JP2018152948A - Power supply system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power supply system which comprises multiple storage battery systems and is capable of appropriately working the storage battery systems.SOLUTION: A power supply system comprises: multiple branch cable ways L1-Lm which are branched from each other and to which power load G1-Gm (described as G hereafter) are connected, as a part of a cable way connecting a system power source 100 with the power loads G; storage battery systems 1b-Mb (described as B hereafter) for group that are provided correspondingly to the power loads G; fuel cell systems 11f-1nf, ..., M1f-Mnf that are connected between the power loads G and the storage battery systems B; and a control part which controls operations of the storage battery systems B based on detection result of power detection parts 1d-Md and Dd. In a case where an inverse load flow to the system power source 100 is detected, storage battery systems B in discharge states are extracted from among the storage battery systems B that are connected with the power loads G, and the discharge states of the extracted storage battery system B are stopped successively from least residual battery power.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a technology of a power supply system including a storage battery system and a fuel cell system.

  Conventionally, the technology of a power supply system including a storage battery system and a fuel cell system has been publicly known. For example, as described in Patent Document 1.

  Patent Document 1 discloses a fuel cell system (power supply) including a storage battery (storage battery system), a power generation unit (fuel cell system) that generates electric power, and an acquisition unit that acquires battery information indicating a storage state of the storage battery. System) is described. In the fuel cell system, the storage battery and the power generation unit are linked based on the battery information.

  With this configuration, if you do not want to reverse power flow to the grid power supply (for example, if the power flow to the grid power supply does not allow compensation for the reverse power flow from the power company) The power generated by the power generation unit can be charged into the storage battery, and the reverse power flow from the power generation unit to the system power supply can be reduced.

International Publication No. 2013-179661

  However, the power supply system described in Patent Document 1 is provided with only one storage battery. Therefore, when the storage battery cannot be charged, there is a possibility that the generated power of the power generation unit may flow backward to the system power supply even if it is not desired to reverse power flow to the system power supply. Moreover, the power supply system described in Patent Document 1 does not assume that a plurality of storage batteries are provided. For example, when a plurality of storage batteries are provided, the power supply system does not disclose how to operate these storage batteries.

  The present invention has been made in view of the situation as described above, and a problem to be solved is to provide a power supply system that includes a plurality of storage battery systems and can suitably operate these storage battery systems. Is.

  The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described.

  That is, in claim 1, a part of the electric circuit connecting the system power supply and the load, and a plurality of branch electric circuits branched from each other and connected to the load, respectively, are provided corresponding to each load, A first storage battery system connected to each corresponding load via each branch circuit, a fuel cell system connected between each load and each first storage battery system corresponding to each load, and a system power supply And a control unit that controls the operation of the first storage battery system based on the detection result of the detection unit, and the control unit detects the power flowing to the system power supply. If the first storage battery system connected to each load is extracted, the first storage battery system in a discharged state is extracted, and the remaining battery power is extracted from the extracted first storage battery system in the discharged state. Discharge from lowest to highest It is intended to stop the state.

  The second storage battery system according to claim 2, further comprising a second storage battery system connected to an electrical path connecting the plurality of branch electrical paths and a system power supply, wherein the control unit is configured to perform the second storage battery system based on a detection result of the detection unit. When the first storage battery system connected to each load is in a charged state, the second storage battery system is set in a charged state.

  In claim 3, the first storage battery system connected to each of the loads is in a charge / discharge stopped state, and power is flowing to a system power supply side through a connection portion with the branch electric circuit. When there is a storage battery system, the first storage battery system in which power is flowing to the system power supply side through the connection with the branch electric circuit is set in a charged state in ascending order of remaining battery power.

  In claim 4, further comprising a second storage battery system connected to a circuit connecting the plurality of branch circuits and the system power supply, the detection unit is capable of detecting the power flowing from the system power supply, A control part makes said 2nd storage battery system into a discharge state, when the electric power which flows from a system power supply is detected.

  In claim 5, when the second storage battery system is in a discharged state and there is the first storage battery system in which power flows to the load side through a connection portion with the branch electric circuit, the branch is provided. In the first storage battery system in which power is flowing to the load side through the connection portion with the electric circuit, the discharge state is set in descending order of the remaining battery level.

  In claim 6, when the second storage battery system is in a discharged state and there is no first storage battery system in which power is flowing to the load side through a connection portion with each branch circuit, The first storage battery system in the charged state is extracted from the first storage battery systems connected to each load, and the charged state is stopped in descending order of the remaining battery power in the extracted first storage battery system in the charged state. Is.

  The control unit can acquire information on the power generation state of the fuel cell system, and the control of the control unit is based on information on the power generation state in addition to the detection result of the detection unit. It is done.

  As effects of the present invention, the following effects can be obtained.

  In this invention, a some storage battery system is comprised and these storage battery systems can be moved suitably.

The block diagram which showed the structure of the electric power supply system which concerns on 1st embodiment of this invention. Similarly, the block diagram which showed the structure of the control part. Similarly, the block diagram which showed an example of the supply aspect of electric power. Similarly, the block diagram which showed an example of the supply aspect of electric power. Similarly, the flowchart which showed the process of the reverse power flow suppression control which concerns on 1st embodiment. Similarly, the flowchart which showed the continuation of FIG. Similarly, the flowchart which showed the continuation of FIG. Similarly, the block diagram which showed an example of the supply aspect of electric power. Similarly, the block diagram which showed an example of the supply aspect of electric power. Similarly, the block diagram which showed an example of the supply aspect of the electric power following FIG. Similarly, the block diagram which showed an example of the supply aspect of the electric power following FIG. Similarly, the block diagram which showed an example of the supply mode of the electric power following FIG. The block diagram which showed the structure of the control part of the electric power supply system which concerns on 2nd embodiment of this invention. Similarly, the flowchart which showed the process of the reverse power flow suppression control which concerns on 2nd embodiment. Similarly, the flowchart which showed the continuation of FIG. Similarly, the flowchart which showed the continuation of FIG.

  Below, the electric power supply system 1 which concerns on one Embodiment of this invention is demonstrated using FIG. 1 and 2. FIG.

  The power supply system 1 is introduced into a condominium (collective housing) having a plurality of residences H. The power supply system 1 is a system that appropriately supplies power from the system power supply 100, a fuel cell system F, which will be described later, and a storage battery system B to each residence H.

  First, an outline of an apartment where the power supply system 1 is introduced will be described.

  The plurality of residences H of the apartment are divided into a plurality of groups depending on the connection mode with the system power supply 100. Each residence H is provided with an appropriate electrical product (electric power load) that consumes the supplied power. Thus, in this embodiment, the connection between each residence H and the system power supply 100 indicates the connection between the power load of each residence H and the system power supply 100 in more detail.

  The plurality of residences H are divided into the first group G1, the second group G2, and the Mth group Gm as the plurality of groups. Note that “M” and “m” are assigned the numbers grouped according to the structure of the apartment where the power supply system 1 is introduced. The first group G1 is connected to the system power supply 100 via the electric circuit L1. The second group G2 to the Mth group Gm are connected to the system power supply 100 via an electric circuit branched from the electric circuit L1. For example, the second group G2 is connected to the system power supply 100 via the electric circuit L1a and the electric circuit L2 branched from the electric circuit L1. In addition, the Mth group Gm is connected to the system power supply 100 via an electric circuit L1a and an electric circuit Lm branched from the electric circuit L1. In the following, the system power supply 100 side in each electric circuit is referred to as an upstream side, and each residence H side is referred to as a downstream side.

  The first group G1 includes a residence 11, a residence 12,..., A residence 1n among the plurality of residences H. Note that the downstream end of the electric circuit L1 connected to the first group G1 is branched into a plurality. Thus, the residence 11, the residence 12,..., The residence 1n are respectively connected to the branched downstream end of the electric circuit L1.

  Among the plurality of residences H, the second group G2 includes a residence 21, a residence 22,..., A residence 2n. The downstream end of the electric circuit L2 connected to the second group G2 is branched into a plurality. Thus, the residence 21, the residence 22,..., The residence 2n are respectively connected to the branched downstream end of the electric circuit L2.

  The Mth group Gm includes a residence M1, a residence M2,..., A residence Mn among the plurality of residences H. The downstream end of the electric circuit Lm connected to the Mth group Gm is branched into a plurality. Thus, the residence M1, the residence M2,..., The residence Mn are respectively connected to the branched downstream end of the electric circuit Lm.

  Note that the number of residences per group is substituted for “n” according to the structure of the apartment where the power supply system 1 is introduced.

  Below, the structure of the electric power supply system 1 is demonstrated in detail.

  1 and 2 mainly includes a fuel cell system F, a storage battery system B, a power detection unit D, and an EMS 20.

  The fuel cell system F generates power using fuel (in this embodiment, city gas). The fuel cell system F includes a solid oxide fuel cell (SOFC: Solid Oxide Fuel Cell), a control unit (not shown), and the like. The fuel cell system F is set to always generate power at the maximum output. In the present embodiment, the maximum output (maximum generated power) of the fuel cell system F is set to 700W.

  In addition, the fuel cell system F is connected to the system power source 100 (in connection with the system power source 100) and connected to the system power source 100 and connected to the system power source 100. It is possible to perform switching operation that is canceled (disconnected from the system power supply 100) and supplies power to the residence H (electric power load). When the fuel cell system F performs a self-sustained operation, the fuel cell system F enters a standby state by consuming the generated power itself. Note that, in the fuel cell system F, in the standby state, the generated power is substantially 0 (hereinafter referred to as 0).

  Thus, the fuel cell system F is set so that the generated power is 700 W during the interconnected operation and the generated power is 0 W during the independent operation.

  Further, in the fuel cell system F, the amount of city gas (fuel) used is different when compared with the case of performing the interconnected operation and the case of performing the independent operation. In the present embodiment, the fuel cell system F is more independent when performing autonomous operation (more specifically, when generating power is not extracted from the fuel cell system F during autonomous operation) than when performing interconnected operation. Thus, the amount of city gas used will be about 1/3.

  In addition, the fuel cell system F may stop its power generation operation every predetermined period (for example, every month) for maintenance or the like.

  The fuel cell system F is provided (owned) in each residence H. Specifically, the fuel cell system 11f, the fuel cell system 12f,..., And the fuel cell system 1nf are provided in the residence 11, the residence 12,. The fuel cell system 11f, the fuel cell system 12f,..., And the fuel cell system 1nf are connected in order from the upstream side to the downstream side in the middle of the electric circuit L1.

  Moreover, the fuel cell system 21f, the fuel cell system 22f,..., And the fuel cell system 2nf are provided in the residence 21, the residence 22,. The fuel cell system 21f, the fuel cell system 22f,..., The fuel cell system 2nf are connected in order from the upstream side to the downstream side in the middle portion of the electric circuit L2.

  In addition, a fuel cell system M1f, a fuel cell system M2f,..., And a fuel cell system Mnf are provided in each of the houses M1, M2,. The fuel cell system M1f, the fuel cell system M2f,..., The fuel cell system Mnf are connected in order from the upstream side to the downstream side in the middle portion of the electric circuit Lm.

  The storage battery system B charges and discharges electric power from the system power supply 100 and the fuel cell system F as appropriate. The storage battery system B includes a chargeable / dischargeable storage battery, a power conditioner for controlling charge / discharge of the storage battery, and the like. The storage battery system B has a load following function that discharges electric power based on the magnitude of electric power flowing to the electric load side through a connection portion with the electric circuit. The storage battery system B can execute a plurality of modes related to operations such as charging and discharging. The plurality of modes include an eco mode and a stop mode.

  The eco mode is a mode for using the generated power of the fuel cell system F in the apartment as much as possible. When the eco mode is executed, surplus power surplus with respect to the power load of the residence H out of the generated power of the fuel cell system F is charged to the storage battery system B instead of being reversely flowed to the system power supply 100. The When the power generated by the fuel cell system F is insufficient with respect to the power load of the residence H, the power discharged from the storage battery system B is supplied to the power load of the residence H in order to cover the shortage. The

  The stop mode is a mode for stopping the operation of the storage battery system B. When the stop mode is executed, the storage battery system B stops operating, and charging / discharging becomes impossible.

  The storage battery system B includes a storage battery system B provided for each of a plurality of groups, and a storage battery system B provided for only one group as a whole. Specifically, the storage battery systems B provided one by one in the plurality of groups are a storage battery system 1b, a storage battery system 2b,..., A storage battery system Mb. Moreover, the storage battery system B provided only one as said whole several group is storage battery system Bb. Hereinafter, the storage battery systems B provided one by one in each of the plurality of groups are collectively referred to as a group storage battery system B.

  The storage battery system 1b is connected downstream of the connecting portion with the electric circuit L1a in the electric circuit L1 and upstream of the fuel cell system 11f, the fuel cell system 12f, ..., the fuel cell system 1nf. The Further, the storage battery system 2b is connected upstream of the fuel cell system 21f, the fuel cell system 22f,..., The fuel cell system 2nf in the electric circuit L2. Further, the storage battery system Mb is connected to the upstream side of the fuel cell system M1f, the fuel cell system M2f,.

  In addition, the storage battery system Bb is connected to the upstream side of the connection portion with the electric circuit L1a in the electric circuit L1.

  Thus, the storage battery system B for each group is connected to the most upstream side in each group (more specifically, in the electric circuit to which each group is connected). The storage battery system Bb is connected to the upstream side of the storage battery systems B for all groups.

  In this way, the storage battery system Bb is surplus power with respect to the power load among the generated power of the fuel cell system F of each group, and the power that the storage battery system B for each group could not fully charge flows upstream. In this case, it is possible to prevent the electric power flowing to the upstream side from being charged and flowing to the system power source 100. As described above, the storage battery system Bb has a function as a final protection means in order to prevent the generated power of the fuel cell system F of each group from flowing to the system power supply 100. For this reason, the storage battery system Bb is preferentially discharged compared to the storage battery systems B for other groups so as to maintain a state where the remaining battery capacity is low in reverse power flow suppression control to be described later (in order to keep the charge capacity open). Is done.

  The power detection unit D detects power. The power detection unit D includes a plurality of sensors.

  Specifically, the power detection unit D includes a fuel cell system 11f, a fuel cell system 12f,..., A sensor 11d that detects power from the fuel cell system 1nf, a sensor 12d,. It is. The sensor 11d, the sensor 12d, ..., the sensor 1nd are provided between the fuel cell system 11f, the fuel cell system 12f, ..., the fuel cell system 1nf and the electric circuit L1, respectively.

  The power detection unit D includes a fuel cell system 21f, a fuel cell system 22f,..., A sensor 21d that detects power from the fuel cell system 2nf, a sensor 22d,. The sensor 21d, the sensor 22d, ..., the sensor 2nd are provided between the fuel cell system 21f, the fuel cell system 22f, ..., the fuel cell system 2nf and the electric circuit L2, respectively.

  The power detection unit D includes a fuel cell system M1f, a fuel cell system M2f,..., A sensor M1d that detects power from the fuel cell system Mnf, a sensor M2d,. The sensor M1d, the sensor M2d,..., The sensor Mnd are provided between the fuel cell system M1f, the fuel cell system M2f,.

  Thus, among the power detection units D, the sensor 11d, the sensor 12d, ..., the sensor 1nd, the sensor 21d, the sensor 22d, ..., the sensor 2nd, the sensor M1d, the sensor M2d, ..., the sensor Mnd. Can detect the generated power of the corresponding fuel cell system F.

  Further, the power detection unit D includes a sensor 1d, a sensor 2d,..., A sensor Md, and a sensor Dd as sensors for detecting the power flowing through the connection part between the storage battery system B and the electric circuit.

  The sensor 1d is provided in the electric circuit L1 immediately upstream of the connection part of the electric circuit L1 and the storage battery system 1b. Moreover, the sensor 2d is provided in the electric circuit L2 in the immediately upstream of the connection part of the said electric circuit L2 and the storage battery system 2b. Moreover, the sensor Md is provided in the electric circuit Lm immediately upstream of the connection part of the said electric circuit Lm and the storage battery system Mb.

  Moreover, the sensor Dd is provided in the electric circuit L1 in the immediately upstream of the connection part of the said electric circuit L1 and storage battery system Bb. The sensor Dd includes power supplied from the system power supply 100 (power purchase) and power supplied to the system power supply 100 (reverse power flow) (power sales) as power flowing through the connection between the electric circuit L1 and the storage battery system Bb. ) Can be detected.

  In the present specification, the power supplied from the system power supply 100 is referred to as “power purchase” as appropriate. However, the consideration for the power supplied from the system power supply 100 is not necessarily limited to the power paid to the power company. Similarly, the power supplied (reverse power flow) to the system power supply 100 is appropriately referred to as “power sale”, but the consideration for the power backflowed to the system power supply 100 is not necessarily limited to the power paid by the power company. Not intended. As described above, in this specification, “power purchase” and “power sale” do not matter whether or not the consideration is paid.

  In addition, the sensor 1d, the sensor 2d,..., The sensor Md, and the sensor Dd are electrically connected to the corresponding storage battery system B, respectively. The sensor 1d, the sensor 2d,..., The sensor Md, and the sensor Dd are configured to be able to output predetermined signals to the corresponding storage battery systems B, respectively.

  Specifically, the sensor 1d is connected to the storage battery system 1b as the corresponding storage battery system B. Thus, the storage battery system 1b can acquire the detection result of the sensor 1d. The sensor 2d is connected to the storage battery system 2b as the corresponding storage battery system B. Thus, the storage battery system 2b can acquire the detection result of the sensor 2d. The sensor Md is connected to the storage battery system Mb as the corresponding storage battery system B. Thus, the storage battery system Mb can acquire the detection result of the sensor Md. The sensor Bd is connected to the storage battery system Bb as the corresponding storage battery system B. Thus, the storage battery system Bb can acquire the detection result of the sensor Bd.

  The EMS 20 is an energy management system that manages the operation of the power supply system 1. The EMS 20 includes a storage unit such as a RAM and a ROM, an arithmetic processing unit such as a CPU, an input / output unit such as an I / O. The EMS 20 can perform predetermined arithmetic processing, storage processing, and the like. The EMS 20 stores in advance various information, programs, and the like for managing the operation of the power supply system 1.

  The EMS 20 is electrically connected to each storage battery system B as shown in FIG. The EMS 20 is configured to be able to output a predetermined signal to each storage battery system B. Thus, the EMS 20 can control the operation of each storage battery system B (for example, switching between the eco mode and the stop mode). The EMS 20 is configured such that a predetermined signal can be input from each storage battery system B. Thus, the EMS 20 can acquire information regarding the operation of each storage battery system B.

  The EMS 20 is electrically connected to the power detection unit D. The EMS 20 is configured such that a predetermined signal can be input from the power detection unit D (more specifically, the sensor 11d and the like). In this way, the EMS 20 can acquire the detection result of the power detection unit D (more specifically, the sensor 11d and the like).

  Hereinafter, an example of a power supply mode in the power supply system 1 configured as described above will be described with reference to FIGS. 3 and 4.

  In the present embodiment, the condominium divides a plurality of residences H into a plurality of groups, but in the following description, for convenience, the first group G1, the second group G2, and the M group Gm It shall be divided into two groups. Moreover, the 1st group G1, the 2nd group G2, and the Mth group Gm shall have three residences as the some residence H, respectively. Also, the names used in the above description are used as they are without substituting numbers for “M” and “n”.

  In FIG. 3, it is assumed that the total power load (hereinafter simply referred to as “power load”) of the residence 11, the residence 12, and the residence 1n of the first group G1 is 1800W. It is assumed that the power load of the second group G2 of the residence 21, the residence 22, ..., the residence 2n is 2400W. In addition, it is assumed that the power load of the residence M1, the residence M2, and the residence Mn of the Mth group Gm is 2100W.

  In the example shown in FIG. 3, the three fuel cell systems F of the housing 11, the housing 12 and the housing 1n of the first group G1 have a total generated power of 2100 W, so that the power load of the first group G1 300 W surplus.

  In addition, the three fuel cell systems F of the second group G2, the residence 21, the residence 22, and the residence 2n have a total generated power of 2100 W, so that the power load of the second group G2 is insufficient by 300 W. .

  In addition, the three fuel cell systems F of the housing M1, the housing M2, and the housing Mn of the Mth group Gm have a total generated power of 2100 W, so there is no excess or deficiency with respect to the power load of the Mth group Gm. Become.

  In such a case, surplus power (300 W) of the three fuel cell systems F of the first group G1 flows upstream, and flows into the electric circuit L2 via the electric circuit L1 and the electric circuit L1a. In this way, the surplus power (300 W) that has flowed into the electric circuit L2 covers the power that the three fuel cell systems F of the second group G2 lack for the power load.

  Thus, in the example shown in FIG. 3, the total generated power of all the fuel cell systems F of the first group G1, the second group G2, and the Mth group Gm is the first group G1, the second group G2, and the Mth group. Since it is equal to the total power load of the group Gm, power is not purchased from the system power supply 100 or is not sold to the system power supply 100.

  Thus, in the electric power supply system 1, the fuel cell system F of each residence H of the 1st group G1, the fuel cell system F of each residence H of the 2nd group G2, and each residence H of the M group Gm The power generated by the fuel cell system F can be used not only in the residence H that owns the fuel cell system F but also in other residences H (can be accommodated in other residences H).

  Next, in FIG. 4, it is assumed that the power load of the residence 11, the residence 12, and the residence 1n of the first group G1 is 1800W. It is assumed that the power load of the second group G2 of the residence 21, the residence 22, ..., the residence 2n is 2400W. Moreover, the electric power load of the residence M1, the residence M2, and the residence Mn of the Mth group Gm shall be 1000W.

  In the example shown in FIG. 4, the three fuel cell systems F of the first group G1 have a surplus of 300 W with respect to the power load of the first group G1 because the total generated power is 2100 W.

  In addition, the three fuel cell systems F of the second group G2, the residence 21, the residence 22, and the residence 2n have a total generated power of 2100 W, so that the power load of the second group G2 is insufficient by 300 W. .

  In addition, the three fuel cell systems F of the residence M1, the residence M2 and the residence Mn of the Mth group Gm have a total generated power of 2100W, so that 1100W surplus will be surpassed with respect to the power load of the Mth group Gm. .

  In such a case, surplus power (1100 W) of the three fuel cell systems F of the M-th group Gm flows upstream, a part flows from the electric circuit L1a to the electric circuit L2, and a remaining part of the electric circuit L1a. Flows into the electric circuit L1 and flows to the system power supply 100 side. In this way, a part of surplus power (300 W) that has flowed into the electric circuit L2 covers the power that the three fuel cell systems F of the second group G2 lack for the power load. Further, the remaining part of the surplus power (800) that has flowed to the system power source 100 side is the system power source 100 as power (1100 W) combined with surplus power (300 W) of the three fuel cell systems F of the first group G1. The power will be sold.

  Thus, in the example shown in FIG. 4, the total generated power of all the fuel cell systems F of the first group G1, the second group G2, and the Mth group Gm is the first group G1, the second group G2, and the Mth group. Since it is larger than the total power load of the group Gm, a part of the generated power is sold (reverse power flow) to the system power supply 100.

  Here, there is a case where the generated power of the fuel cell system F does not want to flow backward to the system power supply 100. For example, even when the power is reversely flowed (sold) to the system power supply 100, the price for the reversely flowed power cannot be obtained from the power company. In such a case, the residence H that owns the fuel cell system F (the resident of the residence H) is disadvantageous because the generated power is not effectively utilized despite the burden of city gas costs (utility costs). It becomes.

  Therefore, in the power supply system 1, by performing control for reducing the reverse power flow from the fuel cell system F to the system power supply 100 (hereinafter referred to as “reverse power flow suppression control”), the residents of the residence H can be prevented. Preventing profits.

  Below, the process of EMS20 in the case of performing the process of the reverse power flow suppression control which concerns on 1st embodiment using the flowchart of FIGS. 5-7 is demonstrated.

  The reverse power flow suppression control is executed by appropriately switching the mode of the storage battery system B to the eco mode or the stop mode. In the following, it is assumed that the storage battery system B is in the stop mode as an initial setting. That is, the storage battery system B is neither charged nor discharged in the initial setting.

  First, in step S101, the EMS 20 checks the overall power usage status of the power supply system 1, the operating state of each storage battery system B, and the remaining battery level of each storage battery system B. The remaining battery level of the storage battery system B refers to the amount of power remaining in the battery of the storage battery system B. EMS20 performs the process of step S102, after performing the process of step S101.

  In step S102, the EMS 20 determines whether or not it is in a power purchase state (whether or not power is supplied from the system power supply 100). If the EMS 20 determines that it is in a power purchase state based on the detection result of the sensor Dd (step S102: YES), the EMS 20 executes the process of step S103. On the other hand, if the EMS 20 determines that it is not in the power purchase state based on the detection result of the sensor Dd (step S102: NO), the process of step S105 is executed.

  In step S103, the EMS 20 determines whether all the storage battery systems B are in a discharged state. When it is determined that all the storage battery systems B are in a discharged state (step S103: YES), the EMS 20 ends the reverse power flow suppression control process.

  In this case, since there is no storage battery system B that can newly start discharging, the power purchase state is continued.

  On the other hand, in step S103, when EMS20 determines with all the storage battery systems B not being a discharge state (step S103: NO), it performs the process of step S104.

  In step S104, the EMS 20 determines whether or not the remaining battery levels of all the storage battery systems B that are not in the discharged state are minimum. In addition, the battery remaining amount is the state where the battery remaining amount of the storage battery system B is equal to or less than an arbitrary specified value at which discharge becomes impossible. If the EMS 20 determines that the remaining battery levels of all the storage battery systems B that are not in the discharged state are the minimum (step S104: YES), the process of the reverse power flow suppression control ends.

  In this case, since there is no storage battery system B that can newly start discharging, the power purchase state is continued.

  On the other hand, in step S104, when EMS20 determines with the battery remaining charge of all the storage battery systems B which are not a discharge state being the minimum (step S104: NO), it performs the process of step S121.

  In this case, although one of the storage battery systems B has a remaining battery level to the extent that it can be discharged, it is in the stop mode, so that no discharge is performed and power is purchased (power is supplied from the system power supply 100). It is assumed that Therefore, in the processing after step S121, the EMS 20 changes one of the storage battery systems B to the eco mode in order to cover the power supplied from the grid power supply 100 with the discharge power of the storage battery system B.

  In step S121, the EMS 20 determines whether or not the storage battery system Bb is in a discharged state. When it is determined that the storage battery system Bb is in a discharged state (step S121: YES), the EMS 20 executes the process of step S122. On the other hand, when the EMS 20 determines that the storage battery system Bb is not in a discharged state (step S121: NO), the EMS 20 executes the process of step S124.

  In step S124, the EMS 20 determines whether or not the remaining battery level of the storage battery system Bb is minimum. If the EMS 20 determines that the remaining battery level of the storage battery system Bb is not the minimum (step S124: NO), the EMS 20 executes the process of step S125. On the other hand, when the EMS 20 determines that the remaining battery level of the storage battery system Bb is the minimum (step S124: YES), the EMS 20 executes the process of step S122.

  In step S125, the EMS 20 switches the mode of the storage battery system Bb to the eco mode. After executing the process of step S125, the EMS 20 ends the reverse power flow suppression control process.

  Thus, when the storage battery system Bb is not in a discharged state (step S121: NO) and the remaining battery level of the storage battery system Bb is not minimum (step S124: NO), the extent to which the storage battery system Bb can be discharged. In spite of having a remaining battery capacity, it is assumed that no discharge is performed because of the stop mode. Therefore, the storage battery system Bb can switch the mode to the eco mode (step S125). Thus, the storage battery system Bb is preferentially discharged as compared with the storage battery systems B for other groups, and can maintain a state where the remaining battery capacity is low (charge capacity is kept open).

  On the other hand, when the storage battery system Bb is in a discharged state (step S121: YES) or when the remaining battery level of the storage battery system Bb is minimum (step S124: YES), the storage battery system Bb is newly discharged. Therefore, one of the storage battery systems B for the group is changed to the eco mode instead of the storage battery system Bb.

  In step S122, the EMS 20 determines whether or not there is a storage battery system B in the stop mode and in a power purchase state among the storage battery systems B for groups (storage battery systems B provided one by one in a plurality of groups). judge.

  In addition, the storage battery system B in a power purchase state refers to the storage battery system B in which power flows to the power load side (downstream side) at the connection portion between the storage battery system B and the electric circuit. That is, the fact that there is a storage battery system B in a power purchase state indicates that the generated power of the fuel cell system F is insufficient with respect to the residence H (electric power load) connected to the downstream side of the storage battery system B. Yes.

  In Step S122, when it is determined that the storage battery system B for the group has the storage battery system B in the stop mode and in the power purchase state (Step S122: YES), the EMS 20 executes the process of Step S123.

  In step S123, the EMS 20 switches the mode of the storage battery system B having the maximum remaining battery power to the eco mode among the storage battery systems B in the stop mode and the power purchase state in the group storage battery system B. EMS20 complete | finishes the process of reverse power flow suppression control, after performing the process of step S123.

  Thus, in the storage battery system B for groups, when there is the storage battery system B in the stop mode and in the power purchase state (step S122: YES), the storage battery system B is not discharged, so It is assumed that it is in a state (a state where power is supplied from the system power supply 100). Therefore, the process of step S123 is performed to start the discharge of the storage battery system B, thereby eliminating the power purchase state. At this time, since the discharge is started from the storage battery system B for the group having the largest remaining battery capacity, the remaining battery capacity of the plurality of storage battery systems B can be equalized.

  Here, with reference to FIGS. 8 and 9, an example of a power supply mode in a power purchase state (a state in which power is supplied from the system power supply 100) will be described.

  In the following drawings, (%) illustrated on the storage battery system B indicates the amount of remaining battery capacity of the storage battery system B. In addition, 10% illustrated on the storage battery system Bb indicates that the battery remaining amount is the minimum. Further, in the subsequent drawings, an electric circuit through which no electric power flows is illustrated by a broken line for convenience.

  In the example shown in FIG. 8, 300 W of power is purchased from the system power supply 100. Further, the generated power of the three fuel cell systems F of the first group G1 is surplus by 300 W. Thus, the power purchased from the system power supply 100 (300 W) and the surplus power (300 W) of the three fuel cell systems F of the first group G1 are combined and flow into the electric circuit L1a.

  In such a case, the storage battery system Bb is not in a discharged state (step S121: NO), and the remaining battery level of the storage battery system Bb is minimal (step S124: YES). Then, it is determined whether or not there is a storage battery system B in the stop mode and in the power purchase state (step S122). Here, referring to FIG. 8, the storage battery system 2b of the second group G2 and the storage battery system Mb of the Mth group Gm are in the stop mode and in the power purchase state.

  Therefore, when comparing the remaining battery levels of the storage battery system 2b of the second group G2 and the storage battery system Mb of the Mth group Gm, the storage battery system 2b (with a remaining battery level of 80%) is more storage battery (with a remaining battery level of 70%). The remaining battery level is larger than that of the system Mb. That is, the storage battery system 2b is the storage battery system B in the stop mode and in the power purchase state, and the remaining battery level is maximum. Thus, the storage battery system 2b is changed from the stop mode to the eco mode (step S123).

  When the storage battery system 2b is changed from the stop mode to the eco mode, discharging is started based on the load following function. Specifically, the storage battery system 2b acquires the magnitude of the power flowing through the connection part between the storage battery system 2b and the electric circuit L2 based on the detection result of the sensor 2d. Thus, the storage battery system 2b discharges 300 W corresponding to the power flowing through the connection portion based on the load following function.

  As a result, as shown in FIG. 9, the power load of the second group G2 is covered by the generated power of the three fuel cell systems F of the second group G2 and the discharged power of the storage battery system 2b. Further, the surplus power (300 W) of the three fuel cell systems F of the first group G1 flows into the electric circuit Lm from the electric circuit L1a, and the three fuel cell systems F of the Mth group Gm are insufficient for the power load. Will be covered.

  As described above, in the example shown in FIGS. 8 and 9, the reverse power flow suppression control is executed to prevent power from being purchased from the system power supply 100 or sold to the system power supply 100. Yes. At this time, since the discharge is performed from the group storage battery system B (storage battery system 2b) having the largest remaining battery capacity, the remaining battery capacity of the plurality of storage battery systems B can be equalized.

  In step S122, when the EMS 20 determines that there is no storage battery system B in the stop mode and in the power purchase state in the group storage battery system B (step S122: NO), the process of step S126 is executed.

  In step S126, the EMS 20 determines whether or not there is a charged storage battery system B among all the storage battery systems B (storage battery system Bb and group storage battery system B). If it is determined that there is a storage battery system B in a charged state among all the storage battery systems B (step S126: YES), the EMS 20 executes the process of step S127.

  In step S127, among all the storage battery systems B, the EMS 20 switches the mode of the storage battery system B having the maximum remaining battery power to the stop mode among the storage battery systems B in the charged state. EMS20 complete | finishes the process of reverse power flow suppression control, after EMS20 performs the process of step S127.

  Thus, there is no storage battery system B in the stop mode and in the power purchase state among the storage battery systems B for the group (step S122: NO), and the storage battery system B in the charged state among all the storage battery systems B In some cases (step S126: YES), it is assumed that the storage battery system B in the charged state is in a power purchase state (a state in which power is supplied from the system power supply 100). Therefore, the process of step S127 is performed to stop the charging of the storage battery system B, thereby eliminating the power purchase state. At this time, since the charging is stopped from the storage battery system B having the largest remaining battery level, the remaining battery levels of the plurality of storage battery systems B can be equalized.

  On the other hand, in Step S126, when it is determined that there is no charged storage battery system B among all the storage battery systems B (Step S126: NO), the EMS 20 ends the reverse power flow suppression control process.

  Thus, there is no storage battery system B in the stop mode and in the power purchase state among the storage battery systems B for the group (step S122: NO), and the storage battery system B in the charged state among all the storage battery systems B If not (step S126: NO), the power purchase state (the state in which power is supplied from the system power supply 100) is not performed for charging the storage battery system B (for example, the entire power load is the fuel cell system). It is assumed that it is larger than the total generated power of F). Therefore, the storage battery system B does not change the mode.

  Next, in step S105, which is executed when it is determined that the power is not being purchased (a state where power is being supplied from the system power supply 100) (step S102: NO), the EMS 20 is in a power selling state (system power supply). Whether power is being supplied to 100). If the EMS 20 determines that it is not in the power sale state based on the detection result of the sensor Dd (step S105: NO), the process of the reverse power flow suppression control ends. On the other hand, when the EMS 20 determines that it is in the power sale state based on the detection result of the sensor Dd (step S105: YES), the process of step S106 is executed.

  In step S106, the EMS 20 determines whether all the storage battery systems B are in a charged state. When it is determined that all the storage battery systems B are in the charged state (step S106: YES), the EMS 20 ends the reverse power flow suppression control process.

  In this case, since there is no storage battery system B that can newly start charging, the power sale state is continued.

  On the other hand, when it is determined in step S106 that all the storage battery systems B are not in the charged state (step S106: NO), the process of step S107 is executed.

  In step S107, the EMS 20 determines whether or not the remaining battery levels of all the storage battery systems B are maximum. Note that the maximum remaining battery level indicates a state in which the remaining battery level of the storage battery system B is equal to or greater than an arbitrary specified value at which charging is not possible. If the EMS 20 determines that the remaining battery power of all the storage battery systems B is the maximum (step S107: YES), the reverse power flow suppression control process ends.

  In this case, since there is no storage battery system B that can newly start charging, the power sale state is continued.

  On the other hand, in Step S107, when EMS20 determines with the battery remaining charge of all the storage battery systems B not being the maximum (step S107: NO), it performs the process of Step S131.

  In step S131, the EMS 20 determines whether or not there is a discharged storage battery system B among all the storage battery systems B. If it is determined that there is a storage battery system B in a discharged state among all the storage battery systems B (step S131: YES), the EMS 20 executes the process of step S132.

  In step S132, the EMS 20 switches the mode of the storage battery system B that has the least remaining battery among the storage battery systems B that are in a discharged state among all the storage battery systems B to the stop mode. EMS20 complete | finishes the process of reverse power flow suppression control, after EMS20 performs the process of step S132.

  In this case, it is assumed that the storage battery system B in a discharged state is in a power selling state (a state where power is supplied to the system power supply 100). Therefore, the process of step S132 is performed to stop the discharge of the storage battery system B, thereby eliminating the power sale state. At this time, since the discharge is stopped from the storage battery system B having the smallest remaining battery level, the remaining battery levels of the plurality of storage battery systems B can be equalized.

  On the other hand, when it is determined in step S131 that there is no discharged storage battery system B among all the storage battery systems B (step S131: NO), the EMS 20 executes the process of step S133.

  In step S133, the EMS 20 determines whether or not the storage battery system Bb is in a charged state. When it is determined that the storage battery system Bb is in a charged state (step S133: YES), the EMS 20 ends the reverse power flow suppression control process.

  In this case, it is assumed that the storage battery systems B for all groups other than the storage battery system Bb are also charged. That is, since the charging power to the storage battery system B cannot be increased any more, the power sale state is continued.

  On the other hand, in step S133, when the EMS 20 determines that the storage battery system Bb is not in a charged state (step S133: NO), the process of step S134 is executed.

  In step S134, the EMS 20 determines whether or not the storage battery systems B for all groups are in a charged state. When it is determined that the storage battery system B for all groups is in a charged state (S134: YES), the EMS 20 executes the process of step S135.

  In step S135, the EMS 20 switches the mode of the storage battery system Bb to the eco mode. After executing the process of step S125, the EMS 20 ends the reverse power flow suppression control process.

  In this case, since all the storage battery systems B for the group are in a charged state, the charging power to the storage battery system B for the group cannot be increased any more. Therefore, in order to cancel the power sale state, the storage battery system Bb is changed from the stop mode to the eco mode. Thus, since the storage battery system Bb is in the charged state, the power sale state can be eliminated. In this way, the storage battery system Bb is set so that the storage battery system B for all groups is finally charged.

  On the other hand, when it is determined in step S134 that the storage battery systems B for all groups are not in the charged state (S134: NO), the EMS 20 executes the process of step S136.

  In step S136, the EMS 20 determines whether or not there is a storage battery system B in the stop mode and in the power sale state in the group storage battery system B.

  In addition, the storage battery system B in the power sale state refers to the storage battery system B in which power flows to the system power supply 100 side (upstream side) at the connection portion between the storage battery system B and the electric circuit. That is, the presence of the storage battery system B in the power sale state indicates that the generated power of the fuel cell system F is surplus with respect to the residence H (electric power load) connected to the downstream side of the storage battery system B. Yes.

  In step S136, when EMS20 determines with the storage battery system B for groups having the storage battery system B of a stop mode and a power sale state (step S136: YES), it performs the process of step S137.

  In step S137, among the storage battery systems B for the group, the EMS 20 switches the mode of the storage battery system B with the smallest remaining battery power among the storage battery systems B in the stop mode and the power sale state to the eco mode. EMS20 complete | finishes the process of reverse power flow suppression control, after performing the process of step S137.

  As described above, when there is the storage battery system B in the stop mode and in the power sale state among the storage battery systems B for the group (step S136: YES), the storage battery system B is not charged and sold. It is assumed that it is in an electric state (a state where electric power is supplied from the system power supply 100). Therefore, the process of step S137 is performed to start the charging of the storage battery system B, thereby eliminating the power sale state. At this time, since charging is started from the storage battery system B for the group having the smallest remaining battery capacity, the remaining battery capacity of the plurality of storage battery systems B can be equalized.

  On the other hand, when the EMS 20 determines that there is no storage battery system B in the stop mode and in the power sale state in the storage battery system B for the group (step S136: NO), the process of the reverse power flow suppression control is ended. .

  Here, an example of a power supply mode in the power sale state (a state where power is supplied to the system power supply 100) will be described with reference to FIGS. 4 and 10 to 12. FIG.

  As described above, in the example shown in FIG. 4, 1100 W of power is sold. In this example, there is no storage battery system B in a discharged state among all storage battery systems B (step S131: NO), the storage battery system Bb is not in a charged state (step S133: NO), and for all groups Since the storage battery system B is not in the charged state (step S134: NO) and there is the storage battery system B in the stop mode and in the power sale state among the group storage battery systems B (step S136: YES), the stop mode and the sale Among the storage battery systems B for the group in the electric state, the mode of the storage battery system B with the smallest remaining battery level is switched to the eco mode (step S137).

  Here, in the example shown in FIG. 4, among the storage battery systems B (specifically, the storage battery system 1b and the storage battery system Mb) for the group in the stop mode and the power sale state, the storage battery system 1b has a remaining battery level. The minimum (60%) (see FIG. 10). Therefore, as shown in FIG. 10, the storage battery system 1b is switched to the eco mode, and charging of the storage battery system 1b is started.

  Thus, as shown in FIG. 10, the storage battery system 1b charges the surplus power (300 W) of the three fuel cell systems F of the first group G1. That is, although it decreased from 1100W, the power sale of 800W is still performed and the power sale state is continuing.

  In such a case, the same processing as described above (step S131: NO, step S133: NO, step S134: NO, step S136: YES, step S137) is performed, and the mode of the storage battery system Mb next to the storage battery system 1b. Is switched to the eco mode (step S137). In this way, the storage battery system Mb is switched to the eco mode, and charging of the storage battery system Mb is started.

  Thus, as shown in FIG. 11, the storage battery system Mb charges the surplus power (1100 W) of the three fuel cell systems F of the Mth group GM. That is, the power sale state is canceled and the next power purchase is performed for 300 W, so that the power purchase state is entered.

  In such a case, since the storage battery system Bb is not in a discharged state (step S121: NO), and the remaining battery level of the storage battery system Bb is not minimum (step S124: NO), the mode of the storage battery system Bb is switched to the eco mode. (Step S125).

  Thus, when the storage battery system Bb is changed from the stop mode to the eco mode, discharging is started based on the load following function. Specifically, first, the storage battery system Bb acquires the magnitude of power flowing through the connection portion between the storage battery system Bb and the electric circuit L1 based on the detection result of the sensor Dd. Thus, the storage battery system Bb discharges 300 W corresponding to the power flowing through the connection portion based on the load following function.

As described above, the power supply system 1 according to the first embodiment of the present invention is
A plurality of branch circuits (parts on the downstream side of the circuit L1, the circuits L2 and the like) that are part of the circuit connecting the system power source 100 and the power load and are branched from each other and connected to the power load (residence H) Electric circuit Lm),
A storage battery system B for a group provided corresponding to each power load and connected to each corresponding power load via each branch circuit,
A fuel cell system F connected between each power load and a storage battery system B for each group corresponding to each power load;
A power detector D capable of detecting power flowing to the system power supply 100;
EMS 20 (control unit) for controlling the operation of the storage battery system B for the group based on the detection result of the power detection unit D;
Comprising
The EMS 20 (control unit)
When power flowing to the system power supply 100 is detected (step S102: NO),
Extracting the storage battery system B for the group in a discharged state from the storage battery system B for the group connected to the power loads,
Among the storage battery systems B for the group in the extracted discharge state, the discharge state is stopped in ascending order of remaining battery power (step S131: YES, step S132).

With such a configuration, a plurality of storage battery systems B (group storage battery system B) can be provided, and these storage battery systems B can be suitably operated.
Specifically, when the storage battery system B in a discharged state is in a power sale state (a state in which power is supplied to the system power supply 100), by stopping the discharge of the storage battery system B, the power sale state Can be eliminated.
In this way, since the power sale state can be canceled when power is being sold, for example, even when power is reversely flowed (sold) to the system power supply 100, the reversely flowed power It is possible to prevent wasteful power generation using city gas (fuel) in the case where the price for the power is not obtained from the electric power company.
At this time, since the discharge is stopped from the storage battery system B having the smallest remaining battery level, the remaining battery levels of the plurality of storage battery systems B can be equalized.

In the power supply system 1,
The battery further includes a storage battery system Bb connected to an electric circuit (a portion on the upstream side of the electric circuit L1) connecting the plurality of branch electric circuits and the system power supply 100,
When all the storage battery systems B for the group connected to the power loads are in a charged state, the storage battery system Bb is charged (step S134: YES, step S135).

With such a configuration, when the storage battery systems B for all groups are in a charged state, charging of the storage battery system Bb can be started. In this way, when the group storage battery system B cannot be charged any more, the power sale state can be eliminated by charging the storage battery system Bb.
In addition, the storage battery system Bb has a lower priority for charging than the storage battery systems B for all groups. In this way, the storage battery system Bb can maintain a state in which the remaining battery level is low (leave a charge capacity open) as compared to the storage battery systems B for all groups. That is, the storage battery system Bb can prevent the surplus power from flowing to the system power source 100 when the generated power of the group fuel cell system F is surplus, for example, and functions as a final defense means. Can be fulfilled.

In the power supply system 1,
The storage battery for the group in which charging / discharging is stopped in the storage battery system B for the group connected to each of the power loads, and the power flows to the system power supply 100 side through the connection portion with the branch electric circuit. When there is a system B (step S136: YES),
In the storage battery system B for the group in which electric power is flowing to the system power supply 100 side through the connection part with the branch electric circuit, the battery is charged in order from the lowest remaining battery (step S137).

With such a configuration, when charging / discharging of the storage battery system B for the group is stopped, the storage battery system for the group is in a power sale state (a state where power is supplied to the system power supply 100). By starting the charging of B, it is possible to eliminate the power sale state.
At this time, since the charging is started from the storage battery system B having the smallest remaining battery level, the remaining battery levels of the plurality of storage battery systems B can be equalized.

In the power supply system 1,
The battery further includes a storage battery system Bb connected to an electric circuit (a portion on the upstream side of the electric circuit L1) connecting the plurality of branch electric circuits and the system power supply 100,
The power detection unit D is capable of detecting power flowing from the system power supply 100,
The EMS 20 (control unit)
When power flowing from the system power supply 100 is detected,
The storage battery system Bb is discharged (step S121: NO, step S125).

With such a configuration, it is possible to eliminate the power purchase state by discharging the storage battery system Bb.
In addition, the storage battery system Bb has a higher priority for discharging than the storage battery systems B for all groups. In this way, the storage battery system Bb can maintain a state in which the remaining battery level is low (leave a charge capacity open) as compared to the storage battery systems B for all groups. That is, the storage battery system Bb can prevent the surplus power from flowing to the system power source 100 when the generated power of the group fuel cell system F is surplus, for example, and functions as a final defense means. Can have.

In the power supply system 1,
When the storage battery system Bb is in a discharged state and there is the storage battery system B for the group in which power is flowing to the power load side through the connection with the branch electric circuit (step S121: YES, step S122: YES),
In the storage battery system B for the group in which power is flowing to the power load side through the connecting portion with the branch electric circuit, the battery is discharged in order from the highest remaining battery level (step S123).

With such a configuration, when the storage battery system B for the group is not discharged, the power storage state (the state where power is supplied from the system power supply 100) is set, so that the storage battery system B for the group By starting the discharge, the power purchase state can be eliminated.
At this time, since the discharge is started from the storage battery system B having the largest remaining battery level, the remaining battery levels of the plurality of storage battery systems B can be equalized.

In the power supply system 1,
When the storage battery system Bb is in a discharged state and there is no storage battery system B for the group in which power is flowing to the power load side through the connection with each branch circuit (step S122: NO) ,
Among the storage battery systems B for the group connected to the power loads, extract the storage battery system B for the group in a charged state,
In the extracted storage battery system B for the group, the charging state is stopped in descending order of the remaining battery level (step S126: YES, step S127).

With such a configuration, when the storage battery system B in a charged state is in a power purchase state (a state in which power is supplied from the system power supply 100), by stopping charging of the storage battery system B, a power purchase state Can be eliminated.
At this time, since the charging is stopped from the storage battery system B for the group having the largest remaining battery capacity, the remaining battery capacity of the plurality of storage battery systems B can be equalized.

  Although one embodiment has been described above, the present invention is not limited to the above-described configuration, and various modifications can be made within the scope of the invention described in the claims.

  For example, although the object into which the power supply system 1 is introduced is an apartment, the present invention is not limited to this. An object to which the power supply system 1 is introduced may be an office building, a hospital, a school, or the like.

  Further, the control unit is not limited to EMS (energy management system), and various types of devices such as a control unit of the fuel cell system F can be used.

  Further, the EMS 20 may be electrically connected to each fuel cell system F as shown in FIG. In this case, the EMS 20 is configured to be able to output a predetermined signal to each fuel cell system F. Thus, the EMS 20 can control the operation of each fuel cell system F. Further, the EMS 20 is configured to be able to input a predetermined signal from each fuel cell system F. Thus, the EMS 20 can acquire information regarding the operation of each fuel cell system F.

  Specifically, the EMS 20 can acquire information regarding whether or not the power generation operation of each fuel cell system F is currently stopped for reasons such as maintenance. Further, the EMS 20 may perform reverse power flow suppression control processing using information regarding whether or not the power generation operation of each fuel cell system F is stopped. A description will be given below.

  Below, the process of EMS20 in the case of performing the process of the reverse power flow suppression control which concerns on 2nd embodiment using the flowchart of FIGS. 14-16 is demonstrated.

  In the process of reverse power flow suppression control according to the second embodiment, the difference from the process of reverse power flow suppression control according to the first embodiment is that EMS 20 relates to whether or not the power generation operation of each fuel cell system F is stopped. It is a point to use information.

  Specifically, in step S201 shown in FIG. 14 (corresponding to step S101 according to the first embodiment), the EMS 20 includes the overall power usage status of the power supply system 1, the operating state of each storage battery system B, and Not only the remaining battery level of each storage battery system B but also the power generation state of each fuel cell system F is confirmed.

  And in step S222 (equivalent to step S122 which concerns on 1st embodiment) shown in FIG. 15, EMS20 is in the storage battery system B for groups (the storage battery system B provided one each in several groups). Then, it is determined whether there is the storage battery system B in the stop mode and in the power purchase state and the fuel cell system F is in the power generation state.

  The EMS 20 includes a storage battery system B that is in a stop mode and in a power purchase state among the storage battery systems B for groups (storage battery systems B provided one by one in a plurality of groups), and the fuel cell system F generates power. When it determines with it being in a state (step S222: YES), the process of step S223 (equivalent to step S123 which concerns on 1st embodiment) is performed.

  In step S223, the EMS 20 is the storage battery system B having the maximum remaining battery power among the storage battery systems B in the stop mode and the power purchase state in the group storage battery system B and in which the fuel cell system F is in the power generation state. Switch B mode to Eco mode. EMS20 complete | finishes the process of reverse power flow suppression control, after performing the process of step S223.

  In addition, the EMS 20 includes a storage battery system B in a stop mode and in a power purchase state among the storage battery systems B for groups (one storage battery system B provided for each of a plurality of groups), and the fuel cell system F generates power. When it determines with it not being a state (step S222: NO), the process of step S226 (equivalent to step S126 which concerns on 1st embodiment) is performed.

  In step S226, the EMS 20 determines whether or not the fuel cell system F is in a power generation state and there is a charged storage battery system B among all the storage battery systems B (storage battery system Bb and group storage battery system B). judge. When the EMS 20 determines that the fuel cell system F is in a power generation state and there is a charged storage battery system B among all the storage battery systems B (step S226: YES), the EMS 20 executes the process of step S127.

  In contrast, in step S226, the EMS 20 determines that the fuel cell system F is in the power generation state and that there is no charged storage battery system B among all the storage battery systems B (step S226: NO), the reverse power flow suppression control process is terminated.

  Further, in step S231 shown in FIG. 16 (corresponding to step S131 according to the first embodiment), the EMS 20 is a storage battery system in which the fuel cell system F is in a power generation state and is in a discharge state among all the storage battery systems B. It is determined whether or not B exists. When the EMS 20 determines that the fuel cell system F is in a power generation state and that there is a discharged storage battery system B among all the storage battery systems B (step S131: YES), (step S132 according to the first embodiment) The process of step S232 is executed.

  In step S232, the EMS 20 stops the mode of the storage battery system B in which the fuel cell system F is in the power generation state among the storage battery systems B that are in the discharge state among all the storage battery systems B, and the battery remaining amount is the minimum. Switch to mode. EMS20 complete | finishes the process of reverse power flow suppression control, after EMS20 performs the process of step S232.

  Note that when the EMS 20 determines that the fuel cell system F is in a power generation state and that there is no discharged storage battery system B among all the storage battery systems B (step S231: NO), the process of step S133 is performed. Execute.

  Further, the EMS 20 is executed after the process of step S134 (corresponding to step S136 according to the first embodiment). In step S236, the fuel cell system F is in the power generation state, and the group storage battery system B Thus, it is determined whether or not there is a storage battery system B in the stop mode and in the power sale state. When the EMS 20 determines that the fuel cell system F is in the power generation state and the storage battery system B for the group has the storage battery system B in the stop mode and the power sale state (step S236: YES), the step The process of S137 is executed. On the other hand, when the EMS 20 determines that the fuel cell system F is in the power generation state and that there is no storage battery system B in the stop mode and in the power sale state among the group storage battery systems B (step S236: NO) ), The reverse power flow suppression control process is terminated.

  With such a configuration, in the processing of the reverse power flow suppression control according to the second embodiment, information on whether or not the power generation operation of each fuel cell system F is stopped, for example, a reverse power flow occurs. In this case, it can be obtained as information that the reverse power flow is performed by the power generated by the fuel cell system F. That is, for example, when a reverse power flow occurs due to some abnormal situation, it is possible to prevent switching of the mode of the storage battery system B without noticing the abnormal situation.

As described above, the power supply system 1 according to the second embodiment of the present invention is
The EMS 20 (control unit)
Information on the power generation state of the fuel cell system F can be obtained;
The control of the EMS 20 (control unit) is performed based on information on the power generation state in addition to the detection result of the power detection unit D.

  With such a configuration, for example, when a reverse power flow occurs due to some abnormal situation, it is possible to prevent the storage battery system B from being controlled without noticing the abnormal situation.

DESCRIPTION OF SYMBOLS 1 Electric power supply system 20 Control part 100 System power supply B Storage battery system D Electric power detection part F Fuel cell system H Housing

Claims (7)

A part of the electric circuit connecting the system power supply and the load, and a plurality of branch electric circuits branched from each other and connected to the load,
A first storage battery system provided corresponding to each load, and connected to each corresponding load via each branch circuit;
A fuel cell system connected between each load and each first storage battery system corresponding to each load;
A detection unit capable of detecting the power flowing to the system power supply;
A control unit for controlling the operation of the first storage battery system based on the detection result of the detection unit;
Comprising
The controller is
If power flowing to the grid power supply is detected,
Of the first storage battery system connected to each load, extract the first storage battery system in a discharged state,
Of the first storage battery system in the extracted discharge state, the discharge state is stopped in the order of the remaining battery level,
A power supply system characterized by that. Further comprising a second storage battery system connected to a circuit connecting the plurality of branch circuits and the system power supply,
The controller is
The operation of the second storage battery system can be controlled based on the detection result of the detection unit,
When all the first storage battery systems connected to the loads are in a charged state, the second storage battery system is in a charged state.
The power supply system according to claim 1. When there is the first storage battery system in which charging and discharging are stopped in the first storage battery system connected to each of the loads, and power is flowing to the system power supply side through a connection portion with the branch circuit Is
Of the first storage battery system in which power is flowing to the system power supply side through the connection with the branch electric circuit, the charging state is set in ascending order of the remaining battery level.
The power supply system according to claim 1 or 2. Further comprising a second storage battery system connected to a circuit connecting the plurality of branch circuits and the system power supply,
The detection unit can detect the power flowing from the system power supply,
The controller is
If power flowing from the grid power source is detected,
The second storage battery system is in a discharged state,
The power supply system according to any one of claims 1 to 3. When the second storage battery system is in a discharged state and there is the first storage battery system in which power is flowing to the load side through the connection with the branch circuit,
Of the first storage battery system in which power is flowing to the load side through the connecting portion with the branch electric circuit, the battery is in a discharged state in descending order of remaining battery power.
The power supply system according to claim 4. In the case where the second storage battery system is in a discharged state and there is no first storage battery system in which power is flowing to the load side through a connection portion with each branch circuit,
Among the first storage battery systems connected to each load, extract the first storage battery system in a charged state,
Among the first storage battery systems in the extracted charging state, the charging state is stopped in order of the remaining battery level,
The power supply system according to claim 5. The controller is
It is possible to obtain information on the power generation state of the fuel cell system,
In addition to the detection result of the detection unit, the control of the control unit is performed based on information on the power generation state.
The power supply system according to any one of claims 1 to 6.

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