JP5413390B2 - Charge control device, charge control method, and photovoltaic power generation system - Google Patents

Description

  The present invention relates to a charge control device, a charge control method, and a solar power generation system, and more particularly to a charge control device, a charge control method, and a solar power generation system that can charge a storage battery more efficiently.

  In recent years, a photovoltaic power generation system including a photovoltaic power generation panel and a storage battery has become widespread. In such a photovoltaic power generation system, the electric power generated by the photovoltaic power generation panel is consumed by each load, and the storage battery is charged according to the amount of power generation and consumption.

  In addition, a plurality of charging methods have been proposed as charging methods for charging the storage battery with the electric power generated by the photovoltaic power generation panel. For example, the DC voltage power generated by the photovoltaic power generation panel is converted to AC voltage power by the power conditioner for the power generation panel, and is supplied to the bidirectional power conditioner via the distribution board. There is a charging method in which the storage battery is charged after being converted into electric power. In addition, the DC voltage power generated by the photovoltaic power generation panel is converted to the specified DC voltage power suitable for charging the storage battery by a DC / DC (Direct Current / Direct Current) converter, and then charged to the storage battery. There is a method.

  However, in these charging methods, the charging efficiency is lowered according to the conversion efficiency by the power conditioner or the DC / DC converter. Therefore, when using a charging method that charges the storage battery directly, that is, without performing voltage conversion by a power conditioner or a DC / DC converter, the power of the DC voltage generated by the photovoltaic power generation panel is used. It is assumed that a decrease in charging efficiency can be avoided.

  By the way, in the charging method that directly charges the storage battery with the electric power from the photovoltaic power generation panel, the voltage between the photovoltaic power generation panel and the storage battery is not adjusted, so the voltage fluctuation of the electric power output from the photovoltaic power generation panel is May affect the charging efficiency of the storage battery. For this reason, we are anxious about the charge efficiency of a storage battery falling depending on the irradiation condition of the sunlight to a photovoltaic power generation panel.

  Moreover, in order to charge a storage battery efficiently, performing charging control according to the condition of a storage battery is proposed, for example, patent document 1 performs charge control based on the temperature of a lithium ion secondary battery. Technology is disclosed.

JP 2009-148046 A

  As described above, there is a concern that the charging efficiency of the storage battery is reduced in the charging method in which the power from the photovoltaic power generation panel is directly charged to the storage battery. There is a need to charge storage batteries.

  This invention is made | formed in view of such a condition, and enables it to charge a storage battery more efficiently.

The charging control device according to one aspect of the present invention includes: an estimation unit that estimates whether or not a voltage value that maximizes power output from a power generation unit that generates power using natural energy increases; When it is estimated that the value rises, a charging start unit that starts charging the storage unit of the power generated by the power generation unit, and the power generation unit only when the power generated by the power generation unit is not charged to the power storage unit And a power converter that converts the power output from the power converter and outputs the power .

The power control method according to one aspect of the present invention estimates whether or not the voltage value that maximizes the power output from the power generation means that generates power using natural energy increases, and the voltage value is estimated to increase. The charging means starts charging the power generated by the power generation means, and converts and outputs the power output from the power generation means only when the power generated by the power generation means is not charged to the power storage means. Including steps.

The photovoltaic power generation system according to one aspect of the present invention includes a power generation unit that generates power using natural energy, a storage unit that charges power, and a voltage value that maximizes the power output from the power generation unit. An estimation means for estimating the charge value, a charging start means for starting charging of the storage means for storing the electric power generated by the solar power generation means when the estimation means estimates that the voltage value is increased, and the power generation means And a power converter that converts and outputs power output from the power generation means only when the stored power is not charged in the power storage means .

In one aspect of the present invention, when it is estimated that the voltage value that maximizes the power output from the power generation means that generates power using natural energy is increased, the power storage means stores the power generated by the power generation means. Is started, and the power output from the power generation means is converted and output only when the power generated by the power generation means is not charged in the power storage means.

  According to one aspect of the present invention, the storage battery can be charged more efficiently.

It is a block diagram which shows the structural example of one Embodiment of the solar energy power generation system to which this invention is applied. It is a figure which shows the current voltage characteristic and power voltage characteristic of a photovoltaic power generation panel. It is a figure which shows the charge characteristic in the system which charges with a constant current and a constant voltage. It is a figure explaining the example of charge when the amount of solar radiation tends to increase and fall. It is a flowchart explaining the process which judges the start of charge. It is a figure explaining the conditions of the simulation performed about the relationship between the amount of sunlight and charging efficiency. It is a figure which shows the result of having performed simulation. It is a figure which shows the charging efficiency calculated | required by simulation.

  Hereinafter, specific embodiments to which the present invention is applied will be described in detail with reference to the drawings.

  FIG. 1 is a block diagram showing a configuration example of an embodiment of a solar power generation system to which the present invention is applied. In the present specification, the term “system” represents the entire apparatus constituted by a plurality of apparatuses.

  In FIG. 1, the solar power generation system 11 includes a solar power generation panel 12, a storage battery 13, and a power control device 14.

  The solar power generation panel 12 is a panel configured by connecting a plurality of solar cell modules, and is a solar power generation means that generates power according to the amount of sunlight irradiated. The storage battery 13 is configured to include, for example, a lithium ion storage battery or a lead storage battery, and is storage means for storing (charging) power supplied via the power control device 14.

  The power control device 14 functions as a charge control device that controls charging of the power generated by the solar power generation panel 12 to the storage battery 13. In addition, the power control device 14 supplies the power generated by the photovoltaic power generation panel 12 to a load or a commercial power system (both not shown) via the distribution board, or commercializes via the distribution board. Power control is performed such that the power supplied from the power system is charged in the storage battery 13 or the power stored in the storage battery 13 is supplied to the load via the distribution board.

  The power control device 14 includes a diode 21, a switch 22, a bidirectional AC / DC (Alternating Current / Direct Current) conversion unit 23, a communication unit 24, and a control unit 25.

  In the power control device 14, the anode of the diode 21 is connected to the photovoltaic power generation panel 12. In addition, the cathode of the diode 21 is connected to the storage battery 13 via the switch 22 and also connected to the bidirectional AC / DC converter 23. The bidirectional AC / DC conversion unit 23 is connected to a commercial power system, each load, and the like via a distribution board, for example.

  The diode 21 allows the power from the photovoltaic power generation panel 12 to be supplied to the storage battery 13 and the bidirectional AC / DC converter 23, while the power from the storage battery 13 and the bidirectional AC / DC converter 23 is sunlight. The flow into the power generation panel 12 is restricted.

  The switch 22 is arranged in the wiring on the storage battery 13 side from the connection point between the diode 21 and the bidirectional AC / DC conversion unit 23. The switch 22 brings the connection between the photovoltaic power generation panel 12 and the bidirectional AC / DC converter 23 and the storage battery 13 into an open state or a closed state according to the control of the control unit 25.

  The bidirectional AC / DC converter 23 converts the DC voltage power output from the photovoltaic power generation panel 12 or the storage battery 13 into AC voltage power and outputs it to the distribution board, or is supplied via the distribution board. The AC voltage power is converted into DC voltage power and supplied to the storage battery 13. In addition, the bidirectional AC / DC converter 23 drives or stops power conversion in accordance with the control of the control unit 25.

  The communication unit 24 is connected to a network through a wired or wireless line, and acquires various types of information through communication via the network and supplies the information to the control unit 25.

  The control unit 25 controls the charging of the power generated by the solar power generation panel 12 to the storage battery 13 in accordance with the change in the amount of solar radiation applied to the solar power generation panel 12. Further, the control unit 25 controls driving or stopping of power conversion by the bidirectional AC / DC conversion unit 23.

  For example, when information that predicts weather in a region where the solar power generation system 11 is installed is provided to the solar power generation system 11 by a program executed in a server (not shown), the control unit 25 Information for predicting the weather is acquired via the unit 24. And the control unit 25 estimates the change of the solar radiation amount irradiated to the photovoltaic power generation panel 12 based on the information, and controls the charge with respect to the storage battery 13 according to the change of the solar radiation amount.

  Here, with reference to FIG. 2 thru | or FIG. 4, the basic concept about the charge control with respect to the storage battery 13 according to the change of the solar radiation amount of sunlight is demonstrated.

  FIG. 2 is a diagram illustrating current-voltage characteristics and power-voltage characteristics of the photovoltaic power generation panel 12.

In FIG. 2, the horizontal axis indicates the voltage [V] output from the photovoltaic power generation panel 12, the left vertical axis indicates the current [A] output from the solar power generation panel 12, and the right vertical axis. Indicates electric power [W] output from the photovoltaic power generation panel 12. Further, in FIG. 2, when the amount of sunlight irradiated to the photovoltaic power generation panel 12 is 1000 [W / m ² ], 800 [W / m ² ], and 600 [W / m ² ]. The current-voltage characteristics and the power-voltage characteristics are shown.

  For example, when a normal power conditioner is used, the power conditioner follows the maximum power point that is the peak of the curve indicated by the power voltage characteristic so that the output power of the photovoltaic power generation panel 12 is maximized. MPPT (Maximum Power Point Tracking) control.

  On the other hand, in the configuration of the photovoltaic power generation system 11 in FIG. 1, that is, in the configuration in which the photovoltaic power generation panel 12 is connected to the storage battery 13 without using a power conditioner or the like, the voltage of the storage battery 13 is dominant. Therefore, the voltage output from the photovoltaic power generation panel 12 is the voltage of the storage battery 13. For this reason, the voltage output from the photovoltaic power generation panel 12 does not necessarily become a voltage value that maximizes the output voltage.

  Further, as shown in FIG. 2, the voltage at the maximum power point of the photovoltaic power generation panel 12, that is, the voltage value that maximizes the power output from the photovoltaic power generation panel 12 is irradiated to the photovoltaic power generation panel 12. It changes according to the amount of sunlight irradiated. That is, as the amount of sunlight irradiated to the photovoltaic power generation panel 12 increases, the voltage value that maximizes the power output from the photovoltaic power generation panel 12 also increases.

  FIG. 3 shows a method of charging at a constant current and a constant voltage, and changes in voltage (V), changes in charging current (CA), and charging capacity when charging a storage battery 13 having rated capacities of 1C and 0.5C. It is a figure which shows the change of (CAh).

  As shown in FIG. 3, the voltage of the storage battery 13 increases as the charge capacity (remaining amount) of the storage battery 13 increases. That is, the voltage of the storage battery 13 increases as the charging proceeds.

  Thus, the voltage value which maximizes the electric power output from the photovoltaic power generation panel 12 increases as the charging of the storage battery 13 progresses by utilizing the tendency that the voltage of the storage battery 13 increases as the charging of the storage battery 13 progresses. By charging at such timing, the storage battery 13 can be charged with a voltage approximate to the voltage at the maximum power point. Thereby, the storage battery 13 can be charged efficiently.

  That is, the voltage value that maximizes the power output from the photovoltaic power generation panel 12 increases as the amount of sunlight irradiated to the photovoltaic power generation panel 12 increases (see FIG. 2). The storage battery 13 can be efficiently charged by starting the charging of the storage battery 13 when it is predicted that the amount of sunlight irradiated to the power generation panel 12 will increase.

  With reference to FIG. 4, an example of charging when the amount of solar radiation tends to increase and an example of charging when the amount of solar radiation tends to decrease will be described.

  FIG. 4 shows current-voltage characteristics and power-voltage characteristics of the photovoltaic power generation panel 12 as in FIG.

  In FIG. 4, a voltage V0 indicates an initial voltage when charging of the storage battery 13 is started, a voltage V1 indicates an intermediate voltage during charging of the storage battery 13, and a voltage V2 indicates the voltage of the storage battery 13. It shows the final voltage when charging is completed. That is, in FIG. 4, the storage battery is charged until charging starts from the initial voltage V0 (for example, about 19 V), passes through the intermediate voltage V1 (for example, about 20 V), and reaches the final voltage V2 (for example, about 21 V). 13 shows an example in which charging is performed.

The left side of FIG. 4 shows an example of charging when the amount of solar radiation tends to increase in the order of 600 [W / m ² ], 800 [W / m ² ], and 1000 [W / m ² ]. ing. When charging is started when the solar radiation amount tends to increase in this way, the solar radiation panel 12 corresponds to the initial voltage V0 of the storage battery 13 and the solar radiation amount is 600 [W / m ² ]. The charging is started with the electric power W0 output from the photovoltaic power generation panel 12 in accordance with the electric power voltage characteristics.

Thereafter, as the charging proceeds, the amount of solar radiation increases, and is output from the photovoltaic power generation panel 12 according to the power voltage characteristic when the amount of solar radiation is 800 [W / m ² ] corresponding to the intermediate voltage V1 of the storage battery 13. Charging is performed with the electric power W1. Then, as the charging proceeds further, the amount of solar radiation increases, corresponding to the final voltage V2 of the storage battery 13, and output from the photovoltaic power generation panel 12 according to the power voltage characteristics when the amount of solar radiation is 1000 [W / m ² ]. Charging is performed with the electric power W2.

  Thus, when charging is started when the amount of solar radiation tends to increase, the voltage of the storage battery 13 increases as the charging proceeds, and the voltage value that maximizes the power output from the photovoltaic power generation panel 12 Also rises. Therefore, the storage battery 13 is charged at a voltage approximate to the voltage at the maximum output point.

On the other hand, the right side of FIG. 4 shows an example of charging when the amount of solar radiation tends to decrease in the order of 1000 [W / m ² ], 800 [W / m ² ], and 600 [W / m ² ]. It is shown. When charging is started when the solar radiation amount tends to decrease in this way, when the solar radiation amount is 1000 [W / m ² ] corresponding to the initial voltage V 0 of the storage battery 13 from the photovoltaic power generation panel 12. Charging is started with power W0 ′ output from the photovoltaic power generation panel 12 in accordance with the power voltage characteristics. Here, as shown in FIG. 4, the electric power W0 ′ is lower than the electric power W2 and deviates from the maximum output point.

Thereafter, as the charging proceeds, the amount of solar radiation decreases, and is output from the photovoltaic power generation panel 12 according to the power voltage characteristic when the amount of solar radiation is 800 [W / m ² ] corresponding to the intermediate voltage V1 of the storage battery 13. Charging is performed with electric power W1 ′. Then, as the charging further proceeds, the amount of solar radiation decreases, and output from the photovoltaic power generation panel 12 according to the power voltage characteristic when the amount of solar radiation is 600 [W / m ² ] corresponding to the final voltage V2 of the storage battery 13. Charging is performed with the electric power W2 ′. Here, as shown in FIG. 4, the electric power W2 ′ is lower than the electric power W0 and deviates from the maximum output point.

  Thus, if charging is started when the amount of solar radiation tends to decrease, the storage battery 13 is not charged at a voltage approximate to the voltage at the maximum output point, and charging starts when the amount of solar radiation tends to increase. The storage battery 13 is charged with lower power than when the battery is used.

  In other words, when charging starts when the amount of solar radiation tends to increase, the voltage approximates the voltage at the maximum output point compared to when charging starts when the amount of solar radiation tends to decrease. The storage battery 13 can be charged for a long time. Therefore, the storage battery 13 can be charged more efficiently by starting charging when the amount of solar radiation tends to increase.

  Based on the above, the control unit 25 predicts a change in the amount of solar radiation applied to the photovoltaic power generation panel 12 based on the information for predicting the weather, and sunlight sunshine to the photovoltaic power generation panel 12. When it is estimated that the amount increases, that is, the voltage value that maximizes the power output from the photovoltaic power generation panel 12 is increased, the charging control is performed so that the storage battery 13 starts to be charged.

  FIG. 5 is a flowchart illustrating a process in which the control unit 25 of the power control device 14 of FIG. 1 determines the start of charging of the storage battery 13.

  For example, when it is detected that the solar power generation panel 12 is irradiated with sunlight and power generation is possible and output of electric power is started, the process is started. Control is performed to communicate with each other. The communication unit 24 performs communication via a network and acquires information (so-called weather forecast information or the like) for predicting the weather in the area where the solar power generation system 11 is installed.

  After the process of step S11, the process proceeds to step S12, and the control unit 25 calculates the amount of sunlight for the photovoltaic power generation panel 12 based on the information that predicts the weather acquired by the communication unit 24 in step S11 and the current time. Predict changes.

  For example, in the morning time zone, the control unit 25, when the information for predicting the weather indicates that clear sky continues in the area where the solar power generation system 11 is installed, the sunshine for the solar power generation panel 12 Expect the amount to increase. Moreover, the control unit 25, when the information for predicting the weather in the daytime time zone shows that the area where the photovoltaic power generation system 11 is installed changes from cloudy to sunny, the photovoltaic power generation panel 12 The amount of sunshine is expected to increase. In addition, the control unit 25 is in the evening time zone, or when the information predicting the weather indicates that the area where the solar power generation system 11 is installed changes from sunny to cloudy or rainy. The amount of sunshine for the photovoltaic power generation panel 12 is predicted to decrease.

  In step S13, is the control unit 25 estimated from the prediction result in step S12 that the voltage value that maximizes the power output from the photovoltaic power generation panel 12, that is, the voltage value at the maximum output point increases? Determine whether or not.

  For example, the control unit 25 estimates that the voltage value at the maximum output point increases when it is predicted that the amount of sunlight for the photovoltaic power generation panel 12 will increase in step S12. On the other hand, for example, when it is predicted that the amount of sunlight for the photovoltaic power generation panel 12 does not change or the amount of sunlight for the photovoltaic power generation panel 12 decreases in step S12, the control unit 25 determines that the voltage value of the maximum output point is Estimated not to rise.

  In step S13, when the control unit 25 estimates that the voltage value at the maximum output point does not increase (when it is not estimated that the voltage value at the maximum output point increases), the process proceeds to step S14.

  In step S <b> 14, the control unit 25 causes the bidirectional AC / DC conversion unit 23 to perform power conversion, and disconnects the connection between the photovoltaic power generation panel 12 and the storage battery 13 by opening the switch 22 (already disconnected. If so, continue cutting). As a result, the DC voltage power generated in the photovoltaic power generation panel 12 is supplied to the bidirectional AC / DC converter 23 and converted into AC voltage power, and then output to the outside through the distribution board. . After the process of step S14, the process returns to step S11. At this time, after waiting for a predetermined period to elapse, the control unit 25 performs control so that communication is performed with respect to the communication unit 24, and thereafter the same processing is repeated.

  On the other hand, when the control unit 25 estimates in step S13 that the voltage value at the maximum output point increases, the process proceeds to step S15.

  In step S <b> 15, the control unit 25 stops the power conversion by the bidirectional AC / DC conversion unit 23 and connects the photovoltaic power generation panel 12 and the storage battery 13 with the switch 22 in a closed state. Thereby, the electric power generated in the solar power generation panel 12 is directly supplied to the storage battery 13 via the diode 21 and the switch 22 and charging of the storage battery 13 is started. After the process of step S15, the process for determining the start of charging of the storage battery 13 is terminated.

  As described above, in the solar power generation system 11, the control unit 25 determines to start charging the storage battery 13 when it is estimated that the voltage value that maximizes the power output from the solar power generation panel 12 increases. As described with reference to FIG. 4, the storage battery 13 can be charged for a long time with a voltage approximate to the voltage at the maximum power point. Thereby, when the amount of sunshine does not change or when the amount of sunshine decreases, the storage battery 13 can be charged more efficiently than when charging of the storage battery 13 is started.

  Further, in the solar power generation system 11, power is directly supplied from the solar power generation panel 12 to the storage battery 13 without being converted by a power conditioner, a DC / DC converter, or the like. There is no loss due to conversion efficiency of DC / DC converters.

  Therefore, in the charging method of the photovoltaic power generation system 11, charging can be performed with higher efficiency compared to a charging method in which charging is performed via a power conditioner, a DC / DC converter, or the like. Moreover, since the configuration of the solar power generation system 11 can be relatively simplified as compared with the solar power generation system that performs charging via a power conditioner, a DC / DC converter, or the like, space saving and low cost can be achieved. And standby power can be reduced. Furthermore, the charging method of the photovoltaic power generation system 11 is advantageous when the photovoltaic power generation panel 12 and the power control device 14 are sold as a set.

  Here, with reference to FIG. 6 thru | or FIG. 8, the result of the simulation performed about the relationship between the change of the amount of sunlight and charging efficiency is demonstrated.

  FIG. 6 shows conditions when simulation is performed.

  As the photovoltaic power generation panel 12, the simulation was performed under the condition that 18 solar cells were connected and used. In addition, the connection configuration of solar cells is a configuration in which nine solar cells are connected in series and two cell rows are connected in parallel. For example, the output power of one cell is 0.153 kW. Then, the photovoltaic power generation panel 12 has an output power of 2.75 kW (= 0.153 × 18).

  Moreover, as the storage battery 13, the simulation was performed on condition that 48 lithium ion storage batteries are connected in series. Further, as the charging characteristics of the storage battery 13, a 7.5 kWh charging curve is used, the initial voltage V0 is 166.1V, the intermediate voltage V1 is 181.5V, and the final voltage V2 is 196.88V.

The amount of solar radiation was in the range of 600 to 1000 W / m ² , and simulation was performed under the first to fourth conditions. In the first condition, the amount of sunlight was constant at 800 W / m ² , and in the second condition, the amount of sunlight was constant at 1000 W / m ² . In the third condition, the amount of sunlight is assumed to be constant at 1000 W / m ² after changing from 600 W / m ² to 1000 W / m ² in 3.5 hours. In the fourth condition, the amount of sunlight is from 1000 W / m ^2. After changing to 600 W / m ² in 3.5 hours, it became constant at 600 W / m ² .

  A storage battery when the solar power generation panel 12 and the storage battery 13 are directly connected with the amount of sunshine under the first to fourth conditions, and the storage battery 13 is charged with the power generated by the solar power generation panel 12. Thirteen voltage changes were determined by simulation.

FIGS. 7A to 7D show the results of simulation with the amount of sunshine under the first to fourth conditions. 7A to 7D, the horizontal axis represents time, the left vertical axis represents voltage (V), and the right vertical axis represents solar radiation (W / m ² ). 7A to 7D show changes in the voltage (PV MPPT voltage) that is the maximum output point when MPPT control is performed, along with changes in the voltage of the storage battery 13 obtained by simulation.

  As shown in FIG. 7, when charging is performed under the third condition, the change in the voltage of the storage battery 13 is the one closest to the change in the PV MPPT voltage, compared with the case where charging is performed under other conditions. It becomes. Since the PV MPPT voltage is a voltage controlled so that the output power of the photovoltaic power generation panel 12 is maximized, the maximum output power from the photovoltaic power generation panel 12 depends on the voltage when charging is performed under the third condition. Power close to can be obtained. That is, from this simulation result, it can be said that by performing charging under the third condition, the storage battery 13 is charged more efficiently than when charging under other conditions.

  FIG. 8 shows the charging efficiency obtained by the simulation performed with the amount of sunlight under the first to fourth conditions.

  As shown in FIG. 8, the charging efficiency [%] is obtained by multiplying the value obtained by dividing “the power used for charging the storage battery” by “the power that can be originally obtained from the photovoltaic power generation panel (by MPPT control)” by 100. Is required.

  The charging efficiency obtained by the simulation was 98.9% under the first condition, 99.1% under the second condition, 99.5% under the third condition, and 97.7% under the fourth condition. Thus, the highest charging efficiency was required under the third condition.

  In the present embodiment, the control unit 25 makes a determination to start charging the storage battery 13 based on the change in the amount of solar radiation. In addition to the change in the amount of solar radiation, for example, The start of charging of the storage battery 13 may be determined with reference to the temperature of the solar power generation panel 12.

  That is, when the temperature of the solar power generation panel 12 increases, the power generation efficiency decreases and the output voltage tends to decrease. Accordingly, the control unit 25 is configured so that the temperature of the solar power generation panel 12 is not higher than a predetermined temperature at which the power generation efficiency of the solar power generation panel 12 is reduced to a predetermined reference value or lower, that is, lower than the predetermined temperature. When it is, charge control which starts charge to the storage battery 13 can be performed. Thereby, the storage battery 13 can be charged with higher efficiency. In this case, in order to detect the temperature of the photovoltaic power generation panel 12, a temperature sensor is provided in the photovoltaic power generation panel 12, or the control unit 25 predicts the weather acquired by the communication unit 24 (for example, the temperature) The temperature of the photovoltaic power generation panel 12 can be estimated from the information).

  In addition, for example, information that predicts the change in the amount of sunlight applied to the solar power generation system 11 at a location where the solar power generation system 11 is installed is provided to the solar power generation system 11 by a program executed in a server (not shown). You may do it. In this case, the control unit 25 acquires information predicting a change in the amount of sunlight through the communication unit 24, and does not predict a change in the amount of sunlight by the control unit 25 itself, and performs charge control according to the information. be able to.

  Further, for example, the control unit 25 may charge the storage battery 13 in a time zone (for example, in the morning) in which an increase in the amount of sunlight is estimated according to only the information indicating the time.

  Thus, the control unit 25 is not limited to performing charging control for the storage battery 13 using information for predicting the weather. That is, the control unit 25 can perform charging control for the storage battery 13 based on various conditions such as information predicting a change in the amount of sunlight, information indicating time, the temperature of the photovoltaic power generation panel 12, and the like. From this information, when it is estimated that the voltage value that maximizes the power output from the photovoltaic power generation panel 12 is increased, the charging control can be performed so as to start charging the storage battery 13.

  The control unit 25 includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), a flash memory (for example, an EEPROM (Electronically Erasable and Programmable Read Only Memory)), and the like. The storage battery 13 is charged by loading a program stored in the ROM or flash memory into the RAM and executing the program. Note that the program executed by the CPU can be downloaded to the flash memory and updated as appropriate in addition to those stored in the ROM and the flash memory in advance.

  Note that the processes described with reference to the flowcharts described above do not necessarily have to be processed in chronological order in the order described in the flowcharts, but are performed in parallel or individually (for example, parallel processes or objects). Processing). The program may be processed by one CPU, or may be distributedly processed by a plurality of CPUs.

  Furthermore, in the present embodiment, the power generation system using the solar power generation panel 12 as a power generation unit has been described. However, the present technology uses the natural energy such as wind power generation in addition to the solar power generation panel 12 to generate power. This can be applied to a power generation system that uses power generated by the power generation means.

  The embodiment of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the present invention.

  DESCRIPTION OF SYMBOLS 11 Photovoltaic power generation system, 12 Photovoltaic power generation panel, 13 Storage battery, 14 Power control apparatus, 21 Diode, 22 Switch, 23 Bidirectional AC / DC conversion part, 24 Communication part, 25 Control unit

Claims (6)

Estimating means for estimating whether or not the voltage value that maximizes the power output from the power generating means that generates power using natural energy increases;
When the estimation means estimates that the voltage value will rise, charging start means for starting charging the storage means for the power generated by the power generation means ;
A charge control device comprising: a power conversion unit that converts and outputs power output from the power generation means only when the power generated by the power generation means is not charged in the power storage means . The power generation means is a solar power generation means for generating power in response to sunlight irradiation,
Acquisition means for acquiring information for predicting the weather;
A predicting unit that predicts a change in the amount of solar radiation irradiated to the solar power generation unit based on the information acquired by the acquiring unit;
The said estimation means estimates that the said voltage value will rise when it is estimated that the solar radiation amount irradiated to the said photovoltaic power generation means will increase in the prediction result by the said prediction means. Charge control device. The charge control device according to claim 2, wherein the predicting unit predicts a change in the amount of solar radiation applied to the solar power generation unit based on time along with information for predicting the weather. The charging control device according to claim 1, wherein the charging start unit starts charging the storage unit when the temperature of the solar power generation unit is equal to or lower than a predetermined temperature. Estimate whether the voltage value that maximizes the power output from the power generation means that uses natural energy to generate power increases,
When it is estimated that the voltage value increases, charging of the power storage means generated by the power generation means is started ,
A power control method comprising a step of converting and outputting the power output from the power generation means only when the power generated by the power generation means is not charged in the power storage means . Power generation means for generating power using natural energy;
Storage means for charging power;
Estimating means for estimating whether or not the voltage value that maximizes the power output from the power generating means rises;
A charging start unit that starts charging the storage unit with the power generated by the power generation unit when the estimation unit estimates that the voltage value increases ;
A photovoltaic power generation system comprising: a power conversion unit that converts and outputs power output from the power generation means only when the power generated by the power generation means is not charged in the power storage means .

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