JP2017195728A - Power generation system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power generation system in which a storage battery system is installed together that suppresses progression of deterioration of the storage battery even if a large fluctuation occurs in generated power.SOLUTION: The power generation system includes: a power generation device; a storage battery device having a storage battery, for suppressing fluctuations in system output power; and an output control device having a determination unit for determining whether the fluctuation in the generated power increases. Then, when it is determined by the determination unit that the fluctuation of the generated power becomes large, operation of the power generation device and the storage battery device is stopped during a time period in which the fluctuation of the generated power becomes large.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a power generation system.

  In recent years, introduction of a photovoltaic power generation system has been promoted in consideration of environmental problems and the like. However, since the output power of solar power generation varies greatly depending on the weather, it may cause voltage fluctuations and frequency fluctuations of the power system linked to the solar power generation system. As a countermeasure, a technique has been proposed in which a storage battery system for suppressing fluctuations in generated power is provided in addition to a photovoltaic power generation system, and the output power to the power system is smoothed by charging and discharging of the storage battery system. As this conventional technique, for example, Patent Document 1 discloses a technique related to a charge / discharge control method of a photovoltaic power generation system.

  Patent Document 1 states that “a photovoltaic power generation system is connected to an electric power system and generates power using sunlight, power storage means capable of storing electric power, and wiring between the electric power generation apparatus and the electric power system. And a charge / discharge control unit for controlling charge / discharge of the power storage means ”. Patent Document 1 states that “the charge / discharge control unit has a change amount when the generated power of the power generator changes from the first power to the second power is equal to or greater than a predetermined change amount, and from the first power. There is also a description that “the charge / discharge control of the storage means is performed when the second power does not return to the generated power in the vicinity of the first power within the standby time from the time when the power is changed to the second power”.

JP 2011-097817 A

  In a photovoltaic power generation system provided with a storage battery system, for example, when the maximum power generation operation and the zero output operation are repeated, that is, when large fluctuations in generated power occur repeatedly, the following problems occur. Can occur. In this case, since intense charging / discharging is repeated in the storage battery, there arises a problem that the deterioration of the storage battery proceeds.

  The present invention has been made to solve this problem. An object of the present invention is to provide a technology capable of suppressing the progress of deterioration of a storage battery even if a large fluctuation in generated power occurs in a power generation system provided with a storage battery system.

  In order to solve the above-described problems, in the present invention, a power generation device, a storage battery device that suppresses fluctuations in system output power that is the sum of generated power output from the power generation device and charge / discharge power of the storage battery, and an output control device A power generation system comprising: In the power generation system of the present invention, the output control device includes a determination unit that determines whether or not the fluctuation of the generated power becomes large.

  In the first power generation system of the present invention, the output control device operates the power generation device and the storage battery device during a time period when the variation in the generated power increases when the determination unit determines that the variation in the generated power increases. To stop. In the second power generation system of the present invention, when the above determination result is obtained, the output control device is configured so that the system output power is output at a predetermined value in a time zone in which the fluctuation of the generated power increases. In addition, operation control of the power generation device and the storage battery device is performed. Furthermore, in the third power generation system of the present invention, when the above determination result is obtained, the output control device causes the storage battery device to generate the generated power generated by the power generation device during a time period when the fluctuation of the generated power increases. Operation control of the power generation device and the storage battery device is performed so that all are charged.

  According to the power generation system of the present invention configured as described above, it is possible to suppress the progress of deterioration of the storage battery even if a large fluctuation in generated power occurs.

It is a block diagram which shows the whole structure of the solar energy power generation system which concerns on the 1st Embodiment of this invention. It is a block diagram which shows the internal structure of the integrated controller of the solar energy power generation system which concerns on 1st Embodiment. It is a block diagram which shows the internal structure of the system target output calculating part of the solar energy power generation system which concerns on 1st Embodiment. It is a figure for demonstrating the output control example of the system output in the solar energy power generation system which concerns on 1st Embodiment. It is a flowchart which shows the procedure of the correction process of the target value of the system output in the solar energy power generation system which concerns on 1st Embodiment. It is a figure for demonstrating the 1st output control example of the system output in the solar energy power generation system which concerns on the 2nd Embodiment of this invention. It is a figure for demonstrating the 2nd output control example of the system output in the solar energy power generation system which concerns on 2nd Embodiment. It is a block diagram which shows the internal structure of the integrated controller of the solar energy power generation system which concerns on the 4th Embodiment of this invention.

  Hereinafter, the configuration and operation of a power generation system according to various embodiments of the present invention will be specifically described with reference to the drawings. In the following various embodiments, a solar power generation system provided with a storage battery system will be described as an example of the power generation system.

<First Embodiment>
[Entire configuration of photovoltaic power generation system]
FIG. 1 is a block diagram showing the overall configuration of the photovoltaic power generation system according to the first embodiment of the present invention. As shown in FIG. 1, the solar power generation system 100 includes a power generation device unit 1 (power generation device), a storage battery system 2, and a power generation amount prediction unit 3. In addition, although this embodiment demonstrates the structural example in which the electric power generation amount prediction part 3 is contained in the solar power generation system 100, this invention is not limited to this, The electric power generation amount prediction part 3 is the exterior of the solar power generation system 100. May be provided.

  The power output end of the power generator unit 1 is electrically connected to an external power system 200. In addition, the charge / discharge end of the electric power of the storage battery system 2 (storage battery device 6 described later) is electrically connected in the middle of the wiring (connection point cp in FIG. 1) connecting the power output end of the power generation unit 1 and the power system 200. Connected to. Therefore, in the photovoltaic power generation system 100 of the present embodiment, charge / discharge power Pbatt described later input / output by the storage battery system 2 is added to or subtracted from the generated power Ppv output from the power generator unit 1 at the connection point cp. Is done. The sum of the generated power Ppv and the charge / discharge power Pbatt is supplied to the power system 200 as the system output Psys (system output power) of the solar power generation system 100.

  The power generation amount prediction unit 3 predicts future fluctuations of the generated power Ppv based on information such as weather, for example, and stores the predicted fluctuation information of the generated power Ppv (hereinafter referred to as “output predicted value Ppv_pre”) as a storage battery. The data is output to the overall controller 10 described later in the system 2. The output predicted value Ppv_pre may be only a predicted value after a predetermined time (one sampling time ahead) from the current time, or a plurality of predictions obtained at predetermined sampling time intervals from the current time over a specific period. It may be a value.

  Moreover, as long as the structure of the electric power generation amount prediction part 3 is a structure which can predict the fluctuation | variation of the future generation electric power Ppv, arbitrary structures are applicable. For example, the configuration of the power generation amount prediction unit 3 is a configuration for predicting future fluctuations in the generated power Ppv using weather information on the installation location of the power generation unit 1 supplied from the outside (for example, the Japan Meteorological Agency or a weather related company). It may be. In addition, for example, the configuration of the power generation amount prediction unit 3 is, for example, installed in a place where the power generation unit 1 is installed, such as a meteorological information or the like (meteorological measuring instrument, camera, etc.) and transmitted from the device A configuration for predicting future fluctuations in the generated power Ppv based on the information may be used. Note that any method can be applied to the fluctuation prediction method of the generated power Ppv used in the power generation amount prediction unit 3 as long as it can predict the fluctuation of the future generated power Ppv.

[Configuration of power generation unit]
As shown in FIG. 1, the power generation device unit 1 includes a solar panel 4 and a solar power conditioner 5 (hereinafter referred to as “solar PCS 5”). In the power generation unit 1, the output end of the generated power of the solar panel 4 is electrically connected to the input end of the solar PCS 5, and the output end of the solar PCS 5 is electrically connected to the power system 200.

  The solar panel 4 generates power by converting sunlight into electric power. The generated power (DC power) generated by the solar panel 4 is output to the solar PCS 5. The solar panel 4 can be configured by, for example, connecting a plurality of silicon-based solar cells such as a single crystal silicon type, a polycrystalline silicon type, a microcrystalline silicon type, and an amorphous silicon type in series and parallel. The solar panel 4 may be configured by connecting a plurality of compound-type solar cells such as InGaAs, GaAs, and CIS (calcobarite) in series and parallel. Furthermore, in this embodiment, as a solar cell which comprises the solar panel 4, you may use organic type solar cells, such as a dye-sensitized solar cell and an organic thin film solar cell, for example.

  The PCS 5 for sunlight converts DC generated power output from the solar panel 4 into AC generated power Ppv, and supplies (outputs) the converted generated power Ppv to the power system 200. That is, the electric power generated by the solar panel 4 is supplied to the electric power system 200 via the solar PCS 5. Therefore, the generated power Ppv supplied to the power system 200 is limited by the capacity of the solar PCS 5.

[Configuration of storage battery system]
As shown in FIG. 1, the storage battery system 2 includes a storage battery device 6 and a power control device 7 (output control device). The storage battery system 2 smoothes and compensates for fluctuations in the generated power Ppv output from the power generation unit 1 by the charge / discharge operation of the storage battery device 6 (storage battery 8).

  The storage battery device 6 includes a storage battery 8 and a storage battery power conditioner 9 (hereinafter referred to as “storage battery PCS 9”). In the storage battery device 6, the charge / discharge terminal of the storage battery 8 is electrically connected to one input / output terminal of the storage battery PCS 9, and the other input / output terminal of the storage battery PCS 9 is connected to the power output terminal of the power generator unit 1 and the power system. 200 is electrically connected to a connection point cp on the wiring connecting the two. Note that the storage battery PCS 9 and the above-described sunlight PCS 5 may be referred to as grid-connected inverters.

  The storage battery 8 is composed of, for example, a lead storage battery, a lithium ion storage battery, a nickel / hydrogen storage battery, or the like.

  The storage battery PCS 9 converts the DC power output from the storage battery 8 to AC during discharging, and the converted power (discharge power) is on the wiring connecting the power output terminal of the power generator unit 1 and the power system 200. Output to the connection point cp. Thereby, electric power is discharged from the storage battery device 6 to the electric power system 200 side. Further, the storage battery PCS 9 converts the alternating current power (charging power) input from the connection point cp into direct current during charging, and outputs the converted power to the storage battery 8. Thereby, electric power is charged in the storage battery device 6. That is, the storage battery 8 performs a charge / discharge operation on the power system 200 via the storage battery PCS 9. Hereinafter, the discharge power and the charge power generated by the charge / discharge operation of the storage battery device 6 are collectively referred to as “charge / discharge power Pbatt”.

  The power control device 7 has a function (variation suppressing function) for suppressing (compensating) fluctuations in the system output Psys of the photovoltaic power generation system 100. For example, the fluctuation component of the generated power Ppv caused by the influence of a shade generated by clouds or the like is canceled (compensated) by the power control device 7 adjusting the charge / discharge power Pbatt, and the system output Psys is smoothed. Is done.

  As shown in FIG. 1, the power control device 7 includes an overall controller 10, a communication network 11 (such as the Internet), an external controller 12, and a terminal 13. In the power control apparatus 7, the overall controller 10 is communicably connected to the external controller 12 via the communication network 11, and the external controller 12 is connected to the terminal 13 via a serial bus or a parallel bus.

  In the power control device 7 having such a configuration, the operator can control the processing operation of the overall controller 10 via the external controller 12 installed at a location away from the photovoltaic power generation system 100. For example, when the operator operates the terminal 13, the general controller 10 can be accessed via the external controller 12, and various setting values necessary for various controls can be input. For example, the operator can display the state (operation status) of the photovoltaic power generation system 100 on the terminal 13. In the present embodiment, a configuration example in which the power controller 7 includes the external controller 12, the communication network 11, and the terminal 13 will be described. However, the present invention is not limited to this, and these configurations are not included in the power controller 7. It may be provided outside.

[General controller configuration and various control functions]
The overall controller 10 is composed of, for example, an arithmetic device such as a CPU (Central Processing Unit), and the power generation device unit 1 (solar PCS 5), the power generation amount prediction unit 3, and the storage battery device 6 (storage battery 8 and storage battery PCS 9). Each is electrically connected. The overall controller 10 controls not only various arithmetic controls necessary for controlling various operations of the storage battery device 6 described later, but also controls the overall operation of the photovoltaic power generation system 100. The overall controller 10 may be connected to each of the power generation device unit 1, the power generation amount prediction unit 3, and the storage battery device 6 via a communication network. In this case, the communication connection mode can be arbitrarily set, and for example, any mode of wireless communication and wired communication can be applied.

  The overall controller 10 acquires a monitor signal of the generated power Ppv measured by the solar PCS 5 (hereinafter referred to as “generated power monitor signal Ppv_fb”). The generated power monitor signal Ppv_fb may be measured by a power meter or the like provided separately from the solar PCS 5. Further, the overall controller 10 acquires the predicted output value Ppv_pre generated by the power generation amount prediction unit 3. Furthermore, the overall controller 10 also acquires a signal (hereinafter referred to as “SOC (State Of Charge) signal”) including information on the state of charge from the storage battery 8. The operation of acquiring these various signals (various information) by the overall controller 10 may be performed regularly or irregularly.

  The overall controller 10 performs various calculations for suppressing (compensating) power fluctuations based on the generated power monitor signal Ppv_fb input from the solar PCS 5 and the predicted output value Ppv_pre input from the power generation amount prediction unit 3. I do. Specifically, the overall controller 10 calculates target values (Psys, Plim, Psys_c in FIG. 4 described later) that serve as a guide for suppressing fluctuations in the system output Psys. Further, the overall controller 10 calculates a target value of the charge / discharge power Pbatt generated by the storage battery device 6 (hereinafter referred to as “charge / discharge target value Pbt”) based on the calculated target value of the system output Psys. . The internal configuration of the overall controller 10 for executing these operations will be described in detail later.

  The overall controller 10 outputs the calculated charge / discharge target value Pbt to the storage battery PCS 9. The storage battery PCS 9 (storage battery device 6) adjusts (controls) the charge / discharge power Pbatt for the power system 200 based on the charge / discharge target value Pbt input from the overall controller 10. Specifically, the storage battery PCS 9 (storage battery device 6) controls the charge / discharge power Pbatt to be the same value as the charge / discharge target value Pbt. Thereby, the system output Psys is controlled to be substantially the same value as the target value of the system output Psys.

  Furthermore, the overall controller 10 has a function of correcting the target value of the system output Psys based on the predicted output value Ppv_pre input from the power generation amount prediction unit 3 (target value correction function). In the present embodiment, when it is predicted that the fluctuation of the generated power Ppv will increase in the future based on the predicted output value Ppv_pre, the target output correction function is used to change the system output Psys at a fluctuation rate within an allowable range from that point. The process of reducing is started. In this embodiment, when the system output Psys (target value of the system output Psys) becomes zero by the operation of the target value correction function, finally, the entire photovoltaic power generation system 100 (the power generation unit 1 and the storage battery). Both systems 2) are stopped.

[Internal configuration of general controller]
FIG. 2 is a functional block diagram illustrating an internal configuration example of the overall controller 10. As shown in FIG. 2, the overall controller 10 includes a system target output calculation unit 20 including a smoothing processing unit 22 described later, and a difference calculation unit 21. One input end of the system target output calculation unit 20 is connected to the sunlight PCS 5, and the other input end is connected to the power generation amount prediction unit 3. The output end of the system target output calculation unit 20 is connected to the “+” side input end of the difference calculation unit 21. Further, the input end on the “−” side of the difference calculation unit 21 is connected to the sunlight PCS 5, and the output end of the difference calculation unit 21 is connected to the storage battery PCS 9.

  The system target output calculation unit 20 is based on the generated power monitor signal Ppv_fb input from the solar PCS 5 and the predicted output value Ppv_pre input from the power generation amount prediction unit 3 (control target of the system output Psys). Value). Next, the system target output calculation unit 20 outputs the calculated target value of the system output Psys (Psys, Plim, or Psys_c in FIG. 2) to the difference calculation unit 21. The internal configuration and specific calculation contents of the system target output calculation unit 20 will be described in detail later.

  Further, the system target output calculation unit 20 determines (predicts) whether or not the fluctuation of the generated power Ppv will increase in the future based on the input output predicted value Ppv_pre. When the fluctuation of the generated power Ppv is predicted to increase, the system target output calculation unit 20 starts the calculation control of the target value of the system output Psys from the normal calculation control and changes the target value at a predetermined change rate with time. Switch to arithmetic control to be changed.

  In the present embodiment, the target value of the system output Psys is calculated based on the generated power monitor signal Ppv_fb in a time zone in which the fluctuation of the generated power Ppv is small and the fluctuation of the system output Psys is within an allowable range (normal calculation) Control is performed). Hereinafter, the target value of the system output Psys calculated by the normal arithmetic control is referred to as “system target output Psys”.

  On the other hand, when the fluctuation of the generated power Ppv is predicted to increase, the target value of the system output Psys (hereinafter, referred to as the following) that changes at a predetermined change rate with time regardless of the fluctuation of the generated power monitor signal Ppv_fb. (Referred to as “corrected descending output Plim”). Therefore, when it is predicted that the fluctuation of the generated power Ppv will increase, the corrected decrease output Plim is output from the system target output calculation unit 20 to the difference calculation unit 21 as the target value of the system output Psys. The corrected decrease output Plim decreases with time at a rate of change within an allowable range of the system output Psys defined in the constraint condition.

  In this embodiment, when the corrected decrease output Plim decreases to a predetermined value (zero in this embodiment), the system target output calculation unit 20 thereafter sets the predetermined value to the target value of the system output Psys (hereinafter, “ Constant output as system target output Psys_c). The output operation of the system target output Psys_c is continued until it is determined that the calculation control of the target value of the system output Psys at the normal time is possible. Further, the output period of the system target output Psys_c (in this embodiment, the stop period of the solar power generation system 100) can be arbitrarily set according to, for example, the weather condition, the performance of the storage battery system 2, and the like.

  The difference calculation unit 21 calculates a difference signal obtained by subtracting the generated power monitor signal Ppv_fb input from the solar PCS 5 from the target value of the system output Psys input from the system target output calculation unit 20. And the difference calculating part 21 outputs the calculated difference signal to PCS9 for storage batteries as charging / discharging target value Pbt.

  FIG. 3 is a calculation block diagram showing an internal configuration example of the system target output calculation unit 20. As shown in FIG. 3, the system target output calculation unit 20 includes a smoothing processing unit 22 and a target value correction unit 23. The target value correction unit 23 includes a constraint condition storage unit 24, a fluctuation scale determination unit 25 (determination unit), and a correction amount calculation unit 26.

  The smoothing processing unit 22 performs a low-pass filter calculation (smoothing calculation) process such as a moving average method or a first-order lag method on the generated power monitor signal Ppv_fb input from the PCS 5 for sunlight. Then, the smoothing processing unit 22 outputs the smoothed signal to the target value correcting unit 23 as the basic value Psys0 of the system target output Psyst.

  The target value correcting unit 23 calculates the system output Psys based on the basic value Psys 0 input from the smoothing unit 22 and the output predicted value Ppv_pre input from the power generation amount predicting unit 3. At this time, for example, if it is determined that the basic value Psys0 needs to be corrected based on information such as the output predicted value Ppv_pre, the target value correcting unit 23 corrects the basic value Psys0 and outputs the corrected signal. It outputs to the difference calculation part 21 as a target value of system output Psys. On the other hand, when it is not necessary to correct the basic value Psys0, the target value correcting unit 23 outputs the basic value Psys0 as the system target output Psys to the difference calculating unit 21. In addition, the structure of each part which comprises the target value correction part 23, and the content of processing operation are as follows.

  The constraint condition storage unit 24 stores the constraint conditions defined for the supply mode of the system output Psys from the photovoltaic power generation system 100 to the power system 200. As one of the constraint conditions, for example, conditions such as a change amount (change rate) per unit time of the system output Psys can be cited. The rate of change of the system output Psys is a constraint condition determined in advance between a power selling company and a power transmission / distribution company, and the photovoltaic power generation system 100 supplies power to the power system 200 at a rate of change within the allowable range. Must be supplied.

  The fluctuation scale determination unit 25 calculates the fluctuation amount of the future generated power Ppv based on the predicted output value Ppv_pre input from the power generation amount prediction unit 3, and determines the fluctuation scale of the generated power Ppv (or system output Psys). To do. Then, the fluctuation scale determination unit 25 outputs a determination result (whether it is large) of the fluctuation scale of the generated power Ppv to the correction amount calculation unit 26.

  The correction amount calculation unit 26 is input from the smoothing processing unit 22 if necessary based on the determination result of the variation scale input from the variation scale determination unit 25 and the constraint condition stored in the constraint condition storage unit 24. The basic value Psys0 of the system target output Psys is corrected. Specifically, in the present embodiment, when the fluctuation scale determination unit 25 determines that the fluctuation of the generated power Ppv is large (when the fluctuation rate of the system output Psys exceeds the allowable range of the fluctuation rate defined by the constraint condition) The correction amount calculation unit 26 corrects the basic value Psys0. At this time, in the present embodiment, the correction amount calculation unit 26 calculates the corrected decrease output Plim that changes at a preset change rate as the target value of the corrected system output Psys regardless of the value of the basic value Psys0. To do. Note that the rate of change of the corrected descending output Plim is set to a value within an allowable range defined by the constraint conditions.

[Example of output control of system output Psys]
Here, an example of output control of the system output Psys by the overall controller 10 (example of calculation control of the target value of the system output Psys) by the overall controller 10 will be described with reference to FIG. FIG. 4 is a diagram illustrating a time change example of the target value of the system output Psys that is calculated and controlled by the overall controller 10 (system target output calculation unit 20). In the photovoltaic power generation system 100 of the present embodiment, when the fluctuation of the generated power Ppv is predicted to increase during system operation, and the corrected descending output Plim (target value of the system output Psys) becomes zero, the photovoltaic power generation The entire system 100 is stopped.

  In the example illustrated in FIG. 4, the time when the fluctuation of the generated power Ppv is predicted to be large is the time T1, the time when the power generation unit 1 is stopped is the time T2 (> T1), and the storage battery system 2 is stopped. An example in which the set time is time T3 (> T2) is shown. Moreover, the characteristic (curve) shown by the solid line in FIG. 4 is the time change characteristic of the generated power monitor signal Ppv_fb detected before time T2. A characteristic (curve) indicated by a dotted line in FIG. 4 is a time change characteristic of the generated power monitor signal Ppv_fb (generated power Ppv) predicted after time T2.

  In the output control example shown in FIG. 4, first, at time T <b> 1 during system operation, the fluctuation scale determination unit 25 of the system target output calculation unit 20 is based on the predicted output value Ppv_pre input from the power generation amount prediction unit 3. The fluctuation of the generated power Ppv is predicted to increase. When such a prediction result is obtained at time T1, the system target output calculation unit 20 switches the calculation control of the target value of the system output Psys from the calculation control of the system target output Psyst to the calculation control of the corrected descending output Plim.

  Prior to time T1, the target value of system output Psys (system target output Psys) is calculated based on generated power monitor signal Ppv_fb. Therefore, before time T1, the change characteristic of the system target output Psys (thick dotted line in FIG. 4) is the same as that of the generated power monitor signal Ppv_fb (solid line in FIG. 4). On the other hand, after time T1, the target value (corrected decrease output Plim) of the system output Psys is calculated based on a predetermined change rate (slope a) regardless of the change in the generated power monitor signal Ppv_fb. Therefore, after time T1, the change characteristic of the corrected descending output Plim (thick broken line in FIG. 4) is a characteristic that the corrected descending output Plim changes (decreases) linearly at a predetermined rate of change (slope a) with time. It becomes. That is, in the example illustrated in FIG. 4, the overall controller 10 forcibly switches the output control of the system output Psys to the output control in which the system output Psys decreases at the change rate of the slope a with time at time T1.

  Next, after time T1, the power generation unit 1 is first stopped at the timing (time T2) when the generated power monitor signal Ppv_fb and the corrected lowering output Plim become the same value. Therefore, although not shown in FIG. 4, the generated power monitor signal Ppv_fb (actual value) becomes zero after time T2.

  Next, after time T2, the corrected decrease output Plim further decreases and becomes zero, that is, when time T3 is reached, the storage battery system 2 is stopped, and the entire photovoltaic power generation system 100 is stopped. Since the entire photovoltaic power generation system 100 is stopped after time T3, the system target output calculation unit 20 also sets the target value of the system output Psys (system target output Psys_c) to zero (in FIG. 4). (Refer to the dashed line).

  In the example shown in FIG. 4, the change rate (slope a) of the corrected fall output Plim can be set to an arbitrary change rate as long as it is within the allowable range defined by the constraint conditions. In the example shown in FIG. 4, the example in which the change rate of the corrected decrease output Plim in the period from the time T1 to the time T3 has been described, but the present invention is not limited to this. For example, at a predetermined timing in a period from time T1 to time T3, the change rate of the corrected descending output Plim may be changed as appropriate within an allowable range defined by the constraint conditions. Furthermore, although the example shown in FIG. 4 demonstrated the example which changes (decreases) the correction | amendment fall output Plim linearly with time, this invention is not limited to this. For example, a configuration (function) for sequentially updating the rate of change of the corrected descending output Plim may be provided so that the corrected descending output Plim changes (decreases) in a curve with time.

  In the example shown in FIG. 4, the example in which the power generation device unit 1 stops at the timing (time T2) at which the generated power monitor signal Ppv_fb and the corrected decrease output Plim become the same value after the time T1 has been described. The invention is not limited to this. The timing for stopping the power generation unit 1 can be set to any timing as long as it is after the time T1 and before the timing (time T3) when the storage battery system 2 is stopped. For example, the timing for stopping the power generation device unit 1 may be set at the time T1 or may be set at the time T3. In the latter case, both the power generation unit 1 and the storage battery system 2 are stopped simultaneously at the timing when the corrected lowering output Plim becomes zero.

[System output target value correction processing example]
Next, the correction process of the target value of the system output Psys will be described with reference to FIG. FIG. 5 is a flowchart showing a procedure for correcting the target value of the system output Psys by the overall controller 10 (system target output computing unit 20).

  First, the system target output calculation unit 20 acquires data necessary for predicting fluctuations in the generated power Ppv (step S11). Specifically, the system target output calculation unit 20 calculates the predicted fluctuation amount ΔPpv_pre of the generated power Ppv based on the output predicted value Ppv_pre input from the power generation amount prediction unit 3.

  In the present embodiment, as the output predicted value Ppv_pre used in step S11, a predicted value one sample time ahead of the current time may be used, or at a predetermined sampling time interval over a specific period after the current time. You may use the acquired some predicted value. In the former case, the predicted fluctuation amount ΔPpv_pre can be set to a value obtained by subtracting the generated power monitor signal Ppv_fb at the current time from the output predicted value Ppv_pre one sampling time ahead. On the other hand, in the latter case, the predicted fluctuation amount ΔPpv_pre can be set to, for example, the maximum value or the minimum value of the predicted fluctuation amount ΔPpv_pre calculated separately at each sampling time. In the latter case, the predicted fluctuation amount ΔPpv_pre may be, for example, the difference between the maximum value and the minimum value among the plurality of predicted output values Ppv_pre acquired over a specific period.

  Next, the system target output calculation unit 20 (variation scale determination unit 25) determines whether or not the fluctuation of the generated power Ppv will increase in the future (step S12). Specifically, the fluctuation scale determination unit 25 determines whether or not the predicted fluctuation amount ΔPpv_pre is equal to or larger than a predetermined fluctuation amount. If the predicted fluctuation amount ΔPpv_pre is equal to or larger than the predetermined fluctuation amount, power generation will be performed in the future. It determines with the fluctuation | variation of electric power Ppv becoming large. Further, the threshold value (predetermined fluctuation amount) of the predicted fluctuation amount ΔPpv_pre used in the determination process in step S12 can be determined as appropriate based on, for example, the allowable range of the fluctuation rate of the system output Psys. In the present embodiment, it is desirable to set the threshold value of the predicted fluctuation amount ΔPpv_pre to, for example, a value of about 65% or more of the power generation predetermined rated output.

  In step S12, when the system target output calculation unit 20 determines that the fluctuation of the generated power Ppv will not increase in the future (when step S12 is NO determination), the system target output calculation unit 20 sets the target of the system output Psys. The value correction process is terminated. In this case, the basic value Psys0 calculated by the smoothing processing unit 22 is output as the target value of the system output Psys (system target output Psys).

  On the other hand, when the system target output calculation unit 20 determines in step S12 that the fluctuation of the generated power Ppv will increase in the future (when step S12 is YES determination), the system target output calculation unit 20 performs the process of step S13. I do. In this process, the system target output calculation unit 20 switches the calculation control of the target value of the system output Psys from the calculation control of the system target output Psys to the calculation control of the corrected lowering output Plim.

  Next, the system target output calculation unit 20 calculates a corrected decrease output Plim that is a target value of the next system output Psys, and outputs the calculated correction decrease output Plim to the difference calculation unit 21 in the overall controller 10 ( Step S14). In this process, the system target output calculation unit 20 uses a preset change rate of the corrected decrease output Plim (inclination “a” in FIG. 4) to obtain a corrected decrease output that becomes the target value of the next system output Psys. Calculate Plim. In this process, the initial value of the corrected lowering output Plim is the system target output Psys when step S12 is YES.

  Next, the system target output calculation unit 20 determines whether or not the corrected decrease output Plim calculated in step S14 is a predetermined value (step S15). In this embodiment, in this process, the system target output calculation unit 20 determines whether or not the corrected lowering output Plim is zero.

  In step S15, when the system target output calculation unit 20 determines that the corrected decrease output Plim is not a predetermined value (when step S15 is NO), the system target output calculation unit 20 returns the process to step S14, The processing is repeated after S14. In other words, in the present embodiment, the processes of step S14 and step S15 are repeated until the corrected decrease output Plim becomes zero. In step S15, when the system target output calculation unit 20 determines that the corrected decrease output Plim is a predetermined value (step S15 is YES determination), the system target output calculation unit 20 sets the target of the system output Psys. The value correction process is terminated.

[Effects]
As described above, in the solar power generation system 100 of the present embodiment, when the fluctuation of the generated power Ppv becomes large, the solar power generation system 100 is finally stopped in the time zone when the fluctuation of the generated power Ppv becomes large. When such output control of the system output Psys is performed, the charging / discharging operation of the storage battery 8 is stopped in a time zone in which the fluctuation of the generated power Ppv becomes large, so that the progress of deterioration of the storage battery 8 can be suppressed. .

  In general, when the fluctuation of the generated power Ppv increases, the fluctuation of the system output supplied to the power system from the solar power generation system may exceed the allowable range of the power system due to insufficient charge / discharge capability of the storage battery system. There is sex. When such a situation occurs, it is necessary to take measures such as stopping power generation, which may reduce the amount of electricity sold. However, in the present embodiment, the system output Psys is reduced while suppressing the fluctuation of the system output Psys within an allowable range during the period from when the fluctuation of the generated power Ppv is expected to increase until the photovoltaic power generation system 100 stops. Let In this period, power is supplied from the solar power generation system 100 to the power system 200. Therefore, in the present embodiment, even when a situation in which the generated power Ppv fluctuates becomes large, deviation from the allowable range of fluctuations in the system output Psys can be prevented during this period and the amount of power sold can be ensured. .

<Second Embodiment>
In the first embodiment, when the fluctuation of the generated power Ppv is predicted to increase, the target value (corrected lowering output Plim) of the system output Psys is lowered to zero and the entire photovoltaic power generation system 100 is stopped. Although the configuration has been described, the present invention is not limited to this. For example, when the fluctuation of the generated power Ppv is predicted to increase, the target value of the system output Psys is changed to a predetermined value (predetermined constant value) greater than zero and then the target value of the system output Psys is kept constant at a predetermined value. The output may be controlled by using the above. In this case, it is not necessary to stop the solar power generation system (the power generation unit and the storage battery system).

  In the second embodiment, a solar power generation system capable of performing such output control of the system output Psys will be described. In addition, since the structure of the solar power generation system of this embodiment is the same as that of the said 1st Embodiment (refer FIGS. 1-3), description of the structure of a solar power generation system is abbreviate | omitted here. . In the following, each component will be described with the same reference numerals as those in the first embodiment.

[First Output Control Example of System Output Psys]
A first output control example of the system output Psys by the overall controller 10 of the present embodiment will be described with reference to FIG. FIG. 6 is a diagram illustrating a time change example of the target value of the system output Psys that is calculated and controlled by the overall controller 10 (system target output calculation unit 20).

  In the first output control example shown in FIG. 6, when it is predicted that the fluctuation of the generated power Ppv will increase, the minimum value of the generated power Ppv predicted in the time zone in which the fluctuation of the generated power Ppv increases (hereinafter, “prediction” Is set as the final value of the corrected fall output Plim. Further, in FIG. 6, the time when the fluctuation of the generated power Ppv is predicted to be large is time T4, and the start time of the arithmetic control with the target value of the system output Psys being the final value (system target output Psys_c) is the time An example of T5 (> T4) is shown.

  In the example shown in FIG. 6, when it is predicted that the fluctuation of the generated power Ppv (see the solid line in FIG. 6) will increase at time T4, the calculation control of the target value of the system output Psys is the same as that in the first embodiment. Similarly, the calculation control of the corrected lowering output Plim is switched. At this time, a predicted minimum value is specified from a plurality of output predicted values Ppv_pre output from the power generation amount prediction unit 3 and obtained at predetermined sampling time intervals over a specified time, and the predicted minimum value is corrected and decreased. It is set as the final value (predetermined value) of the output Plim.

  Next, after it is predicted that the fluctuation of the generated power Ppv will increase (after time T4), the corrected decrease output Plim is reduced to the predicted minimum value (predetermined value) at a predetermined change rate (slope b) with time (FIG. 6). (See the thick dashed line in the middle). That is, in the example illustrated in FIG. 6, at time T4, the overall controller 10 forcibly switches the output control of the system output Psys to output control in which the system output Psys decreases with the change rate of the slope b with time.

  Note that the change rate (slope b) of the corrected descending output Plim in this example can be set to an arbitrary change rate (slope) as long as it is within the allowable range defined by the constraint conditions. Further, the change rate (slope b) of the corrected fall output Plim in this example may be the same as or different from the change rate (slope a) of the corrected fall output Plim described in FIG.

  Then, when the corrected decrease output Plim decreases to the predicted minimum value (predetermined value) (time T5), arithmetic control is started to keep the target value of the system output Psys constant at the predicted minimum value (system target output Psys_c) (FIG. 6). (See the thick dotted line in the middle). Therefore, after time T <b> 5, the system output Psys having substantially the same value as the predicted minimum value is constantly output from the solar power generation system 100 to the power system 200.

  In the example illustrated in FIG. 6, the example in which the corrected decrease output Plim is decreased after time T4 has been described, but the present invention is not limited to this. Depending on the timing (time) at which the fluctuation of the generated power Ppv is predicted to increase, the system target output Psys at that time may be the same value as the predicted minimum value of the generated power Ppv. In this case, after the time when the fluctuation of the generated power Ppv is predicted to increase, control is performed so that the target value of the system output Psys is constant as the predicted minimum value (system target output Psys_c).

[Second Output Control Example of System Output Psys]
Next, a second output control example of the system output Psys by the overall controller 10 of this embodiment will be described with reference to FIG. FIG. 7 is a diagram illustrating a time change example of the target value of the system output Psys that is calculated and controlled by the overall controller 10 (system target output calculation unit 20).

  In the second output control example shown in FIG. 7, when it is predicted that the fluctuation of the generated power Ppv will increase, the average value of the generated power Ppv predicted in the time zone when the fluctuation of the generated power Ppv increases (hereinafter referred to as “prediction”). Is set as the final value of the corrected fall output Plim. In FIG. 7, the time when the fluctuation of the generated power Ppv is predicted to increase is the time T6, and the start time of the arithmetic control with the target value of the system output Psys being the final value (system target output Psys_c) is the time An example of T7 (> T6) is shown.

  In the example shown in FIG. 7, when it is predicted that the fluctuation of the generated power Ppv (see the solid line in FIG. 7) will increase at time T6, the calculation control of the target value of the system output Psys is the same as that in the first embodiment. Similarly, the calculation control of the corrected lowering output Plim is switched. At this time, a predicted average value is calculated based on a plurality of predicted output values Ppv_pre output from the power generation amount prediction unit 3 and obtained at predetermined sampling time intervals over a specific time, and the predicted average value is corrected and decreased. It is set as the final value (predetermined value) of the output Plim.

  Next, after it is predicted that the fluctuation of the generated power Ppv will increase (after time T6), the corrected decrease output Plim is reduced to the predicted average value (predetermined value) at a predetermined change rate (slope c) with time (FIG. 7). (See the thick dashed line in the middle). That is, also in the example illustrated in FIG. 7, at time T6, the overall controller 10 forcibly switches the output control of the system output Psys to the output control in which the system output Psys decreases with the change rate of the slope c with time. .

  Note that the change rate (slope c) of the corrected descending output Plim in this example can be set to an arbitrary change rate (slope) as long as it is within the allowable range defined by the constraint conditions. Further, the change rate (slope c) of the corrected fall output Plim in this example is the change rate (slope a) of the corrected fall output Plim described in FIG. 4 or the change rate (slope b) of the corrected fall output Plim described in FIG. ) May be the same or different.

  Then, when the corrected decrease output Plim decreases to the predicted average value (predetermined value) (time T7), arithmetic control is started to make the target value of the system output Psys constant (predicted average value (system target output Psys_c)) (FIG. 7). (See the thick dotted line in the middle). Therefore, after the time T7, the system output Psys having substantially the same value as the predicted average value is constantly output from the solar power generation system 100 to the power system 200.

  In the example illustrated in FIG. 7, the example in which the corrected decrease output Plim is decreased after time T4 has been described, but the present invention is not limited to this. Depending on the timing (time) at which the fluctuation of the generated power Ppv is predicted to increase, the system target output Psys at that time may be lower than the predicted average value of the generated power Ppv or may be the same value as the predicted average value. is there. In the former case, after the time when the fluctuation of the generated power Ppv is predicted to increase, control is performed to increase the corrected decrease output Plim to the predicted average value at a predetermined change rate. On the other hand, in the latter case, after the time when the fluctuation of the generated power Ppv is predicted to increase, control is performed so that the target value of the system output Psys is constant as the predicted average value (system target output Psys_c).

[System output target value correction processing example]
The basic procedure for correcting the target value of the system output Psys in this embodiment is the same as that in the first embodiment described with reference to the flowchart of FIG. However, the target value correction processing for the system output Psys in the present embodiment is different from that in the first embodiment in the following points.

  In this embodiment, the output prediction value Ppv_pre used when obtaining the data (predicted fluctuation amount ΔPpv_pre) necessary for the fluctuation prediction of the generated power Ppv in step S11 is a predetermined sampling time interval over a specific period after the current time. It becomes a plurality of predicted values obtained in the above. Further, the threshold value (predetermined value) of the corrected descending output Plim used in the determination process of step S15 is the predicted minimum value or the predicted average value of the generated power Ppv in the time zone when the fluctuation of the generated power Ppv becomes large.

[Effects]
In the first output control example in the present embodiment described above, the system output Psys is the predicted minimum value of the generated power Ppv after the corrected lowered output Plim is lowered to the predicted minimum value of the generated power Ppv (after time T5). Constant output. In this case, the operation of the storage battery system 2 after time T5 is a charging operation. Therefore, in the first output control example described above, the discharge operation of the storage battery system 2 decreases during the time period when the fluctuation of the generated power Ppv increases even if the fluctuation of the generated power Ppv increases. The progress of deterioration can be suppressed.

  In the second output control example in the present embodiment described above, the system output Psys is the predicted average value of the generated power Ppv after the corrected lowered output Plim is reduced to the predicted average value of the generated power Ppv (after time T7). At a constant output. In this case, in the output control of the system output Psys after time T7, since the charge amount and the discharge amount of the storage battery system 2 are substantially balanced, the progress of deterioration of the storage battery 8 can be suppressed.

  Furthermore, in this embodiment, both the power generation device unit 1 and the storage battery system 2 (the entire photovoltaic power generation system 100) are not stopped after the time when the fluctuation of the generated power Ppv is predicted to increase. In the present embodiment, output control is performed so that the fluctuation of the system output Psys falls within the allowable range even after the time when the fluctuation of the generated power Ppv is predicted to increase. That is, in this embodiment, even if the fluctuation of the generated power Ppv becomes large, the system output Psys is transferred to the power system 200 while suppressing the fluctuation of the system output Psys within an allowable range without stopping the photovoltaic power generation system 100. Can be output. Therefore, in the solar power generation system 100 of the present embodiment, even if the fluctuation of the generated power Ppv becomes large, it is possible to prevent the deviation of the fluctuation of the system output Psys from the allowable range and to secure the amount of power sales.

<Third Embodiment>
3rd Embodiment demonstrates another structure which does not stop a solar power generation system (a power generation device part and a storage battery system), when it is estimated that the fluctuation | variation of generated electric power Ppv becomes large. In addition, since the structure of the photovoltaic power generation system of this embodiment is the same as that of the said 1st Embodiment (refer FIGS. 1-3), here, the structure of the photovoltaic power generation system of this embodiment is demonstrated. Description is omitted. In the following, each component will be described with the same reference numerals as those in the first embodiment.

  In the photovoltaic power generation system 100 of the present embodiment, when it is predicted that the fluctuation of the generated power Ppv will be large, after that, mainly the operation of charging the generated power Ppv with the storage battery 8 is performed, and the system output Psys is the power system. No power is supplied to 200 (power sale is stopped). For example, in the output control of the system output Psys of the second embodiment (see, for example, FIGS. 6 and 7), the final value (Psys_c) of the corrected descending output Plim is set to zero. It can be realized by setting.

  Therefore, also in this embodiment, when it is predicted that the fluctuation of the generated power Ppv will increase, the system target output calculation unit 20 thereafter reduces the corrected decrease output Plim at a predetermined rate of change with time. Then, calculation control of the target value of the system output Psys is performed. Then, when the corrected lowering output Plim becomes zero, thereafter, arithmetic control for making the target value of the system output Psys (system target output Psys_c) constant at zero is performed.

  When such output control of the system output Psys is performed, the storage battery system 2 is excluded except for a slight time period in which the generated power Ppv is larger than the corrected lower output Plim after the time when the fluctuation of the generated power Ppv is predicted to increase. The operation is a charging operation. That is, in the present embodiment, the operation of the storage battery system 2 is substantially only the charging operation in the time zone after the time when the fluctuation of the generated power Ppv is predicted to be large (the time zone in which the fluctuation of the generated power Ppv is large). Therefore, the progress of deterioration of the storage battery 8 can be suppressed.

  In the present embodiment, the system output Psys is controlled while suppressing the fluctuation of the system output Psys within the allowable range during the period from when the fluctuation of the generated power Ppv is predicted to increase until the corrected decrease output Plim reaches zero. Reduce. In this period, power is supplied from the solar power generation system 100 to the power system 200. Therefore, in the present embodiment, as in the first embodiment, even if a situation in which the fluctuation of the generated power Ppv is large occurs, during this period, deviation from the allowable range of the system output Psys is prevented. Electricity sales can be secured.

<Fourth Embodiment>
In the various embodiments described above, the configuration in which the information (output predicted value Ppv_pre) used to determine whether or not the fluctuation of the generated power Ppv becomes large is obtained from the power generation amount prediction unit 3, but the present invention is based on this. It is not limited. Any information (data) that can determine whether or not the fluctuation of the generated power Ppv becomes large can be adopted, and the acquisition method is also arbitrary. In the fourth embodiment, a photovoltaic power generation system having a configuration that can determine whether or not the fluctuation of the generated power Ppv becomes large without providing the power generation amount prediction unit 3 will be described.

  FIG. 8 is a functional block diagram showing an internal configuration of the overall controller 10 and its peripheral configuration in the present embodiment. In FIG. 8, the same components as those in the first embodiment (see FIG. 2) are denoted by the same reference numerals.

  As is clear from a comparison between FIG. 8 and FIG. 2, the photovoltaic power generation system of the present embodiment is different from the power generation amount prediction unit 3 in the photovoltaic power generation system 100 of the first embodiment. (Change amount calculation unit) is provided. In the solar power generation system of the present embodiment, the configuration other than the provision of the differential calculation unit 30 instead of the power generation amount prediction unit 3 is the same as the corresponding configuration of the solar power generation system 100 of the first embodiment. It is the same. Therefore, only the configuration of the differential calculation unit 30 will be described here.

  The input end of the differential calculation unit 30 is connected to the sunlight PCS 5, and the output end is the other input end of the system target output calculation unit 20 (in the first embodiment, the input to which the output predicted value Ppv_pre is input). End). The differential calculation unit 30 calculates a differential value Ppv_dif (change amount) of the fluctuation of the generated power Ppv based on the generated power monitor signal Ppv_fb input from the PCS 5 for sunlight. Although not shown, in the present embodiment, the system target output calculation unit 20 has a function of storing a history of the differential value Ppv_dif.

  As the differential value Ppv_dif, for example, a value obtained by dividing the difference value between the generated power monitor signal Ppv_fb at the current time and the generated power monitor signal Ppv_fb one sampling time ago by the sampling time can be used. Further, as the differential value Ppv_dif, for example, a difference value between the generated power monitor signal Ppv_fb at the current time and the generated power monitor signal Ppv_fb one sampling time ago may be employed.

  In the present embodiment, the system target output calculator 20 determines whether or not the fluctuation of the generated power Ppv will increase in the future based on the differential value Ppv_dif of the fluctuation of the generated power Ppv input from the derivative calculator 30. judge. Specifically, the system target output calculation unit 20 continues (elapses) for a predetermined period of time when the differential value Ppv_dif of the fluctuation of the generated power Ppv is positive or negative based on the history of the differential value Ppv_dif. Then, it is determined that the fluctuation of the generated power Ppv becomes large. In addition, although the threshold value (value of predetermined time) used by this determination can be set arbitrarily, you may set based on the past rule of thumb etc., for example.

  Moreover, the determination method of the magnitude of the fluctuation | variation of the generated electric power Ppv in this embodiment is not limited to this example. For example, simply, if the differential value Ppv_dif is a value greater than or equal to a predetermined threshold value, it may be predicted that fluctuations in the generated power Ppv will increase.

  The basic procedure of the correction process of the target value of the system output Psys in this embodiment is the same as that of the various embodiments described with reference to the flowchart of FIG. However, the target value correction processing for the system output Psys in the present embodiment is different from that in the various embodiments described above.

  In the present embodiment, the differential value Ppv_dif of the fluctuation of the generated power Ppv is calculated as data necessary for the fluctuation prediction of the generated power Ppv in the process of step S11. Further, in the determination process of step S12, based on the history of the differential value Ppv_dif, it is determined whether or not the state where the differential value Ppv_dif of the fluctuation of the generated power Ppv is positive or negative continues for a predetermined time. The If the state in which the differential value Ppv_dif of the fluctuation of the generated power Ppv is positive or negative continues for a predetermined time, it is determined in step S12 that the fluctuation of the generated power Ppv will increase in the future. .

  In the above-described solar power generation system of the present embodiment, the data acquisition method necessary for predicting the fluctuation of the generated power Ppv and the determination process for determining whether or not the fluctuation of the generated power Ppv is large are different from those of the above-described various embodiments. However, the output control method of the system output Psys of this embodiment (the method of correcting the target value of the system output Psys) is the same as that of the above-described various embodiments. Therefore, in this embodiment, the same effect as the above-described various embodiments can be obtained. Furthermore, in the photovoltaic power generation system according to the present embodiment, the expensive power generation amount prediction unit 3 is not necessary, so that the cost of the photovoltaic power generation system can be reduced. From the viewpoint of prediction accuracy, the configuration including the power generation amount prediction unit 3 is superior to the configuration of the present embodiment.

  In the configuration example shown in FIG. 8, the configuration example in which the generated power monitor signal Ppv_fb for calculating the differential value Ppv_dif of the fluctuation of the generated power Ppv is measured by the solar PCS 5 is described. It is not limited. For example, a power meter that measures DC generated power output from the solar panel 4 may be provided separately, and the measurement result of the power meter may be used as the generated power monitor signal Ppv_fb.

<Various modifications>
As described above, the power generation system according to various embodiments of the present invention has been described. However, the present invention is not limited to these, and various other types are possible without departing from the gist of the present invention described in the claims. Variations and application examples can be taken.

[Modification 1]
In the various embodiments described above, the configuration in which one power control device 7 is provided for one power generation device unit 1 (solar panel 4 and solar PCS 5) is described, but the present invention is not limited to this. For example, in a solar power generation system provided with a plurality of power generation device units, a configuration may be adopted in which one power control device 7 is provided for a plurality of power generation device units.

  In this case, a plurality of power generation units are connected to one power control unit 7, and the power control unit 7 performs output control of the system output Psys based on the generated power monitor signal Ppv_fb input from each power generation unit. . In such a configuration, the same effects as those of the above-described various embodiments can be obtained, and even if the generated power Ppv and the variation amount thereof vary greatly between the power generation units, they can be compensated for and more stable. The system output Psys can be supplied to the power system.

  Moreover, although the said various embodiment demonstrated the structure which provides one PCS5 for sunlight and PCS9 for storage batteries in the solar power generation system 100, this invention is not limited to this. For example, in a large-scale photovoltaic power generation system such as a mega solar system equipped with a large number of solar panels, a plurality of solar PCSs are installed according to a plurality of solar panels, and a plurality of solar batteries are accommodated corresponding to a plurality of storage batteries. In some cases, a storage battery PCS is installed. The technology of the present invention described above can also be applied to a solar power generation system in which such a plurality of solar PCSs and a plurality of storage battery PCSs are installed, and similar effects can be obtained.

  In this case, a plurality of solar PCSs and a plurality of storage battery PCSs are connected to one power control device 7 (overall controller 10). Then, the overall controller 10 performs a smoothing process on each generated power monitor signal Ppv_fb input from each sunlight PCS. Next, the overall controller 10 calculates the total value of the smoothed generated power monitor signals Ppv_fb as the system target output Psys. Next, the overall controller 10 calculates the charge / discharge target value Pbt based on the calculated system target output Psyst. In this case, the calculated charge / discharge target value Pbt is a total value of the charge / discharge target values output to each of the plurality of storage battery PCSs.

  Next, the overall controller 10 determines the charge / discharge target value to be distributed to each storage battery PCS based on the charge / discharge target value Pbt, the power generation status of each solar PCS, the charge state (SOC signal) of each storage battery, and the like. decide. Then, the overall controller 10 outputs a corresponding charge / discharge target value to each storage battery PCS, and performs output control of the system output Psys. At this time, all of the charge / discharge target values distributed to the storage battery PCSs may be set to the same value.

[Modification 2]
In the output control method of the system output Psys in the various embodiments described above, the example in which the correction control of the target value of the system output Psys described above is started when the fluctuation of the generated power Ppv is predicted to be large has been described. Is not limited to this.

  For example, when the fluctuation of the generated power Ppv is continuously monitored for a predetermined time after the fluctuation of the generated power Ppv is predicted to increase, and the fluctuation of the generated power Ppv does not fall within the predetermined time, the system output Psys described above is used. The target value correction control may be started. Further, for example, a prediction determination is made as to whether or not the fluctuation of the generated power Ppv is increased again after a predetermined time has elapsed since the fluctuation of the generated power Ppv is predicted to increase. At this time, when the fluctuation is predicted to increase, the above-described correction control of the target value of the system output Psys may be started.

  In the configuration of this example, the execution frequency of the target value correction control of the system output Psys in the various embodiments described above is reduced. In this case, it is possible to reduce the execution frequency of the stop operation of the solar power generation system, the power sale stop operation and / or the system output Psys descending operation, and a stable power supply operation (power sale operation) becomes possible.

[Modification 3]
In the first to third embodiments, the configuration in which the output control method for the system output Psys of each embodiment is executed alone has been described. However, the present invention is not limited to this. In the first to third embodiments, the configuration of the power control device 7 is the same regardless of the type of the output control method of the system output Psys. Therefore, the above-described photovoltaic power generation system 100 may be a system that can execute the output control method for all the system outputs Psys of the first to third embodiments.

  In this case, according to the power generation status of the power generation device unit 1 (for example, the fluctuation amount of the generated power Ppv), the state of charge of the storage battery 8 (SOC signal), and the like, a predetermined value is selected from the first to third embodiments. It becomes possible to select the output control method of the system output Psys of the embodiment.

  For example, the output control method of the second embodiment may be selected in a time zone in which a major trouble occurs when the supply of the system output Psys is stopped. Also, for example, when it is predicted that the fluctuation of the generated power Ppv will increase, based on the SOC signal, if it is determined that sufficient storage capacity remains in the storage battery 8, the third embodiment will be described. An output control method may be selected.

  Moreover, in the photovoltaic power generation system 100 that can execute the output control methods of all the system outputs Psys of the first to third embodiments, it is also possible to apply a combination of the output control methods of a plurality of types of system outputs Psys. become. For example, after the fluctuation of the generated power Ppv is predicted to increase, first, the output control of the system output Psys is performed using the output control method of the second embodiment. However, when it becomes difficult to suppress the fluctuation of the system output Psys within the allowable range by this method, the output control method of the system output Psys is changed from the method of the second embodiment to the first embodiment. Switch to the method.

  As described above, in the solar power generation system 100 of this example, not only the same effects as those of the first to third embodiments can be obtained, but also it is possible to respond flexibly to every situation. . Note that the output control method of the system output Psys in this example can be applied to the fourth solar power generation system, and the same effect can be obtained.

[Other variations]
In the various embodiments and the various modifications described above, the configuration of the photovoltaic power generation system has been described in detail and specifically in order to explain the present invention in an easy-to-understand manner. However, the present invention does not necessarily include all the configurations described. It is not limited.

  In addition, each configuration, function, processing unit, and the like related to the signal control (electrical signal processing control) may be realized by hardware by designing a part or all of them with, for example, an integrated circuit. At this time, some or all of the components, functions, processing units, and the like related to the signal control may be integrated as appropriate.

  Furthermore, each configuration, function, processing unit, and the like related to the signal control may be realized by a processor interpreting and executing a program that realizes each function. That is, each configuration, function, processing unit, and the like related to the signal control may be realized by software. Information (data) such as programs, tables, and files for realizing each function can be stored not only in the above-described built-in memory unit but also in a recording device such as a hard disk or an SSD (Solid State Drive). . Information (data) such as programs, tables, and files for realizing each function can also be stored in a recording medium such as an IC (Integrated Circuit) card, an SD (Secure Digital) card, a DVD (Digital Versatile Disc), or the like. .

[Application example]
The above-described storage battery system 2 to which the technology of the present invention is applied can be applied to a solar power generation apparatus (solar panel and solar PCS) having an arbitrary configuration regardless of existing or new installation. Moreover, the power control apparatus 7 to which the above-described technology of the present invention is applied can be applied to any power generation facility having a solar panel, a solar PCS, a storage battery, and a storage battery PCS, regardless of whether the power control apparatus 7 is existing or newly installed. it can. In these cases, for example, it is possible to easily construct a photovoltaic power generation system that can obtain the same effects as the photovoltaic power generation systems of the various embodiments described above.

  Further, in the various embodiments and the various modifications described above, the solar power generation system provided with the storage battery system is described as an example of the power generation system to which the technology of the present invention is applied, but the present invention is not limited to this. The present invention is applicable to any power generation system as long as it is a power generation system provided with a storage battery system. In particular, the technology of the present invention is suitable for a power generation system in which an event in which fluctuation of generated power becomes large due to external factors such as weather may frequently occur. Is preferred.

  DESCRIPTION OF SYMBOLS 1 ... Power generation device part, 2 ... Storage battery system, 3 ... Power generation amount prediction part, 4 ... Solar power panel, 5 ... PCS for sunlight, 6 ... Storage battery device, 7 ... Power control device, 8 ... Storage battery, 9 ... For storage battery PCS, 10 ... overall controller, 11 ... network, 12 ... external controller, 13 ... terminal, 20 ... system target output calculation unit, 21 ... difference calculation unit, 22 ... smoothing processing unit, 23 ... target value correction unit, 24 ... restriction Condition storage unit 25 ... Fluctuation scale determination unit 26 ... Correction amount calculation unit 30 ... Differential calculation unit 100 ... Solar power generation system 200 ... Electric power system

Claims (11)

A power generator,
A storage battery device that has a storage battery and suppresses fluctuations in system output power that is the sum of the generated power output from the power generation device and the charge / discharge power of the storage battery;
A determination unit that determines whether or not the variation in the generated power increases; and when the determination unit determines that the variation in the generated power increases, the time period during which the variation in the generated power increases A power generation system comprising: a power generation device and an output control device that stops operation of the storage battery device. The output control device performs control to reduce the system output power to zero at a change rate within an allowable range during a time period when the fluctuation of the generated power becomes large, and a predetermined timing during the control period. The power generation system according to claim 1, wherein the operation of the power generation device is stopped and the operation of the storage battery device is stopped at the end of the control. The power generation system according to claim 1, wherein the determination unit determines whether or not the variation in the generated power becomes large based on information on the prediction of the variation in the generated power. Furthermore, a change amount calculation unit that sequentially calculates a change amount of the generated power is provided,
The determination unit, based on the calculation result of the change amount calculation unit, when the state of the change amount of the generated power is a positive value or a negative value continues for a predetermined time, The power generation system according to claim 1, wherein it is determined that fluctuations in generated power increase. 2. The power generation according to claim 1, wherein the output control device starts a stop operation of the power generation device and the storage battery device after a predetermined time has elapsed after the determination unit determines that the fluctuation of the generated power increases. system. A power generator,
A storage battery device that has a storage battery and suppresses fluctuations in system output power that is the sum of the generated power output from the power generation device and the charge / discharge power of the storage battery;
A determination unit that determines whether or not the variation in the generated power increases; and when the determination unit determines that the variation in the generated power increases, the time period during which the variation in the generated power increases A power generation system comprising: an output control device that controls operation of the power generation device and the storage battery device so that system output power is output at a predetermined value. The output control device performs control to change the system output power to the predetermined value at a change rate within an allowable range in a time zone in which the fluctuation of the generated power becomes large, and then the system output power is The power generation system according to claim 6, wherein operation control of the power generation device and the storage battery device is performed so that the power is output at a predetermined value constant. The power generation system according to claim 6, wherein the predetermined value is a minimum value of the generated power in a time period in which fluctuations in the generated power become large. The power generation system according to claim 6, wherein the predetermined value is an average value of the generated power during a time period in which the fluctuation of the generated power becomes large. A power generator,
A storage battery device that has a storage battery and suppresses fluctuations in system output power that is the sum of the generated power output from the power generation device and the charge / discharge power of the storage battery;
A determination unit that determines whether or not the variation in the generated power increases; and when the determination unit determines that the variation in the generated power increases, the time period during which the variation in the generated power increases A power generation system comprising: an output control device that performs operation control of the power generation device and the storage battery device so that all of the generated power generated by the power generation device is charged by the storage battery device. The output control device performs control to reduce the system output power to zero at a change rate within an allowable range in a time zone when the fluctuation of the generated power becomes large, and then the power generated by the power generation device. The power generation system according to claim 10, wherein operation control of the power generation device and the storage battery device is performed so that all of the generated power is charged by the storage battery device.

Images