system according to any one of claims 4 to 6, wherein the minimum generated power is set. The charge history includes a required power amount required for the fuel cell from an electric load other than the power storage device in the chargeable time,
10. The fuel cell system according to claim 9, wherein the minimum generated power is a sum of the target charging power and power obtained by dividing the required power amount by a learning value of the chargeable time. .   When the sum of the target charging power and the required power of the electrical load other than the power storage device is equal to or higher than the rated power generation of the fuel cell, power is supplied from the system power supply to the power storage device and / or a power load other than the power storage device The fuel cell system according to claim 7, further comprising a system linkage device that performs the operation.   The fuel cell system according to claim 1, wherein the power storage device is a power storage device mounted on a vehicle as a vehicle driving power source. A storage step of storing a charging history of the power storage device by the fuel cell;
A fuel cell control comprising: an operating condition determining step for determining an operating condition of the fuel cell when charging the power storage device based on a required charging power amount of the power storage device and the charging history. Method.   The fuel cell control method according to claim 13, wherein the charge history includes a learned value of a chargeable time allowed by the user of the fuel cell to charge the power storage device.   14. The fuel cell control method according to claim 13, wherein the chargeable time is a time from charge plug-on to charge plug-off of the power storage device.   16. The target charging power for the power storage device is determined in the operation condition determination step based on a required charging power amount of the power storage device and a learned value of the chargeable time. Fuel cell control method.   The fuel cell control method according to claim 16, wherein the target charging power is power obtained by dividing a required charging power amount of the power storage device by a learning value of the chargeable time.   17. The fuel cell according to claim 16, wherein the target charging power is a product of a power and a correction value obtained by dividing a charging required power amount of the power storage device by a learning value of the chargeable time. Control method.   In the operation condition determining step, when the sum of the target charging power and the required power of an electric load other than the power storage device is equal to or higher than a rated output of the fuel cell, the generated power of the fuel cell is set as a rated output. The method for controlling a fuel cell according to any one of claims 16 to 18.   In the operating condition determination step, when the sum of the target charging power and the required power of an electric load other than the power storage device is less than the rated output of the fuel cell, the generated power of the fuel cell is converted to the target charging power. The fuel cell control method according to any one of claims 16 to 18, wherein the sum is set to the sum of the required power of an electrical load other than the power storage device.   In the operating condition determination step, when the sum of the target charging power and the required power of the electric load other than the power storage device is less than the minimum generated power set in the fuel cell, the generated power of the fuel cell is The fuel cell control method according to any one of claims 16 to 18, wherein the minimum generated power is set. The charge history includes a required power amount required for the fuel cell from an electric load other than the power storage device in the chargeable time,
The fuel cell according to claim 21, wherein the minimum generated power is a sum of the target charging power and power obtained by dividing the required power amount by a learning value of the chargeable time. Control method.   When the sum of the target charging power and the required power of the electrical load other than the power storage device is equal to or higher than the rated power generation of the fuel cell, power is supplied from the system power supply to the power storage device and / or a power load other than the power storage device The fuel cell control method according to claim 19, further comprising a system linkage step.   The fuel cell control method according to any one of claims 13 to 23, wherein the power storage device is a power storage device mounted on a vehicle as a vehicle driving power source.

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