JP6768571B2 - Power controller, method and power generation system - Google Patents

Description

The present invention relates to a technique for suppressing fluctuations in electric power output from a power generation device having a power generation device and a power storage device using renewable energy.

In recent years, the introduction of renewable energy power generation systems such as solar power generation and wind power generation has been promoted in consideration of environmental problems. Due to the nature of renewable energy power generation systems, the output power fluctuates greatly. Therefore, it may cause voltage fluctuations and frequency fluctuations in the power system connected to the renewable energy power generation system. On the other hand, for example, in Patent Document 1, as a countermeasure, the renewable energy power generation system is provided with a power storage device, and the fluctuation of the output power from the renewable energy power generation system is smoothed by charging and discharging the power storage device. The technology is described.

WO2016 / 0633555

By the way, the power storage device has preferable usage conditions regarding temperature, charge / discharge power, charge rate (SOC), and the like. If charging and discharging are repeated beyond the range of these usage conditions, the power storage device deteriorates.

On the other hand, when the power storage device is allowed to operate only within the range of preferable usage conditions, it cannot follow the charge / discharge command even if the charge / discharge command exceeds the range. Therefore, the combined output (system output) of the power generation output of renewable energy and the charge / discharge output from the power storage device may exceed the permissible range of output fluctuation of the power system.

Therefore, an object of the present invention is to provide a power control technique for suppressing fluctuations in the output to the power system within an allowable range while suppressing deterioration of the power storage device.

In order to solve such a problem, the power control device according to one embodiment of the present invention is a power control device that controls power output from a power generation device having a power generation device using renewable energy and a power storage device. The target output calculation unit that smoothes the monitor value of the generated power of the power generation device to generate the first output target value, the generated output power that is the output from the power generation device, and the charge / discharge from the power storage device. The first charge / discharge power target value, which is the difference between the first output target value and the monitor value, is stored in the storage so that the temporal fluctuation of the combined output power combined with the power is suppressed within a predetermined range. a charge-discharge electric power correcting unit for correcting the second charge-discharge power target value based on the allowable discharge electric power of the temperature or the electrical storage device of the device, was closed, the charge-discharge electric power correcting unit, the first charge-discharge electric power When the target value is not within the allowable charge / discharge power range and the temperature of the power generation device is equal to or lower than the predetermined temperature, the same value as the first charge / discharge power target value is set as the second charge / discharge power target value. And . Then, the charge / discharge power of the power storage device is controlled based on the second charge / discharge power target value.

Overall view of the renewable energy power generation system. Block diagram of the central controller. The block diagram which shows the detail of an output correction part. Explanatory drawing of SOC correction calculation part. The flowchart which shows the arithmetic processing of the SOC correction arithmetic unit. Explanatory drawing of the allowable power correction calculation part. A flowchart showing a process of correcting an output based on an allowable power and a temperature. A flowchart showing a process of correcting the output based on the temperature. The whole view of the renewable energy power generation system in Embodiment 2. The block diagram of the control controller of Embodiment 2. The explanatory view which shows the output correction method of Embodiment 2. A flowchart showing a process of correcting an output based on an allowable power. A flowchart showing a process of correcting the output based on the temperature. The whole view of the renewable energy power generation system in Embodiment 3. The block diagram of the control controller of Embodiment 3. The explanatory view which shows the output correction method of Embodiment 3. The whole view of the renewable energy power generation system in Embodiment 4. The block diagram of the control controller of Embodiment 4. The explanatory view which shows the method of creating the power generation amount prediction waveform of Embodiment 4.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings for explaining the present invention, those having the same function may be designated by the same reference numerals, and the repeated description thereof may be omitted.

In the present embodiment, the solar power generation system will be described as an example of the renewable energy power generation device, but the present embodiment is not limited to this and can be applied to a wind power generation device and the like. It is also possible to add a photovoltaic power generation system to a system such as a water electrolyzer or a hydrogen generator.

[Embodiment 1]
FIG. 1 is a block diagram showing an overall configuration of a renewable energy power generation system 100 according to a first embodiment of the present invention.

The renewable energy power generation system (hereinafter, sometimes simply referred to as “power generation system”) 100 is connected to the power system 200. The power generation system 100 includes a photovoltaic power generation device (hereinafter, may be simply referred to as a “power generation device”) 1, a power storage device 2, and a power control device 3. The power generation device 1 and the power storage device 2 are electrically connected to the power system 200 via the connection point cp, and the power generation output power Ppv output from the power generation device 1 and the charge / discharge power input / output from the power storage device 2 The combined output power, which is the sum of the PBatts, is supplied to the power system 200 as the system output Psys of the solar power generation system 100. The power generation output power Ppv of the power generation device 1 is smoothed by the charge / discharge operation of the power storage device 2.

The power generation device 1 has a solar panel 4 and a solar power conditioner 5 (hereinafter, referred to as “solar PCS5”). The solar panel 4 can be configured by connecting a plurality of silicon-based solar cells such as a single crystal silicon type, a polycrystalline silicon type, a microcrystal silicon type, and an amorphous silicon type in series and parallel. Further, the solar panel 4 may be configured by connecting a plurality of compound solar cells such as InGaAs, GaAs, and CIS (calcovalite) in series and parallel. Further, in the present embodiment, as the solar cell constituting the solar panel 4, for example, an organic solar cell such as a dye-sensitized solar cell or an organic thin film solar cell may be used. Further, the photovoltaic PCS5 converts the DC power generated from the solar panel 4 into AC and outputs it to the power system 200 as the power output power Ppv. Therefore, the generated output power Ppv supplied to the power system 200 is limited by the rated output of the photovoltaic PCS5. Here, in the present embodiment, the solar power generation device using the solar panel 4 is described as an example, but a wind power generation device in which the solar panel 4 is replaced with a wind turbine may be used.

The power storage device 2 is composed of a storage battery power conditioner 6 (hereinafter, referred to as “storage battery PCS 6”) and a storage battery 7. The DC charge / discharge power output from the storage battery 7 is converted into alternating current by the storage battery PCS6, and is output to the power system 200 as the charge / discharge power PBatt. The storage battery PCS6 and the above-mentioned solar PCS5 may be referred to as a grid interconnection inverter. The storage battery 7 is composed of a secondary battery such as a lead storage battery, a lithium ion storage battery, and a nickel / hydrogen storage battery.

The power control device 3 has a function for suppressing fluctuations in the system output of the power generation system 100. The power control device 3 includes, for example, a central controller 8, a communication network 9 (Internet, etc.), an external controller 10, and a terminal 11. In the power control device 3, the control controller 8 is communicably connected to the external controller 10 via the communication network 9, and the external controller 10 is connected to the terminal 11 via a serial bus, a parallel bus, or the like.

In the power control device 3 having such a configuration, the operator can control the processing operation of the control controller 8 via the external controller 10 installed at a place away from the power generation system 100. For example, when the operator operates the terminal 11, the control controller 8 can be accessed via the external controller 10 and various setting values required for various controls can be input. Further, for example, the operator can display the state (operating status) of the power generation system 100 on the terminal 11. In the present embodiment, a configuration example in which the power control device 3 includes the external controller 10, the communication network 9, and the terminal 11 will be described, but the present invention is not limited to this, and these configurations are the power control device 3. It may be provided externally.

The control controller 8 is composed of, for example, a computer having a CPU (Central Processing Unit), a memory, and the like. The control controller 8 is connected to the solar PCS5, the storage battery PCS6, and the storage battery 7 via a communication network. In this case, the communication connection mode can be set arbitrarily, and for example, any mode of wireless communication and wired communication can be applied. Although the details will be described later, the control controller 8 acquires a monitor signal of the power generation output power Ppv measured by the photovoltaic PCS 5 (hereinafter, referred to as “power generation output monitor signal Ppv_fb”). The power generation output monitor signal Ppv_fb may be measured by a power meter or the like provided separately from the solar PCS5. Further, the control controller 8 acquires a signal including information on the charging state (hereinafter, referred to as “SOC (State Of Charge) signal”), a battery temperature T, and an allowable power Poll from the storage battery 7. Here, the permissible power Poll is composed of an permissible charge power and an permissible discharge power, and is not a constant value but varies according to the SOC. The operation of acquiring these various signals (various information) by the control controller 8 may be performed periodically or irregularly. Further, the control controller 8 performs various calculations for suppressing (compensating) the power fluctuation based on the power generation output monitor signal Ppv_fb input from the solar PCS5. For example, the control controller 8 calculates the system output target value Psys ^*, which is a guideline for suppressing fluctuations, based on the input power generation output monitor signal Ppv_fb. Further, the control controller 8 obtains the final charge / discharge target value PBatt ^* based on the system output target value Psys ^* , and outputs a control command to the storage battery PCS6. The storage battery PCS6 (power storage device 2) adjusts (controls) the charge / discharge power PBatt for the power system 200 based on the final charge / discharge target value PBatt ^* included in the control command of the control controller 8. For example, the storage battery PCS6 (power storage device 2) is controlled so that the charge / discharge power PBatt becomes the same value as the final charge / discharge target value PBatt ^* . As a result, the system output Psys is controlled to be the same value as the system output target value Psys ^* . The internal configuration of the control controller 8 for executing these operations will be described in detail later.

FIG. 1 shows a case where the solar PCS5 and the storage battery PCS6 are installed independently, but the present invention is not limited to this. For example, in a large-scale photovoltaic power generation system 100 such as a mega solar equipped with a large number of solar panels 4, a plurality of solar PCS 5s are installed according to the plurality of solar panels 4, and a plurality of storage batteries 7 are supported. Then, a plurality of PCS6s for storage batteries may be installed. In this case, the control controller 8 may calculate the system output target value Psys ^* as the total value of a plurality of solar power PCS5s. Similarly, the control controller 8 may calculate the final charge / discharge target value PBatt ^* as the total value of a plurality of power storage PCS6s.

Further, the power generation system 100 of the present embodiment can be easily configured by connecting the power storage device 2 to the existing or new power generation device (solar panel 4 and PCS5 for solar power) 1. Further, the power generation system 100 of the present embodiment can be easily configured by connecting the power control device 3 to the equipment having the existing solar panel 4, storage battery 7, solar PCS5, and storage battery PCS6. ..

FIG. 2 is a block diagram of the control controller 8.

The control controller 8 has a system target value calculation unit 81, an output correction unit 82, and a fluctuation rate correction unit 83.

The system target value calculation unit 81 calculates the system output target value Psys ^* based on the power generation output monitor signal Ppv_fb input from the photovoltaic PCS 5 of the power generation device 1. The system output target value Psys ^* is a target value of the system output power output to the power system 200. The system target value calculation unit 81 has a smoothing unit 811. The smoothing unit 811 smoothes the monitor value of the generated power based on the power generation output monitor signal Ppv_fb to obtain the system output target value Psys ^* . As the smoothing operation, a moving average method, a low-pass filter operation such as a temporary delay, or the like can be used.

The output correction unit 82 contains an initial charge / discharge target value PBatt ^*** , which is the difference between the system output target value Psys ^* and the power generation output monitor signal Ppv_fb, a system output target value Psys ^* , the SOC of the storage battery 7, and the temperature T. And the permissible power Pollow are input. The output correction unit 82 sets the initial charge / discharge target value PBatt ^*** to the SOC, temperature T, or allowable charge / discharge power of the storage battery 7 so that the temporal fluctuation of the system output Psys is suppressed within a predetermined range. Based on this, the intermediate charge / discharge target value PBatt ^** is corrected. Details of the processing of the output correction unit 82 will be described later.

The calculated intermediate charge / discharge target value PBatt ^** is input to the fluctuation rate correction unit 83. The fluctuation rate correction unit 83 corrects the intermediate charge / discharge target value PBatt ^** so that the fluctuation of the system output Psys falls within the predetermined fluctuation range required by the power system 200, and sets the final charge / discharge target value PBatt ^* . .. The final charge / discharge target value PBatt ^* is input to the storage battery PCS6.

The power generation system 100 must supply electric power to the electric power system 200 within the range of fluctuation (for example, the upper limit of the fluctuation rate n%) agreed with the transmission / distribution electric power company that manages the electric power system 200. It doesn't become. For example, within the jurisdiction of Hokkaido Electric Power Company, there is a requirement that the fluctuation of Psys for one minute is 1% or less of the specified power generation output.

FIG. 3 is a block diagram shown by the output correction unit 82.

The output correction unit 82 includes an SOC determination unit 821, a temperature determination unit 822, an allowable power determination unit 823, a switching unit 824, a switch 825, an SOC correction calculation unit 826, a temperature correction calculation unit 827, and an allowable power correction calculation unit 828.

Here, in the storage battery 7, in order to suppress its deterioration and extend its life, a range of recommended values for a predetermined parameter is defined as an allowable range. In the present embodiment, an allowable range consisting of an upper limit value and a lower limit value of the SOC and / or both of the SOC and the temperature of the storage battery 7 may be predetermined. The allowable range of the charge / discharge power of the storage battery 7 is determined by the allowable power Pollow that fluctuates according to the SOC. The allowable power Plow is composed of an upper limit value of the allowable charge power and an upper limit value of the allowable discharge power. In the present embodiment, the output correction unit 82 controls the storage battery 7 to operate within this permissible range in terms of SOC, temperature, and charge / discharge power, as described below.

For example, the output correction unit 82 acquires the current SOC, temperature T, and allowable power Poll from the storage battery 7. Then, the SOC determination unit 821 determines whether or not the current SOC is within the above-mentioned allowable range. The temperature determination unit 822 determines whether or not the current temperature T is within the above-mentioned allowable range. The permissible power determination unit 823 determines whether or not the intermediate charge / discharge target value PBatt ^** is within the permissible power Pollow range.

The determination results of the SOC determination unit 821, the temperature determination unit 822, and the allowable power determination unit 823 are input to the switching unit 824. Based on these determination results, the switching unit 824 outputs a switching signal indicating any one of SOC, temperature, and charge / discharge power to the switch 825. When any one of the parameters of SOC, temperature, and charge / discharge power exceeds the permissible range, the switching unit 824 outputs a switching signal for specifying the parameter exceeding the permissible range to the switch 825. When two or more parameters of SOC, temperature and charge / discharge power exceed the permissible range, the switching unit 824 identifies one of the parameters exceeding the permissible range according to a predetermined priority. Is output to the switch 825. For example, charge / discharge power may be the first priority. Alternatively, SOC or temperature may be the first priority.

The SOC correction calculation unit 826 corrects the initial charge / discharge target value PBatt ^*** based on the SOC of the storage battery 7. For example, the SOC correction calculation unit 826 performs a correction calculation of the initial charge / discharge target value PBatt ^*** so that the SOC of the storage battery 7 does not deviate from the above-mentioned allowable range and the fluctuation of the system output Psys is within a predetermined range. To do. The detailed processing of the SOC correction calculation unit 826 will be described later.

The temperature correction calculation unit 827 corrects the initial charge / discharge target value PBatt ^*** based on the temperature of the storage battery 7. For example, the temperature correction calculation unit 827 performs a correction calculation of the initial charge / discharge target value PBatt ^*** so that the temperature of the storage battery 7 does not deviate from the above-mentioned allowable range and the fluctuation of the system output Psys falls within a predetermined range. To do. The detailed processing of the temperature correction calculation unit 827 will be described later.

The permissible power correction calculation unit 828 corrects the initial charge / discharge target value PBatt ^*** based on the permissible power of the storage battery 7. For example, the allowable power correction calculation unit 828 corrects the initial charge / discharge target value PBatt ^*** so that the charge / discharge power of the storage battery 7 does not deviate from the allowable power Plow and the fluctuation of the system output Psys falls within a predetermined range. Perform the calculation. The detailed processing of the allowable power correction calculation unit 828 will be described later.

The switch 825 determines the intermediate charge / discharge target value PBatt ^** based on the calculation result of any one of the SOC correction calculation unit 826, the temperature correction calculation unit 827, and the allowable power correction calculation unit 828. For example, the switch 825 selects any one of the three correction modes of SOC correction, temperature correction, and allowable power correction, which corresponds to the parameter indicated by the switching signal of the switching unit 824. When the switch 825 selects the SOC correction mode, the calculation result of the SOC correction calculation unit 826 is output as the intermediate charge / discharge target value PBatt ^** . When the switch 825 selects the temperature correction mode, the calculation result of the temperature correction calculation unit 827 is output as the intermediate charge / discharge target value PBatt ^** . When the switch 825 selects the charge / discharge power correction mode, the calculation result of the allowable power correction calculation unit 828 is output as the intermediate charge / discharge target value PBatt ^** .

As a result, the fluctuation of the system output Psys is within a predetermined range, so that the fluctuation suppression performance can be maintained. Further, since charging / discharging is not performed beyond the range allowed by the storage battery 7, deterioration of the storage battery 7 can be suppressed.

If the output correction unit 82 does not need to correct the initial charge / discharge target value PBatt ^*** , the output correction unit 82 outputs the initial charge / discharge target value PBatt ^*** as the intermediate charge / discharge target value PBatt ^** without making the correction. ..

FIG. 4 is an explanatory diagram of an example of processing by the SOC correction calculation unit 826.

The upper part of the figure shows the time change of SOC. The lower part of the figure shows the time change of the system output target value Psys ^* . The SOC correction calculation unit 826 monitors the SOC. Then, as shown in the figure, when the SOC reaches the lower limit value (X%) of the allowable range at time t1, the SOC correction calculation unit 826 corrects the system output target value Psys ^* so as to reduce the reduction correction output Plim_d. calculate. Correspondingly, the initial charge / discharge target value PBatt ^*** is corrected, and the intermediate charge / discharge target value PBatt ^** is determined so that the charging power increases. When the switch 825 is in the SOC correction mode, this intermediate charge / discharge target value PBatt ^** is output, which reduces the system output Psys, so that the discharge power decreases (or the charging power increases) by that amount, and the SOC Will increase. Then, as shown in the figure, when the SOC reaches a predetermined threshold value (Y%) at time t2, the SOC correction calculation unit 826 calculates an increase correction output Plim_u that increases the system output Psys. As a result, the system output Psys increases and approaches the system output target value Psys ^* .

This makes it possible for the SOC to prevent deviations from the permissible range.

Here, the reduction correction output Plim_d is a straight line or a curve having a slope a1 (first angle) within an allowable range of fluctuation of the system output Psys. The increase correction output Plim_u is a straight line or a curve having a slope a2 (second angle) within an allowable range of fluctuation of the system output Psys. Here, a2 = −a1 may be used.

FIG. 5 is a flowchart illustrating the arithmetic processing of the SOC correction arithmetic unit 826.

When the SOC correction calculation unit 826 monitors the SOC and SOC <X% is detected (step 10: Yes), the SOC correction calculation unit 826 calculates the change rate a1 of the reduction correction output Plim_d (step 11). The SOC correction calculation unit 826 calculates the reduction correction output Plim_d using this change rate a1, and sets the intermediate charge / discharge target value PBatt ^** so that the system output switches from the system output target value Psys ^* to the reduction correction output Plim_d. Calculate (step 12).

When the SOC correction calculation unit 826 monitors the SOC and SOC> Y% is detected (step 13: Yes), the SOC correction calculation unit 826 calculates the change rate a2 of the increase correction output Plim_u (step 14). The SOC correction calculation unit 826 calculates the increase correction output Plim_u using this change rate a2, and sets the intermediate charge / discharge target value PBatt ^** so that the system output switches from the system output target value Psys ^* to the increase correction output Plim_u. Calculate (step 15).

The SOC correction calculation unit 826 determines whether or not the increase correction output Plim_u and the system output target value Psys ^* intersect (step 16). If they intersect (step 16: Yes), the increase correction output Plim_u is switched to the system output target value Psys ^* , and the normal mode is returned (step 17).

Here, the same control is possible even when the SOC reaches the upper limit. For example, when the SOC reaches a predetermined upper limit value, the SOC correction calculation unit 826 switches the system output target value Psys ^* to the increase correction output Plim_u. After that, when the SOC decreases and becomes smaller than the predetermined value, the target value of the system output is switched to the decrease correction output Plim_d. By switching the output, the charge amount of the storage battery is reduced, so that deviation from the usable range of the SOC can be prevented.

FIG. 6 is an explanatory diagram of an example of processing by the allowable power correction calculation unit 828. In the above example, the intermediate charge / discharge target value PBatt ^** is calculated so that the SOC does not deviate from the allowable range and the fluctuation of the system output also falls within the allowable range. However, the allowable power correction calculation unit 828 described below Calculates the intermediate charge / discharge target value PBatt ^** so that the charge / discharge power does not deviate from the allowable power Pollow range and the fluctuation of the system output also falls within the allowable range in the same manner as described above.

The upper part of the figure shows the time change of charge / discharge power (charge is indicated by plus and discharge is indicated by minus). The lower part of the figure shows the time change of the system output. As shown in the figure, when the charging power approaches or exceeds the permissible charging power at time t3, the permissible power correction calculation unit 828 determines that the intermediate charge / discharge target value PBatt ^** is within the permissible charge / discharge power Pollow. and the system based on the intermediate discharge target value Pbatt ^** output to increase or decrease at a first angle, defining the intermediate discharge target value Pbatt ^**. For example, the allowable power correction calculation unit 828 calculates the increase correction output Plim_u so that the system output increases from the system output target value Psys ^* , similarly to the SOC correction calculation unit 826. In response to this, the allowable power correction calculation unit 828 corrects the initial charge / discharge target value PBatt ^*** to the intermediate charge / discharge target value PBatt ^** . When the switch 825 is in the allowable power correction mode, this charging power intermediate charge / discharge target value PBatt ^** is adopted, which increases the system output and thus reduces the charging power by that amount.

When the intermediate charge / discharge target value PBatt ^** reaches a predetermined value, the allowable power correction calculation unit 828 determines the intermediate charge / discharge target value so that the system output based on the intermediate charge / discharge target value PBatt ^** decreases or increases at the second angle. Establish PBatt ^** . For example, in the allowable power correction calculation unit 828, when the intermediate charge / discharge target value PBatt ^** reaches a predetermined threshold value at time t4, the allowable power correction calculation unit 828 is the same as the SOC correction calculation unit 826. In addition, the decrease correction output Plim_d that is corrected so as to decrease the system output increased by the increase correction output Plim_u is calculated. As a result, the system output decreases and approaches the system output target value Psys ^* again.

Here, the same control is possible even when the discharge power approaches or exceeds the allowable discharge power. For example, when the discharge power approaches or exceeds the allowable discharge power, the allowable power correction calculation unit 828 switches the system output target value Psys ^* to the reduction correction output Plim_d. After that, when the intermediate charge / discharge target value PBatt ^** reaches a predetermined threshold value, the allowable power correction calculation unit 828 calculates the increase correction output Plim_u that is corrected so as to increase the reduced system output by the decrease correction output Plim_d. As a result, the system output increases and approaches the system output target value Psys ^* again.

As a result, it is possible to prevent the charge / discharge power from deviating from the permissible range.

Here, the increase correction output Plim_u is a straight line or a curve having a slope b1 (first angle) within a predetermined range of fluctuations in the system output Psys. The reduction correction output Plim_d is a straight line or a curve having a slope b2 (second angle) within a predetermined range of fluctuations in the system output Psys. Here, b2 = −b1 may be used.

FIG. 7 is a flowchart showing an example of another processing procedure of the allowable power correction calculation unit 828.

The permissible power correction calculation unit 828 determines whether the initial charge / discharge target value PBatt ^*** exceeds the permissible power Pollow range (step S20). Here, when the initial charge / discharge target value PBatt ^*** exceeds the allowable power Pollow range (step S20: Yes), the allowable power correction calculation unit 828 determines whether the temperature T of the storage battery 7 is equal to or lower than the predetermined temperature. Determine (step S21). When the temperature T of the storage battery 7 is equal to or lower than a predetermined temperature (step S21: Yes), the permissible power correction calculation unit 828 temporarily permits charge / discharge power exceeding the upper limit value of the permissible power Poll (step 22).

When the battery temperature T of the storage battery 7 is not high, even if the storage battery 7 is charged and discharged at a high output exceeding the allowable power Pallow for a short time, the effect is not large. By utilizing this property and temporarily allowing charge / discharge that exceeds the upper limit of the allowable power Pollow, fluctuations in the system output Psys can be suppressed within a predetermined range.

FIG. 8 is a flowchart showing an example of the processing procedure of the temperature correction calculation unit 827.

The temperature correction calculation unit 827 determines whether the battery temperature T is equal to or lower than the predetermined temperature (step S30). When the temperature T is equal to or lower than the predetermined temperature (step S30: Yes), the temperature correction calculation unit 827 increases the charge / discharge power (step S31).

When the storage battery 7 is used at a high temperature of a predetermined value or higher, deterioration progresses, but at a too low temperature, the battery performance cannot be exhibited. Therefore, by increasing the charge / discharge power when the battery temperature T is equal to or lower than the predetermined temperature, the battery temperature can be raised and the battery performance can be stably exhibited. Further, since the absolute value of the slope of the system output Psys tends to decrease by increasing the charge / discharge power, the fluctuation does not exceed the permissible range of the system output Psys.

[Embodiment 2]
FIG. 9 is a block diagram showing the overall configuration of the renewable energy power generation system 110 according to the second embodiment of the present invention. In the second embodiment, instead of the control controller 8 in the power generation system 100 of the first embodiment, there is a control controller 12 that transmits a command value of the power generation output limit Ppv_lim to the solar PCS5.

FIG. 10 is a block diagram of the integrated controller 12 according to the second embodiment.

The control controller 12 has a system target value calculation unit 81, an output correction unit 82, a fluctuation rate correction unit 83, and a power generation output limiting unit 84. The output correction unit 82 corrects the initial charge / discharge target value PBatt ^*** and outputs the intermediate charge / discharge target value PBatt ^**, as in the first embodiment.

In the first embodiment, the SOC and charging power reach the upper limit values when the storage battery 7 is charged, and the output correction unit 82 corrects the initial charge / discharge target value PBatt ^*** to the intermediate charge / discharge target value PBatt ^** . In that case, that is, when the target value of the charging power decreases, the system output Psys may fluctuate (increase) due to the differential power (PBatt ^***- PBatt ^** ) and deviate from the fluctuation range of the predetermined range. There is.

Therefore, in the present embodiment, the power generation output limiting unit 84 may suppress the power generation output power Ppv by the amount of the above differential power (PBatt ^*** −PBatt ^** ). As a result, fluctuations in the system output Psys can be suppressed within a predetermined range.

FIG. 11 is an explanatory diagram showing an output correction method by the power generation output limiting unit 84.
The upper row shows the time change of the system output. The lower row shows the time change of charge / discharge power.
The power generation output limiting unit 84 accepts Pbatt ^***- Pbatt ^** as an input. While the initial charge / discharge target value PBatt ^*** is not corrected by the output correction unit 82, the input of the power generation output limiting unit 84 is 0. At time t5, the charging power reaches the allowable charging power. Therefore, as described in the first embodiment, the output correction unit 82 sets the initial charge / discharge target value PBatt ^*** to the intermediate charge / discharge target value PBatt ^** . It will be corrected. The power generation output limiting unit 84 instructs the PCS 5 to reduce the generated output power Ppv by setting this differential power (PBatt ^***- PBatt ^** ) as Ppv_lim. As a result, as shown in the upper part of FIG. 11, the power generated from the PCS 5 is output as the generated output power Ppv by Ppv_lim less.

As a result, fluctuations in the system output Psys can be suppressed within a predetermined range.

FIG. 12 is a flowchart showing a process of correcting the power generation output power Ppv based on the allowable power Pollow.

First, the output correction unit 82 determines whether or not the initial charge / discharge target value PBatt ^*** approaches or exceeds the allowable charging power (step 40). When the initial charge / discharge target value Pbatt ^*** exceeds the allowable charge power (step 40: Yes), the output correction unit 82 determines the intermediate charge / discharge target value PBatt ^** so that the charge power does not exceed the allowable charge power. Is calculated (step 41).

The power generation output limiting unit 84 notifies the PCS5 of the difference between the initial charge / discharge target value Pbatt ^*** and the intermediate charge / discharge target value Pbatt ^** generated by reducing the charging power in step 41 as the power generation output limit Ppv_lim. Then, the generated output power Ppv is limited between the time t5 and Δt (step 42).

FIG. 13 is a flowchart showing a process of correcting the generated output power Ppv based on the temperature of the storage battery 7.

First, the output correction unit 82 determines whether or not the temperature of the storage battery 7 is equal to or higher than a predetermined temperature (step 50). When the temperature of the storage battery 7 is equal to or higher than the predetermined temperature (step 50: Yes), the output correction unit 82 calculates the intermediate charge / discharge target value Pbatt ^** so that the charging power does not exceed the allowable charging power (step 51). ).

The power generation output limiting unit 84 notifies the PCS5 of the difference between the initial charge / discharge target value Pbatt ^*** and the intermediate charge / discharge target value Pbatt ^** generated by reducing the charging power in step 51 as Ppv_lim to generate power. The output power Ppv is limited (step 52).

In this embodiment, the case where the charge / discharge power and the temperature of the storage battery 7 are controlled so as not to exceed the predetermined range is described as an example, but the output correction unit 82 and the output correction unit 82 and the SOC are described so as to be within the predetermined range. The power generation output limiting unit 84 may perform the same control.

[Embodiment 3]
FIG. 14 is an overall view of the renewable energy power generation system 120 according to the third embodiment of the present invention. The power generation system 120 of the third embodiment has a configuration in which a power generation amount prediction unit 13 is added to the power generation system 110 of the second embodiment.

The control controller 12 calculates the system output target value Psys ^* using the power generation prediction value Ppv_pre of the power generation amount prediction unit 13. According to this embodiment, it is possible to control in advance against sudden changes in power generation output by predicting the power generation output of renewable energy power generation whose power generation is likely to fluctuate due to weather such as solar power generation and wind power generation. Become.

FIG. 15 is a block diagram showing the relationship between the control controller 12 and the power generation amount prediction unit 13 in the third embodiment.

As shown in the figure, the power generation prediction value Ppv_pre, which is the output of the power generation amount prediction unit 13, is the input value to the system target value calculation unit 81 of the control controller 12. The system target value calculation unit 81 creates a system output target value Psys ^* that passes through the center of fluctuation of the power generation predicted value Ppv_pre. For example, the system target value calculation unit 81 may smooth the power generation prediction value Ppv_pre to create the system output target value Psys ^* .

FIG. 16 is an explanatory diagram showing an output correction method according to the third embodiment.

Since the system output target value Psys ^* is created as described above, the system output Psys passes through the center of fluctuation of the generated output power Ppv. As a result, the charging and discharging of the charge / discharge output PBatt are balanced, so that sudden charging or sudden discharging is less likely to occur. Therefore, it becomes easy to prevent the charge / discharge output PBatt from deviating from the allowable power Pollow and the battery temperature T from rising and exceeding the upper limit temperature. As a result, not only the fluctuation of the system output Psys can be suppressed within a predetermined range, but also the deterioration of the storage battery 7 can be suppressed.

[Embodiment 4]
FIG. 17 is an overall view of the renewable energy power generation system 130 according to the fourth embodiment of the present invention. The power generation system 130 of the fourth embodiment has a configuration in which the solar radiation amount measuring unit 14 and the solar radiation amount conversion unit 15 are added to the power generation system 110 of the second embodiment.

The solar radiation amount conversion unit 15 converts the solar radiation amount measured by the solar radiation amount measurement unit 14 to calculate the solar radiation amount conversion power Psolor. The solar radiation conversion power Psolor is a predicted value of the power generation amount based on the solar radiation amount. Instead of the generated power monitor value Ppv_fb of the first and second embodiments, the solar radiation amount conversion power Psolor is input to the control controller 12.

FIG. 18 is a block diagram showing the relationship between the integrated controller 12 and the solar radiation amount conversion unit 15 in the fourth embodiment.

As shown in the figure, the solar radiation conversion power Psolor, which is the output of the solar radiation conversion unit 15, is an input value to the system target value calculation unit 81 of the control controller 12. The system target value calculation unit 81 creates a system output target value Psys ^* that passes through the center of fluctuation of the power generation predicted value Ppv based on the solar radiation conversion power Psolor. For example, the system target value calculation unit 81 may create a system output target value Psys ^* by smoothing the solar radiation conversion power Psolor.

FIG. 19 is an explanatory diagram showing a method of creating a predicted waveform of generated power according to the fourth embodiment.

For example, the system target value calculation unit 81 performs a moving average process on the solar radiation amount conversion power Psolor created by the solar radiation amount conversion unit 15, and calculates the moving average Psolor_MA of the solar radiation amount conversion power. The system output target value Psys ^* may be obtained by translating the calculated moving average Psolor_MA of the solar radiation amount conversion power and matching it with the rising timing of the actual power generation output power Ppv.

Since the expensive power generation amount prediction unit 13 is not used in the present embodiment, the same effect as that of the third embodiment can be obtained at low cost.

According to this embodiment, since the system output is suppressed within the permissible range, deviation can be avoided and the amount of power sold can be secured. Further, since the battery is used within the usable range, deterioration of the battery can be suppressed.

1 Power generation device 2 Power storage device 3 Power control device 4 Solar panel 5 Solar power conditioner 6 Power conditioner for storage battery 8, 12 Control controller 13 Power generation amount prediction unit 14 Solar radiation amount measurement unit 15 Solar radiation amount conversion unit 81 System target Value calculation unit 82 Output correction unit 83 Fluctuation rate correction unit 84 Power generation output limitation unit 821 SOC judgment unit 822 Temperature judgment unit 823 Allowable power judgment unit 824 Switching unit 825 Switch 828 Correction calculation unit 827 Temperature correction calculation unit 828 Allowable power correction calculation unit

Claims (10)

It is a power control device that controls the power output from a power generation device having a power generation device using renewable energy and a power storage device.
A target output calculation unit that smoothes the monitor value of the generated power of the power generation device to generate the first output target value, and
The first output target value and the first output target value are set so that the temporal fluctuation of the combined output power obtained by combining the generated output power which is the output from the power generation device and the charge / discharge power from the power storage device is suppressed within a predetermined range. With the charge / discharge power correction unit that corrects the first charge / discharge power target value, which is the difference from the monitor value, to the second charge / discharge power target value based on the temperature of the power storage device or the allowable charge / discharge power of the power storage device. Have,
When the first charge / discharge power target value is not within the allowable charge / discharge power range and the temperature of the power generation device is equal to or lower than a predetermined temperature, the charge / discharge power correction unit performs the first charge / discharge power. The same value as the target value is set as the second charge / discharge power target value.
A power control device in which the charge / discharge power of the power storage device is controlled based on the second charge / discharge power target value. The charge / discharge power correction unit
A first calculation unit that corrects the first charge / discharge power target value based on the charge rate of the power storage device, and
A second calculation unit that corrects the first charge / discharge power target value based on the temperature of the power storage device, and
Further, it has a third calculation unit that corrects the first charge / discharge power target value based on the allowable charge power and the allowable discharge power of the power storage device.
The power control device according to claim 1, wherein the second charge / discharge power target value is determined based on the calculation result of any one of the first, second, and third calculation units. The charge / discharge power correction unit
When the first charge / discharge power target value approaches or exceeds the allowable charge power or allowable discharge power of the power storage device , the second charge / discharge power target value is within the range of the allowable charge / discharge power. In addition, the second charge / discharge power target value is set so that the combined output power based on the second charge / discharge power target value increases or decreases at the first angle.
When the second charge-discharge power target value reaches a predetermined value, the combined output power based on the second charge-discharge power target value so as to decrease or increase at a second angle, defining the second charge-discharge power target value , The power control device according to claim 1. The power control device according to claim 3 , wherein the first angle and the second angle are set to have the same absolute value. The charge / discharge power correction unit
When the temperature of the power storage device is equal to or higher than the predetermined temperature, the charging power is corrected to the second charge / discharge power target value, which is smaller than the first charge / discharge power target value.
The power control device is
The generated output power becomes a second output target value obtained by reducing the power corresponding to the difference between the first charge / discharge power target value and the second charge / discharge power target value from the first output target value. The power control device according to claim 1, further comprising an output limiting unit that limits the generated output power . The charge / discharge power correction unit
When the first charge / discharge power target value approaches or exceeds the allowable charge power of the power storage device, the charge power is reduced from the first charge / discharge power target value to the second charge / discharge power target value. Correct and
The power control device is
The generated output power becomes a second output target value obtained by reducing the power corresponding to the difference between the first charge / discharge power target value and the second charge / discharge power target value from the first output target value. The power control device according to claim 1, further comprising an output limiting unit that limits the generated output power . Further having a prediction system for predicting the amount of power generated by the power generation device,
The target output calculating unit, wherein the monitor value of the generated power generations forte, the treated smooth the prediction value of the predicted power generation amount prediction system, to generate the first output target value, claim 1. The power control device according to 1. The prediction system is
Insolation measurement unit that measures the amount of solar radiation,
Further, it has a solar radiation amount conversion unit that predicts the generated power amount of the power generation device based on the solar radiation amount measured by the solar radiation amount measuring unit.
The target output calculating unit, wherein said monitoring value to cash forte of generated power, and smoothed predicted value of the predicted power generation amount of the solar radiation conversion unit generates the first output target value, The power control device according to claim 7 . It is a power control method performed by a power control device that controls power output from a power generation device having a power generation device using renewable energy and a power storage device.
The target output calculation unit smoothes the monitor value of the generated power of the power generation device to generate the first output target value.
The charge / discharge power correction unit suppresses the temporal fluctuation of the combined output power obtained by combining the power generation output power output from the power generation device and the charge / discharge power from the power storage device within a predetermined range. The first charge / discharge power target value, which is the difference between the first output target value and the monitor value, is corrected to the second charge / discharge power target value based on the temperature of the power storage device or the allowable charge / discharge power of the power storage device. And
When the first charge / discharge power target value is not within the allowable charge / discharge power range and the temperature of the power generation device is equal to or lower than a predetermined temperature, the charge / discharge power correction unit determines the first charge / discharge power. The same value as the target value is set as the second charge / discharge power target value.
A method in which the charge / discharge power of the power storage device is controlled based on the second charge / discharge power target value. A power generation system having a power generation device using renewable energy and a power storage device.
A power generation monitor unit that measures the generated power of the power generation device and outputs a monitor value of the generated power.
And the target output calculating unit which generates a first output target value by processing smoothing the monitor value of the generated power to the power generation monitoring unit is output,
The first output target value and the first output target value are set so that the temporal fluctuation of the combined output power obtained by combining the generated output power which is the output from the power generation device and the charge / discharge power from the power storage device is suppressed within a predetermined range. With the charge / discharge power correction unit that corrects the first charge / discharge power target value, which is the difference from the monitor value, to the second charge / discharge power target value based on the temperature of the power storage device or the allowable charge / discharge power of the power storage device. ,
Possess a control unit for controlling the charge-discharge electric power of said power storage device based on the second charge-discharge power target value,
When the first charge / discharge power target value is not within the allowable charge / discharge power range and the temperature of the power generation device is equal to or lower than a predetermined temperature, the charge / discharge power correction unit performs the first charge / discharge power. A power generation system in which the same value as the target value is set as the second charge / discharge power target value .

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