JP2009213319A - Output fluctuation suppressor for natural-energy power generator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an output fluctuation suppressor which quickly returns a natural-energy power generator to a state that allows fluctuation suppression control, when it is difficult for a remaining amount of a power storage part to reach the final stage of charge/discharge, and if the remaining amount reaches the final stage of charging/discharging. <P>SOLUTION: A movement average calculation means 11 smoothes an output fluctuation value of a natural energy power generator 2 so as to calculate a system output reference value. A correction value calculation means 24 calculates the correction amount of the system output reference value, from a difference between an energy remaining amount of a power storage part 6 and a remaining-amount reference so as to add corrections to the system output reference value. A discharge final stage corresponding means 25 makes the system output reference value increase, when a discharge final stage is detected by a discharge final stage detection means 12, on the basis of the remaining amount of the power storage part 6, while a charge final stage corresponding means 26 makes the system output reference value reduce, when a charge final stage is detected by a charge final stage detection means 13, on the basis of the remaining amount of the power storage part 6. A converter control device 7 controls the output of a power converter 5, by using the difference between the system output reference value and output of the natural energy power generator as a command value. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an output fluctuation suppressing device for a natural energy power generation apparatus that is connected between a commercial system and a natural energy power generation apparatus and suppresses output fluctuation of the natural energy power generation apparatus.

  In recent years, natural energy power generation devices that use natural energy, such as wind power generation devices and solar power generation devices, have been linked to commercial systems. In general, since the output of a natural energy power generation apparatus is unstable, output power fluctuations are smoothed.

  FIG. 6 is a configuration diagram of a conventional output fluctuation suppressing device. The output fluctuation suppressing device 3 is connected between the commercial system 1 and the natural energy power generation device 2. The active power output from the natural energy power generation device 2 is detected by the power detector 8 a and input to the fluctuation suppression control device 4 of the output fluctuation suppression device 3.

  The moving average calculation means 11 of the fluctuation suppression control device 4 calculates the moving average value by inputting the output signal of the power detector 8a, and the subtractor 15 calculates the difference between the moving average value and the output signal of the power detector 8a. Calculate and output to the converter controller 7. Based on the difference between the moving average value and the output signal of the power detector 8 a, the converter control device 7 converts the power stored in the power storage unit 6 by the power converter 5 and outputs it to the commercial system 1. The power detector 8b detects the active power output from the power converter 5 to the commercial system 1, and is controlled so that the active power of the power converter 5 is equal to the output signal of the fluctuation suppression control device 4. In order to do so, it is input to the converter controller 7.

  As described above, in the conventional output fluctuation suppressing device, the power converter 5 according to the difference between the output change of the natural energy power generation device 2 made slow by the moving average calculation means 11 and the output of the natural energy power generation device 2. To charge and discharge.

  FIG. 7 is a signal waveform diagram of the output fluctuation suppressing device when the output of the natural energy power generation device 2 suddenly decreases. As shown in FIG. 7, if the output of the natural energy power generation device 2 suddenly decreases at the time point t1, the output of the moving average calculation means 11 has a characteristic of following over time. Therefore, the difference between the output of the natural energy power generation device 2 and the output of the moving average calculation means 11, which is the charge / discharge amount by the power converter 5, becomes a positive value (discharge) for a certain period. In the meantime, the output power to the commercial system 1 has a small variation equal to the output of the moving average calculation means 11 and the remaining amount of the power storage unit 6 continues to decrease.

  On the other hand, if the output of the natural energy power generation device 2 suddenly increases at the time t1 as shown in FIG. 8, the output of the natural energy power generation device 2 and the output of the moving average calculation means 11 are the charge / discharge amount by the power converter 5. Is a negative value (charge) for a certain period. In the meantime, the output power to the commercial system 1 has a small fluctuation equal to the output of the moving average calculation means 11, and the remaining amount of the power storage unit 6 continues to increase.

For smoothing output fluctuations to the power system by distributed power sources such as wind power generators and solar power generators, the output of the distributed power source and the amount of power stored in the power storage unit are detected, and the output of the distributed power source is set in advance Correct the moving average value of the period with the output target adjustment value set in advance according to the amount of power storage, set the output target value to the power system side, and when the output of the distributed power source is larger than the output target value, The power storage unit is charged with the surplus, and when it is smaller than the output target value, the shortage is discharged from the power storage unit, and the output to the power system side is controlled to be the output target value. (For example, refer to Patent Document 1).
JP 2002-17044 A

  However, in the conventional output fluctuation suppression device, depending on the output fluctuation of the natural energy power generation device 2 and the setting of the moving average calculation means 11, discharge or charging may continue for a long time. Moreover, since the amount of charging / discharging is biased, the remaining amount of the power storage unit 6 may reach the end of charging / discharging, and fluctuation suppression due to charging / discharging may not be possible.

  Therefore, in Patent Document 1, when the output of the distributed power source is larger than the output target value, the surplus is charged into the power storage unit, and when the output is smaller than the output target value, the shortage is discharged from the power storage unit. Therefore, the output to the power system is controlled so as to become the output target value, but the output target value is adjusted according to the amount of power stored in the power storage unit, so the remaining amount of the power storage unit is at the end of charge / discharge It has not been confirmed whether it has been reached.

  The object of the present invention is to make the remaining amount of the power storage unit difficult to reach the end of charging / discharging, and when it reaches the end of charging / discharging, a natural energy power generation device that can quickly return to a state in which fluctuation suppression control is possible. An output fluctuation suppressing device is obtained.

  An output fluctuation suppressing device for a natural energy power generation apparatus according to the present invention includes a power converter that discharges or charges power in a power storage unit for storing electric power, and a system output by smoothing an output fluctuation value of the natural energy power generation apparatus. A moving average calculating means serving as a reference value, a correction value calculating means for calculating a correction amount of a grid output reference value from a difference between an energy remaining amount and a remaining amount reference of the power storage unit, and an energy remaining amount of the power storage unit Discharge end detection means for detecting the end of discharge from the battery, charge end detection means for detecting the end of charge from the remaining amount of energy of the power storage unit, and system output reference value when the discharge end is detected by the discharge end detection means Discharge end corresponding means for increasing the charge end, charge end corresponding means for decreasing the system output reference value when the end of charge is detected by the end of charge detection means, the system output reference value and the natural energy power generation Characterized by comprising a transducer controller for controlling the output of the power converter a difference output of the location as a command value.

  According to the present invention, it is difficult for the remaining amount of the power storage unit to reach the end of charging / discharging, and when the end of charging / discharging reaches the end of charging / discharging, the natural energy power generation device capable of quickly returning to a state in which fluctuation suppression control is possible. An output fluctuation suppressing device can be obtained.

  FIG. 1 is a configuration diagram of an output fluctuation suppressing device for a natural energy power generation device according to an embodiment of the present invention. A natural energy power generation device 2 such as solar power generation is connected to the commercial system 1. The output fluctuation suppression device 3 is located between the commercial system 1 and the natural energy power generation device 2 and suppresses output fluctuation of the natural energy power generation device 2. The active power output from the natural energy power generation device 2 is detected by the power detector 8 a and input to the output fluctuation suppressing device 3.

  The output fluctuation suppression device 3 includes a fluctuation suppression control device 4, a power converter 5, a power storage unit 6, a converter control device 7, a power detector 8 b, and a remaining amount detector 9. The power storage unit 6 stores power necessary for output fluctuation suppression, and the power storage amount of the power storage unit 6 is detected by the remaining amount detector 9 and input to the fluctuation suppression control device 4. The fluctuation suppression control device 4 outputs a command for suppressing the output fluctuation to the converter control device 7 based on the output signal of the power detector 8a and the output signal of the remaining amount detector 9. The power detector 8b detects power input / output from the power converter 5, and the converter control device 7 converts power based on the output signal of the power detector 8b and the output signal of the fluctuation suppression control device 4. The device 5 is controlled to output the power stored in the power storage unit 6 to the commercial system 1.

  Moreover, the moving average calculating means 11 of the fluctuation suppression control device 4 receives the output signal of the power detector 8a, calculates a moving average value, and outputs it to the adder 18a as a system output reference value. The correction value calculation means 24 calculates the correction value of the system output reference value based on the output signal of the remaining amount detector 9, and subtracts the difference between the output signal of the remaining amount detector 9 and the remaining amount reference value Rref. When the difference deviates from the set value range of the dead zone 16, the signal corresponding to the deviation is output to the multiplier 17, and the multiplier 17 uses the coefficient set in the constant setting means 14. Is output to the adder 18a as a correction signal.

  The discharge end detection means 12 receives the output signal of the remaining amount detector 9 and detects that the power stored in the power storage unit 6 is the end of discharge. The end-of-discharge detection means 12 includes level detectors 22a and 22b for determining whether or not the output signal of the remaining amount detector 9 is at the end-of-discharge level, and a level detector 22a that detects the end-of-discharge level. The flip-flop 23a uses the output signal as a set signal and the output signal from the level detector 22b that detects that the end-of-discharge level has been recovered as a reset signal.

  The end-of-charge detection means 13 receives the output signal of the remaining amount detector 9 and detects that the stored power in the power storage unit 6 is at the end of charge. The end-of-charge detection means 13 includes level detectors 22c and 22d for determining whether or not the output signal of the remaining amount detector 9 is at the end-of-charge level, and a level detector 22c for detecting the end-of-charge level. The output signal is a set signal, and a flip-flop 23b that uses the output signal of the level detector 22d that detects that the end-of-charge level has been recovered as a reset signal.

  The constant setting unit 14 sets the dead zone set value of the dead zone 16 of the correction value calculation unit 24 and the coefficient of the multiplier 17 based on the output signal of the end of discharge detection unit 12 and the output signal of the end of charge detection unit 13. is there.

  The discharge end handling unit 25 includes a selection circuit 19a that selects either the output signal of the adder 18a or the output signal of 0 based on the output signal of the discharge end detection unit 12, and the increasing rate of change of the system output reference value And an increase-side change rate limiting means 20 that limits the difference between the output signal of the increase-side change rate limiting means 20 and the output signal of the adder 18a. The selection circuit 19a selects an output signal of 0 when the discharge end level is reached.

  The end-of-charge handling means 26 includes a selection circuit 19b that selects either the output signal of the adder 18a or the discharge set value Pdis based on the output signal of the end-of-charge detection means 13, and a rate of change on the decrease side of the system output reference value. Decrease side change rate limiting means 21, and a subtractor 15c for calculating the difference between the output signal of the decrease side change rate limiting means 21 and the output signal of the adder 18a. The selection circuit 19b selects the output signal of the discharge set value Pdis when it is at the end-of-charge level.

  The adder 18b adds the output signal of the adder 18a, the output signal of the subtractor 15b, and the output signal of the subtractor 15c, and subtracts the difference between the output signal of the adder 18b and the output signal of the power detector 8a. And output to the converter controller 7.

  Next, the operation of the normal output fluctuation suppressing device 3 will be described. First, in the correction value calculation unit 24, the difference between the output of the remaining amount detector 9 indicating the remaining amount of the power storage unit 6 and the remaining amount reference value Rref is within the range of the dead band set value set by the constant setting unit 14. If there is, the output of the dead zone 16 becomes zero. As a result, the output of the multiplier 17 is also zero, and the correction value from the correction value calculation means 24 is zero. Therefore, the output of the moving average calculation means 11 becomes the output of the adder 18a.

  At this time, the remaining amount of the power storage unit 6 has not reached the end-of-discharge level Rmin, and the output of the level detector 22a is “0”, so the output of the flip-flop 23a, that is, the output of the end-of-discharge detecting means 12 is It is “0” and the output of the adder 18 a is input to the increasing side change rate limiting means 20. Further, the remaining amount of the power storage unit 6 has not reached the end-of-charge level Rmax, and the output of the level detector 22c is “0”, so the output of the flip-flop 23b, that is, the output of the end-of-charge detecting means 13 is “0”. The output of the adder 18a is also input to the decrease side change rate limiting means 21.

  The output of the increase-side change rate limiting means 20 is monotonically increasing when the input signal exceeds the preset change rate on the increase side, and is equal to the input signal when the input signal is below. Similarly, the output of the decrease-side change rate limiting means 21 is monotonically decreased when the input signal exceeds the preset change rate on the decrease side, and is equal to the input signal when the input signal is below.

  In the moving average calculation means 11, the effective power output value of the natural energy power generation device 2 detected by the power detector 8 a is less than or equal to a change rate preset in the increase-side change rate limiting means 20 and the decrease-side change rate limiting means 21. Since the output is slowed down, the outputs of the increase-side change rate limiting means 20 and the decrease-side change rate limiting means 21 are equal to the outputs of the adder 18a. Accordingly, both the output of the subtractor 15b that subtracts the output of the adder 18a from the output of the increase side change rate limiting means 20 and the output of the subtractor 15c that subtracts the output of the adder 18a from the output of the decrease side change rate limiting means 21 are zero. .

  As a result, the output of the adder 18b is equal to the output of the adder 18a and equal to the output of the moving average calculation means 11. The output of the adder 18b is used as a reference value (system output reference value) for the active power to be output to the commercial system, and the subtractor 15d subtracts the output of the power detector 8a from the output of the adder 18b to obtain the effective power of the power converter 5. The command value is input to the converter control device 7 and the power of the power converter 5 is controlled according to the active power command value. Therefore, the power to the commercial system is equivalent to the output signal of the moving average calculating means 11, Steep output fluctuations are suppressed.

  Next, an example of the operation when the remaining power of the power storage unit 6 increases but the system output reference value is increased by the correction value calculation unit 24 will be described with reference to FIG. Now, assuming that the output of the natural energy power generation device 2 suddenly increases at the time t1, the output of the moving average calculation means 11 has a characteristic of following over time.

  The output of the dead zone 16 of the correction value calculation means 24 is a positive value proportional to the difference between the output of the remaining amount detector 9 and the remaining amount reference value Rref, and the output of the multiplier 17 is always positive with the output of the dead zone 16. It is a positive numerical value that is a product of the output of the constant setting means 14 that is a numerical value of.

  The output of the adder 18a is the sum of the output of the moving average calculating means 11 and the output of the multiplier 17, and increases from the output of the moving average calculating means 11. Since the power storage unit 6 has not reached the end of charge or discharge, the output signals of the discharge end detection means 12 and the charge end detection means 13 are “0”, and the outputs of the selection circuits 19a and 19b are the outputs of the adder 18a. Become.

  Since the output of the adder 18a is increased, the output of the decrease side change rate limiting means 21 is equal to that of the adder 18a, and the output of the subtractor 15c is 0. When the output of the adder 18a is lower than the change rate set value, the output of the increasing side change rate limiting means 20 is also equal to the adder 18a, and the output of the subtractor 15b is 0. As a result, the output of the adder 18b, which is the system output reference value, is equal to that of the adder 18a and is larger than the output of the moving average calculation means 11. The increase in the system output accelerates the decrease in the amount of charge by the power converter 5 from time t2, and discharges from time t3 to act so that the remaining amount of the power storage unit 6 approaches the remaining amount reference value Rref. .

  When the change rate of the output of the adder 18a is higher than the change rate set value, the output of the increase-side change rate limiting means 20 is monotonically increased due to a lower change rate set value than the adder 18a. The output of the device 15b is a negative value corresponding to the excess of the change rate. As a result, the output of the adder 18b becomes a system output reference value that does not exceed the change rate set value, and thus acts to suppress the output power to the commercial system 1 to a constant change rate.

  Next, an example of the operation when the remaining power of the power storage unit 6 is reduced but the system output reference value is decreased by the correction value calculation means 24 will be described with reference to FIG. Assuming that the output of the natural energy power generation device 2 suddenly decreases at the time point t1, the output of the moving average calculation means 11 has a characteristic of following over time.

  The output of the dead zone 16 of the correction value calculation means 24 is a negative value proportional to the difference between the output of the remaining amount detector 9 and the remaining amount reference value Rref, and the output of the multiplier 17 is always positive with the output of the dead zone 16. This is a negative numerical value that is a product of the output of the constant setting means 14 that is a numerical value of.

  The output of the adder 18a is the sum of the moving average calculation means 11 and the multiplier 17, and is smaller than the output of the moving average calculation means 11. Since the end of charge and the end of discharge have not been reached, the output signals of the discharge end detection means 12 and the end of charge detection means 13 are “0”, and the outputs of the selection circuits 19a and 19b become the output of the adder 18a. Since the output of the adder 18a is decreased, the output of the increasing side change rate limiting means 20 is equal to that of the adder 18a, and the output of the subtractor 15c is 0. When the output of the adder 18a is lower than the change rate set value, the output of the decreasing side change rate limiting means 21 is also equal to the adder 18a, and the output of the subtractor 15b is 0. As a result, the output of the adder 18b, which is the system output reference value, is equal to that of the adder 18a and is smaller than the output of the moving average calculation means 11. As the system output decreases, the decrease in discharge by the power converter 5 is accelerated from time t2, and charging starts from time t3 so that the remaining amount of the power storage unit 6 approaches the remaining amount reference value Rref.

  When the change rate of the output of the adder 18a is higher than the change rate set value, the output of the decrease side change rate limiting means 21 is monotonously decreased due to the change rate set value lower than that of the adder 18a. The output of the device 15c is a positive value corresponding to the excess of the change rate. As a result, the output of the adder 18b becomes a grid output reference value that does not exceed the change rate set value, and thus acts to suppress the output power to the grid at a constant rate of change.

  Next, an example of the operation when the end of charging is reached will be described with reference to FIG. Now, assuming that the output of the natural energy power generation device 2 suddenly increases at the time t1, the output of the moving average calculation means 11 has a characteristic of following over time. Further, when the remaining amount of the power storage unit 6 increases, the dead zone is exceeded at time t2, the output of the dead zone 16 becomes a positive value, and the output of the dead zone 16 is multiplied by the output of the constant setting means 14. The outputs (system output reference values) of the adders 18 a and 18 b are increased from the output of the moving average calculation means 11.

  If the increase is not sufficient, the state of the output of the natural energy power generation device 2 is greater than the system output after time t2, that is, the state of charge continues, so the remaining amount of the power storage unit increases and reaches the end of charging at time t3. When the end of charge is reached and the output of the end of charge detecting means 13 becomes “1”, the input of the decreasing side change rate limiting means 21 is switched from the output of the adder 18a to the discharge set value Pdis by the selection circuit 19b. The discharge set value Pdis is obtained by multiplying the rated output of the natural energy power generation device 2 by a coefficient exceeding 1.0 (for example, 1.2), and the output of the decrease-side change rate limiting means 21 is instantaneous when the selection circuit 19b is switched. Becomes the discharge set value Pdis.

  At this time, since the output of the subtractor 15b is 0, the output of the adder 18b becomes the output of the decreasing side change rate limiting means 21 (output of the adder 18b = output of the adder 18a + decreasing side change rate limiting means 21). Output-output of adder 18a). The output of the adder 18b, which is the grid output reference value, rapidly increases at time t3, and the grid output reference value is in a discharge state exceeding the output of the natural energy power generation device 2, so the remaining amount of the power storage unit 6 starts to decrease.

  Then, at the time t4 when the remaining amount of the power storage unit 6 reaches the return reference Rmid (for example, the middle point of the charge / discharge amount), the charge end detection means 13 is reset and the output becomes “0”, and the output of the selection circuit 19b is The output is switched to the output of the adder 18a. The output of the decrease-side change rate limiting means 21 monotonously decreases in accordance with the change rate set value, and has the same effect as when the charge / discharge end is not reached after time t5 when it becomes equal to the output of the adder 18a.

  Next, an example of the operation when the end of discharge is reached will be described with reference to FIG. Assuming that the output of the natural energy power generation device 2 suddenly decreases at the time point t1, the output of the moving average calculation means 11 has a characteristic of following over time. As a result, when the remaining amount of the power storage unit 6 decreases, the dead zone is exceeded at time t2 and the output of the dead zone 16 becomes a negative value, and the output of the dead zone 16 is multiplied by the output of the constant setting means 14. Therefore, the outputs (system output reference values) of the adders 18a and 18b are smaller than the output of the moving average calculating means 11.

  If the decrease is not enough, the output of the natural energy power generation device 2 is smaller than the system output after time t2, that is, the discharge state continues, so the remaining amount of the power storage unit 6 decreases and reaches the end of discharge at time t3. . When the end of discharge is reached and the output of the discharge end detection means 12 becomes “1”, the input of the increase side change rate limiting means 20 is switched from the output of the adder 18a to 0 by the selection circuit 19a, and the increase side change rate limiting means 20 The output immediately becomes zero. At this time, since the output of the subtracter 15c is 0, the output of the adder 18b becomes the output of the increasing side change rate limiting means 20 (output of the adder 18b = output of the adder 18a + increasing change rate limiting means 20). Output-output of adder 18a). The output of the adder 18b, which is the grid output reference value, suddenly decreases at time t3, and the grid output reference value is in a charging state that is lower than the output of the natural energy power generation device 2, so the remaining amount of the power storage unit 6 starts to increase.

  At the time t4 when the remaining amount of the power storage unit 6 reaches the return reference Rmid (for example, the middle point of the charge / discharge amount), the discharge end detection means 12 is reset and the output becomes “0”, and the output of the selection circuit 19a is The output is switched to the output of the adder 18a. The output of the increase-side change rate limiting means 20 monotonously increases in accordance with the change rate set value, and has the same effect as when the charge / discharge end is not reached after time t5 when it becomes equal to the output of the adder 18a.

  Next, the operation of the constant setting unit 14 will be described. In the constant setting means 14, an initial setting value of the dead zone 16 and an initial value of the coefficient for the multiplier 17, a change range of the dead zone setting value, a change range of the coefficient for the multiplier 17, and a maximum value of the coefficient are set. In the process of controlling using the initial setting value, the constant setting unit 14 sets the coefficient for the multiplier 17 by the amount of change every time one of the outputs of the discharge end detection unit 12 or the charge end detection unit 13 becomes “1”. Increase it.

  When the maximum value of the coefficient is reached, the dead band set value is decreased by the change width, and the coefficient for the multiplier 17 is returned to the initial value. As described above, the coefficient for the multiplier 17 increases every time the end of charge / discharge is reached, so that the correction amount of the system output reference value corresponding to the remaining amount of the power storage unit 6 increases and the coefficient reaches the maximum value Since the correction amount is further increased by decreasing the dead zone setting value, the remaining amount of the power storage unit 6 is less likely to reach the end of charge / discharge.

  According to the embodiment of the present invention, the output fluctuation of the natural energy power generation device 2 can be suppressed by charging / discharging the excess or deficiency with the power converter 5 using the output of the moving average calculation means 11 as the system output reference value, By correcting the grid output reference value according to the remaining amount of the power storage unit 6, it operates so as to be discharged when the remaining amount is increased, and to be charged when the remaining amount is decreased. It is possible to reduce the frequency of being out of control.

  Moreover, it can recover | recover from the end of charging / discharging by setting it as the system | strain output reference value which switches to charge when it reaches the end of charge, and switches to charge when it reaches the end of discharge. Furthermore, by changing the dead zone setting value and coefficient related to the correction of the system output reference value by the constant setting means 14 every time the charge / discharge end is reached, it is possible to automatically adjust to a control constant that does not easily reach the end of charge / discharge. .

The block diagram of the output fluctuation suppression apparatus of the natural energy power generation apparatus concerning embodiment of this invention. The signal waveform diagram which shows an example of operation | movement in case a system | strain output reference value increases by the correction value calculating means in embodiment of this invention. The signal waveform diagram which shows an example of operation | movement in case a system | strain output reference value reduces by the correction value calculating means in embodiment of this invention. The signal waveform diagram which shows an example of operation | movement when the electric power storage part in embodiment of this invention has reached the end of charge. The signal waveform diagram which shows an example of operation | movement when the electric power storage part in embodiment of this invention reaches the end of discharge. The block diagram of the conventional output fluctuation suppression apparatus. The signal waveform diagram of the conventional output fluctuation suppression apparatus when the output of a natural energy power generation device falls rapidly. The signal waveform diagram of the conventional output fluctuation suppression apparatus when the output of a natural energy power generation device increases rapidly.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Commercial system, 2 ... Natural energy power generation device, 3 ... Output fluctuation suppression apparatus, 4 ... Fluctuation suppression control apparatus, 5 ... Power converter, 6 ... Electric power storage part, 7 ... Converter control apparatus, 8 ... Electric power detector , 9 ... Remaining amount detection means, 11 ... Moving average calculation means, 12 ... Discharge end detection means, 13 ... End of charge detection means, 14 ... Constant setting means, 15 ... Subtractor, 16 ... Dead band, 17 ... Multiplier, 18 DESCRIPTION OF SYMBOLS ... Adder, 19 ... Selection circuit, 20 ... Increase side change rate limiting means, 21 ... Decrease side change rate limiting means, 22 ... Level detector, 23 ... Flip-flop, 24 ... Correction value calculation means, 25 ... Corresponding to discharge end Means, 26...

Claims (2)

  A power converter that discharges or charges the power of the power storage unit for storing power, a moving average calculation means that smoothes the output fluctuation value of the natural energy power generation device and sets it as a system output reference value, and the power storage unit A correction value calculating means for calculating a correction amount of the system output reference value from the difference between the remaining energy level and the remaining capacity reference and correcting the system output reference value, and a discharge for detecting the end of discharge from the remaining energy of the power storage unit End-of-charge detection means, end-of-charge detection means for detecting end-of-charge from the remaining energy of the power storage unit, and end-of-discharge response means for increasing a system output reference value when the end of discharge is detected by the end of discharge detection means And charging end corresponding means for reducing the grid output reference value when the charging end is detected by the charging end detection means, and the difference between the grid output reference value and the output of the natural energy power generation device as a command value. Output fluctuation suppressing device of natural energy power generation device being characterized in that a converter controller for controlling the output of the power converter.   When a discharge end is detected by the discharge end detection means, or when a charge end is detected by the charge end detection means, a constant used for calculation so that the correction value calculated by the correction value calculation means increases. The output fluctuation suppressing device for a natural energy power generator according to claim 1, further comprising constant setting means for changing.

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