JP2017118656A - Energy stabilizer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To house an energy storage amount in a storage device within a reference range, and perform leveling of a power generation on the basis of previous actual data.SOLUTION: An energy stabilizer 1 suppressing variation in power generated by a power generator of a renewable energy connected to an electric power system, comprises: a first energy accumulation device 3 which can accumulate an energy corresponding to a power generated by a power generator 2, and can supply an electric power corresponding to the accumulated energy to an electric power system that is combined to the generated power; a first accumulation monitoring part 4 that monitors the energy accumulation amount of the first energy accumulation device; a leveled generated power monitoring part 5 that monitors a leveled generated power; and an accumulation control part 6 that sets the energy accumulation amount of the first energy accumulation device within a first reference range, and controls a variation value in a predetermined period of the leveled generated power set on the basis of previous actual data to a predetermined value or less on the basis of the energy accumulation amount of the first energy accumulation device monitored by the first accumulation monitoring part and the leveled generated power monitored by the leveled generated power monitoring part.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an energy stabilization device that stably supplies generated power from a power generation device to an electric power system.

  Renewable energy such as wind power generation and solar power generation is expected to be used more and more in the future because it can reduce greenhouse gases such as carbon dioxide, prevent global warming, and there is no problem of radioactive contamination. It has been.

  However, since the amount of power generation generally fluctuates greatly depending on time, the renewable energy is likely to fluctuate greatly in the system voltage and frequency when the renewable energy is connected to the power system.

  For this reason, there has been proposed a technique for suppressing fluctuations in system voltage and frequency by providing an energy storage device for storing renewable energy and increasing or decreasing the energy storage amount of the energy storage device as necessary (patent) Reference 1).

  The above publication describes a power stabilization device that divides the output power of a power generator into a long-period component and a short-cycle component by a filter capable of adjusting a time constant, and stores energy in different power storage devices. .

JP2015-80378A

  When the generated power is used in the power system, it is necessary to monitor the generated power so that the system power in the power system does not fluctuate greatly due to power generation, and suppress sudden fluctuations in the generated power (hereinafter referred to as leveling the generated power). is there.

  In order to level the generated power, it is necessary to increase the amount of discharge from the power storage device when the power level of the generated power decreases, and to increase the amount of power stored in the power storage device when the power level of the generated power increases. However, since the device of the above publication does not monitor the current power storage amount of the power storage device, even if it is attempted to charge or discharge the power storage device for leveling the generated power, depending on the power storage amount of the power storage device. , Charging or discharging may not be possible. Thus, in the apparatus of the above publication, there may be a case where the generated power cannot be leveled.

  The present invention has been made in view of the above-described problems, and can stabilize the energy storage amount of the storage device within the reference range and can level the generated power based on past performance data. A device is provided.

In order to solve the above-described problem, in one aspect of the present invention, an energy stabilization device that suppresses fluctuations in generated power output by a power generator of renewable energy linked to a power system,
A first energy storage device capable of storing energy according to the generated power output from the power generation device, and capable of supplying the power according to the stored energy together with the generated power to the power system;
A first accumulation amount monitoring unit for monitoring an energy accumulation amount of the first energy accumulation device;
A post-leveling generated power monitoring unit for monitoring the leveled generated power in the power system;
The first energy storage device based on the energy storage amount of the first energy storage device monitored by the first storage amount monitoring unit and the post-leveling generated power monitored by the leveled generated power monitoring unit. An accumulation control unit that controls the fluctuation value within a predetermined period of the leveled generated power that is set based on past performance data to be within a first reference range, An energy stabilization device is provided.

  When the energy storage amount of the first energy storage device approaches the upper limit within the first reference range, the accumulation control unit does not cause the fluctuation value of the leveled generated power within the predetermined period to exceed the predetermined value. When the energy stored in the first energy storage device is released to the power system together with the generated power in the range, and the energy storage amount of the first energy storage device approaches the lower limit in the first reference range, The energy stored in the first energy storage device may be increased within a range in which the fluctuation value of the generated power after leveling within the predetermined period does not exceed the predetermined value.

Energy can be stored in accordance with the generated power output from the power generation device, and power in accordance with the stored energy can be supplied to the power system together with the generated power, storing more energy than the first energy storage device. A second energy storage device having a small capacity;
A second accumulation amount monitoring unit for monitoring an energy accumulation amount of the second energy accumulation device,
The accumulation control unit includes an energy accumulation amount of the first energy accumulation device monitored by the first accumulation amount monitoring unit, an energy accumulation amount of the second energy accumulation device monitored by the second accumulation amount monitoring unit, and Based on the power level of the post-leveling generated power monitored by the post-leveling generated power monitoring unit, the energy storage amount of the first energy storage device falls within a first reference range, and after the leveling The fluctuation value of the generated power within a predetermined period may be controlled to a predetermined value or less, and the energy storage amount of the second energy storage device may be controlled.

  The accumulation control unit performs control to accumulate energy in the first energy storage device according to the power of the frequency component less than the first frequency in the generated power output from the power generation device, and the energy is equal to or higher than the first frequency. You may perform control which accumulate | stores the energy according to the electric power of a frequency component in the said 2nd energy storage device.

  The accumulation control unit performs control to accumulate energy in the first energy storage device according to the power of the frequency component less than the first frequency and greater than or equal to the second frequency among the generated power output from the power generation device, You may perform control which accumulate | stores the energy according to the electric power of the frequency component more than the said 1st frequency in a said 2nd energy storage device.

A filter for filtering a power generation state signal according to the generated power output from the power generation device may be provided,
The accumulation control unit includes an energy accumulation amount of the first energy accumulation device monitored by the first accumulation amount monitoring unit, an energy accumulation amount of the second energy accumulation device monitored by the second accumulation amount monitoring unit, and Based on the above, the first frequency and the second frequency may be set by variably controlling a time constant for determining the frequency characteristic of the filter.

  The limit number of energy storage / release in the first energy storage device may be less than the limit number of energy storage / release in the second energy storage device.

  The response speed of energy storage / release in the first energy storage device may be slower than the response speed of energy storage / release in the second energy storage device.

  The first energy storage device may be a chemical battery.

  The second energy storage device may be a flywheel device that converts the generated power of the power generation device into rotational energy and stores it, or a capacitor that stores a charge corresponding to the generated power.

  The first energy storage device and the second energy storage device may be different types of chemical batteries.

  According to the present invention, the energy storage amount of the storage device can be kept within the reference range, and the generated power can be leveled based on past performance data.

The block diagram which shows schematic structure of the energy stabilization apparatus by 1st Embodiment. The graph which shows a mode that the electric power level of system electric power changes according to time. The block diagram which shows schematic structure of the energy stabilization apparatus by 2nd Embodiment. The typical block diagram explaining the principle of a flywheel apparatus. The figure which shows the frequency characteristic of generated electric power. The block diagram which shows schematic structure of the energy stabilization apparatus by 3rd Embodiment.

  Hereinafter, embodiments of the present invention will be described in detail.

(First embodiment)
FIG. 1 is a block diagram showing a schematic configuration of an energy stabilizing device 1 according to the first embodiment. The energy stabilization device 1 of FIG. 1 suppresses fluctuations in the generated power output by the renewable energy power generation device 2 linked to the power system. Hereinafter, an example in which the power generation device 2 is a wind power generation device will be mainly described. In the wind power generator 2, it is known that the generated power varies greatly with time. In the present embodiment, even if the generated power of the power generation device 2 varies greatly with time, the generated power is leveled.

  1 includes a first energy storage device 3, a first storage amount monitoring unit 4, a post-leveling generated power monitoring unit 5, a storage control unit 6, and a first power branching / merging unit. 7.

  The first energy storage device 3 can store energy corresponding to the generated power output from the power generation device 2. The electric power according to the energy stored in the first energy storage device 3 can be supplied to the power system together with the generated power. The first energy storage device 3 is preferably a secondary battery having a large energy storage capacity, such as a lithium ion battery. However, as will be described later, in the present embodiment, the first energy storage device 3 is monitored for the amount of energy stored, and the energy storage and release of the first energy storage device 3 are controlled as necessary. It is not necessary to increase the energy storage capacity of the storage device 3 so much. Thereby, an installation cost can be suppressed.

  In addition, the 1st energy storage device 3 should just be what can perform both energy storage and discharge | release, and the kind in particular is not ask | required. Therefore, chemical batteries such as lithium ion batteries, NAS batteries, and redox flow batteries may be used, and various energy storage devices other than chemical batteries such as large-capacity capacitors may be used.

  The first accumulation amount monitoring unit 4 monitors the energy accumulation amount of the first energy accumulation device 3. The leveled generated power monitoring unit 5 monitors the leveled generated power 20 supplied to the power system. Monitoring by the first accumulation amount monitoring unit 4 and the leveled generated power monitoring unit 5 is performed constantly or periodically.

  The accumulation control unit 6 includes an energy accumulation amount of the first energy accumulation device 3 monitored by the first accumulation amount monitoring unit 4, a power level of the post-leveling generated power 20 monitored by the leveled generated power monitoring unit 5, and Based on the above, the energy storage amount of the first energy storage device 3 falls within the first reference range, and the fluctuation value within the predetermined period of the leveled generated power 20 set based on the past performance data is set to a predetermined value. Control to:

  More specifically, when the energy storage amount of the first energy storage device 3 approaches the upper limit within the first reference range, the storage control unit 6 sets the fluctuation value within the predetermined period of the leveled generated power 20 to a predetermined value. When the energy stored in the first energy storage device 3 is released together with the generated power to the power system within a range not exceeding, the energy storage amount of the first energy storage device 3 approaches the lower limit in the first reference range. The energy stored in the first energy storage device 3 is increased within a range in which the fluctuation value within the predetermined period of the leveled generated power 20 does not exceed the predetermined value.

  The first power branching / merging unit 7 performs power control for storing a part of the generated power 20 after leveling in the first energy storage device 3, and generated power after leveling the energy stored in the first energy storage device 3. And the power control that merges with 20 is performed.

  More specifically, the accumulation control unit 6 includes an output leveling command unit 11, a first output adjustment value calculation unit 12, a first difference generator 13, a second output adjustment value calculation unit 14, and a second difference. And a generator 15.

  The output leveling command unit 11 generates and outputs a first command signal that commands the first energy storage device 3 to store or release energy based on the generated power so that the generated power is leveled.

  The first output adjustment value calculation unit 12 generates and outputs a first output adjustment value corresponding to the post-system level generated power 20 monitored by the post-level generation power monitoring unit 5.

  The first difference generator 13 is a difference between an energy storage amount of the first energy storage device 3 monitored by the first storage amount monitoring unit 4 and a predetermined energy storage target amount of the first energy storage device 3. One difference value is generated and output.

  The second output adjustment value calculation unit 14 generates and outputs a second output adjustment value based on the first output adjustment value and the first difference value.

  The second difference generator 15 performs first energy accumulation based on the first command signal output from the output leveling command unit 11 and the second output adjustment value output from the second output adjustment value calculation unit 14. A second command signal for commanding energy storage or release of the device 3 is generated and output. The first energy storage device 3 stores energy corresponding to the generated power from the power generation device 2 based on the second command signal, or releases the stored energy together with the generated power to the power system.

  FIG. 2 is a graph showing how the power level of the system power changes according to time. The horizontal axis represents time [minutes], and the vertical axis represents the active power [W] of system power. If the generated power fluctuates rapidly, the grid power may fluctuate accordingly. Even if the first energy storage device 3 for storing the generated power is provided as in the present embodiment, there is a time lag between energy storage in the first energy storage device 3 and energy release from the first energy storage device 3. Therefore, some fluctuations in system power are inevitable. Furthermore, if a load (not shown) that uses system power from the power system varies, the system power also varies.

  In the present embodiment, the leveled generated power monitoring unit 5 monitors the leveled generated power 20 constantly or periodically. The accumulation control unit 6 controls the energy accumulation amount of the first energy accumulation device 3 so that the fluctuation rate of the leveled generated power 20 within a predetermined period (for example, 20 minutes) does not exceed 10%, for example. The numerical values of the predetermined period and the fluctuation rate may be arbitrarily adjusted based on past performance data.

  Further, the storage control unit 6 sets the energy storage amount of the first energy storage device 3 so that the energy storage amount of the first energy storage device 3 monitored by the first storage amount monitoring unit 4 falls within the first reference range. Control. The first reference range may also be set based on past performance data. For example, the first reference range is 40 to 60% with respect to the total energy storage capacity of the first energy storage device 3. When the storage control unit 6 uses the first storage amount monitoring unit 4 and finds that the energy storage amount of the first energy storage device 3 is likely to fall below 40%, the energy storage amount of the first energy storage device 3 In order to increase the energy, the energy storage process of the generated power in the first energy storage device 3 is performed. When the amount of energy stored in the first energy storage device 3 is increased, generally, the supplied power is reduced, and the generated power 20 after leveling is reduced. Therefore, when increasing the amount of energy stored in the first energy storage device 3, the storage control unit 6 monitors the leveled generated power 20 using the leveled generated power monitoring unit 5, and generates the leveled power generation. The amount of energy stored in the first energy storage device 3 is controlled so that the fluctuation rate of the power 20 within a predetermined period does not exceed a predetermined value.

  Conversely, when the accumulation control unit 6 uses the first accumulation amount monitoring unit 4 and finds that the energy accumulation amount of the first energy accumulation device 3 is likely to exceed 60%, the accumulation control unit 6 In order to reduce the energy storage amount, the energy release amount of the first energy storage device 3 is increased. Increasing the amount of energy released generally increases the level of generated power 20 after leveling. Therefore, when increasing the amount of energy released from the first energy storage device 3, the storage control unit 6 monitors the post-leveling generated power 20 using the post-leveling generated power monitoring unit 5, and generates post-leveling power generation. The amount of energy stored in the first energy storage device 3 is controlled so that the fluctuation rate of the power 20 within a predetermined period does not exceed a predetermined value.

  As described above, in the first embodiment, the energy accumulation amount of the first energy accumulation device 3 capable of accumulating and releasing energy according to the generated electric power is monitored by the first accumulation amount monitoring unit 4, and the power generation after leveling is performed. The power 20 is monitored by the generated power monitoring unit 5 after leveling, and based on these monitoring results, the energy storage amount of the first energy storage device 3 falls within the first reference range, and the generated power 20 after leveling 20 The fluctuation value within a predetermined period is controlled to be equal to or less than a predetermined value. As a result, there is no problem that the generated power 20 after leveling does not meet the leveling target because energy cannot be stored in the first energy storage unit 3 or energy cannot be released from the first energy storage unit 3. Disappear. That is, according to the present embodiment, since the first energy storage device 3 always has a margin for further energy storage and release, the generated power fluctuates rapidly or the load on the power system fluctuates rapidly. Even so, the generated power 20 after leveling can continue to maintain the leveling target.

(Second Embodiment)
In the second embodiment, a second energy storage device is provided separately from the first energy storage device 3.

  FIG. 3 is a block diagram showing a schematic configuration of the energy stabilizing device 1 according to the second embodiment. In FIG. 3, the same reference numerals are given to components common to FIG. 1, and different points will be mainly described below.

  3 includes a second energy storage device 8, a second accumulation amount monitoring unit 9, and a second power branch / merging unit 10 in addition to the configuration of FIG.

  The second energy storage device 8 can store energy corresponding to the generated power output from the power generation device 2. The electric power corresponding to the energy stored in the second energy storage device 8 can be supplied to the power system together with the generated power. The second energy storage device 8 has a smaller energy storage capacity than the first energy storage device 3.

  The second energy storage device 8 is, for example, a flywheel device 8. The flywheel device 8 converts the generated electric power into mechanical rotational energy and stores it.

  FIG. 4 is a schematic block diagram for explaining the principle of the flywheel device 8. The flywheel device 8 in FIG. 4 includes an inverter 21, a motor / generator 22 connected to the inverter 21, and a flywheel 24 that rotates together with the rotating shaft 23 of the motor / generator 22. The inverter 21 is an AC-AC converter that converts the frequency of the generated power (leveled generated power 20) output from the power generator 2 in order to rotate the flywheel 24 at a high speed. The motor / generator 22 rotates the rotating shaft 23 by the output power of the inverter 21. At this time, the motor / generator 22 functions as a motor. Since the flywheel 24 is connected to the rotating shaft 23, the flywheel 24 also rotates when the rotating shaft 23 rotates. Thereby, generated electric power can be converted into rotational energy of the flywheel 24. The rotational energy of the flywheel 24 can be used as electrical energy for driving the motor / generator 22 via the rotating shaft 23 as necessary. At this time, the motor / generator 22 functions as a generator. The generated power generated by the motor / generator 22 is used as the leveled generated power 20.

  Note that the second energy storage device 8 in FIG. 3 is not necessarily limited to the flywheel device 11. For example, a large-capacity capacitor capable of storing generated power as electric charge may be used. The second energy storage device 8 may be various secondary batteries (chemical batteries). As a typical secondary battery, for example, a lithium ion battery or a redox flow battery can be considered. The second energy storage device 8 may be the same type as the first energy storage device 3 or may be a different type. For example, different types of chemical batteries may be used as the first energy storage device 3 and the second energy storage device 8.

  The second accumulation amount monitoring unit 9 monitors the energy accumulation amount of the second energy accumulation device 8. In the present embodiment, it is assumed that the second energy storage device 8 has a smaller energy storage capacity than the first energy storage device 3, and the second energy storage device 8 is in a fully stored state than the first energy storage device 3. It is easy to become. Therefore, the accumulation control unit 6 controls the energy accumulation amount of the second energy accumulation device 8 using the second accumulation amount monitoring unit 9.

  The second power branch / merging unit 10 performs power control for storing a part of the generated power 20 after leveling in the second energy storage device 8 and generates the energy stored in the second energy storage device 8 after system leveling. Power control for joining the power 20 is performed.

  The accumulation control unit 6 in the energy stabilization device 1 of FIG. 3 includes an output leveling command unit 11 having a function added to the configuration of FIG. 1, a third difference generator 16, and a third output adjustment value calculation. A unit 17, a fourth difference generator 18, and a fifth difference generator 19.

  The output leveling command unit 11 stores energy in the first energy storage device 3 or the second energy storage device 8 for each frequency component included in the generated power based on the generated power so that the generated power is leveled. Alternatively, a command signal that commands release is generated and output.

  The third difference generator 16 is a difference between an energy storage amount of the second energy storage device 8 monitored by the second storage amount monitoring unit 9 and a predetermined energy storage target value of the second energy storage device 8. 2 A difference value is generated and output.

  The third output adjustment value calculation unit 17 generates and outputs a third output adjustment value and a fourth output adjustment value corresponding to the second difference value. The fourth difference generator 19 generates and outputs a third difference value that is a difference between the second command signal for the second energy storage device 8 output from the output leveling command unit 11 and the third output adjustment value. To do. The second energy storage device 8 stores energy corresponding to the generated power based on the third difference value, or releases the stored energy and supplies it to the power system together with the generated power.

  The fifth difference generator 18 generates and outputs a fourth difference value that is a difference between the third command signal for the first energy storage device 3 output from the output leveling command unit 11 and the fourth output adjustment value. To do. Based on the fourth difference value, the first energy storage device 3 stores energy corresponding to the generated power, or releases the stored energy and supplies it to the power system together with the generated power.

  In the present embodiment, the first energy storage device 3 mainly stores energy corresponding to power of a frequency component less than the first frequency (hereinafter, long-period component) out of the generated power output from the power generation device 2. . The first energy storage device 3 may mainly store energy corresponding to power of frequency components less than the first frequency and greater than or equal to the second frequency component, rather than all frequency components less than the first frequency.

  The first energy storage device 3 is, for example, a secondary battery (chemical battery) such as a lithium ion battery or a lead storage battery that can be easily increased in capacity. Thus, since the first energy storage device 3 mainly stores long-period components of the generated power, the first energy storage device 3 is more limited in energy storage / release than the second energy storage device 8. The number of times may be small. For example, the number of times of charging and discharging is limited to about several hundreds for a lithium ion battery, but the above-described first energy storage device 3 assumes that charging and discharging are not frequently performed. A secondary battery in which the number of times of charging / discharging is limited can be used.

  The second energy storage device 8 mainly stores the energy corresponding to the power of the first frequency or higher (hereinafter, short cycle component) among the generated power output from the power generation device 2. As the second energy storage device 8, a flywheel device having excellent responsiveness is used.

  FIG. 5 is a diagram showing the frequency characteristics of the generated power, where the horizontal axis represents the frequency and the vertical axis represents the output signal level of the generated power. In FIG. 5, TF is the first frequency, and TH is the second frequency. The accumulation control unit 6 accumulates energy corresponding to the frequency component equal to or higher than the first frequency TF included in the generated power in the second energy storage device 8, and is less than the first frequency TF included in the generated power and equal to or higher than the second frequency TH. Control is performed to store energy corresponding to the frequency component of the first energy storage device 3.

  More specifically, the storage control unit 6 controls the first frequency TF and the second frequency TH so that the energy storage amount of the second energy storage device 8 falls within a predetermined range equal to or less than the full capacity. The second energy storage device 8 has a smaller energy storage capacity than the first energy storage device 3, but has a higher number of energy storage / release limits than the first energy storage device 3 and is excellent in responsiveness. Therefore, it is desirable to store the energy corresponding to the short cycle component in the generated energy output from the power generator 2 in the second energy storage device 8 as much as possible. Thereby, the frequency | count of accumulation | storage / release of the energy in the 1st energy storage device 3 can be reduced, and the lifetime of the 1st energy storage device 3 can be improved.

  Thus, in 2nd Embodiment, since the 1st energy storage device 3 and the 2nd energy storage device 8 are provided, if the free capacity of the 1st energy storage device 3 decreases, the 2nd energy storage device 8 Energy can be stored. Thereby, it becomes easy to perform control to keep the energy storage amount of the first energy storage device 3 within the first reference range and to make the fluctuation value within the predetermined period of the leveled generated power 20 equal to or less than the predetermined value. Further, the second energy storage device 8 having a small energy storage capacity and excellent responsiveness is used for storing short-period components of the generated power, and the first energy storage device 3 having a large energy storage capacity is used for the generated power. Therefore, the frequency of energy storage / release of the first energy storage device 3 can be suppressed, and the life of the first energy storage device 3 can be extended.

(Third embodiment)
In the third embodiment, a filter is provided inside the accumulation control unit 6.

  FIG. 6 is a block diagram showing a schematic configuration of the energy stabilizing device 1 according to the third embodiment. The energy stabilizing device 1 of FIG. 6 includes a filter 11a inside the output leveling command unit 11, and a time constant setting unit 30 for setting the time constant of the filter 11a inside the accumulation control unit 6. Other than this, it is common to FIG.

Based on the power generation state signal from the power generation device 2, the filter 11 a generates a control signal that allocates the generated power output from the power generation device 2 to the first energy storage device 3 and the second energy storage device 8. The power generation state signal is a signal indicating the power generation amount output from the power generation device 2. The output leveling command unit 11 commands the energy storage in the first energy storage device 3 or the second energy storage device 8 for each frequency component included in the generated power based on the control signal from the filter 11a. Is generated and output.
The filter 11a can be expressed by an equivalent transfer function, and TF and TH in FIG. 5 can be arbitrarily adjusted by controlling the time constant of the transfer function. Therefore, the time constant setting unit 30 in the storage control unit 6 controls the time constant of the transfer function of the filter 11a based on the energy storage amounts of the first energy storage device 3 and the second energy storage device 8, thereby , TF and TH in FIG. 5 are adjusted. Thereby, the accumulation control unit 6 accumulates the energy corresponding to the frequency component equal to or higher than the first frequency TF included in the generated power in the second energy storage device 8, and the second is less than the first frequency TF included in the generated power. Control is performed to store energy in the first energy storage device 3 according to a frequency component equal to or higher than the frequency TH.

  As described above, in the third embodiment, the frequency component of the generated power stored in the first energy storage device 3 and the second energy storage device 8 can be arbitrarily adjusted by providing the filter 11a capable of adjusting the time constant. . Therefore, the time constant of the filter 11a is adjusted by the time constant setting unit 30 according to the energy storage amount of the first energy storage device 3 and the second energy storage device 8 and the power level of the generated power 20 after the leveling. Thus, it is possible to level the generated power while adjusting the energy storage amounts of the first energy storage device 3 and the second energy storage device 8 to appropriate amounts.

  The aspect of the present invention is not limited to the individual embodiments described above, and includes various modifications that can be conceived by those skilled in the art, and the effects of the present invention are not limited to the contents described above. That is, various additions, modifications, and partial deletions can be made without departing from the concept and spirit of the present invention derived from the contents defined in the claims and equivalents thereof.

  DESCRIPTION OF SYMBOLS 1 Energy stabilization apparatus, 2 Electric power generation apparatus, 1st energy storage apparatus, 4th 1st accumulation | storage amount monitoring part, 5 Normalized generation electric power monitoring part, 6 Accumulation control part, 7 1st electric power branching / merging part, 11 outputs Leveling command unit, 11a filter, 12 first output adjustment value calculation unit, 13 first difference generator, 14 second output adjustment value calculation unit, 15 second difference generator, 20 generated power after leveling, 21 inverter, 22 motor / generator, 23 rotating shaft, 24 flywheel, 30 time constant setting unit

Claims (11)

An energy stabilization device that suppresses fluctuations in generated power output by a power generator of renewable energy linked to a power system,
A first energy storage device capable of storing energy according to the generated power output from the power generation device, and capable of supplying the power according to the stored energy together with the generated power to the power system;
A first accumulation amount monitoring unit for monitoring an energy accumulation amount of the first energy accumulation device;
A post-leveling generated power monitoring unit for monitoring the leveled generated power in the power system;
The first energy storage device based on the energy storage amount of the first energy storage device monitored by the first storage amount monitoring unit and the post-leveling generated power monitored by the leveled generated power monitoring unit. An accumulation control unit that controls the fluctuation value within a predetermined period of the leveled generated power that is set based on past performance data to be within a first reference range, An energy stabilization device comprising:   When the energy storage amount of the first energy storage device approaches the upper limit within the first reference range, the accumulation control unit does not cause the fluctuation value of the leveled generated power within the predetermined period to exceed the predetermined value. When the energy stored in the first energy storage device is combined with the generated power and released to the power system in the range, and the energy storage amount of the first energy storage device approaches the lower limit in the first reference range, The energy stabilization device according to claim 1, wherein the energy stored in the first energy storage device is increased within a range in which a fluctuation value of the generated power after leveling within the predetermined period does not exceed the predetermined value. Energy can be stored in accordance with the generated power output from the power generation device, power corresponding to the stored energy can be supplied to the power system in accordance with the generated power, and the energy storage capacity is higher than that of the first energy storage device. A second energy storage device having a small
A second accumulation amount monitoring unit for monitoring an energy accumulation amount of the second energy accumulation device;
The accumulation control unit includes an energy accumulation amount of the first energy accumulation device monitored by the first accumulation amount monitoring unit, an energy accumulation amount of the second energy accumulation device monitored by the second accumulation amount monitoring unit, and Based on the power level of the post-leveling generated power monitored by the post-leveling generated power monitoring unit, the energy storage amount of the first energy storage device falls within a first reference range, and after the leveling The energy stabilization device according to claim 1, wherein a fluctuation value of the generated power within a predetermined period is controlled to be a predetermined value or less, and an energy storage amount of the second energy storage device is controlled.   The accumulation control unit performs control to accumulate energy in the first energy storage device according to the power of the frequency component less than the first frequency in the generated power output from the power generation device, and the energy is equal to or higher than the first frequency. The energy stabilization device according to claim 3, wherein control is performed to store energy corresponding to power of a frequency component in the second energy storage device.   The accumulation control unit performs control to accumulate energy in the first energy storage device according to the power of the frequency component less than the first frequency and greater than or equal to the second frequency among the generated power output from the power generation device, The energy stabilization device according to claim 4, wherein control is performed to store energy in the second energy storage device in accordance with electric power of a frequency component equal to or higher than the first frequency. A filter for filtering a power generation state signal according to the generated power output from the power generator,
The accumulation control unit includes an energy accumulation amount of the first energy accumulation device monitored by the first accumulation amount monitoring unit, an energy accumulation amount of the second energy accumulation device monitored by the second accumulation amount monitoring unit, and 6. The energy stabilization device according to claim 5, wherein the first frequency and the second frequency are set by variably controlling a time constant that determines the frequency characteristic of the filter based on the first frequency.   The energy stability according to any one of claims 3 to 6, wherein a limit number of energy storage / release in the first energy storage device is smaller than a limit number of energy storage / release in the second energy storage device. Device.   The energy stabilization according to any one of claims 3 to 6, wherein a response speed of energy storage / release in the first energy storage device is slower than a response speed of energy storage / release in the second energy storage device. Device.   The energy stabilization device according to any one of claims 1 to 8, wherein the first energy storage device is a chemical battery.   The said 2nd energy storage apparatus is a flywheel apparatus which converts the electric power generated by the said electric power generating apparatus into rotation energy, and accumulate | stores it, or a capacitor which accumulate | stores the electric charge according to the said generated electric power. The energy stabilization device according to item.   The energy stabilization device according to any one of claims 3 to 8, wherein the first energy storage device and the second energy storage device are different types of chemical batteries.

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