Power supply device for renewable energy power generation

Abstract

Provided is a system for efficiently storing power and supplying power even when generated power from a renewable energy source including photovoltaic power generation is not stable. The system is characterized by comprising: a capacitor battery 13 that is formed using a large-capacity capacitor to which electric energy is charged and stores the generated power; a power distribution control unit 11 that performs distribution control in which the generated power from the renewable energy source is distributed as sold power to be transmitted to a power company or as a storage power to be stored in the capacitor battery 13; and a capacitor control unit 12 that performs control for storing the storage power distributed from the power distribution control unit 11 in the capacitor battery 13, performs control for discharging the power stored in the capacitor battery 13 to store the power in a secondary battery 20, and performs control for discharging the power stored in the capacitor battery 13 to supply power to an external device.

Description

Renewable energy power generation power supply equipment

[0001] The present invention relates to a renewable energy power generation power supply device that efficiently stores and supplies power generated from renewable energy sources, including solar power generation.

[0002] Unlike fossil energy, which is a finite resource such as oil, coal, and natural gas, renewable energy is energy that is always present in nature, such as solar, wind, and geothermal power, and is easily affected by the natural environment. As this energy is easily affected by the natural environment, technological development of power generation systems using renewable energy is progressing every day. In particular, as solar power generation systems become more widespread, there is a demand for stable power supply that meets power supply and demand.

[0003] For example, Patent Document 1 discloses a power supply system that includes multiple power supply systems each including a DC / DC converter that converts DC power output from a solar panel and a storage battery, and a DC / AC inverter that converts the output of the DC / DC converter into AC power, and that collects and outputs the AC power output from the multiple power supply systems, thereby making it possible to supply stable power according to the power demand of the load system.

[0004] Japanese Patent Application Laid-Open No. 2023-073396

[0005] However, because the amount of electricity generated by solar power generation is unstable and only a small amount can be generated at certain times of the day, there are cases where the electricity cannot be used to sell to power companies and ends up being wasted. This has created a need for more efficient energy storage and supply technology.

[0006] In view of the above circumstances, an object of the present invention is to provide a system that efficiently stores and supplies electricity even when the electricity generated from renewable energy sources, including solar power generation, is unstable.

[0007] A renewable energy power generation power supply device of a first invention is a device that efficiently stores and supplies power generated from a renewable energy source including solar power generation, and comprises: a capacitor battery formed using a capacitor that charges a large amount of electrical energy and that stores the power generated from the renewable energy source; a power distribution control unit that controls the distribution of the power generated from the renewable energy source into power to be sold to an electric power company or power to be stored in the capacitor battery; and a capacitor control unit that controls the storage of the stored power distributed by the power distribution control unit in the capacitor battery, and also controls the discharging of the power stored in the capacitor battery to store it in a secondary battery, and the discharging of the power stored in the capacitor battery to supply power to an external device, wherein the power distribution control unit The system is characterized in that it has a means for performing allocation control such that, when the input voltage value of the generated power is less than a predetermined first reference value, all of the generated power is allocated as storage power to be stored in the capacitor battery, and, when the input voltage value of the generated power is equal to or greater than the first reference value, a predetermined fixed amount of power is allocated from the generated power as the power to be sold, and the remaining surplus power is allocated as storage power to be stored in the capacitor battery.

[0008] The second aspect of the present invention is a power supply device for renewable energy power generation according to the first aspect, characterized in that the capacitor control unit has: means for monitoring the remaining charge of the capacitor battery in real time, and, when the remaining charge is equal to or less than a predetermined second reference value, for cutting off control of discharging the power stored in the capacitor battery and storing it in a secondary battery; and means for controlling, when the voltage value of the power stored in the capacitor battery is less than a predetermined third reference value, for boosting the voltage value using a boost converter and storing it in the secondary battery.

[0009] The third aspect of the present invention is a power supply device for renewable energy power generation, which is the same as the first aspect, and is characterized in that the capacitor control unit has: means for monitoring the remaining charge of the capacitor battery in real time, and, when the remaining charge is equal to or less than a predetermined second reference value, for cutting off control of discharging the power stored in the capacitor battery and supplying power to an external device; and means for controlling, when the voltage value of the power stored in the capacitor battery is less than a predetermined fourth reference value, for boosting the voltage value using a boost converter and supplying power to the external device.

[0010] A fourth aspect of the present invention is a power supply device for renewable energy power generation, which is the same as the first aspect, characterized in that the capacitor control unit controls the discharging of the power stored in the secondary battery to supply power to an external device, and has means for controlling the boost converter to boost the voltage value and supply power to the external device when the voltage value of the power stored in the secondary battery is less than a fourth reference value set in advance.

[0011] According to the present invention, it is expected that it will be possible to efficiently store and supply electricity even when the electricity generated from renewable energy sources, including solar power generation, is unstable. Furthermore, since the amount of electricity generated from renewable energy sources, including solar power generation, is only weak depending on the time of day, electricity that has conventionally been wasted and cannot be used to sell to electric power companies can be stored in a capacitor battery, which is expected to result in efficient electricity storage.

[0012] Here, a capacitor battery is formed, for example, using a capacitor that charges a large amount of electrical energy, and is capable of charging a large amount of electrical energy (several kWh to several hundred MWh), and has the advantages of being capable of rapid charging and discharging and having a long lifespan.

[0013] Fig. 1 is a functional configuration diagram showing an example of the functional configuration of a renewable energy power generation power supply device according to an embodiment of the present invention. Fig. 2 is a schematic diagram showing the relationship between power generated from a renewable energy source, power sold, and stored power in a renewable energy power generation power supply device according to an embodiment of the present invention. Fig. 3 is a system configuration diagram showing an example of a renewable energy power generation power supply system configured using a renewable energy power generation power supply device according to an embodiment of the present invention. Fig. 4 is a schematic diagram showing an example of a case in which a secondary battery is charged from a rapid charger using a renewable energy power generation power supply device according to an embodiment of the present invention.

[0014] A renewable energy power generation power supply device according to one embodiment of the present invention will be described with reference to FIG.

[0015] 1 is a functional configuration diagram showing an example of the functional configuration of a renewable energy power generation power supply device according to an embodiment of the present invention. As shown in Fig. 1, the renewable energy power generation power supply device 10 includes a power distribution control unit 11, a capacitor control unit 12, a capacitor battery 13, a DC / DC converter 14, and a DC / AC inverter 15, and controls the efficient storage of power generated from a renewable energy source, including solar power generation, in a capacitor battery 20, the storage of power from the capacitor battery 13 in a secondary battery 20, and the supply of power from the capacitor battery 13 to external devices.

[0016] The power distribution control unit 11 controls the distribution of power generated from renewable energy sources including solar power generation into power to be sold to an electric power company or power to be stored in the capacitor battery 13 .

[0017] Here, when the input voltage value of the generated power is less than a predetermined first reference value, the power distribution control unit 11 controls the allocation of all of the generated power as storage power to be stored in the capacitor battery 13, and when the input voltage value of the generated power is equal to or greater than the first reference value, the power distribution control unit 11 controls the allocation of a predetermined fixed amount of power from the generated power as the power to be sold, and the remaining surplus power as storage power to be stored in the capacitor battery 13.

[0018] The first reference value is set in advance for various external environments, and is configured so that the setting can be changed as appropriate in response to changes in the external environment.

[0019] Figure 2 is a schematic diagram showing the relationship between the power generated from renewable energy sources, the power sold, and the stored power. As shown in Figure 2, when the generated power is equal to or greater than the first reference value, i.e., during the power selling time period to the power company (3.7 hours nationwide on average), the power is sent to the power company for sale. When the generated power is less than the first reference value, i.e., during the time period outside the power selling time period to the power company, the generated power is too small to be used for selling to the power company. This power would have been discarded in the past, but it is now stored in the capacitor battery 13 using the renewable energy power generation power supply device 10 of the present invention.

[0020] For example, solar panels generate electricity from sunrise to sunset because they can generate power even with a weak amount of light, but depending on the time of day only a weak amount of power can be generated. Conventionally, this power could not be used to sell electricity to the power company and was discarded, but the renewable energy power generation power supply device 10 of the present invention can be used to store the power in the capacitor battery 13.

[0021] Therefore, the renewable energy power generation power supply device 10 makes it possible to efficiently store electricity in the capacitor battery 13 even when the amount of electricity generated from the renewable energy source is unstable or when only a weak amount of electricity is generated during certain times of the day.

[0022] Next, we will explain the capacitor control unit 12. The capacitor control unit 12 controls the storage of the stored power allocated by the power distribution control unit 11 in the capacitor battery 13, controls the discharging of the power stored in the capacitor battery 13 to store it in the secondary battery 20, and controls the discharging of the power stored in the capacitor battery 13 to supply it to an external device.

[0023] Here, the capacitor control unit 12 performs control to efficiently store the stored power in the capacitor battery 13 even when the stored power allocated from the power distribution control unit 11 only generates a weak amount of power.

[0024] Furthermore, the capacitor control unit 12 monitors the remaining amount of electricity stored in the capacitor battery 13 in real time, and when the remaining amount of electricity stored is equal to or less than a preset second reference value, performs the following controls: - Cuts off the control of discharging the power stored in the capacitor battery 13 and storing it in the secondary battery 20. - Cuts off the control of discharging the power stored in the capacitor battery 13 and supplying it to an external device.

[0025] The second reference value is set in advance according to the capacity of the capacitor battery 13, and is configured so that the setting can be changed as appropriate according to changes in the external environment.

[0026] Furthermore, when the voltage value of the power stored in the capacitor battery 13 is less than a preset third reference value, the capacitor control unit 12 controls the boost converter to boost the voltage value and store the power in the secondary battery 20. When the voltage value of the power stored in the capacitor battery 13 is equal to or greater than the third reference value, the capacitor control unit 12 controls the secondary battery 20 to store the power without boosting the voltage value. The third reference value is set in advance according to the characteristics of the secondary battery 20, and is configured to be changeable as needed according to changes in the external environment.

[0027] In the example shown in FIG. 1, the DC / DC converter 13 is used as a converter for boosting the voltage value of the stored power, but the present invention is not limited to this, and a power conditioner, for example, may also be used.

[0028] The capacitor battery 13 is formed using a capacitor that charges a large amount of electrical energy, and is capable of charging a large amount of electrical energy (several kWh to several hundred MWh), and has the advantages of being capable of high-speed charging and discharging and having a long life.

[0029] Furthermore, the secondary battery 20 may be configured, for example, to include a plurality of secondary batteries. In this case, the plurality of secondary batteries may each have a different storage capacity. The capacitor control unit 12 may be configured to monitor the remaining charge levels of the plurality of secondary batteries in real time and to control the plurality of secondary batteries to optimally store power based on, for example, preset priorities and rules. The priorities and rules may also be configured to be changeable as needed.

[0030] The capacitor control unit 12 also controls the discharging of the power stored in the capacitor battery 13 to supply the power to the external device. In this case, when the voltage value of the power stored in the capacitor battery 13 is less than a preset fourth reference value, the capacitor control unit 12 controls the boost converter to boost the voltage value and supply the power to the external device. When the voltage value of the power stored in the capacitor battery 13 is equal to or greater than the fourth reference value, the capacitor control unit 12 controls the power to be supplied to the external device without boosting the voltage value.

[0031] The fourth reference value is set in advance depending on the condition of the external device to be powered, and is configured so that the setting can be changed as appropriate depending on changes in the external environment.

[0032] Furthermore, the capacitor control unit 12 controls the discharging of the power stored in the secondary battery 20 to supply the power to the external device. In this case, when the voltage value of the power stored in the secondary battery 20 is less than a preset fourth reference value, the capacitor control unit 12 controls the boost converter to boost the voltage value and supply the power to the external device. On the other hand, when the voltage value of the power stored in the secondary battery 20 is equal to or greater than the fourth reference value, the capacitor control unit 12 controls the power to be supplied to the external device without boosting the voltage value.

[0033] In the example shown in FIG. 1, when power is supplied to an external device, an AC / DC inverter 14 is used to convert DC voltage from the capacitor battery 13 or the secondary battery 20 into AC voltage, but this is not limited to this, and for example, a power conditioner, a DC / DC converter, etc. may also be used.

[0034] As examples of power supply to external devices, the secondary battery 20 can be used as an EV power supply station to supply power to a commercial power system, as a power supply for evacuation shelters or hospitals during emergencies, etc. Furthermore, it can also be transported to a destination and used as a power supply for evacuation shelters, for example.

[0035] Next, Fig. 3 is a system configuration diagram showing a renewable energy power generation power supply system configured using the renewable energy power generation power supply device 10 of the present invention. As shown in Fig. 3, the renewable energy power generation power supply system 30 has the renewable energy power generation power supply device 10 of the present invention and two billing systems 31 and 32.

[0036] The billing system 31 is configured to charge for the amount of electricity generated from a renewable energy source when purchasing the electricity, making it possible to purchase even a small amount of electricity that would conventionally be considered waste electricity.

[0037] The billing system 32 is configured to charge for the amount of power supplied when the renewable energy power generation power supply device 10 supplies power to an external device.

[0038] Furthermore, this renewable energy power generation power supply system 30 can be transported on a mobile vehicle such as a car or truck, and the system can be used by moving it from a location where there is surplus electricity to a location where electricity is needed (a location where no electricity transmission infrastructure is installed, a location where the electricity transmission infrastructure is damaged and cannot be used, etc.).

[0039] From the above, it is expected that the renewable energy power generation power supply system 30 will be used in cases where a business model is built in which power generated from renewable energy sources, including solar power generation, is efficiently stored and supplied.

[0040] In addition to the above-described embodiment, a case in which the renewable energy power generation power supply device 10 is used to charge the secondary battery 20 from a quick charger will be described with reference to FIG.

[0041] An example of the secondary battery 20 is a lithium-ion battery, and a case where a lithium-ion battery mounted on an electric vehicle (EV) is to be rapidly charged is envisioned. Generally, rapid charging of an EV is expected to be performed using EV stations located at gas stations, highway parking lots, etc. However, charging the lithium-ion battery mounted on an EV at a rate faster than its theoretical capacity shortens the battery life and may even result in damage. Therefore, by configuring the EV's lithium-ion battery (secondary battery) to be charged from a rapid charger via the renewable energy power generation power supply device 10, it becomes possible to safely charge the lithium-ion battery at ultra-high speeds without damaging it.

[0042] Although the embodiments for carrying out the present invention have been described above with reference to the drawings, the present invention is not limited to these embodiments.

[0043] DESCRIPTION OF SYMBOLS 10... Power supply device for renewable energy power generation 11... Power distribution control unit 12... Capacitor control unit 13... Capacitor battery 14... DC / DC converter 15... DC / AC inverter 20... Secondary battery 30... Power supply system for renewable energy power generation 31... Billing system 32... Billing system

Claims

1. A device for efficiently storing and supplying power generated from a renewable energy source including solar power generation, comprising: a capacitor battery formed using a capacitor that charges a large amount of electrical energy and that stores the power generated from the renewable energy source; a power distribution control unit that controls the allocation of the power generated from the renewable energy source to either power sold to an electric power company or power stored in the capacitor battery; and a capacitor control unit that controls the storage of the stored power allocated by the power distribution control unit in the capacitor battery, as well as controls the discharging of the power stored in the capacitor battery to store it in a secondary battery, and the discharging of the power stored in the capacitor battery to supply power to an external device, wherein the power distribution control unit: a means for performing allocation control such that, when the input voltage value of the generated power is less than a predetermined first reference value, all of the generated power is stored as power to be charged in the capacitor battery, and, when the input voltage value of the generated power is equal to or greater than the first reference value, a predetermined fixed amount of power is allocated from the generated power as power to be sold, and the remaining surplus power is stored as power to be charged in the capacitor battery.

2. A power supply device for renewable energy power generation according to claim 1, wherein the capacitor control unit has: means for monitoring the remaining charge of the capacitor battery in real time, and when the remaining charge is equal to or less than a preset second reference value, for cutting off control of discharging the power stored in the capacitor battery and storing it in the secondary battery; and means for controlling the boost converter to boost the voltage value and store it in the secondary battery when the voltage value of the power stored in the capacitor battery is less than a preset third reference value.

3. A power supply device for renewable energy power generation according to claim 1, wherein the capacitor control unit comprises: means for monitoring the remaining charge of the capacitor battery in real time, and when the remaining charge is equal to or less than a predetermined second reference value, for cutting off control of discharging the power stored in the capacitor battery and supplying power to an external device; and means for controlling the boost converter to boost the voltage value and supply power to the external device when the voltage value of the power stored in the capacitor battery is less than a predetermined fourth reference value.

4. A power supply device for renewable energy power generation according to claim 1, wherein the capacitor control unit controls the discharging of the power stored in the secondary battery to supply power to an external device, and when the voltage value of the power stored in the secondary battery is less than a fourth reference value set in advance, the power supply device for renewable energy power generation has means for controlling the boosting of the voltage value by a boost converter to supply power to the external device.

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