JP4665831B2 - Power stabilization system, control device, and control program thereof - Google Patents

Description

  The present invention relates to a technique for stabilizing power fluctuations caused by a distributed power source using a power storage device.

  In recent years, interconnection of distributed power sources using natural energy such as wind power and sunlight has increased. However, since the output of a distributed power source that uses natural energy fluctuates from moment to moment depending on natural conditions such as wind speed, system frequency and voltage fluctuations occur especially in weak power systems such as remote areas and remote islands. It may become.

  Therefore, a power stabilization system has been developed that compensates for output fluctuations of distributed power sources using natural energy by absorbing or discharging power using a power storage device such as a flywheel or secondary battery. Has been. For example, when the output fluctuation of the wind power generator is compensated, if the power output of the wind power generator is increased, the power discharge of the power storage device is reduced or the power absorption is increased, while the power output of the wind power generator is increased. If so, it reduces the power absorption of the power storage device or increases the power release. This compensates for power fluctuations at the connection point between the wind power generator and the power storage device.

  By the way, in power storage devices and power converters, losses occur during charging and discharging, so the average stored power amount stored in the power storage device gradually decreases and eventually reaches the lower limit value of stored power amount. The fluctuation compensation effect cannot be obtained. In addition, when the average value of the active power fluctuation amount is biased in the direction of charging the power storage device, the average stored power amount stored in the power storage device gradually increases, and finally the upper limit of the stored power amount The power fluctuation compensation effect cannot be obtained. Therefore, various control methods have been proposed to correct the average bias of the charge / discharge amount of the power storage device and prevent the stored power amount from sticking to the stored power amount upper and lower limits over the long term. Yes.

  For example, in the flywheel control device, the rotational speed is set to the target based on the difference between the rotational speed of the flywheel corresponding to the stored electric energy and the target rotational speed set between the rotational speed upper limit value and the lower limit value. A technique for controlling the average bias of the charge / discharge amount of the flywheel by adding a correction signal to the output command value to the flywheel so as to approach the rotation speed is provided (for example, Patent Document 1).

In addition, in the control device for the secondary battery, two upper and lower threshold values are set in advance within the allowable range of the terminal voltage, and the terminal voltage of the secondary battery corresponding to the stored electric energy exceeds these threshold values. In this case, there is provided a technique for controlling the average bias of the charge / discharge amount of the secondary battery by correcting the output command value to the secondary battery so as to approach the intermediate direction of the terminal voltage allowable range. (For example, Non-Patent Document 1). The correction here is performed by adding the correction value to the compensation target value obtained by removing the fluctuation component from the active power measurement value of the distributed power source.
JP 2001-339995 A Feasibility study of wind power generation with storage battery, NEDO-NP-0004, February 2002

  There are upper and lower limits in the output range of the distributed power source. When the output of the distributed power source is close to the output lower limit value, the output of the distributed power source does not fall below the output lower limit value, so that most of the power fluctuation occurs in the direction in which the output increases, that is, the rising direction. However, if the stored power amount is insufficient, the power storage device cannot absorb the increasing power fluctuation component, and the power fluctuation compensation effect cannot be obtained after the stored power amount reaches the upper limit value of the stored power amount. was there.

  Similarly, when the output of the distributed power source is in the vicinity of the output upper limit value, the output of the distributed power source does not exceed the output upper limit value. Therefore, most of the power fluctuation occurs in the direction in which the output decreases, that is, in the falling direction. However, when the amount of stored power is insufficient, the power fluctuation component that decreases can not be compensated for by the stored power amount of the power storage device, and the power fluctuation compensation effect cannot be obtained after the stored power amount reaches the lower limit value of the stored power amount. There was a problem.

  In the prior art, the average bias of the charge / discharge amount of the power storage device is corrected according to the stored power amount. However, there has been no correction technique for securing a stored power amount or a stored power amount free capacity in advance in preparation for power fluctuations that occur when the distributed power supply output rises or falls.

  The present invention secures a storage power amount necessary for power fluctuation compensation at the time of rising or falling of a distributed power source according to the output of the distributed power source, or a free space capacity of the stored power source. It is an object of the present invention to provide a technique that enables effective power fluctuation compensation for power fluctuation at the time of rising or falling.

  In order to solve the above problem, a power stabilization system according to the present invention is connected to an AC power system together with a distributed power source, and is a power stabilization system for suppressing fluctuations in active power of the distributed power source, A power storage device for storing power and charging / discharging the AC power system, an active power detection means for detecting active power of the distributed power source as an active power measurement value, and a stored power amount of the power storage device Or a stored power amount detecting means for detecting a signal corresponding to the stored power amount, a compensation power calculating means for calculating compensation power based on a fluctuation component of the active power measurement value, and the stored power amount is an upper limit of stored power amount If the stored power amount is within a predetermined range from the lower limit value of the stored power amount, a compensation power correction signal is generated in a direction of discharging from the power storage device. Compensation power correction signal generating means for generating a compensation power correction signal in a charging direction, and compensation power correction for correcting the compensation power based on the compensation power and the compensation power correction signal to generate a compensation compensation power Means, power converter control means for transmitting a power converter output command according to the corrected compensation power, and the power storage device and the alternating current according to a power converter output command issued from the power converter control means. A power converter that mutually converts charge / discharge power between the power system and the compensation power correction signal generation means, when the active power measurement value is within a predetermined range from the output lower limit value of the distributed power source, The compensation power correction signal is generated so as to promote the correction processing performed in the direction of discharging from the power storage device in the compensation power correction means, and / or the active power measurement value is output from the distributed power source. If there from the upper limit value within a predetermined range, it can be realized by generating the compensating power correction signal so as to facilitate the correction process performed in the direction of charging the power storage device in the compensating power correcting means.

  According to the power stabilization system having the above configuration, in the compensation power correction signal generating means, the stored power amount is within a predetermined range from the stored power amount upper limit value Emax (EH to Emax, where EH is the upper limit of the stored power amount). If it is determined that the threshold value, but EH <Emax, is generated, a compensation power correction signal is generated in the direction of discharging from the power storage device. To prevent the situation. Here, when the output of the distributed power source is within a predetermined range from the output lower limit value Pmin (Pmin to PL, where PL is the output lower limit threshold, where Pmin <PL), the power storage in the compensation power correction means The compensation power correction signal is generated so as to accelerate the correction process performed in the direction of discharging from the apparatus. For example, by expanding the determination range (EH ′ to Emax, where EH ′ is the changed storage power amount upper limit threshold, where EH ′ <EH), the compensation power correction signal in the direction of discharging from the power storage device (Prompt the start timing of correction, extend the correction period). Alternatively, by increasing the compensation power correction signal in the direction of discharging from the power storage device, the correction effect performed in the direction of discharging from the power storage device is enhanced more than usual. As a result, it is possible to secure a free storage power amount necessary for absorbing power fluctuations in the rising direction of the distributed power source. Note that even if the output of the distributed power source is within a predetermined range (Pmin to PL) from the output lower limit value Pmin, the discharge direction is not corrected if the power storage device has a sufficient storage power capacity, which is unnecessary. There is no correction. As a result, it is possible to reduce the risk that the power storage device cannot absorb the increasing power fluctuation component and cannot compensate for the power fluctuation, and effectively compensate for the power fluctuation when the distributed power source is started up.

  Similarly, in the compensation power correction signal generating means, the stored power amount is within a predetermined range from the stored power amount lower limit value Emin (Emin to EL, where EL is a stored power amount lower limit threshold, where Emin <EL). If it is determined that the power is stored in the power storage device, a compensation power correction signal is generated in a direction in which the power storage device is charged. Here, when the output of the distributed power source is within a predetermined range from the output upper limit value Pmax (PH to Pmax, where PH is the output upper limit threshold, where PH <Pmax), the power storage in the compensation power correction means The compensation power correction signal is generated so as to accelerate the correction process performed in the direction of charging the device. For example, by expanding the determination range (Emin to EL ′, where EL ′ is a lower threshold value of the stored power amount after change, where EL <EL ′), a compensation power correction signal in the direction of charging the power storage device (Prompt the start timing of correction, extend the correction period). Alternatively, by increasing the compensation power correction signal in the direction of charging the power storage device, the correction effect performed in the direction of charging the power storage device is enhanced than usual. As a result, the amount of stored power necessary to compensate for power fluctuations in the falling direction of the distributed power supply can be ensured. Even if the output of the distributed power source is within a predetermined range (PH to Pmax) from the output upper limit value Pmax, if the power storage device has a sufficient amount of stored power, the charging direction is not corrected. There is no such thing. As a result, it is possible to reduce the risk that the power storage device cannot fully compensate for the decreasing power fluctuation component and cannot compensate for the power fluctuation, and to effectively compensate for the power fluctuation when the distributed power supply falls.

  The compensation power correction signal generation means outputs a stored power amount correction signal in a direction to increase the stored power amount when the active power measurement value is within a predetermined range from the output lower limit value of the distributed power source, and And / or a stored power amount correction signal calculating means for outputting a stored power amount correction signal for reducing the stored power amount when the active power measurement value is within a predetermined range from the output upper limit value of the distributed power source, and the stored power amount And a stored power amount correcting means for correcting the stored power amount based on the stored power amount correction signal and generating a corrected stored power amount, and the corrected stored power amount is predetermined from a stored power amount upper limit value of the power storage device. The compensation power correction signal is output in the direction of discharging from the power storage device, and when the corrected storage power amount is within a predetermined range from the storage energy lower limit of the power storage device, the power storage To equipment Compensation power correction signal calculation means for outputting the compensation power correction signal in the charging direction may be used.

  According to the compensation power correction signal generation unit configured as described above, when the compensation power correction signal calculation unit determines that the stored power amount is within a predetermined range (EH to Emax) from the stored power amount upper limit value Emax, A compensation power correction signal is generated in a direction of discharging from the power storage device, and when it is determined that the stored power amount is within a predetermined range (Emin to EL) from the stored power amount lower limit Emin, to the power storage device By generating the compensation power correction signal in the charging direction, a state where the stored power amount sticks to the upper and lower limit values in the long term is prevented.

  By the way, when the output of the distributed power source is within a predetermined range (Pmin to PL) from the output lower limit value Pmin, the stored power amount correction signal calculation means outputs the stored power amount correction signal in the direction of increasing the stored power amount. Then, the stored power amount correcting means corrects the stored power amount based on the stored power amount and the stored power amount correction signal to generate a corrected stored power amount. That is, when the output of the distributed power source is within a predetermined range (Pmin to PL) from the output lower limit value Pmin, the corrected stored power amount is made closer to the stored power amount upper limit value than the actual stored power amount. Thereby, the compensation power correction signal calculation means makes it easy to generate a compensation power correction signal in the direction of discharging from the power storage device. Alternatively, the compensation power correction signal is increased in the direction of discharging from the power storage device. As a result, it is possible to secure a free storage power amount necessary for absorbing the power fluctuation in the rising direction of the distributed power source.

  Similarly, when the output of the distributed power source is within a predetermined range (PH to Pmax) from the output upper limit value Pmax in the stored power amount correction signal calculation means, the stored power amount correction signal is set so as to decrease the stored power amount. The stored power amount correction means corrects the stored power amount based on the stored power amount and the stored power amount correction signal, and generates a corrected stored power amount. That is, when the output of the distributed power source is within a predetermined range (PH to Pmax) from the output upper limit value Pmax, the corrected stored power amount is made closer to the stored power amount lower limit value than the actual stored power amount. Thereby, the compensation power correction signal calculation means makes it easy to generate a compensation power correction signal in the direction of charging the power storage device. Alternatively, the compensation power correction signal is increased in the direction of charging the power storage device. As a result, it is possible to ensure the amount of stored power necessary to compensate for power fluctuations in the falling direction of the distributed power source.

  Further, the stored power amount correction signal calculation means includes a low output correction start threshold Th1, a low output correction end threshold Th2, and a high output correction end within the output possible range of the distributed power source. When the threshold value Th3 and the high output correction start threshold value Th4 are set to satisfy Th1 <Th2 <Th3 <Th4, and the active power measurement value decreases and falls below the Th1, the stored power amount is reduced. When the output of the stored power amount correction signal is started in the direction of increasing, and then the active power measurement value rises and exceeds the Th2, the output of the stored power amount correction signal is stopped, and the active power measurement value is When it rises and exceeds Th4, it starts outputting the stored power amount correction signal in a direction to decrease the stored power amount. After that, when the active power measurement value decreases and falls below Th3, the stored power amount Amount correction signal It may be realized by acting to stop the force.

  According to the stored power amount correction signal calculation means having the above configuration, the low output correction start threshold value Th1 and the low output correction end threshold value Th2 are set close to the output lower limit value of the distributed power source, By setting the correction end threshold Th3 and the high output correction start threshold Th4 close to the output upper limit value of the distributed power source, the output of the distributed power source is in the vicinity of the output lower limit value Pmin or the output upper limit value Pmax. Since the stored power amount correction signal can be output only in some cases, an unnecessary correction operation can be prevented when the distributed power source is not near the output lower limit value Pmin or the output upper limit value Pmax. Since the correction start threshold value and the correction end threshold value are set separately, once the output of the stored energy correction signal is started, the output of the distributed power source fluctuates greatly (approaching the correction end threshold value). The output will not stop unless the output is stopped, and after the output stops, the output will not resume unless the output of the distributed power source fluctuates significantly (so that it reaches the correction start threshold). Can be prevented from being frequently turned on and off (ON / OFF).

  Alternatively, when the stored power amount exceeds the stored power amount upper limit threshold EH, the compensated power correction signal generating unit outputs the compensated power correction signal in a direction of discharging from the power storage device, and the stored power amount is Compensation power correction signal calculation means for outputting the compensation power correction signal in a direction to charge the power storage device when the stored power amount lower limit threshold EL is below, and an active power measurement value is an output lower limit of the distributed power source When the value is within a predetermined range, a threshold value correction signal is output in a direction to decrease the stored power amount upper limit threshold value EH, and / or the active power measurement value is determined from the output upper limit value of the distributed power source. When it is within the predetermined range, it may be constituted by threshold correction signal calculation means for outputting a threshold correction signal in a direction to increase the stored power amount lower limit threshold EL.

  According to the compensation power correction signal generation means having the above configuration, in the compensation power correction signal calculation means, when the stored power amount exceeds the stored power amount upper limit threshold EH, the compensation power in the direction of discharging from the power storage device. A correction signal is generated, and when the stored power amount falls below the stored power amount lower limit threshold EL, a compensation power correction signal is generated in a direction to charge the power storage device, so that the stored power amount is usually long-term. The state where it sticks to the upper and lower limit values is prevented.

  By the way, in the threshold correction signal calculation means, when the output of the distributed power source is within a predetermined range (Pmin to PL) from the output lower limit value Pmin, the threshold value is set so as to decrease the stored power amount upper limit threshold value EH. Output a correction signal. Thereby, in the compensation power correction signal calculation means, it becomes easy to apply correction in the direction of discharging from the power storage device, and the storage power amount vacant capacity necessary for absorbing the power fluctuation in the rising direction of the distributed power source is secured. be able to.

  Similarly, in the threshold correction signal calculation means, when the output of the distributed power source is within a predetermined range (PH to Pmax) from the output upper limit value Pmax, the threshold is set so as to increase the stored power amount lower limit threshold EL. A value correction signal is output. Thereby, in the compensation power correction signal calculation means, correction is easily applied in the charging direction of the power storage device, and the amount of stored power necessary for compensating for the power fluctuation in the falling direction of the distributed power source is ensured. Can do.

  Further, the threshold value correction signal calculation means includes a low output correction start threshold value Th5, a low output correction end threshold value Th6, and a high output correction end within the output possible range of the distributed power source. When the threshold value Th7 and the high output correction start threshold value Th8 are set such that Th5 <Th6 <Th7 <Th8, and the active power measurement value decreases and falls below the Th5, the stored power amount The output of the threshold correction signal is started in the direction of decreasing the upper threshold EH, and then the output of the threshold correction signal is stopped when the active power measurement value rises and exceeds Th6. When the active power measurement value rises and exceeds the Th8, output of the threshold correction signal is started in the direction of increasing the stored power amount lower limit threshold EL, and then the active power measurement value decreases. And below the Th7 If it may be achieved by acting to stop the output of the threshold correction signal.

  According to the threshold value correction signal calculation means having the above configuration, the low output correction start threshold value Th5 and the low output correction end threshold value Th6 are set close to the output lower limit value of the distributed power source, By setting the correction end threshold Th7 and the high output correction start threshold Th8 close to the output upper limit value of the distributed power source, the output of the distributed power source is in the vicinity of the output lower limit value Pmin or the output upper limit value Pmax. Since the threshold value correction signal can be output only in some cases, unnecessary correction operation can be prevented when the output of the distributed power source is not near the output lower limit value Pmin or the output upper limit value Pmax. In addition, since the correction start threshold value and the correction end threshold value are set separately, once the output of the threshold correction signal is started, the output of the distributed power source greatly fluctuates (as the correction end threshold is applied). The output will not stop unless the output is stopped, and after the output stops, the output will not resume unless the output of the distributed power source fluctuates significantly (so that it reaches the correction start threshold). Can be prevented from being frequently turned on and off (ON / OFF).

  Note that the present invention is not limited to the power stabilization system. A control device, a method, and a program for realizing the above method are also included in the present invention.

  According to the present invention, the amount of stored power or the amount of stored power required to compensate for power fluctuations at the rising or falling of a distributed power source is ensured while preventing unnecessary correction operations and frequent correction operations. Thus, effective power fluctuation compensation is possible.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described in detail with reference to the drawings.
FIG. 1 is a conceptual diagram showing an example of the configuration of a power stabilization system according to an embodiment of the present invention. A power stabilization system 10 illustrated in FIG. 1 includes a power storage device 5, a power converter 6, and a control device 1, and is connected to the power system 4 via a transformer 7.

  In the following description, it is assumed that the power stabilization system 10 performs output fluctuation compensation of a distributed power source using natural energy. As an example, the wind power generator 2 is connected to the power system 4 via the transformer 3. Is connected. In addition, as long as it is a distributed power source linked to an AC power system, it is not limited to the wind power generator 2 and may be solar power generation, for example.

The power storage device 5 is, for example, a flywheel, a secondary battery, a capacitor, or the like.
The power converter 6 is connected to the power system 4 and the power storage based on the power converter output command value PO from the control device 1 (here, the direction in which the power is discharged from the power storage device 5 is “positive”). The power PS is exchanged with the device 5. When the power storage device 5 is a flywheel, the AC power on the flywheel side and the AC power on the power system 4 side are converted in both directions. When the power storage device 5 is a secondary battery / capacitor or the like, the DC power on the secondary battery / capacitor side and the AC power on the power system 4 side are converted bidirectionally.

The control device 1 includes an active power detection unit 11, a compensation power calculation unit 12, a stored power amount detection unit 14, a compensation power correction signal generation unit 15, a compensation power correction unit 16, a power converter control unit 13, and the like.
Although not particularly shown, the control device 1 includes a CPU and the like, a storage device such as a memory and various storage media (hard disk, etc.), etc., and various correction signal calculation processing and compensation power calculation described below. The processing and the control processing of the power converter may be realized by hardware, or may be realized by the CPU reading and executing a predetermined application program stored in the storage device. Further, when realized by hardware, it may be controlled using a digital circuit such as a programmable controller, or may be realized by an analog control circuit such as an operational amplifier.

The active power detection unit 11 detects the active power measurement value PG of the wind power generator 2 based on the voltage / current value at the output end of the wind power generator 2.
Compensation power calculation unit 12 is composed of a high-pass filter or the like, extracts active power fluctuation component from active power measurement value PG, and compensates power ΔPG (here, the direction in which power is discharged from power storage device 5 is “positive”. )). Note that the compensation power calculation unit 12 may use any number of high-pass filters or may have a configuration in which several stages of high-pass filters are connected in series as long as it has a function of extracting the active power fluctuation component. Alternatively, a filter that removes fluctuations such as a low-pass filter (any number of low-pass filters may be used as long as it has a function of removing active power fluctuation components, or a configuration in which several stages of low-pass filters are connected in series. It is also possible to calculate the compensation target value PA by removing the active power fluctuation component from the active power measurement value PG by smoothing processing such as moving average, and subtract the active power measurement value PG from the compensation target value PA. By doing so, it may be configured to calculate the compensation power ΔPG.

  The stored power amount detection unit 14 detects / calculates the stored power amount ES of the power storage device 5 directly or indirectly. For example, when the power storage device 5 is a flywheel, the rotational speed of the flywheel is detected. When the power storage device 5 is a secondary battery, a capacitor, or the like, the terminal voltage is detected, and the stored power amount ES is calculated based on the detection result. .

  The compensation power correction signal generation unit 15 is configured such that the stored power amount ES is within a predetermined range from the stored power amount upper limit value Emax (EH to Emax, where EH is a stored power amount upper limit threshold, but EH <Emax). In this case, the compensation power correction signal PC is generated in the direction of discharging from the power storage device 5 (here, the “positive” direction), and the stored power amount ES is within a predetermined range from the stored power amount lower limit Emin (Emin to EL, Here, when EL is at the stored energy lower limit threshold, where Emin <EL, the compensation power correction signal PC is generated in the direction in which the power storage device 5 is charged (here, the “negative” direction). However, when the active power measurement value PG is within a predetermined range from the output lower limit value Pmin of the distributed power supply (Pmin to PL, where PL is the output lower limit threshold, where Pmin <PL), the compensation power correction unit 16 The correction process in the direction of discharging from the power storage device 5 is promoted (increase correction amount, advance correction start timing, extend correction period, etc.), and / or the active power measurement value PG is a distributed power source. When the output upper limit value Pmax is within a predetermined range (PH to Pmax, where PH is an output upper limit threshold, where PH <Pmax), the compensation power correction unit 16 corrects the power storage device 5 in the charging direction. (The increase of the correction amount, the advancement of the correction start timing, the extension of the correction period, etc.) are performed. A more detailed configuration and principle of the compensation power correction signal generation unit 15 will be described in an embodiment described later.

  The compensation power correction unit 16 corrects the compensation power ΔPG, for example, by adding the compensation power correction signal PC to the compensation power ΔPG, and calculates a compensation compensation power ΔPG ′. In this case, the compensation power correction signal PC described above is a positive value when the stored power amount ES is within a predetermined range (EH to Emax) from the stored power amount upper limit value Emax, and the stored power amount ES is the stored power amount. When it is within a predetermined range (Emin to EL) from the lower limit value Emin, it is set to a negative value.

  The power converter control unit 13 generates a power converter output command value PO according to the magnitude of the corrected compensation power ΔPG ′ calculated by the compensation power correction unit 16, and power based on the power converter output command value PO. The converter 6 is controlled, and the power storage device 5 is charged and discharged with the power PS.

  The control device according to the present embodiment having the above-described configuration is characterized in that, in the compensated power correction signal generation unit 15, the active power measurement value PG is within a predetermined range (Pmin to PL) from the output lower limit value Pmin of the distributed power supply. In some cases, the compensation power correction unit 16 promotes correction processing in the direction of discharging from the power storage device 5 (increase correction amount, advance correction start timing, extend correction period, etc.) and / or be effective When the power measurement value PG is within a predetermined range (PH to Pmax) from the output upper limit value Pmax of the distributed power source, the compensation power correction unit 16 accelerates the correction process in the direction of charging the power storage device 5 (correction amount). , Increase the correction start timing, extend the correction period, etc.).

A first configuration example for realizing the compensation power correction signal generation unit 15 is shown in FIG.
In the stored power amount correction signal calculation unit 21, when the active power measurement value PG is within a predetermined range (Pmin to PL) from the output lower limit value Pmin of the distributed power source, the stored power amount correction is performed in the direction of increasing the stored power amount. When the signal EC is output and / or the active power measurement value PG is within a predetermined range (PH to Pmax) from the output upper limit value Pmax of the distributed power source, the stored power amount correction signal EC for decreasing the stored power amount Is output.

  FIG. 2 shows an example in which the stored power amount correction signal calculation unit 21 provides a correction start threshold value and a correction end threshold value for the output lower limit threshold value PL and the output upper limit threshold value PH, respectively. That is, a low output correction start threshold Th1, a low output correction end threshold Th2, a high output correction end threshold Th3, and a high output correction start threshold Th4 are provided.

And it sets so that it may become Th1 <Th2 <Th3 <Th4 within the output possible range of a distributed power supply.
Further, a stored power amount correction signal ECp (≧ 0.0) at low output and a stored power amount correction signal ECm (≦ 0.0) at high output are set.

  The stored power amount correction signal calculation unit 21 receives the active power measurement value PG calculated by the active power detection unit as an input, and stores based on the relationship between the active power measurement value PG and each of Th1, Th2, Th3, and Th4. As the power amount correction signal EC, any one of the stored power amount correction signal ECm, 0 (zero) and the stored power amount correction signal ECp is output.

  The stored power amount correction signal calculation unit 21 starts outputting the stored power amount correction signal ECp as the stored power amount correction signal EC when the active power measurement value PG decreases and falls below the low output correction start threshold value Th1. To do. The stored power amount correction signal ECp is a positive signal, and the stored power amount correction unit 22 in the subsequent stage adds the stored power amount correction signal EC to the stored power amount ES, so that the corrected stored power amount ES ′ is the stored power amount ES. On the other hand, the stored power amount correction signal ECp is increased.

  Thereafter, when the active power measurement value PG increases and exceeds the low output correction end threshold Th2, the stored power amount correction signal calculation unit 21 stops outputting the stored power amount correction signal ECp. That is, the stored power amount correction signal EC becomes zero.

  Similarly, when the active power measurement value PG increases and exceeds the high power correction start threshold value Th4, the stored power amount correction signal calculation unit 21 sets the stored power amount correction signal ECm as the stored power amount correction signal EC. Start output. The stored power amount correction signal ECm is a negative signal. Since the stored power amount correction unit 22 described later adds the stored power amount correction signal EC to the stored power amount ES, the corrected stored power amount ES ′ is the stored power amount ES. On the other hand, the stored power amount correction signal ECm is decreased.

  After that, when the active power measurement value PG decreases and falls below the high output correction end threshold Th3, the stored power amount correction signal calculation unit 21 stops outputting the stored power amount correction signal ECm. That is, the stored power amount correction signal EC becomes zero.

The stored power amount correction unit 22 corrects the stored power amount ES based on the stored power amount ES and the stored power amount correction signal EC to generate a corrected stored power amount ES ′.
FIG. 2 shows an example of correcting the stored power amount ES by adding the stored power amount correction signal EC to the stored power amount ES and calculating the corrected stored power amount ES ′. This is merely an example, and the stored power amount ES may be corrected by multiplying the stored power amount ES by the stored power amount correction signal EC. However, in that case, in the above-described stored power amount correction signal calculation unit 21, the stored power amount correction signal EC, which is an output signal, has an active power measurement value PG within a predetermined range from the output lower limit Pmin of the distributed power source (Pmin to PL) is a value of 1.0 or more, and when the active power measurement value PG is within a predetermined range (PH to Pmax) from the output upper limit value Pmax of the distributed power source, the value is 1.0 or less. In other cases, it is necessary to configure the stored power amount correction signal calculation unit 21 so that the value becomes 1.0.

  The compensation power correction signal calculation unit 23, when the corrected storage power amount ES ′ is within a predetermined range (EH to Emax) from the storage power amount upper limit value Emax, the direction of discharging from the power storage device, that is, a positive compensation power correction signal. When the PC is output and the corrected storage energy ES ′ is within a predetermined range (Emin to EL) from the storage energy lower limit Emin of the power storage device, the charging direction of the power storage device, that is, the negative compensation power correction The signal PC is output.

FIG. 2 shows an example in which the compensation power correction signal calculation unit 23 is provided with a stored power amount lower limit threshold EL and a stored power amount upper limit threshold EH.
The stored power amount lower limit threshold EL and the stored power amount upper limit threshold EH are within the allowable operating range of the stored power amount ES in the power storage device 5 (for example, between the upper and lower limits of the rotational speed of the flywheel, In the secondary battery, the terminal voltage is set so that EL <EH between the upper and lower limits of the terminal voltage.

Also, a compensation power correction signal PCm (≦ 0.0) at the time of low stored power amount and a compensation power correction signal PCp (≧ 0.0) at the time of high storage power amount are set.
The compensation power correction signal calculation unit 23 receives the correction storage power amount ES ′ as an input, and uses the compensation power correction signal PC as a compensation power correction signal PC based on the relationship between the correction storage power amount ES ′ and each of EL and EH. One of PCm, 0 (zero), and compensation power correction signal PCp is output.

  The compensation power correction signal calculation unit 23 starts outputting the compensation power correction signal PCm as the compensation power correction signal PC when the correction storage power amount ES ′ decreases and falls below the storage power amount lower limit threshold EL. The compensation power correction signal PCm is a negative signal. Since the compensation power correction unit 16 in the subsequent stage adds the compensation power correction signal PC to the compensation power ΔPG, the compensation power compensation signal ΔPG ′ is a compensation power compensation signal for the compensation power ΔPG. It shifts to the direction which charges an electric power storage apparatus by PCm.

  Thereafter, when the corrected stored power amount ES ′ increases and exceeds the stored power amount lower limit threshold EL, the compensation power correction signal calculation unit 23 stops outputting the compensation power correction signal PCm. That is, the compensation power correction signal PC becomes zero.

  Similarly, the compensation power correction signal calculation unit 23 starts outputting the compensation power correction signal PCp as the compensation power correction signal PC when the correction storage power amount ES ′ increases and exceeds the storage power amount upper limit threshold EH. To do. The compensation power correction signal PCp is a positive signal. Since the compensation power correction unit 16 in the subsequent stage adds the compensation power correction signal PC to the compensation power ΔPG, the compensation compensation power ΔPG ′ is a compensation power correction signal with respect to the compensation power ΔPG. The shift is in the direction of discharging from the power storage device 5 by the amount of PCp.

  Thereafter, when the corrected stored power amount ES ′ decreases and falls below the stored power amount upper limit threshold value EH, the compensation power correction signal calculation unit 23 stops outputting the compensation power correction signal PCp. That is, the compensation power correction signal PC becomes zero.

  By configuring the compensation power correction signal generation unit as shown in FIG. 2, in the compensation power correction signal calculation unit 23, the corrected storage power amount ES ′ falls within a predetermined range (EH to Emax) from the storage power amount upper limit value Emax. When it is determined that there is a compensation power correction signal PC in the direction of discharging from the power storage device 5, the corrected storage power amount ES ′ is within a predetermined range (Emin to EL) from the stored power amount lower limit Emin. If it is determined that there is, the compensation power correction signal PC is generated in the direction in which the power storage device 5 is charged, thereby preventing the state where the stored power amount sticks to the upper and lower limit values in the long term.

  By the way, when the output of the distributed power supply is within a predetermined range (Pmin to PL) from the output lower limit value Pmin, the stored power amount ES is increased by the stored power amount correction signal calculation unit 21 and the stored power amount correction unit 22. Corrected in the direction. As a result, the corrected stored power amount ES 'is closer to the stored power amount upper limit value Emax than the actual stored power amount ES, and easily enters a predetermined range (EH to Emax) from the stored power amount upper limit value Emax. This is because when the compensation power correction signal PC is generated in the direction of discharging from the power storage device 5, a predetermined range (EH to Emax) for determining whether or not the compensation power correction signal PC can be generated is expanded (EH ′ to Emax, where EH 'is the same as changing the stored energy upper limit threshold, but EH' <EH, and it is easy to make corrections in the direction of discharging from the power storage device (early correction start timing, correction period Extension). Note that even if the output of the distributed power source is within a predetermined range (Pmin to PL) from the output lower limit value Pmin, if the power storage device 5 has a sufficient storage power capacity, the discharge direction is not corrected, so it is unnecessary. No correction is required. As a result, it is possible to secure an available storage power capacity free capacity for absorbing power fluctuations in the rising direction of the distributed power supply, and the power storage device 5 cannot absorb the increasing power fluctuation components, thus making it impossible to compensate for power fluctuations. It is possible to reduce the risk and effectively compensate for the power fluctuation when the distributed power source is started up.

  Similarly, when the output of the distributed power source is within a predetermined range (PH to Pmax) from the output upper limit value Pmax, the stored power amount ES is calculated by the stored power amount correction signal calculation unit 21 and the stored power amount correction unit 22. It is corrected in the decreasing direction. As a result, the corrected stored power amount ES 'approaches the stored power amount lower limit value Emin than the actual stored power amount ES, and easily enters a predetermined range (Emin to EL) from the stored power amount lower limit value Emin. This is to expand a predetermined range (Emin to EL) for determining whether or not the compensation power correction signal PC can be generated when generating the compensation power correction signal PC in the direction of charging the power storage device 5 (Emin to EL ′, where EL ′ is the same as the stored energy lower limit threshold after change, where EL <EL ′), and the direction in which the power storage device 5 is charged is likely to be corrected (advanced correction start timing, correction period) Extension). Even if the output of the distributed power source is within a predetermined range (PH to Pmax) from the output upper limit value Pmax, the charging direction is not corrected if the power storage device 5 has a sufficient amount of stored power. Will not take. As a result, the amount of stored power necessary to compensate for power fluctuations in the falling direction of the distributed power supply can be ensured, and the power storage device 5 cannot fully compensate for the reduced power fluctuation components, thus making it impossible to compensate for power fluctuations. It is possible to effectively compensate for power fluctuations when the distributed power supply falls.

  In the stored power amount correction signal calculation unit 21, the correction start threshold value and the correction end threshold value (low output correction start threshold value Th1) are respectively set for the output lower limit threshold value PL and the output upper limit threshold value PH. Low output correction end threshold Th2, high output correction end threshold Th3, high output correction start threshold Th4), low output correction start threshold Th1, low output correction end The threshold value Th2 is set close to the output lower limit value Pmin of the distributed power source, and the high power correction end threshold value Th3 and the high output correction start threshold value Th4 are set close to the output upper limit value Pmax of the distributed power source. As a result, the stored power amount correction signal EC can be output only when the output of the distributed power source reaches the vicinity of the output lower limit value Pmin or the output upper limit value Pmax. There it is possible to prevent unnecessary correcting operations when the output lower limit value Pmin vicinity or not an output upper limit value Pmax vicinity. In addition, since the correction start threshold value and the correction end threshold value are set separately, once the output of the stored power amount correction signal EC is started, the output of the distributed power source becomes larger (approaching the correction end threshold value). As long as it does not fluctuate, the output of the stored power amount correction signal EC does not stop, and after the output of the stored power amount correction signal EC stops, the output of the distributed power source becomes larger (approaching the correction start threshold). As long as it does not fluctuate, the output of the stored power amount correction signal EC does not resume, so that it is possible to prevent the correction operation by the stored power amount correction signal EC from being frequently turned on and off (ON / OFF).

FIG. 3 shows another configuration example for realizing the compensation power correction signal calculation unit. The configuration other than the compensation power correction signal calculation unit is as shown in FIG.
The compensation power correction signal calculation unit 23A in FIG. 3 receives the corrected stored power amount ES ′ as an input, and outputs a positive compensation power correction signal PC when the corrected stored power amount ES ′ exceeds a certain reference value TH. When the stored power amount ES ′ falls below a certain reference value TH, a negative compensation power correction signal PC is output, and the absolute value of the signal increases as the corrected stored power amount ES ′ increases from the reference value TH.

  The reference value TH in this configuration can be regarded as reference value TH = stored energy lower limit threshold EL = stored energy upper limit threshold EH. According to this configuration, the corrected stored energy ES ′ is stored energy. When it is determined that the value is within the range of the reference value TH from the upper limit value Emax (TH to Emax, where TH <Emax), the compensation power correction signal PC is generated in the direction of discharging from the power storage device 5, and the corrected stored power amount ES When it is determined that 'is within the range of the stored power amount lower limit value Emin to the reference value TH (Emin to TH, where Emin <TH), the compensation power correction signal PC is generated in the direction in which the power storage device 5 is charged. become.

  When the compensation power correction signal calculation unit is configured as shown in FIG. 3, the correction of the stored power amount ES by the storage power amount correction signal calculation unit 21 and the storage power amount correction unit 22 is performed on the compensation power correction signal calculation unit 23A. It has the following effects.

  When the corrected stored power amount ES ′ is corrected so as to increase from the actual stored power amount ES, the compensation power correction signal PC from the compensation power correction signal calculation unit 23A is (when the actual stored power amount ES is input). Increase). That is, when the output of the distributed power source is within a predetermined range (Pmin to PL) from the output lower limit value Pmin, the compensation power correction signal PC is shifted in the direction of discharging from the power storage device 5, and the compensation power correction is performed. In the part 16, the correction effect is strengthened in the direction of discharging from the power storage device 5. That is, the correction process in which the compensation power correction unit 16 discharges from the power storage device 5 is further promoted. Note that even if the output of the distributed power source is within a predetermined range (Pmin to PL) from the output lower limit value Pmin, if the power storage device 5 has a sufficient storage power capacity, the discharge direction is not corrected, so it is unnecessary. No correction is required. As a result, it is possible to secure an available storage power capacity free capacity for absorbing power fluctuations in the rising direction of the distributed power supply, and the power storage device 5 cannot absorb the increasing power fluctuation components, thus making it impossible to compensate for power fluctuations. It is possible to reduce the risk and effectively compensate for the power fluctuation when the distributed power source is started up.

  Similarly, when the corrected storage power amount ES ′ is corrected so as to be smaller than the actual storage power amount ES, the compensation power correction signal PC from the compensation power correction signal calculation unit 23A (the actual storage power amount ES is input). (Compared to the case). That is, when the output of the distributed power source is within a predetermined range (PH to Pmax) from the output upper limit value Pmax, the compensated power correction signal PC is shifted in the direction of charging the power storage device 5 and compensated power compensation. In the part 16, the correction effect is strengthened in the direction in which the power storage device 5 is charged. In other words, the correction process for charging the power storage device 5 in the compensation power correction unit 16 is further promoted. Even if the output of the distributed power source is within a predetermined range (PH to Pmax) from the output upper limit value Pmax, the charging direction is not corrected if the power storage device 5 has a sufficient amount of stored power. Will not take. As a result, the amount of stored power necessary to compensate for power fluctuations in the falling direction of the distributed power supply can be ensured, and the power storage device 5 cannot fully compensate for the reduced power fluctuation components, thus making it impossible to compensate for power fluctuations. It is possible to effectively compensate for power fluctuations when the distributed power supply falls.

A second configuration example for realizing the compensation power correction signal generation unit is shown in FIG.
In the threshold correction signal calculation unit 31, when the active power measurement value PG is within a predetermined range (Pmin to PL) from the output lower limit value Pmin of the distributed power source, the stored power amount upper limit threshold value EH is decreased. When the threshold correction signal LC is output and / or the active power measurement value PG is within a predetermined range (PH to Pmax) from the output upper limit value Pmax of the distributed power source, the stored power amount lower limit threshold EL The threshold value correction signal LC is output in the direction of increasing.

  FIG. 4 shows an example in which the threshold value correction signal calculation unit 31 provides a correction start threshold value and a correction end threshold value for the output lower limit threshold value PL and the output upper limit threshold value PH, respectively. That is, a low output correction start threshold Th5, a low output correction end threshold Th6, a high output correction end threshold Th7, and a high output correction start threshold Th8 are provided.

And it sets so that it may become Th5 <Th6 <Th7 <Th8 in the output possible range of a distributed power supply.
Further, a threshold correction signal LCm (≦ 0.0) at the time of low output and a threshold correction signal LCp (≧ 0.0) at the time of high output are set.

  The threshold correction signal calculation unit 31 receives the active power measurement value PG calculated by the active power detection unit as an input, and based on the relationship between the active power measurement value PG and each of Th5, Th6, Th7, and Th8. As the threshold correction signal LC, any one of the threshold correction signal LCm, 0 (zero), and the threshold correction signal LCp is output.

  The threshold correction signal calculation unit 31 starts outputting the threshold correction signal LCm as the threshold correction signal LC when the active power measurement value PG decreases and falls below the low output correction start threshold Th5. To do. The threshold value correction signal LCm is a negative signal, and the stored power amount upper limit threshold value EH is decreased by the threshold value correction signal LCm in the compensation power correction signal calculation unit 32 at the subsequent stage.

  Thereafter, when the active power measurement value PG rises and exceeds the low output correction end threshold Th6, the threshold correction signal calculation unit 31 stops outputting the threshold correction signal LCm. That is, the threshold correction signal LC becomes zero.

  Similarly, the threshold correction signal calculation unit 31 calculates the threshold correction signal LCp as the threshold correction signal LC when the active power measurement value PG increases and exceeds the high output correction start threshold Th8. Start output. The threshold correction signal LCp is a positive signal, and the stored power amount lower limit threshold EL is increased by the threshold correction signal LCp in the subsequent compensation power correction signal calculation unit 32.

  Thereafter, when the active power measurement value PG decreases and falls below the high output correction end threshold Th7, the threshold correction signal calculation unit 31 stops outputting the threshold correction signal LCp. That is, the threshold correction signal LC becomes zero.

  When the stored power amount ES is within a predetermined range from the stored power amount upper limit value Emax (EH to Emax, where EH is a stored power amount upper limit threshold value), the compensation power correction signal calculation unit 32 starts from the power storage device 5. A discharging direction, that is, a positive compensation power correction signal PC is output, and the stored energy ES is within a predetermined range from the stored energy lower limit Emin of the power storage device 5 (Emin to EL, where EL is the stored energy lower limit) In the case of the threshold value), the charging direction of the power storage device 5, that is, a negative compensation power correction signal PC is output.

  However, the stored power amount upper limit threshold value EH and / or the stored power amount lower limit threshold value EL change in accordance with the threshold value correction signal LC from the threshold value correction signal calculation unit 31. That is, when the active power measurement value PG is within a predetermined range (Pmin to PL) from the output lower limit value Pmin of the distributed power source, the stored power amount upper limit threshold value EH decreases by the threshold value correction signal LCm, and EH '(Where EH' is the upper threshold value of the stored power amount after the change). And / or when the active power measurement value PG is within a predetermined range (PH to Pmax) from the output upper limit value Pmax of the distributed power source, the stored power amount lower limit threshold EL is increased by the threshold correction signal LCp. EL ′ (where EL ′ is the threshold value for the stored energy lower limit after the change).

  The stored power amount lower limit threshold EL and the stored power amount upper limit threshold EH are within the allowable operating range of the stored power amount ES in the power storage device 5 (for example, between the upper and lower limits of the rotational speed of the flywheel, In the secondary battery, the terminal voltage is set so that EL <EH between the upper and lower limits of the terminal voltage.

Also, a compensation power correction signal PCm (≦ 0.0) at the time of low stored power amount and a compensation power correction signal PCp (≧ 0.0) at the time of high storage power amount are set.
The compensation power correction signal calculation unit 32 receives the stored power amount ES, and based on the relationship between the stored power amount ES and each of EL (EL ′) and EH (EH ′), as the compensation power correction signal PC, One of the compensation power correction signal PCm, 0 (zero) and the compensation power correction signal PCp is output.

  The compensation power correction signal calculation unit 32 starts outputting the compensation power correction signal PCm as the compensation power correction signal PC when the stored power amount ES decreases and falls below the stored power amount lower limit threshold EL (EL ′). . The compensation power correction signal PCm is a negative signal. Since the compensation power correction unit 16 in the subsequent stage adds the compensation power correction signal PC to the compensation power ΔPG, the compensation power compensation signal ΔPG ′ is a compensation power compensation signal for the compensation power ΔPG. The power storage device 5 is shifted in the direction of charging by PCm.

  Thereafter, when the stored power amount ES rises and exceeds the stored power amount lower limit threshold EL (EL ′), the compensation power correction signal calculation unit 32 stops outputting the compensation power correction signal PCm. That is, the compensation power correction signal PC becomes zero.

  Similarly, the compensation power correction signal calculation unit 32 outputs the compensation power correction signal PCp as the compensation power correction signal PC when the stored power amount ES rises and exceeds the stored power amount upper limit threshold EH (EH ′). To start. The compensation power correction signal PCp is a positive signal. Since the compensation power correction unit 16 in the subsequent stage adds the compensation power correction signal PC to the compensation power ΔPG, the compensation compensation power ΔPG ′ is a compensation power correction signal with respect to the compensation power ΔPG. It shifts in the direction of discharging from the power storage device by PCp.

  Thereafter, when the stored power amount ES decreases and falls below the stored power amount upper limit threshold EH (EH ′), the compensation power correction signal calculation unit 32 stops outputting the compensation power correction signal PCp. That is, the compensation power correction signal PC becomes zero.

  By configuring the compensation power correction signal generation unit as shown in FIG. 4, the compensation power correction signal calculation unit has a stored power amount ES within a predetermined range from the stored power amount upper limit value Emax (EH to Emax or EH ′ to Emax), the compensation power correction signal PC is generated in the direction of discharging from the power storage device 5, and the corrected storage power amount ES is within a predetermined range (Emin to EL) from the stored power amount lower limit Emin. Or Emin to EL ′), when the compensation power correction signal PC is generated in the direction of charging the power storage device 5, the stored power amount sticks to the upper and lower limit values in the long term. To prevent.

  By the way, when the output of the distributed power source is within a predetermined range (Pmin to PL) from the output lower limit value Pmin, the threshold value of the stored power amount is exceeded by the threshold value correction signal LC from the threshold value correction signal calculation unit 31. The value EH is corrected in the decreasing direction and becomes EH ′.

  Thus, when the compensation power correction signal PC is generated in the direction of discharging from the power storage device 5, the predetermined range (EH to Emax) for determining whether or not the compensation power correction signal PC can be generated is expanded (EH ′ to Emax, where EH '<EH), and it is easy to make correction in the direction of discharging from the power storage device 5 (early correction start timing, extension of the correction period). Note that even if the output of the distributed power source is within a predetermined range (Pmin to PL) from the output lower limit value Pmin, if the power storage device 5 has a sufficient storage power capacity, the discharge direction is not corrected, so it is unnecessary. No correction is required. As a result, it is possible to secure an available storage power capacity free capacity for absorbing power fluctuations in the rising direction of the distributed power supply, and the power storage device 5 cannot absorb the increasing power fluctuation components, thus making it impossible to compensate for power fluctuations. It is possible to reduce the risk and effectively compensate for the power fluctuation when the distributed power source is started up.

  Similarly, when the output of the distributed power source is within a predetermined range (PH to Pmax) from the output upper limit value Pmax, the stored power amount lower limit is set by the threshold value correction signal LC from the threshold value correction signal calculation unit 31. The threshold value EL is corrected in the increasing direction to become EL ′.

  As a result, when the compensation power correction signal PC is generated in the direction of charging the power storage device 5, the predetermined range (Emin to EL) for determining whether or not the compensation power correction signal PC can be generated is expanded (Emin to EL ′, where EL < EL ′) and correction is likely to be applied in the direction of charging the power storage device (adjustment of the correction start timing and extension of the correction period). Even if the output of the distributed power source is within a predetermined range (PH to Pmax) from the output upper limit value Pmax, the charging direction is not corrected if the power storage device 5 has a sufficient amount of stored power. Will not take. As a result, the amount of stored power required to compensate for power fluctuations in the falling direction of the distributed power supply can be secured, and the power storage device cannot compensate for the decreasing power fluctuation components, thus making it impossible to compensate for power fluctuations. This makes it possible to effectively compensate for power fluctuations when the distributed power supply falls.

  In the threshold correction signal calculation unit 31, the correction start threshold value and the correction end threshold value (low output correction start threshold value Th5) for the output lower limit threshold value PL and the output upper limit threshold value PH, respectively. Low output correction end threshold Th6, high output correction end threshold Th7, high output correction start threshold Th8), low output correction start threshold Th5, low output correction end The threshold value Th6 is set close to the output lower limit value Pmin of the distributed power source, and the high power correction end threshold value Th7 and the high output correction start threshold value Th8 are set close to the output upper limit value Pmax of the distributed power source. As a result, the threshold correction signal LC can be output only when the output of the distributed power source reaches the vicinity of the output lower limit value Pmin or the output upper limit value Pmax. It is possible to prevent an unnecessary correction operation when not force lower-limit value Pmin vicinity or the output upper limit value Pmax vicinity. In addition, since the correction start threshold value and the correction end threshold value are set separately, once the output of the threshold correction signal LC is started, the output of the distributed power source becomes larger (as it reaches the correction end threshold value). As long as it does not fluctuate, the output of the threshold correction signal LC does not stop, and after the output of the threshold correction signal LC stops, the output of the distributed power source increases (approaching the correction start threshold). As long as it does not fluctuate, the output of the threshold value correction signal LC does not resume, so that it is possible to prevent the correction operation by the threshold value correction signal LC from being frequently turned on and off (ON / OFF).

FIG. 5 shows another configuration example for realizing the compensation power correction signal calculation unit. The configuration other than the compensation power correction signal calculation unit is as shown in FIG.
In the compensation power correction signal calculation unit 32A in FIG. 5, when the stored power amount ES is input and the stored power amount ES exceeds a certain reference value TH, a positive compensation power correction signal PC is output, and the stored power amount ES is When the value falls below a certain reference value TH, a negative compensation power correction signal PC is output, and the absolute value of the signal increases as the stored power amount ES departs from the reference value TH.

  However, the reference value TH changes according to the threshold correction signal LC from the threshold correction signal calculation unit 31. That is, when the active power measurement value PG is within a predetermined range (Pmin to PL) from the output lower limit value Pmin of the distributed power source, the reference value TH is decreased by the threshold correction signal LCm and / or effective. When the power measurement value PG is within a predetermined range (PH to Pmax) from the output upper limit value Pmax of the distributed power source, the reference value TH increases by the threshold value correction signal LCp.

  When the compensation power correction signal calculation unit is configured as shown in FIG. 5, the threshold correction signal LC from the threshold correction signal calculation unit 31 has the following effects on the compensation power correction signal calculation unit 32A. .

  When the reference value TH is corrected so as to decrease by the threshold correction signal LCm, the compensation power correction signal PC from the compensation power correction signal calculation unit 32A is compared with the case where the correction is not performed on the reference value TH. Increase). That is, when the output of the distributed power source is within a predetermined range (Pmin to PL) from the output lower limit value Pmin, the compensation power correction signal PC is shifted in the direction of discharging from the power storage device 5, and the compensation power correction is performed. In the part 16, the correction effect is strengthened in the direction of discharging from the power storage device 5. That is, the correction process in which the compensation power correction unit 16 discharges from the power storage device 5 is further promoted. Note that even if the output of the distributed power source is within a predetermined range (Pmin to PL) from the output lower limit value Pmin, if the power storage device 5 has a sufficient storage power capacity, the discharge direction is not corrected, so it is unnecessary. No correction is required. As a result, it is possible to secure an available storage power capacity free capacity for absorbing power fluctuations in the rising direction of the distributed power supply, and the power storage device 5 cannot absorb the increasing power fluctuation components, thus making it impossible to compensate for power fluctuations. It is possible to reduce the risk and effectively compensate for the power fluctuation when the distributed power source is started up.

  Similarly, when the reference value TH is corrected so as to increase by the threshold value correction signal LCp, the compensation power correction signal PC from the compensation power correction signal calculation unit 32A is not corrected with respect to the reference value TH. Decrease). That is, when the output of the distributed power source is within a predetermined range (PH to Pmax) from the output upper limit value Pmax, the compensated power correction signal PC is shifted in the direction of charging the power storage device 5 and compensated power compensation. In the part 16, the correction effect is strengthened in the direction in which the power storage device 5 is charged. In other words, the correction process for charging the power storage device 5 in the compensation power correction unit 16 is further promoted. Even if the output of the distributed power source is within a predetermined range (PH to Pmax) from the output upper limit value Pmax, the charging direction is not corrected if the power storage device 5 has a sufficient amount of stored power. Will not take. As a result, the amount of stored power necessary to compensate for power fluctuations in the falling direction of the distributed power supply can be ensured, and the power storage device 5 cannot fully compensate for the reduced power fluctuation components, thus making it impossible to compensate for power fluctuations. It is possible to effectively compensate for power fluctuations when the distributed power supply falls.

  The effects of the power stabilization system 10 described above will be described with reference to the verification results shown in FIGS. Here, in order to compensate the output fluctuation of the wind power generator, in the power stabilization system 10 using the power storage device 5 having the configuration shown in FIGS. 1 to 3, the stored power amount correction signal calculation unit 21 and the storage The measured waveform when the stored power amount ES is corrected by the power amount correcting unit 22 (hereinafter, “with stored power amount correction control”) is shown. 8, 9, and 10, for the sake of comparison, the stored power amount ES is not corrected by the stored power amount correction signal calculation unit 21 and the stored power amount correction unit 22 (hereinafter referred to as “stored power amount”). The simulation results of “no correction control”) are also shown.

  In addition, since it is difficult to change the configuration in the control device 1 in an actual machine, and even if the configuration is changed, the output of the wind power generation that is the compensation target cannot be reproduced with the wind, so here the stored power amount correction control is not performed. The simulation result is obtained by modeling the power stabilization system using the power storage device 5 and inputting the wind power generation output data measured in the actual machine, that is, by inputting the same data.

  FIG. 6 is a graph showing the active power measurement value PG of the wind power generator (distributed power source) 2. As shown in FIG. 6, the active power measurement value PG of the wind power generator (distributed power source) 2 is close to zero in the vicinity of 0 to 7000 seconds, and then the wind power generator (distributed power source) from about 7000 seconds to about 9000 seconds. ) It can be seen that the active power measurement value PG of 2 is greatly increased.

  FIG. 7 is a graph showing the stored power amount correction signal EC. As shown in FIG. 6, the output of the wind power generator (distributed power source) 2 is close to zero in the vicinity of 0 to 7000 seconds. For this reason, a positive stored power amount correction signal EC is output to correct the stored power amount ES in the increasing direction.

FIG. 8 is a graph showing the stored power amount ES (ES1 in the figure) with the stored power amount correction control and the stored power amount ES (ES2 in the figure) without the stored power amount correction control.
As shown in FIG. 7, when the stored power amount correction control is performed, the output of the wind power generator (distributed power source) 2 is close to zero in the vicinity of 0 to 7000 seconds. , And as a result of correcting the stored power amount ES in the increasing direction, as shown by ES1 in FIG. 8, it can be seen that a sufficient free space for the stored power amount is secured in the vicinity of 0 to 5000 seconds.

FIG. 9 is a graph showing a correction signal PC (PC1 in the figure) when the stored power amount correction control is present and a correction signal PC (PC2 in the figure) when the stored power amount correction control is not present.
As shown in FIG. 7, the stored power amount correction signal EC is output in the vicinity of 0 to 7000 seconds by the stored power amount correction control. As can be seen from ES1 in FIG. 8, in the vicinity of 0 to 5000 seconds, There is sufficient free space in the stored energy ES. For this reason, as indicated by PC1 in FIG. 9, the correction signal PC is not output. That is, even if the stored power amount correction control is performed, an unnecessary correction operation is not performed when there is a vacant capacity (stored power amount) of a sufficient stored power amount.

  Further, as a result of the stored power amount being corrected in the increasing direction by the stored power amount correction control and being easily corrected in the direction in which the stored power amount is discharged in the compensation power correction signal calculation unit 23, as shown by PC1 in FIG. The correction signal PC is output from around 5000 seconds to around 6000 seconds. In other words, it can be seen that the storage power amount correction control operates so as to secure a necessary storage power amount capacity (free capacity).

  On the other hand, when there is no stored power amount correction control, as shown by ES2 in FIG. 8, the free space of the stored power amount is tight around 7000 seconds to 9000 seconds. As a result, as shown in PC2 in FIG. 9, it can be seen that the compensation power correction signal is output, and the operation is performed to ensure the free capacity of the stored power amount.

  FIG. 10 is a graph showing the total value of the active power value PG, which is the output of the wind power generator 2, and the output PS of the power stabilization system, that is, the compensated active power PG + PS. Measured waveform of compensated effective power PG + PS (PG + PS1 in the figure) with stored power amount correction control and compensated effective power PG + PS (PG + PS2 in the figure) without stored power amount correction control ) And the active power measurement value PG (before compensation).

  As shown by PG in FIG. 10, the output of the wind power generator (distributed power source) 2 is close to zero from around 5000 seconds to around 6000 seconds, and the stored power amount is slightly higher than the upper limit value as shown by ES1 in FIG. Therefore, when the stored power amount correction control is present, as a result of controlling the stored power amount to be discharged in advance from around 5000 seconds to around 6000 seconds, the effective power after compensation increases as shown by PG + PS1 in FIG. Can be confirmed. Moreover, since the free space of the stored power amount can be secured by the stored power amount correction control, the fluctuation due to the increase in the output of the wind power generator (distributed power source) 2 from around 7000 seconds to around 9000 seconds can be suppressed. Similarly, it can be seen from PG + PS1 in FIG.

  On the other hand, in the case of no storage power amount correction control, the storage power amount approaches the upper limit as the output of the wind power generator (distributed power source) 2 increases from around 7000 seconds to around 9000 seconds, and the stored power amount approaches the upper limit. Therefore, it is necessary to correct the stored energy. As a result, as shown by PG + PS2 in FIG. 10, it can be seen that fluctuation due to an increase in the output of the wind power generator (distributed power source) 2 from around 7000 seconds to around 9000 seconds cannot be sufficiently suppressed.

  As described above, according to the power stabilization system using the power storage device of this example, the upper and lower limits of the stored power amount or the stored power amount of the compensation power correction signal calculation unit according to the output of the distributed power source. Power at the time of rising (falling) of the distributed power supply by correcting the value and securing the amount of stored power (storage power free space) necessary for power fluctuation compensation at the time of rising (falling) of the distributed power supply It is possible to provide a power stabilization system using a power storage device, a control device thereof, and the like that can effectively compensate for power fluctuations against fluctuations.

It is a lineblock diagram of the power stabilization system concerning this embodiment. It is a 1st structural example of a compensation electric power correction signal generation part. It is another example of a structure of the compensation power correction signal calculating part which comprises the compensation power correction signal generation part of FIG. It is a 2nd structural example of a compensation electric power correction signal generation part. 6 is another configuration example of a compensation power correction signal calculation unit that constitutes the compensation power correction signal generation unit of FIG. 4. It is the graph which showed the active power measurement value of the wind power generator (distributed power supply). It is the graph which showed the stored electric energy correction signal. It is the graph which showed the stored electric energy in the case with storage electric energy correction control, and the case without storage electric energy correction control. It is the graph which showed the compensation electric power correction signal about the case with storage electric energy correction control, and the case without storage electric energy correction control. It is the graph which showed the effective power after compensation.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Control apparatus 2 Wind generator 3 Transformer 4 Electric power system 5 Power storage apparatus 6 Power converter 7 Transformer 10 Power stabilization system 11 Active power detection part 12 Compensation power calculation part 13 Power converter control part 14 Power storage amount detection 15 Compensation power correction signal generation unit 16 Compensation power correction unit

Claims (7)

A power stabilization system connected to an AC power system together with a distributed power source to suppress fluctuations in active power of the distributed power source,
A power storage device for storing power and charging / discharging the AC power system;
Active power detection means for detecting the active power of the distributed power source as an active power measurement value;
A stored power amount detecting means for detecting a stored power amount of the power storage device or a signal corresponding to the stored power amount;
Compensation power calculation means for calculating compensation power based on a fluctuation component of the active power measurement value;
When the stored power amount is within a predetermined range from the stored power amount upper limit value, a compensation power correction signal is generated in a direction of discharging from the power storage device, and the stored power amount is within a predetermined range from the stored power amount lower limit value. A compensation power correction signal generating means for generating a compensation power correction signal in a direction to charge the power storage device,
Compensation power correction means for correcting the compensation power based on the compensation power and the compensation power correction signal and generating corrected compensation power;
Power converter control means for transmitting a power converter output command according to the corrected compensation power;
In accordance with a power converter output command issued from the power converter control means, a power converter that mutually converts charge / discharge power between the power storage device and the AC power system,
The compensation power correction signal generation means includes:
When the active power measurement value is within a predetermined range from the output lower limit value of the distributed power source, the compensation power correction signal is generated so as to promote the correction processing performed in the direction of discharging from the power storage device in the compensation power correction means. And
And / or, when the active power measurement value is within a predetermined range from the output upper limit value of the distributed power source, the compensation power so as to promote correction processing performed in the direction of charging the power storage device in the compensation power correction means. A power stabilization system using a power storage device, characterized by generating a correction signal. The compensation power correction signal generation means includes:
When the active power measurement value is within a predetermined range from the output lower limit value of the distributed power source, a stored power amount correction signal is output in a direction to increase the stored power amount, and / or the active power measurement value is A storage power amount correction signal calculating means for outputting a stored power amount correction signal for reducing the stored power amount when the output power upper limit value is within a predetermined range;
A stored power amount correcting means for correcting the stored power amount based on the stored power amount and the stored power amount correction signal, and generating a corrected stored power amount;
When the corrected stored power amount is within a predetermined range from the upper limit value of the stored power amount of the power storage device, the compensation power correction signal is output in a direction of discharging from the power storage device, and the corrected stored power amount is A compensation power correction signal calculation means for outputting the compensation power correction signal in a direction to charge the power storage device when the power storage device is within a predetermined range from the lower limit value of the stored power amount of the power storage device;
The power stabilization system according to claim 1, comprising: The stored power amount correction signal calculation means includes:
Within the output possible range of the distributed power source, the low output correction start threshold Th1, the low output correction end threshold Th2, the high output correction end threshold Th3, and the high output correction start threshold Th4 is set so that Th1 <Th2 <Th3 <Th4,
When the active power measurement value decreases and falls below the Th1, the output of the stored power amount correction signal is started in the direction of increasing the stored power amount, and then the active power measurement value rises and exceeds the Th2 The output of the stored energy correction signal is stopped,
When the active power measurement value rises and exceeds the Th4, the output of the stored power amount correction signal is started in the direction of decreasing the stored power amount, and then the active power measurement value decreases and falls below the Th3 The power stabilization system according to claim 2, wherein the output of the stored power amount correction signal is stopped. The compensation power correction signal generation means includes:
When the stored power amount exceeds the stored power amount upper limit threshold value EH, the compensation power correction signal is output in the direction of discharging from the power storage device, and the stored power amount falls below the stored power amount lower limit threshold value EL. A compensation power correction signal calculating means for outputting the compensation power correction signal in a direction to charge the power storage device;
When an active power measurement value is within a predetermined range from an output lower limit value of the distributed power source, a threshold correction signal is output in a direction to decrease the stored power amount upper limit threshold value EH, and / or active power A threshold value correction signal calculating means for outputting a threshold value correction signal in a direction to increase the stored power amount lower limit threshold value EL when the measured value is within a predetermined range from the output upper limit value of the distributed power source;
The power stabilization system according to claim 1, comprising: The threshold correction signal calculation means includes:
Among the possible output ranges of the distributed power source, the low output correction start threshold Th5, the low output correction end threshold Th6, the high output correction end threshold Th7, and the high output correction start threshold Th8 is set so that Th5 <Th6 <Th7 <Th8,
When the active power measurement value decreases and falls below Th5, output of the threshold correction signal is started in a direction to decrease the stored power amount upper limit threshold value EH, and then the active power measurement value increases. When the value exceeds Th6, the output of the threshold correction signal is stopped,
When the active power measurement value rises and exceeds the Th8, output of the threshold value correction signal is started in the direction of increasing the stored power amount lower limit threshold EL, and then the active power measurement value decreases. The power stabilization system according to claim 4, wherein the output of the threshold value correction signal is stopped when the value falls below Th7. A control device for controlling charging / discharging of power stored in a power storage device,
Active power detection means for detecting the active power of the distributed power source as an active power measurement value;
A stored power amount detecting means for detecting a stored power amount of the power storage device or a signal corresponding to the stored power amount;
Compensation power calculation means for calculating compensation power based on a fluctuation component of the active power measurement value;
When the stored power amount is within a predetermined range from the stored power amount upper limit value, a compensation power correction signal is generated in a direction of discharging from the power storage device, and the stored power amount is within a predetermined range from the stored power amount lower limit value. A compensation power correction signal generating means for generating a compensation power correction signal in a direction to charge the power storage device,
Compensation power correction means for correcting the compensation power based on the compensation power and the compensation power correction signal to generate a corrected compensation power;
Power converter control means for controlling the conversion operation of the power converter by a power converter output command value corresponding to the corrected compensation power;
With
The compensation power correction signal generation means includes:
When the active power measurement value is within a predetermined range from the output lower limit value of the distributed power source, the compensation power correction signal is generated so as to promote the correction processing performed in the direction of discharging from the power storage device in the compensation power correction means. And
And / or, when the active power measurement value is within a predetermined range from the output upper limit value of the distributed power source, the compensation power so as to promote correction processing performed in the direction of charging the power storage device in the compensation power correction means. A control device that generates a correction signal. A control program used in a control device for controlling charge / discharge of power stored in a power storage device,
When the stored power amount is within a predetermined range from the stored power amount upper limit value, a signal for controlling charging / discharging of the power stored in the power storage device in a direction of discharging from the power storage device is corrected, and the stored power If the amount is within a predetermined range from the stored energy lower limit, correct the signal that controls the charging and discharging of the power stored in the power storage device in the direction of charging the power storage device,
And,
When the active power measurement value is within a predetermined range from the output lower limit value of the distributed power source, a process for promoting correction to be performed in the direction of discharging from the power storage device is executed,
And / or when the active power measurement value is within a predetermined range from the output upper limit value of the distributed power source, a process for promoting correction to be performed in the direction of charging the power storage device is executed.
A control program for causing a computer to execute processing.