JP6093598B2 - Power supply system, power supply program, and power supply method - Google Patents

Description

The present invention relates to a power supply system, a power supply program, and a power supply method including a power generation unit such as a fuel cell cogeneration system (hereinafter simply referred to as “FC system”) and a power storage unit.

  In the FC system, power generation is performed according to the amount of power load at a demand destination such as a home, and the power generation output is supplied to the power load. The amount of power load is measured by a current sensor installed at a demand destination. This FC system mainly uses a system power supply to supply generated power to an electric load. The system power supply is commercial power supplied from an electric power company.

  The first reason for using the system power supply is to prevent reverse power flow. In the FC system, power generation is performed with electric power that is lower by several tens of watts than the electric power load, and electric power of about several tens of watts is always provided by system power. The reason for this is to prevent the power generated by the FC system from flowing back into the system even if the power load increases or decreases, if the FC system generates electric power as low as several tens of watts.

  The second is to secure a voltage source in the FC system. The FC system has a current type inverter. This current type inverter is effective for controlling the amount of generated current, but cannot generate power if the voltage source is lost. A voltage source is indispensable for an FC system using a current type inverter.

With respect to such an FC system, it is known that a power generation device is incorporated and power supply from the FC system to a load can be performed even when the system power supply is disconnected from the FC system, such as during a power failure (for example, patents). Reference 1).

JP 2012-044733 A

  By the way, when the system power supply is disconnected, the voltage source disappears from the FC system, and the FC system stops power generation. Therefore, if a storage battery is installed on the primary side of this FC system, this storage battery can be used as a voltage source, and the FC system can continue power generation even when the system power supply is disconnected. Thereby, it is possible to supply the generated power of the FC system to the power load at the time of power failure of the system power supply.

  And if a storage battery is charged with the power generation output of the FC system at the time of a power failure, a decrease in the amount of electricity stored at the time of the power failure can be suppressed, but there is a problem that power is lost depending on the amount of charge provided from the FC system.

  Even if the storage battery is charged from the FC system, if the power loss increases, the amount of electricity stored in the storage battery decreases, and the power supply time during a power failure is shortened. That is, if the charge amount of the storage battery is equal to or greater than the generated power of the FC system, the discharge amount from the storage battery increases. As a result, the power in these charge / discharge processes increases, and the power loss increases. Eventually, there is a problem that the power supply time is shortened during a power failure.

  On the other hand, if the amount of charge is less than the generated power of the FC system, charging is possible without increasing power loss. However, if the charge amount is considerably smaller than the FC system generated power, there is a problem that the amount of stored electricity is smaller than when charging in the vicinity of the FC system generated power, and the power supply time during a power failure is shortened.

  Further, even when the FC system is stopped after the charging operation of the storage battery, if the charging operation is continued, there is a problem that the power loss is increased, the amount of stored electricity is reduced, and the power supply time at the time of power failure is shortened.

  Therefore, the present invention has been made in view of the above problems, and a first object is to improve the continuity of power generation during a power failure.

The second object is to improve the continuity of power generation during a power failure even when the power generation means includes an FC system using a storage battery as a voltage source.

In order to achieve the above object, a power supply system according to the present invention includes a power generation unit that generates power when a power failure occurs in a system power source, a power storage unit that supplies power to the power generation unit, and a power generation unit configured to generate power when the system power source fails. The power storage means is charged by an output, the amount of charge to be supplied to the power storage means is determined based on the determination conditions of the power generation output of the power generation means and the power storage output of the power storage means, and an operation mode is selected. And charging means to be controlled.

  In the above power feeding system, preferably, the charging unit intermittently determines the power generation output of the power generation unit, and if the power generation unit generates power, continues to charge the power storage unit, and the power generation unit generates power. If stopped, charging to the power storage means may be stopped.

In order to achieve the above object, a power supply program according to the present invention is a power supply program to be executed by a computer installed in a power supply system including a power generation unit, a power storage unit, and a charging unit. And when the system power supply fails, the charging means charges the power storage means with the power generation output of the power generation means, and the charging means generates the power generation output of the power generation means and the power storage output of the power storage means. Is determined according to the determination condition, the operation mode is selected, and the computer is caused to execute a process of controlling the amount of charge supplied to the power storage unit according to the operation mode .

  In the above power supply program, preferably, the power generation output of the power generation means is determined intermittently, and if the power generation means is generating power, the charging of the power storage means is continued, and if the power generation means is stopping power generation, You may make the said computer perform the process which stops charge with respect to an electrical storage means.

In order to achieve the above object, a power feeding method of the present invention is a power feeding method used in a power feeding system including a power generation means, a power storage means, and a charging means, and causing the power generation means to generate power when a power failure occurs in a system power supply. , power failure of the system power supply, said charging means includes a step of causing the charging to the power storage unit by the power generation output of the generator means, said charging means, an energy storage output of the generator output and the storage means of the generator means as judged by the judgment condition by selecting an operation mode, and a step of controlling the charging amount you supplied to the storage means by the operation mode.

In the above power feeding method, the step of intermittently determining the power generation output of the power generation means, the charging of the power storage means is continued if the power generation means is generating power, and the power generation means is stopped if the power generation means is stopped. And stopping the charging of the power storage means.

  According to the present invention, the following effects can be obtained.

  (1) Power can be supplied from the power storage means to the power generation means at the time of a power failure, and the power generation by the power generation means can be controlled to the rated output of the power generation means or in the vicinity thereof, so that efficient power supply can be obtained along with the continuity of power generation.

  (2) The FC system described above can be used as the power generation means, and the storage battery system can be used as the power storage means. Even if such a system is used, power generation is maintained during a power failure without changing the configuration of the FC system. The amount of electricity necessary for storage can be maintained in the electricity storage means.

  (3) The amount of electricity necessary for maintaining the power generation in the electricity storage means can be supplemented, and the power supply to the load can be continuously performed for a long time.

Other objects, features, and advantages of the present invention will become clearer with reference to the accompanying drawings and each embodiment.

It is a figure which shows the electric power feeding system which concerns on 1st Embodiment, and the operation | movement at the time of the power failure. It is a flowchart which shows the process sequence at the time of a power failure. It is a flowchart which shows the process sequence at the time of a power failure. It is a figure which shows the determination information table of an electric power generation output. It is a flowchart which shows the process sequence of the electric power generation output switching at the time of a power failure. It is a figure which shows an example of charge control. It is a figure which shows other charge control. It is a figure which shows the electric power feeding system which concerns on 2nd Embodiment. It is a figure which shows the structural example of a control part. It is a figure which shows a part of electric power feeding system which concerns on other embodiment.

[First Embodiment]

<System configuration>

  FIG. 1A shows a power supply system according to the first embodiment. The configuration shown in FIG. 1A is an example, and the present invention is not limited to such a configuration.

  The power supply system 2 includes an FC system (fuel cell cogeneration system) 4, a power storage system 6, and an interconnection charging circuit 8.

  The FC system 4 is a stationary power generation device and is an example of a power generation means. The FC system 4 may be a solar power generation system or the like. In the FC system 4, when a power failure occurs in the system power supply 10, the power generation output is supplied to the power load 14 by the distribution system 12 and is also supplied to the power storage system 6 by the interconnection charging circuit 8. The power storage system 6 is an example of power storage means. The connected charging circuit 8 is an example of a charging unit.

  A system power supply 10 is connected to the power distribution system 12. When power is supplied to the system power supply 10, system power is supplied from the system power supply 10 to the power load 14. At this time, the power storage system 6 is charged with the received power from the system power supply 10. This power storage system 6 includes a voltage sensor 15. This voltage sensor 15 is a means for monitoring the state of the system power supply 10 and is an example of a power failure detection means for detecting a power failure of the system power supply 10. The voltage sensor 15 is connected to the input end of the power distribution system 12 and detects an input voltage from the power system 10 from the power distribution system 12. By detecting the voltage of the voltage sensor 15, it is possible to know whether or not the system power supply 10 has a power failure.

  A current sensor 16-1 is connected to the power distribution system 12. The current sensor 16-1 is, for example, a current transformer. The current sensor 16-1 is an example of a detection unit for obtaining control information necessary for power generation control of the FC system 4. The current output that is the sensor output of the current sensor 16-1 is used for power generation control of the FC system 4.

  A current sensor 16-2 is installed in the interconnection circuit 18 that connects the FC system 4 to the power distribution system 12. The current sensor 16-2 is an example of a power generation output measuring unit of the FC system 4. The presence or absence of power generation in the FC system 4 can also be known from the sensor output of the current sensor 16-2. This current sensor 16-2 is, for example, a current transformer. That is, the current sensor 16-2 measures the output current of the FC system 4 at the time of a power failure of the system power supply 10. That is, if the output voltage is constant, the transmitted power can be easily obtained from this measured current. The transmitted power measured by the current sensor 16-2 is applied to the power storage system 6 and used for operation control of the power storage system 6.

  The power storage system 6 includes a current sensor 16-3, a storage battery 20, and an inverter (hereinafter referred to as “INV”) 22. The current sensor 16-3 measures the current output from the power storage system 6 to the power distribution system 12 when the system power supply 10 is interrupted. As described above, when the output voltage is constant, the transmission power PA is obtained from this measured current value. This output power PA is converted from the direct current output of the storage battery 20 which is an example of the electrical storage output of the electrical storage system 6 to the alternating current output by the INV 22. The transmitted power PA of the power storage system 6 is output to the power distribution system 12 and added to the power load 14 and the FC system 4.

  At the time of a power failure of the system power supply 10, power is supplied from the power storage system 6 and the FC system 4 generates power. The transmission power PB of the FC system 4 is applied to the power load 14 and the connection charging circuit 8 via the connection circuit 18. In this FC system 4, DC power is generated by a fuel cell, and this DC output is converted into an AC output. This transmission power PB is applied to the interconnection charging circuit 8, and the interconnection charging circuit 8 guides the transmission power to the storage battery 20 as a charge amount PC.

  This interconnection charging circuit 8 includes a current sensor 16-4 and an AC-DC converter (hereinafter referred to as “A / D”) 24. The current sensor 16-4 measures the current in the transmitted power that is led from the grid charging circuit 8 to the storage battery 20. As described above, when the voltage is constant, the transmission power can be easily obtained from the measured current value. The A / D 24 converts the alternating current output of the FC system 4 into direct current. Thereby, the power generation output of the FC system 4 is supplied to the storage battery 20 at the time of a power failure of the system power supply 10. Thereby, the connection charging circuit 8 controls the charge amount PC so that the generated power supplied from the FC system 4 to the power storage system 6 falls within a predetermined output range.

<Operation at power failure>

  FIG. 1B shows the operation of the power feeding system 2 when the system power supply 10 is out of power.

  The power storage system 6 shifts from a series operation to a self-sustained operation when the voltage sensor 15 detects a power failure during a power failure of the system power supply 10. This independent operation is an operation state in which the FC system 4 and the power storage system 6 are made independent from the system power supply 10 when the system power supply 10 is disconnected. When the system power supply 10 is shifted to a self-sustained operation during a power failure, the output of the storage battery 20 is converted into an alternating current by the INV 22. This AC output is output to the power distribution system 12, and the FC system 4 generates power with the electric power. The power generation output of the FC system 4 is supplied to the power load 14 and is also supplied to the interconnection charging circuit 8. The power generation output of the FC system 4 is detected by the current sensor 16-2, and the charging operation of the storage battery 20 is started with this detection.

  At the time of a power failure of the system power supply 10, the power generation output of the FC system 4 is supplied to the interconnection charging circuit 8, and the DC output obtained by AC / DC conversion of the A / D 24 is supplied to the storage battery 20 of the power storage system 6. Thereby, the storage battery 20 of the electrical storage system 6 is continuously charged by the power generation output of the FC system 4. That is, at the time of a power failure of the system power supply 10, the power storage amount of the power storage system 6 used for the FC system 4 is compensated by the power generation output of the FC system 4. As a result, the FC system 4 can continuously generate power.

<Processing procedure of power supply system 2>

  FIG. 2 shows a processing procedure of time series operation at the time of power failure. This processing procedure is an example of the power supply program or power supply method of the present invention.

  In this processing procedure, the state of the system power supply 10 is monitored. A power failure occurs in the system power supply 10 (S11), and this power failure is detected by the voltage sensor 15 (S12). In response to this power failure detection, the power of the storage battery 20 is supplied from the power storage system 6 to the power load 14 and the FC system 4 (S13).

  The FC system 4 generates power using the power of the storage battery 20 (S14). In this case, if the power storage system 6 is stopped, power generation is started after the power storage system 6 is activated.

  The electric power generated by the FC system 4 charges the storage battery 20 of the power storage system 6 through the interconnection charging circuit 8 (S15).

  FIG. 3 shows a processing procedure (main routine) at the time of a power failure. This processing procedure is an example of the power supply method or power supply program of the present invention. This power supply program is a program for causing the computer of the power supply system 2 to execute.

  In this processing procedure, a power failure is detected by starting the processing (S21). This power failure detection is performed by the detection output of the voltage sensor 15 in the distribution system 12 as described above. During this power failure, the FC system 4 generates power.

  Therefore, it is determined whether the FC system 4 is generating power (S22). The presence or absence of this power generation is determined by the detection output of the current sensor 16-2.

  When the FC system 4 is not generating power (NO in S22), the charging of the storage battery 20 of the power storage system 6 is stopped (S23). Thereby, a decrease in the amount of electricity stored in the storage battery 20 is prevented.

  If the FC system 4 is generating power (YES in S22), the storage battery 20 of the power storage system 6 is charged (S24). As described above, in this charging, the power generation output of the FC system 4 is converted into a DC output by the A / D 24 of the interconnection charging circuit 8, and the storage battery 20 is charged by this DC output. This charging is continuously performed as long as the FC system 4 continues to generate power.

  Then, power recovery is detected (S25). When power is restored (YES in S26), charging of the storage battery 20 of the power storage system 6 is stopped (S23). If the power failure continues (NO in S26), the process returns to step (S22) and the processes in steps 22 to 25 are continued.

  FIG. 4 shows the determination information table 25. This determination information table 25 shows the determination conditions (that is, mode selection conditions) for the operation modes I, II, and III based on the combination of the transmission powers PA and PB described above. The storage amount PC of the storage battery 20 is given by the transmission power of the grid charging circuit 8 as described above.

  In this determination information table 25, 100 [W] is used as an example of the output determination threshold Pn for the transmission power PA, and 700 [W] is used as an example of the output determination threshold Pm for the transmission power PB. For the transmission power PA, PA <Pn (= 100 [W]) and PA ≧ Pn are set as determination conditions. For the transmission power PB, PB <Pm (= 700 [W]) and PB ≧ Pm are set as determination conditions.

  Therefore, using this determination information table 25, mode selection is performed as follows.

  (1) If PA <Pn and PB <Pm, the operation mode I is selected. In order to increase the power generation output of the FC system 4, in this operation mode I, the charge amount PC of the storage battery 20 by the interconnection charging circuit 8 is increased.

  (2) If PA ≧ Pn and PB ≧ Pm, the operation mode II is selected. Since the power generation output of the FC system 4 is sufficient and the output of the INV 22 of the power storage system 6 is excessive, in this operation mode II, the charge amount PC of the storage battery 20 by the grid charging circuit 8 is decreased.

  (3) If PA ≧ Pn and PB <Pm, the operation mode IIIb is selected. In order to wait for an increase in the power generation output of the FC system 4, in this operation mode IIIb, the charging amount PC of the storage battery 20 by the interconnection charging circuit 8 is maintained and waits.

  (4) If PA <Pn and PB ≧ Pm, the operation mode IIIa is selected. Since the power generation output of the FC system 4 is sufficient and the output of the INV 22 is appropriate, in this operation mode IIIa, the charging amount PC of the storage battery 20 is maintained and waited by the output power of the interconnection charging circuit 8. That is, it is substantially the same as the operation mode IIIb of (3).

  FIG. 5 shows an operation mode switching process procedure using the transmission powers PA and PB.

  This processing procedure is an example of the power supply method or power supply program of the present invention. This processing procedure is a program for causing a computer installed in the power supply system 2 to execute.

  In this processing procedure, at the time of a power failure of the system power supply 10, the power storage system 6 shifts to charging (S31). In response to the transition of the charging, the operation mode I, II, III (IIIa or IIIb) is selected (S32). In this mode selection, the transmission powers PA and PB are determined (S33). For this determination, the above-described determination information table 25 (FIG. 4) is used.

  For this determination, reference is made to the transmission power PA measured by the current sensor 16-3 and the transmission power PB measured by the current sensor 16-2. As described above, if PA <Pn and PB <Pm, the operation mode I is selected. If PA ≧ Pn and PB <Pm, the operation mode IIIb is selected, and PA <Pn and PB ≧ Pm. If there is, the operation mode IIIa is selected, and if PA ≧ Pn and PB ≧ Pm, the operation mode II is selected.

  When the operation mode I is selected (S34), the charge amount PC of the storage battery 20 by the interconnection charging circuit 8 is increased to the charge amount PC obtained by adding a constant power ΔP. In this case, the power ΔP may be set to ΔP = 50 [W], for example. This value is a slight increase from the rated output of the FC system 4.

  When the operation mode III is selected (S35), the charge amount PC of the storage battery 20 by the interconnection charging circuit 8 is maintained at the same value.

  When the operation mode II is selected (S36), the charge amount PC of the storage battery 20 by the interconnection charge circuit 8 is reduced to the charge amount PC obtained by subtracting a constant power ΔP.

  After setting to one of these operation modes, the system waits for a certain waiting time (S37). This waiting time is, for example, 10 [seconds].

  After this waiting time, the transmission powers PA and PB are determined (S38). This transmission power is determined by determining whether PA> Pn and PB <Ps. In this case, as described above, Pn is, for example, 100 [W], and Ps is Ps = 50 [W].

  If PA> Pn and PB <Ps are satisfied (YES in S39), charging is stopped (S40). In this case, the FC system 4 determines that the operation is stopped, and stops the charging operation by the interconnection charging circuit 8.

  On the other hand, if PA> Pn and PB <Ps are not satisfied (NO in S39), the process returns to S32, and the processes of S32 to S39 are continuously performed. That is, it is possible to intermittently determine the power generation of the FC system 4 and continue charging if it is generating power, and stop charging if it is not generating power.

  FIG. 6 shows the charging control of the storage battery 20 of the power storage system 6. In this charge control, the amount of charge of the storage battery 20 is adjusted using the operation mode described above. This charging control employs interval determination based on intermittent power determination. That is, the power transition according to the processing procedure described above is obtained.

  In FIG. 6, the horizontal axis represents time t, the vertical axis represents power (current), the transmission output PA, PB, the amount of charge PC, the output power PB output determination threshold Pm, the transmission power PA determination threshold Pn, and the power. The power PL of the load 14 and the rated output Po of the FC system 4 are shown.

  A power failure has occurred in the system power supply 10 at time t1. This time t1 is the start of charging with the transmission power PB of the FC system 4 for the storage battery 20. And time t2 is a power recovery time, and charging stops at this time. In the time from the time point t1 to the time point t2, the operation modes I, II, and III are intermittently selected by the output determination (determination performed at a constant time interval) according to the above-described processing procedure.

  In this case, as a basic operation, it is determined that there is the transmission power PB at the time t1 when the power failure occurs. If the transmission power PB exists, charging of the storage battery 20 by the grid charging circuit 8 is started.

  The values (power or current) of the transmitted power PA and PB are determined at regular time intervals (intervals), and increase / decrease control of the charged power transmitted from the grid charging circuit 8 to the storage battery 20 is performed. In FIG. 6, PA1, PA2,... PA16 indicate power at the time of output determination of the transmission power PA. PB1, PB2,... PB15 indicate power at the time of output determination of the transmission power PB. The CP area indicates an increase in the amount of power stored in the storage battery 20.

In this case, the relational expression of the charging power for the storage battery 20 is
PA + PB = PL + PC (1)
It is. In Expression (1), PA is the transmission power of the power storage system 6, and PB is the transmission power of the FC system 4. PC is a charge amount given by the transmission power of the interconnection charging circuit 8. In addition, PL is power transmitted to the power load 14 and is power consumption.

  As apparent from the equation (1), the sum of the transmission power PA of the power storage system 6 and the transmission power PB of the FC system 4 is the charge amount PC of the transmission power PL to the power load 14 and the transmission power of the interconnection charging circuit 8. Equal to the sum.

  Therefore, when the power load 14 increases rapidly, the increase is supplemented with the transmitted power PA from the power storage system 6 with high followability. And with respect to the electrical storage system 6, the transmission electric power PB from the FC system 4 inferior in followability is gradually increased. As a result, the increase in the power load 14 is complemented by the output of the power storage system 6 and the output of the FC system 4.

  Further, when the power load 14 is suddenly reduced, the sudden reduction is dealt with by the power reduction of the power storage system 6 with quick followability. In this case, when the followability of the FC system 4 is as high as that of the power storage system 6, the power reduction of the power storage system 6 is preceded, and the power that cannot be handled by the power storage system 6 is handled by the power reduction of the FC system 4. do it. Thereby, the speed of power tracking and the quick response of weight reduction can be improved.

  In this embodiment, FIG. 7 shows another charge control. In FIG. 6, as described above, the charge amount adjustment is performed at predetermined time intervals, whereas in FIG. 7, the power transition by the constant tracking method is shown.

  Even in this follow-up method, the principle operation is the same as that of the interval determination method, but it shows a continuous power transition and the determination threshold value is different. Specifically, the interval time is extremely short, the amount of increase / decrease in the charge amount PC is small, the output determination value Pn of the transmission power PA approaches the minimum power Ps of the system power supply 10 required by the FC system 4, and the transmission power The output judgment value Pm of PB tends to approach the rated output Po of the FC system 4.

<Features and effects of the first embodiment>

  (1) A current sensor 16-3 that measures the transmission power PA (current) of the power storage system 6, a current sensor 16-2 that can measure the transmission power PB of the FC system 4, and the transmission power (that is, charging) of the interconnection charging circuit 8 A current sensor 16-4 capable of measuring (power: current) is provided, and an operation mode can be determined by a combination of the transmission powers PA and PB. The charge amount PC of the storage battery 20 can be monitored by the transmitted power.

  (2) The charge amount PC of the storage battery 20 can be adjusted under the operation mode conditions based on the transmission powers PA and PB.

  (3) Thereby, the FC system 4 can be generated with the rated power or a value close to it, and the power supply time during a power failure can be extended more efficiently.

  (4) By intermittently determining whether or not the FC system 4 generates power, if the FC system 4 is stopped, the charging of the storage battery 20 from the interconnection charging circuit 8 is stopped, and the FC system 4 generates power. If so, the charging from the grid charging circuit 8 to the storage battery 20 is continued. Thereby, efficient charging becomes possible. As a result, when the FC system 4 is stopped, the power supply time during a power failure can be maintained longer by stopping the charging.

  (5) By the above, the storage battery 20 can be efficiently charged by the FC system 4 and the charge amount PC can be maximized. As a result, the storage battery 20 maintains the storage amount PC during a power failure. it can. Thereby, the power supply to the power load 14 can be prolonged.

  (6) According to such a configuration, it is possible to realize a high-performance operation by using an existing system without changing the FC system 4.

[Second Embodiment]

<System configuration>

  FIG. 8 shows a power feeding system according to the second embodiment. In FIG. 8, the same parts as those in FIG.

  The FC system 4 of this embodiment includes a power generation unit 26 and a control unit 28. The power generation unit 26 may be any power generation means such as a fuel cell or a solar panel. The power generation output of the FC system 4 is fed from the distribution system 12 to the power load 14. The control unit 28 is configured by a computer and controls a power generation operation such as when the power generation unit 26 generates power.

  A detection output of the current sensor 16-1 in the power distribution system 12 is added to the control unit 28 as a control input. Therefore, the control unit 28 receives the output of the current sensor 16-1 and controls the power generation amount of the power generation unit 26.

  The power storage system 6 includes a current sensor 16-3, a storage battery 20, an INV 22, and a control unit 30. The storage battery 20 is an example of a secondary battery that can be charged and discharged. The INV 22 converts the output of the storage battery 20 into an AC output and outputs it to the power distribution system 12. The control unit 30 is configured by a computer, and the output of the current sensor 16-2 in the interconnection circuit 18 is applied as a control input. At the time of a power failure of the system power supply 10, it is detected from the current value of the current sensor 16-2 whether or not the FC system 4 is in a power generation state. During power generation by the FC system 4, the power storage system 6 starts charging the storage battery 20.

  The charging battery 8 is used for charging the storage battery 20. The interconnection charging circuit 8 includes a current sensor 16-2, an A / D 24, a charging path 32, a charging switching unit 34, and a control unit 36. The charging path 32 supplies the power generation output of the FC system 4 to the A / D 24 and supplies the conversion output of the A / D 24 to the storage battery 20 of the power storage system 6.

  The charge switching unit 34 is controlled to the above-described operation mode I, II, or III by the output of the control unit 36.

  The control unit 36 receives the measurement outputs of the current sensors 16-2, 16-3, and 16-4, and generates the operation mode selection output shown in the first embodiment. Thereby, the charge switching unit 34 is controlled. With this control, the charge amount PC is adjusted by the charge control of the storage battery 20.

  According to such a configuration, the charging control of the storage battery 20 described in the first embodiment can be realized.

  FIG. 9 shows an example of hardware of the control unit 36. As described above, the control unit 36 is constituted by a microcomputer. The control unit 36 includes a processor 38, a memory 40, a RAM (Random-Access Memory) 42, and an input / output unit 44, which are interconnected by a bus 46.

  The processor 38 executes various programs such as an OS (Operating System) stored in the memory 40. In this processor 38, the operation mode I, II or III (IIIa or IIIb) is set when the FC switching system 34 generates power by the detection output of the current sensors 16-2, 16-3 and 16-4 to the input / output unit 44. Control output to stop charging when the operation of the FC system 4 is stopped.

  The memory 40 stores a program such as the OS described above. The RAM 42 constitutes a work area for information processing. The input / output unit 44 is used to input detection outputs of the current sensors 16-2, 16-3, and 16-4 and to take out control outputs. This memory 40 stores the above-described determination information table 25 (FIG. 4).

<Effects of Second Embodiment>

  (1) According to this embodiment, the charge amount of the storage battery 20 can be adjusted according to the above-described conditions using the transmission powers PA and PB. Moreover, the presence or absence of the power generation of the FC system 4 or the transmission power PB is intermittently determined. Based on this determination, if the FC system 4 is generating power, the storage battery 20 is continuously charged, and the FC system 4 generates power. Since the charging of the storage battery 20 is stopped if it is stopped, the same effects as those of the first embodiment can be obtained, for example, the storage battery 20 can be charged efficiently. That is, inconveniences such as an increase in power loss of the storage battery 20 and a decrease in the amount of power stored in the storage battery 20 can be avoided, and continuity of power supply and longer time can be achieved during a power failure.

  (2) When the amount of charge is larger than the generated power of the FC system 4, there is an increase in the amount of discharge of the storage battery 20 of the power storage system 6 and the power loss in the charging process accompanying the increase of the amount of charge with respect to the discharged power of the power storage system 6. Inconveniences such as increase can be avoided. Efficient charging control for the storage battery 20 is obtained.

  (3) When the amount of charge of the storage battery 20 is small and the amount of charge is less than the rated power of the FC system 4, more charge is possible, and the amount of charge becomes insufficient to ensure the amount of stored electricity. Inconvenience can be avoided. That is, the storage battery 20 can be appropriately charged.

  (4) When the FC system 4 is stopped after the charging of the storage battery 20 by the output power of the connection charging circuit 8 is started, the charging by the connection charging circuit 8 can be stopped immediately. As a result, an increase in power loss can be suppressed, and the inconvenience of reducing the amount of power stored in the storage battery 20 due to continued charging can be avoided. Thereby, the reliability of charge with respect to the storage battery 20 can be improved.

  (5) As described above, while supplying electric power to the electric power load 14, the storage battery 20 can be appropriately charged, the power generation of the FC system 4 can be continued, and the power supply time can be extended.

[Other Embodiments]

  As shown in FIG. 10, a display unit 48 may be provided. By giving a display output from the control unit 36 to the display unit 48, the power outage state or the power supply state, the operation status of the FC system 4, the switching of the operation mode and the transition thereof, the storage amount of the storage battery 20 and the transition thereof are displayed. May be.

As described above, the most preferable embodiment of the present invention has been described. The present invention is not limited to the above description. Various modifications and changes can be made by those skilled in the art based on the gist of the invention described in the claims or disclosed in the embodiments for carrying out the invention. It goes without saying that such modifications and changes are included in the scope of the present invention.

In the present invention, a power generation unit such as an existing FC system or a power storage unit such as a power storage system is used to charge a storage battery in the power storage unit with a power generation output of the power generation unit. For this charging, efficient charging is realized by referring to the transmission power of the power storage unit and the transmission power of the power generation unit, and power can be supplied for a long time during a power failure.

2 Power Supply System 4 FC System 6 Power Storage System 8 Interconnection Charging Circuit 10 System Power Supply 12 Distribution System 14 Power Load 15 Voltage Sensor 16-1, 16-2, 16-3, 16-4 Current Sensor 18 Interconnection Circuit 20 Storage Battery 22 Inverter 24 AC-DC converter 26 Power generation unit 28 Control unit 30 Control unit 32 Charging path 34 Charge switching unit 36 Control unit 38 Processor 40 Memory 42 RAM
44 I / O 46 Bus

Claims (6)

Power generation means for generating power in the event of a grid power failure,
Power storage means for supplying power to the power generation means;
At the time of a power failure of the system power supply, the power storage means is charged by the power generation output of the power generation means, and the amount of charge supplied to the power storage means is determined according to the determination condition of the power generation output of the power generation means and the power storage output of the power storage means A charging means for determining and selecting an operation mode and controlling the operation mode ;
A power supply system comprising: The charging means intermittently determines the power generation output of the power generation means, and continues to charge the power storage means if the power generation means is generating power, and the power storage means if the power generation means has stopped power generation. The power feeding system according to claim 1, wherein charging to the battery is stopped. A power supply program to be executed by a computer mounted on a power supply system including a power generation means, a power storage means, and a charging means ,
At the time of power failure of the system power supply, the power generation means generates power,
At the time of a power failure of the system power supply, the charging unit causes the power storage unit to charge with the power generation output of the power generation unit
It said charging means, said power storage output of the generator output and the storage means of the power generator is determined by the determination condition and selecting an operation mode, controls the charging amount you supplied to the storage means by the operation mode,
Power supply program for causing computer to execute processing Intermittently determining the power generation output of the power generation means,
If the power generation means is generating electricity, continue charging the power storage means,
The power supply program according to claim 3 , wherein if the power generation means stops power generation, the computer executes a process of stopping charging of the power storage means. A power feeding method used in a power feeding system including a power generation means, a power storage means, and a charging means ,
A step of causing the power generation means to generate power in the event of a power failure of the system power supply;
At the time of a power failure of the system power supply, the charging unit charging the power storage unit with the power generation output of the power generation unit;
A step wherein the charging means, wherein said power storage output of the generator output and the storage means of the power generator is determined by the determination condition and selecting an operation mode, controls the charging amount you supplied to the storage means by the operation mode,
A power supply method comprising: Intermittently determining the power generation output of the power generation means;
If the power generation means is generating power, continuing to charge the power storage means; if the power generation means has stopped generating power, stopping charging the power storage means;
The power feeding method according to claim 5 , comprising:

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