Power generation control system and power generation control method

Abstract

To effectively use residual power in the case of employing photovoltaic generation and a storage battery in order to adjust power demand-supply balance with charging and discharging control of the storage battery.SOLUTION: A power generation control system comprises: a management unit 11a that regularly acquires and manages solar radiation quantity data, actual power generation data, total output power data, power consumption data and the like; a computation unit 11b that calculates an estimated power generation on the basis of the solar radiation quantity data and calculates a control ratio for a power conditioner on the basis of the total output power data and the actual power generation data; and a main control unit 11d that drives and controls the power conditioner so as to charge the storage battery with a difference amount between the estimated power generation and the actual power generation amount as residual power in the case where the estimated power generation exceeds the actual power generation amount, the control ratio is not 100%, and a difference between the estimated power generation and the actual power generation is equal to a predetermined threshold value or larger.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a technique for effectively utilizing surplus electricity when, for example, photovoltaic power generation and a storage battery are employed to adjust the balance between supply and demand of electricity by controlling the charging and discharging of the storage battery. [Background technology]

[0002] Conventionally, in power generation control using solar cells, solar cells installed in a facility convert sunlight into DC power and output it to a power conditioner. The power conditioner then converts the DC power into AC power, controls the power generated by the solar cells, and makes the AC power available for use by loads such as household electrical appliances.

[0003] For example, Patent Document 1 discloses a power system including a solar cell capable of supplying generated power to a load and capable of reverse power flow to a power grid, a storage battery capable of charging power supplied from the power grid and discharging the charged power to supply it to the load, and a controller for controlling the charging and discharging of the storage battery. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2017-11950 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, the conventional techniques disclosed in Patent Document 1 and the like do not disclose anything about the power conditioner charging a storage battery or the like with surplus power whose output has been controlled, thereby making effective use of the surplus power.

[0006] The present invention has been made in consideration of such problems, and has an object to provide a technique for making effective use of surplus electricity when solar power generation and storage batteries are adopted. [Means for solving the problem]

[0007] In order to solve the above problem, a power generation control system according to one aspect of the present invention includes a solar cell that outputs DC power, a measurement unit that measures the amount of solar radiation around the installation position of the solar cell, a power conditioner that converts the DC power to AC power and controls the generated power, a storage battery that accumulates surplus power from the generated power, a power receiving and transforming unit that distributes and supplies received power to a load, and periodically converts solar radiation amount data output from the measurement unit, actual power generation power data of the solar cell and total output power data of the power conditioner output from the power conditioner, power consumption amount data of the load from the power receiving and transforming unit, etc. a calculation unit that calculates an estimated power generation amount based on the solar radiation data managed by the management unit, and calculates a control rate of the power conditioner based on the total output power data and the actual power generation data; and a main control unit that drives and controls the power conditioner so that, when the estimated power generation amount exceeds the actual power generation amount, the control rate is not 100%, and the difference between the estimated power generation amount and the actual power generation amount is equal to or greater than a predetermined threshold, the difference between the estimated power generation amount and the actual power generation amount is charged as surplus power to the storage battery.

[0008] Furthermore, a power generation control method according to another aspect of the present invention periodically acquires and manages solar radiation data output from a measurement unit, actual power generation data of a solar cell and total output power data of the power conditioner output from a power inverter, power consumption data of a load from a power receiving and transforming unit, etc., calculates an estimated power generation amount based on the solar radiation data, calculates a control rate of the power conditioner based on the total output power data and the actual power generation data, and controls the power conditioner to drive so that, when the estimated power generation amount exceeds the actual power generation amount, the control rate is not 100%, and the difference between the estimated power generation amount and the actual power generation amount is equal to or greater than a predetermined threshold, the difference between the estimated power generation amount and the actual power generation amount is charged as surplus power to the storage battery. Effect of the Invention

[0009] According to the present invention, when solar power generation and a storage battery are employed, a technique for effectively utilizing surplus power can be provided. [Brief description of the drawings]

[0010] [Figure 1] 1 is a configuration diagram of a power generation control system according to an embodiment of the present invention. [Diagram 2] 1 is a flowchart showing a processing procedure performed by the system. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0012] FIG. 1 shows the configuration of a power generation control system according to one embodiment of the present invention.

[0013] As shown in the figure, the power generation control system 1 is composed of a control unit 11 that controls the entire system, a memory unit 12, a power conditioner (PCS) 13, a power receiving and transforming unit 14, a measurement unit 15, a solar cell 16, a storage battery 17, a load 18, an inverter 19, and an EV (Electric Vehicle) charger 20. Here, the load 18 refers to a general electric device that consumes power, such as a home appliance. The measurement unit 15 is composed of a sensor unit that measures the amount of solar radiation, etc. Although not shown in the figure, the load 18 and the EV charger 20 are also electrically connected to the power conditioner 13 and the inverter 19, and the power conditioner 13 is also electrically connected to the storage battery 17, the power receiving and transforming unit 14, and the inverter 19.

[0014] A solar cell 16 installed in a facility or the like converts sunlight into DC power and outputs it to a power conditioner 13 as generated power. The power conditioner 13 controls the power generated by the solar cell 16. That is, the power conditioner 13 converts the DC power of the solar cell 16 into AC power and makes the AC power available to a load 18 such as a household electrical appliance. Surplus power from the solar cell 16 is stored in a storage battery 17 via the power conditioner 13 and an inverter 19. The surplus power from the storage battery 17 can be supplied to an EV charger 20, and can also be supplied to the load 18 via the power conditioner 13 and the power receiving and transforming unit 14.

[0015] The power conditioner 13 is connected to the power receiving and transforming unit 14 via a power line, and the power receiving and transforming unit 14 is connected to a load 18, so that the generated power is output from the power conditioner 13 to the load 18 via the power receiving and transforming unit 14 and consumed by the load 18. Although not shown, the power receiving and transforming unit 14 may be connected to a plurality of power sources via power lines, in which case it is also possible to distribute and supply the received power to the load 18.

[0016] The control unit 11 includes a management unit 11a, a calculation unit 11b, a reverse power flow prevention unit 11c, and a main control unit 11d.

[0017] The management unit 11a manages the solar radiation data output from the measurement unit 15, the actual power generation data of the solar cell 16 and the total output power data of the power conditioner output from the power conditioner 13, the power consumption data of the load 18 from the power receiving and transforming unit 14, etc. by periodically acquiring these data and storing them in the memory unit 12.

[0018] The calculation unit 11b periodically (for example, at intervals of 1 to 5 minutes) calculates an estimated amount of generated power by calculation based on, for example, JIS8907C based on the solar radiation data managed by the management unit 11a, and calculates a control rate of the power conditioner 13 based on the total output power data of the power conditioner 13 and the actual power generation data of the solar cell 16 managed by the management unit 11a. The control rate is calculated, for example, by dividing the actual power generation amount by the total output power amount.

[0019] The main control unit 11d first determines whether the estimated power generation amount exceeds the actual power generation amount, and if the estimated power generation amount exceeds the actual power generation amount, then determines whether the control rate of the power conditioner 13 is not 100%, and if it is not 100%, then determines whether the difference between the estimated power generation amount and the actual power generation amount is equal to or greater than a predetermined threshold value that has been set in advance, and if it is not equal to or greater than the threshold value, issues a command to the power conditioner 13 to charge the storage battery 17 with the difference between the estimated power generation amount and the actual power generation amount as surplus power. Upon receiving this command from the main control unit 11d, the power conditioner 13 charges the storage battery 17 with the surplus power via the inverter 19.

[0020] On the other hand, the main control unit 11d does not perform charging if the estimated power generation amount does not exceed the actual power generation amount, if the control rate of the power conditioner 13 is 100%, or if the difference between the estimated power generation amount and the actual power generation amount is less than a predetermined threshold value.

[0021] For example, if the total output power of the power conditioner 13 is 160 kW, the estimated power generation power is 120 kW, the actual power generation power is 100 kW, the control rate is 62.5%, and the threshold is 5 kW, 20 kW of power, which is the difference between the estimated power generation power and the actual power generation power, is charged to the storage battery 17.

[0022] Then, when the total output power of the power conditioner 13 is 160 kW, the estimated power generation power is 150 kW, the actual power generation power is 10 kW, the control rate is 6.3%, and the threshold is 5 kW, 140 kW of power, which is the difference between the estimated power generation power and the actual power generation power, is charged to the storage battery 17.

[0023] Furthermore, when the total output power of the power conditioner 13 is 160 kW, the expected power generation power is 100 kW, the actual power generation power is 90 kW, the control rate is 100%, and the threshold is 5 kW, although there is surplus power, no charging takes place because the control rate is 100%.

[0024] Furthermore, when the total output power of the power conditioner 13 is 160 kW, the expected power generation power is 10 kW, the actual power generation power is 7 kW, the control rate is 40%, and the threshold is 5 kW, although the control rate is not 100%, the difference between the expected power generation power and the actual power generation power is below the threshold, so although there is surplus power, it is not charged to the storage battery 17.

[0025] In addition, when the actual generated power amount managed by the management unit 11a exceeds the consumed power amount, the reverse power flow prevention unit 11c prevents reverse power flow of the power conditioner 13. The main control unit 11d is responsible for driving control of the power conditioner 13, and also controls the accumulation of surplus power in the storage battery, the supply of power to the EV charger 20, the supply of power to the load 18, etc.

[0026] The process steps performed by the power generation control system according to the embodiment of the present invention will be described in detail below with reference to the flowchart in Fig. 2. The process steps also correspond to the power generation control method according to the embodiment of the present invention.

[0027] The management unit 11a periodically acquires solar radiation data output from the measurement unit 15, actual power generation data of the solar cells 16 and total output power data of the power conditioner output from the power conditioner 13, power consumption data of the load 18 from the power receiving and transforming unit 14, etc., and stores them in the memory unit 12 to manage them (S1).

[0028] Next, the calculation unit 11b periodically (for example, at intervals of 1 to 5 minutes) calculates an estimated amount of power generation by calculation based on, for example, JIS8907C based on the solar radiation data managed by the management unit 11a, and calculates a control rate of the power conditioner 13 based on the total output power data of the power conditioner 13 and the actual power generation data of the solar cell 16 managed by the management unit 11a. The control rate is calculated, for example, by dividing the actual power generation amount by the total output power amount (S2).

[0029] Then, the main control unit 11d first judges whether the estimated power generation amount exceeds the actual power generation amount (S3). If the estimated power generation amount exceeds the actual power generation amount (branching S3 to Yes), the main control unit 11d then judges whether the control ratio of the power conditioner 13 is not 100% (S4). If it is not 100% (branching S4 to Yes), then it judges whether the difference between the estimated power generation amount and the actual power generation amount is equal to or greater than a predetermined threshold value (S5). If it is not equal to or greater than the threshold value (branching S5 to Yes), it issues a command to the power conditioner 13 to charge the storage battery 17 with the difference between the estimated power generation amount and the actual power generation amount as surplus power. In response to this command from the main control unit 11d, the power conditioner 13 charges the surplus power to the storage battery 17 via the inverter 19 (S6).

[0030] On the other hand, the main control unit 11d does not perform charging (S7) if the estimated power generation amount does not exceed the actual power generation amount (branching S3 to No), if the control rate of the power conditioner 13 is 100% (branching S4 to No), or if the difference between the estimated power generation amount and the actual power generation amount is less than a predetermined threshold value (branching S5 to No). In this way, the series of processes is completed.

[0031] As described above, according to one embodiment of the present invention, the following effects are achieved.

[0032] That is, the system includes a solar cell 16 that outputs DC power, a measurement unit 15 that measures the amount of solar radiation around the solar cell installation position, a power conditioner 13 that converts DC power to AC power and controls the generated power, a storage battery 17 that accumulates surplus power of the power conditioner, a power receiving and transforming unit 14 that distributes and supplies the received power to the load, and a management unit 11a that periodically acquires and manages the solar radiation amount data output from the measurement unit, the actual generated power data of the solar cell and the total output power data of the power conditioner output from the power conditioner, the power consumption amount data of the load from the power receiving and transforming unit, and the like. Based on the solar radiation amount data managed by the management unit, the management unit calculates an expected amount of generated power and compares the total output power data and the actual power output data. The power generation control system includes a calculation unit 11b that calculates a control rate of the power conditioner (for example, actual power generation amount / total output power amount) based on the generated power data, and a power conditioner control unit 11d that determines whether the estimated power generation amount exceeds the actual power generation amount, and if the estimated power generation amount exceeds the actual power generation amount, then determines whether the control rate is not 100%, and if it is not 100%, then determines whether the difference between the estimated power generation amount and the actual power generation amount is equal to or greater than a predetermined threshold value that has been set in advance, and if it is equal to or greater than the threshold value, then controls the drive of the power conditioner so that the difference between the estimated power generation amount and the actual power generation amount is charged as surplus power to the storage battery. Therefore, it is possible to efficiently charge the surplus power to the storage battery and make effective use of it. Furthermore, by supplying the surplus power stored in the storage battery to an EV charger, it is possible to realize self-sufficiency in power, for example, in an ordinary household.

[0033] Furthermore, a power generation control method is provided in which the solar radiation amount data output from the measurement unit 15, the actual power generation amount data of the solar cell output from the power conditioner, the total output power data of the power conditioner, the power consumption amount data of the load from the power receiving and transforming unit, etc. are periodically acquired and managed, the estimated power generation amount is calculated based on the solar radiation amount data, the control rate of the power conditioner 13 (for example, actual power generation amount / total output power amount) is calculated based on the total output power data and the actual power generation amount data, whether the estimated power generation amount exceeds the actual power generation amount is determined, and if the estimated power generation amount exceeds the actual power generation amount, whether the control rate is not 100% or not is determined, and if it is not 100%, whether the difference between the estimated power generation amount and the actual power generation amount is equal to or greater than a predetermined threshold value, and if it is equal to or greater than the threshold value, the difference between the estimated power generation amount and the actual power generation amount is charged as surplus power to the storage battery. Therefore, it is possible to efficiently charge the surplus power to the storage battery and make effective use of it. Furthermore, by supplying the surplus power stored in the storage battery to an EV charger, it will be possible to achieve self-sufficiency in electricity for, for example, an average household.

[0034] Although one embodiment of the present invention has been described above, the present invention is not limited to this embodiment, and various improvements and modifications can be made without departing from the spirit and scope of the present invention.

[0035] For example, the power receiving unit may be connected to a commercial power line of a power company or the like. [Explanation of symbols]

[0036] 1...power generation control system, 11...control unit, 11a...management unit, 11b...calculation unit, 11c...reverse power flow prevention unit, 11d...main control unit, 12...memory unit, 13...power conditioner, 14...power receiving and transforming unit, 15...measurement unit, 16...solar cell, 17...storage battery, 18...load, 19...inverter for storage battery / EV charger, 20...EV charger.

Claims

1. A solar cell that outputs DC power; A measurement unit that measures the amount of solar radiation around the solar cell installation position; A power conditioner that converts the DC power into AC power and controls the generated power; a storage battery that stores surplus power from the generated power; A power receiving and transforming unit that distributes and supplies received power to a load; A management unit that periodically acquires and manages the solar radiation data output from the measurement unit, the actual power generation data of the solar cell and the total output power data of the power conditioner output from the power conditioner, and the power consumption data of the load from the power receiving and transforming unit, etc.; A calculation unit that calculates an estimated power generation amount based on the solar radiation data managed by the management unit, and calculates a control rate of the power conditioner based on the total output power data and the actual power generation data; a main control unit that drives and controls the power conditioner so that, when the estimated amount of power generation exceeds the actual amount of power generation, the control rate is not 100%, and the difference between the estimated amount of power generation and the actual amount of power generation is equal to or greater than a predetermined threshold, the power conditioner charges the storage battery with a difference between the estimated amount of power generation and the actual amount of power generation as surplus power; A power generation control system equipped with:

2. The solar radiation data output from the measurement unit, the actual power generation data of the solar cells output from the power conditioner, the total output power data of the power conditioner, and the power consumption data of the load output from the power receiving and transforming unit are periodically acquired and managed. Calculating an estimated amount of generated power based on the solar radiation data, and calculating a control rate of the power conditioner based on the total output power data and the actual generated power data; When the estimated power generation amount exceeds the actual power generation amount, the control rate is not 100%, and the difference between the estimated power generation amount and the actual power generation amount is equal to or greater than a predetermined threshold, the power conditioner is driven and controlled so that the difference between the estimated power generation amount and the actual power generation amount is charged to the storage battery as surplus power. Power generation control method.

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