Emergency power supply system combining storage battery built-in charger and solar power generation facility

Abstract

To effectively utilize a plurality of storage batteries built in a charger to balance the three factors of a residual capacity of a storage battery, power supply from sunlight and power supply to a load, that constantly fluctuate, and also to enable power supply to an emergency utility load during power failure.SOLUTION: An emergency power supply system comprises: a charger 40 in which a plurality of storage batteries (44A and 44B) are built in; charge / discharge control means (30A and 30B) installed for the respective storage batteries; a solar power generation facility 22; and means (70, 72 and 74) for switching combination of states of charge to the respective storage batteries (44A and 44B), states of discharge from the respective storage batteries (44A and 44B) and states of power supply to loads (60 and 62) in correspondence with a state of a power grid 10, a state of sunlight, and a residual capacity of the respective storage batteries (44A and 44B).SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to an emergency power supply system that combines a charger with a built-in storage battery and a solar power generation facility, and in particular to an emergency power supply system that is suitable for use in a system that uses a rapid charger for charging electric vehicles, and that effectively utilizes multiple storage batteries built into the charger to balance the constantly fluctuating remaining battery charge, power supply from sunlight, and power supply to the load, and that can also supply power to an emergency power load in the event of a power outage. [Background technology]

[0002] There is a demand for emergency power systems that support power resilience and business continuity plans (BCPs). However, installing large-capacity, expensive storage batteries specifically for BCPs is costly and has low investment effectiveness.

[0003] As an example of technology that combines solar power generation and storage batteries to create an emergency power source, as in the present invention, Patent Document 1 describes a disaster charging system that combines a solar cell module with a storage battery to enable charging of mobile terminals from the storage battery during a disaster power outage when power supply from commercial power sources is stopped, thereby enabling safety confirmation. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2023-38031 [Patent Document 2] Japanese Patent Application Laid-Open No. 2014-123475 [Patent Document 3] Japanese Patent Application Laid-Open No. 2012-151938 [Patent Document 4] Japanese Patent Application Laid-Open No. 2012-253952 [Patent Document 5] Japanese Patent Publication No. 2022-165089 [Patent Document 6] WO2022 / 224618A1 publication [Patent Document 7] Japanese Patent Application Publication No. 9-103033 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the technology described in Patent Document 1 is intended to supply small amounts of direct current for purposes such as charging mobile devices, and is not capable of supplying power to important emergency loads, including power loads that require a three-phase alternating current supply, such as mechanical parking lot drive motors, water supply lift pumps, and essential household appliances.

[0006] Meanwhile, Patent Document 2 describes a rapid charger for electric vehicles (EVs) equipped with a large-capacity storage battery. Patent Documents 3 and 4 also describe technology for using an EV rapid charger to level the load on electricity-consuming facilities such as convenience stores. However, no consideration has been given to combining an EV rapid charger with a solar power generation facility for use in an emergency power supply system.

[0007] Furthermore, Patent Documents 5, 6 and 7 describe storage battery systems having multiple storage batteries, but these are technologies related to charging and do not describe discharge in emergencies.

[0008] A single storage battery cannot be charged and discharged simultaneously. Therefore, particularly when simultaneously charging using solar power generation as a power source and supplying power to a load, as in the present invention, power supply from the power source depends on the amount of sunlight received, and so starts or stops regardless of the remaining battery charge or the power supply to the load. Systems capable of only charging or only discharging are unable to maintain an optimal balance between the constantly fluctuating remaining battery charge, the power supply from the sun, and the power supply to the load, resulting in problems such as the risk of overcharging or over-discharging the storage battery, ineffective use of solar power, and inability to supply power to the load in a timely manner.

[0009] The present invention has been made to solve the above-mentioned conventional problems, and its objective is to effectively utilize multiple storage batteries built into a charger to balance the constantly fluctuating remaining battery charge, power supply from sunlight, and power supply to the load, thereby making it possible to supply power to emergency power loads in the event of a power outage. [Means for solving the problem]

[0010] The present invention solves the above-mentioned problems by providing an emergency power supply system that combines a charger with built-in batteries and solar power generation equipment, characterized by comprising: a charger with multiple built-in batteries; charge / discharge control means provided for each battery; solar power generation equipment; and means for switching the combination of the charging state of each battery, the discharging state of each battery, and the power supply state to the load depending on the state of the power grid, the state of sunlight, and the remaining charge of each battery.

[0011] Here, in the event of a power outage when power cannot be received from the power grid, depending on the remaining battery charge and the state of sunlight, if at least one of the storage batteries has sufficient remaining battery charge, that storage battery will be discharged to the emergency load and power will be supplied from the solar power generation equipment, and if all of the storage batteries have insufficient remaining battery charge, discharging from the storage batteries to the emergency load will be stopped until charging of the storage batteries by the solar power generation equipment progresses.

[0012] The emergency loads may also include power loads that must operate even during a power outage.

[0013] The charger may also be a rapid charger for an electric vehicle equipped with a large-capacity storage battery.

[0014] In addition, both the solar power generation equipment and the charger can be installed in a parking lot.

[0015] Furthermore, the solar power generation facility may include solar panels arranged on the roof of a parking lot, and the charger may be arranged in the same parking lot.

[0016] Furthermore, during normal times when power can be received from the power grid, at least one of the storage batteries can be charged depending on the state of sunlight. [Effects of the Invention]

[0017] In this invention, multiple storage batteries are each provided with a charge / discharge control means, allowing one battery to be charged and another to be discharged simultaneously. Depending on the remaining battery charge and the power supply capacity to the load, it is also possible to charge or discharge all of the multiple storage batteries. This allows solar power generation to be always used to the maximum extent for charging and supplying to the load.

[0018] Therefore, according to the present invention, by effectively utilizing the multiple storage batteries built into the charger, it is possible to balance the constantly fluctuating remaining battery charge, the power supply from sunlight, and the power supply to the load, and it is also possible to supply power to an emergency power load in the event of a power outage.

[0019] Furthermore, costs can be reduced by using expensive, large-capacity storage batteries for both BCP and EV charging. [Brief explanation of the drawings]

[0020] [Figure 1] FIG. 1 is a block diagram showing a schematic configuration of an embodiment of the present invention. [Figure 2] FIG. 1 is a block diagram showing a detailed configuration of an embodiment of the present invention and connections under normal conditions. [Figure 3] Block diagram showing connections during a power outage [Figure 4] The same diagram showing normal operation [Figure 5] A diagram showing operation during a power outage DETAILED DESCRIPTION OF THE INVENTION

[0021] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the contents described in the following embodiments and examples. Furthermore, the constituent elements in the embodiments and examples described below include those that can be easily imagined by a person skilled in the art, those that are substantially the same, and those that are within the so-called equivalent range. Furthermore, the constituent elements disclosed in the embodiments and examples described below may be appropriately combined or appropriately selected for use.

[0022] As shown in the schematic configuration of Figure 1, an embodiment of the present invention comprises a power system 10, for example a carport-type solar power generation facility 20, and a quick charger (hereinafter simply referred to as quick charger) 40 with built-in storage battery for an electric vehicle (EV) 50. Under normal circumstances, the quick charger charges the EV 50, supplies normal power to the building's normal loads 60, and supplies emergency power to an emergency load 62 which is an important power source. However, during a power outage in the power system (simply referred to as a power outage), the quick charger supplies emergency power only to the emergency load 62 which includes important power loads that use three-phase AC, such as a mechanical parking lot drive motor, a water supply lift pump, and appliances essential for daily life.

[0023] A detailed configuration of the embodiment is shown in FIG.

[0024] The carport-type solar power generation facility 20 includes solar panels (PV) 22, a standard solar power conditioner (PCS) 24 with alternating current (AC) output, and a solar PCS 26 with direct current (DC) output.

[0025] In the figure, 30A and 30B are battery control units that control the charging and discharging of two large-capacity storage batteries 44A and 44B, each of which has a capacity of approximately 26 kWh, built into the rapid charger 40; 32 is a three-phase output independent inverter; 34 is a DC main line that connects the solar PCS 26, battery control units 30A and 30B, and the independent inverter 32; 36 is an overall controller that controls these and, in accordance with commands from a user interface 38, switches the connections of the solar panels 22 and the solar PCSs 24 and 26, the switching device 70 that switches the connection of the built-in storage batteries 44A and 44B, and the switching device 74 that switches the connection from the power grid 10 and the independent inverter 32 to an emergency load 62, all of which are disposed in various locations; and 42 is an EV charging controller that is provided inside the rapid charger 40 and controls the charging of the EV 50.

[0026] In the above configuration, the stand-alone inverter 32 that drives the emergency load has a three-phase output, but since the emergency load may require single-phase power, such as an air conditioner or lighting device, the stand-alone inverter is not limited to a three-phase output, and a single-phase output inverter can also be used. Also, a stand-alone inverter that can be switched between a three-phase output and a single-phase output can be used.

[0027] 2, the AC output from the power system 10 and the standard solar PCS 24 is used via the EV charge controller 42 of the quick charger 40 to charge a large-capacity built-in storage battery (referred to as system A) 44A and a built-in storage battery (referred to as system B) 44B, each with a capacity of, for example, 26 kWh, and to charge the EV 50. The AC output from the power system 10 and the solar PCS 24 is also supplied to a normal load 60 and an emergency load 62 of a building or the like.

[0028] On the other hand, during a power outage, AC power is no longer supplied from power grid 10, and so as shown by the solid line in Figure 3, built-in batteries 44A, 44B are charged from DC output solar PCS 26 by battery control unit 30A and battery control unit 30B provided for each built-in battery 44A, 44B of quick charger 40, and depending on the state of built-in batteries 44A, 44B, three-phase AC power is supplied only to emergency load 62 via DC main line 34 and three-phase output independent inverter 32, as will be explained in detail later.

[0029] The battery control units 30A, 30B and the stand-alone inverter 32 are controlled by an overall controller 36, and can be easily switched using switching devices 70, 72, 74 in response to inputs from a user interface 38.

[0030] Figure 4 shows the operating sequence depending on the remaining capacity of each of the two internal storage batteries 44A, 44B and the state of the photovoltaic power generation PV during normal operation when three-phase AC is supplied from the power grid 10 and power supply to only the emergency load 62 is not required.

[0031] In the figure, a circle indicates, for example, a battery remaining charge of 70% or more, a triangle indicates, for example, a battery remaining charge of 30-70%, and an x ​​indicates, for example, a battery remaining charge of 30% or less. In particular, the remaining charge setting, which determines the x mark, can be changed according to the requirements of the device connected to the load. For example, when driving an elevator as an emergency load 62, it is necessary to avoid the elevator stopping midway due to insufficient charge.

[0032] In Figure 4, when power supply to only the emergency load 62 is not required during normal times, if the remaining capacity of both the A-system storage battery 44A and the B-system storage battery 44B is marked with a circle, no charging operation is performed and power is supplied to the normal load 60 from the solar power generation PV according to the state of sunlight.

[0033] On the other hand, when the remaining capacity of the B-system storage battery 44B is insufficient, the B-system storage battery 44B is charged by the photovoltaic power generation PV and / or the power from the power system 10 (referred to as system power).

[0034] Furthermore, when the remaining charge of the A-system storage battery 44A is insufficient, the A-system storage battery 44A is charged by photovoltaic power generation PV and / or grid power.

[0035] Furthermore, when the remaining power of both the A-system battery 44A and the B-system battery 44B is insufficient, both the A-system and B-system batteries 44A and 44B are charged by photovoltaic power generation PV and / or grid power.

[0036] On the other hand, FIG. 5 shows an operation sequence depending on the state of the two sets of built-in storage batteries 44A, 44B and the photovoltaic power generation PV during a power outage when power supply to only the emergency load 62 is required.

[0037] In this case, if both the A-system storage battery 44A and the B-system storage battery 44B have sufficient remaining capacity, both the A-system storage battery 44A and the B-system storage battery 44B discharge only to the emergency load 62. Photovoltaic power generation PV also assists according to the state of sunlight.

[0038] Furthermore, if the remaining charge of the B-system storage battery 44B is insufficient, the A-system storage battery 44A discharges only to the emergency load 62, and also assists the photovoltaic power generation PV. If there is surplus power, the B-system storage battery 44B is charged by the photovoltaic power generation PV.

[0039] Furthermore, if the remaining charge of the A-system battery 44A is insufficient, the B-system battery 44B discharges only to the emergency load 62, and also assists the photovoltaic power generation PV. If there is surplus power, the A-system battery 44A is charged by the photovoltaic power generation PV.

[0040] Furthermore, if the remaining charge of both the A-system storage battery 44A and the B-system storage battery 44B is insufficient, power cannot be supplied to the emergency load 62, so the storage batteries 44A and / or 44B are charged by the photovoltaic power generation PV. If charging by the photovoltaic power generation PV progresses and the required charge amount is secured, it becomes possible to supply power only to the emergency load 62. In this case, a message to that effect is displayed to the user.

[0041] Furthermore, as mentioned above, the remaining battery charge at which both the A and B system batteries are unable to supply power to the emergency load due to insufficient charge varies depending on the capacity and nature of the load being used, and is not a fixed value. For example, if the emergency load is an elevator, it needs to have sufficient remaining charge to prevent it from stopping midway through the elevator due to battery exhaustion. On the other hand, if the emergency load is one that is allowed to stop midway, it is desirable to set the remaining charge limit as low as possible and extend the time that power can be supplied to the emergency load.

[0042] In this way, by making it possible to change the setting of the remaining battery capacity through the user interface 38 in accordance with the capacity and characteristics of the load, it becomes possible to set an appropriate remaining capacity in accordance with the installation location.

[0043] Although it is not possible to simultaneously charge and discharge a storage battery, by providing multiple storage batteries (two sets in this embodiment) as described above, it is possible to simultaneously charge and discharge the storage battery according to the remaining capacity of each battery. Note that, although the number of storage batteries is two in the above embodiment, the number of storage batteries is not limited to two, and may be three or more.

[0044] In the above embodiment, the solar power generation facility 20 is a carport type, and the solar panel 22 is provided on the roof of the carport, so space can be saved by installing the quick charger 40 inside the carport while protecting the EV 50. Note that the solar power generation facility 20 is not limited to a carport type, and the solar panel 22 may be provided separately from the carport.

[0045] Furthermore, in the above embodiment, the rapid charger 40 for the EV 50 is used as the charger, and therefore the rapid charger 40 for the EV 50 equipped with the large-capacity storage batteries 44A, 44B can be effectively utilized. Note that the type of charger is not limited to a rapid charger for the EV 50, and the object to be charged by the charger is not limited to the EV 50. [Explanation of symbols]

[0046] 10…Power system 20...(Carport type) Solar power generation equipment 22...Solar panels (PV) 24, 26...Solar power conditioner (PCS) 30A, 30B...Battery control unit 32...Standalone inverter 34...DC trunk line 36...Overall Controller 38...User Interface 40... Rapid charger with built-in battery 42...EV charge controller 44A, 44B...Built-in battery 50...Electric vehicle (EV) 60…Normal load 62…Emergency load 70, 72, 74...Switching device

Claims

1. A charger with multiple built-in batteries, a charge / discharge control means provided for each storage battery; Solar power generation facilities and a means for switching a combination of a charging state of each storage battery, a discharging state of each storage battery, and a power supply state to a load according to a state of the power grid, a state of sunlight, and a remaining charge of each storage battery; An emergency power supply system that combines a built-in battery charger and a solar power generation facility.

2. 2. The emergency power supply system combining a battery-integrated charger and a solar power generation facility according to claim 1, characterized in that, in the event of a power outage in which power cannot be received from the power grid, if at least one of the storage batteries has sufficient remaining battery power depending on the remaining battery power and the state of sunlight, that storage battery is discharged to the emergency load and power is supplied from the solar power generation facility, and if all of the storage batteries have insufficient remaining battery power, discharging from the storage batteries to the emergency load is stopped until charging of the storage batteries by the solar power generation facility progresses.

3. 2. An emergency power supply system combining a battery-equipped charger and a solar power generation facility according to claim 1, wherein the emergency load includes a power load that must operate even during a power outage.

4. 2. An emergency power supply system combining a battery-equipped charger and a solar power generation facility according to claim 1, wherein the charger is a rapid charger for an electric vehicle equipped with a large-capacity storage battery.

5. 2. An emergency power supply system combining a battery-equipped charger and a solar power generation facility according to claim 1, wherein the solar power generation facility and the charger are both installed in a parking lot.

6. An emergency power supply system combining a battery-equipped charger and a solar power generation facility as described in claim 5, characterized in that the solar power generation facility comprises solar panels arranged on the roof of a parking lot, and the charger is arranged in the same parking lot.

7. 2. An emergency power supply system that combines a battery-integrated charger and a solar power generation facility according to claim 1, characterized in that, during normal times when power can be received from the power grid, at least one of the storage batteries is charged depending on the state of sunlight.

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