JP2012205462A - Control device for power storage system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control device for a power storage system capable of performing an adjustment control of frequencies in a power system without hindering users' purpose of using storage batteries for load equalization.SOLUTION: According to frequency fluctuations of a power system, a calculation part 21 for calculating an adjusting charge/discharge power calculates an adjusting charge/discharge power that constrains frequency fluctuations within a range of a charge/discharge permissible variation width stored in advance in a storage part 20 for storing charge/discharge permissible variation width patterns. An addition operation part 23 adds the adjusting charge/discharge power to charge/discharge power, stored in a base charge/discharge pattern storage part 19 beforehand, that becomes a basis of a charge/discharge of a storage battery 15. A power conditioner 17 performs a charge/discharge control of the storage battery 15 based on a value calculated in the addition operation part 23.

Description

  The present invention relates to a power storage system control device that performs frequency adjustment by charge / discharge control of a storage battery installed in a consumer.

  The frequency adjustment of the power system is performed on the power supplier side, and the frequency is adjusted by automatic frequency control AFC (Automatic Frequency Control) of thermal power generation or pumped-storage power generation. AFC is a control method that compensates for frequency fluctuations caused by imbalance in power supply and demand, and is operated in cooperation with economic load distribution control EDC (Economic Dispatching Control. The frequency of the power system is controlled so as to be kept within a predetermined deviation with respect to the reference frequency by appropriately controlling the output of each generator in accordance with the demand fluctuation of the power system.

  Control of the output of such a generator alone may not be able to cope with demand fluctuations. In recent years, power storage technology is used to store power when demand is low, and to store stored power when demand is high. It is released to respond to demand fluctuations.

  When the frequency deviation of the power system exceeds a predetermined range, the generator responds to demand fluctuations, and when the frequency deviation is less than the predetermined range, the secondary battery power is discharged to the power system, or the power system power Or a secondary battery is charged to eliminate the power supply-demand imbalance and suppress frequency fluctuations in the power system (see Patent Document 1).

Japanese Patent No. 4155664

  However, when the power supply / demand imbalance is performed by charging / discharging the secondary battery, it is necessary to provide a dedicated secondary battery for frequency adjustment, which increases the equipment cost. Since the frequency adjustment power on the power supplier side is insufficient only in a short period (end-of-season) when power demand decreases, it is not economically advantageous to provide a dedicated secondary battery for frequency adjustment.

  Therefore, it is conceivable to adjust and control the frequency of the power system using a storage battery installed at the consumer. The storage battery installed at the consumer is generally intended for load leveling of the consumer, etc. Therefore, the purpose of use of the storage battery must not be harmed.

  The objective of this invention is providing the electrical storage system control apparatus which can adjust-control the frequency of an electric power grid | system without impairing the use purpose of the load leveling of a storage battery of a consumer.

  The power storage system controller according to claim 1 is a base charge / discharge pattern in which a charge / discharge power serving as a charge / discharge base of a storage battery installed in a consumer stores a base charge / discharge pattern set in advance for each time zone. A storage unit, a charge / discharge allowable variation range pattern storage unit that stores a charge / discharge allowable variation range pattern preset for each time zone with respect to the base charge / discharge power, and a power system An adjustment charge / discharge power calculation unit that calculates adjustment charge / discharge power that suppresses fluctuations in the frequency within the range of the charge / discharge allowable fluctuation range according to frequency fluctuations, and a base set in the base charge / discharge pattern An addition calculation unit that adds the adjusted charge / discharge power calculated by the adjusted charge / discharge power calculation unit to the charge / discharge power, and discharge / charge control of the storage battery based on the value calculated by the addition calculation unit Characterized by comprising a power sale power conditioner.

  A power storage system control device according to a second aspect of the invention is characterized in that, in the first aspect of the invention, the charge / discharge allowable fluctuation range is the same as the discharge-side allowable fluctuation width and the charging-side allowable fluctuation width. To do.

  According to invention of Claim 1, according to the fluctuation | variation of the frequency of an electric power grid | system, adjustment charging / discharging electric power is adjusted with the storage battery installed in the consumer within the range of the charging / discharging allowable fluctuation | variation range with respect to charging / discharging electric power used as a base. Since the adjustment is performed, it is possible to suppress frequency fluctuations in the power system without hindering load leveling, which is an original purpose of the storage battery of the customer.

  According to the invention of claim 2, since the allowable fluctuation range on the discharge side and the allowable fluctuation range on the charging side are made the same, even if the frequency fluctuation fluctuates in any direction, the frequency fluctuation is evenly distributed. Suppression can be controlled.

The block block diagram at the time of applying the electrical storage system control apparatus which concerns on embodiment of this invention to the storage battery installed in the consumer. Explanatory drawing of an example of the base charging / discharging pattern in embodiment of this invention. Explanatory drawing of an example of the charging / discharging allowable fluctuation width pattern in embodiment of this invention. Explanatory drawing which shows the calculation content of adjustment electric power (DELTA) P which suppresses the fluctuation | variation of the frequency in the adjustment charging / discharging electric power calculation part in embodiment of this invention. The graph which shows an example of the charging / discharging electric power of the storage battery which changes according to a frequency fluctuation. The graph which shows operation | movement of the charging / discharging control of the storage battery by the electrical storage system control apparatus which concerns on embodiment of this invention.

  Embodiments of the present invention will be described below. FIG. 1 is a block configuration diagram when the power storage system control device according to the embodiment of the present invention is applied to a storage battery installed in a consumer.

  Electric power is supplied from the power system 11 to the bus 13 of the in-house system via the power receiving transformer 12 to the on-site system of the customer. A load 14 of a consumer is connected to the bus 13, and power is supplied to the load 14 from the power system 11 via the power receiving transformer 12. In addition, a storage battery 15 is provided in the customer's in-house system, and the storage battery 15 is connected to the bus 13 via the interconnection transformer 16 and the power conditioner 17.

  The power conditioner 17 performs charge / discharge control of the battery 15 to level the load on the consumer as viewed from the power system 11 side. For example, when the power consumption of the load 14 is large during the daytime, the power is discharged from the storage battery 15, and when the power consumption of the load 14 is small at night, the storage battery 15 is charged. As a result, the load on the consumer can be leveled when viewed from the power system side.

  The power storage system control device 18 performs charge / discharge control of the storage battery 15 so that the frequency of the power system can be adjusted and controlled without harming the purpose of load leveling of the storage battery 15 of the consumer.

  The base charge / discharge pattern storage unit 19 of the power storage system control device 18 stores in advance a base charge / discharge pattern of charge / discharge power serving as a charge / discharge base of the storage battery 15. FIG. 2 is an explanatory diagram of an example of the base charge / discharge pattern. In the base charge / discharge pattern, charge / discharge power serving as a base for charge / discharge of the storage battery 15 is preset for each time zone. In FIG. 2, the discharge power is positive and the charge power is negative. In the following description, it is assumed that discharging power is positive and charging power is negative.

  For example, in the base charge / discharge pattern shown in FIG. 2, the storage battery 15 is charged with 1200 kW from midnight to 4 o'clock, 900 kW at 4:30, 600 kW at 5 o'clock, and 5:30 to 6 o'clock. Charges 300 kW to the storage battery 15. From 6:30 to 8:30, charging / discharging to the storage battery 15 is not performed, from 9:00 to 20:30, 600 kW is discharged, and from 21:00 to 21:30, charging / discharging to the storage battery 15 is not performed. It is a base charging / discharging pattern which charges 1200 kW from 22:00 to 23:30 without performing. Such a base charge / discharge pattern differs depending on the day of the week, holidays such as May, New Year holidays, and the like, and the base charge / discharge pattern storage unit 19 stores the plurality of base charge / discharge patterns.

  The charge / discharge allowable variation width pattern storage unit 20 stores in advance a charge / discharge allowable variation width pattern that defines the charge / discharge allowable variation width with respect to the charge / discharge power serving as the base shown in FIG. FIG. 3 is an explanatory diagram of an example of the charge / discharge allowable fluctuation width pattern. In the charge / discharge allowable fluctuation width pattern, the charge / discharge allowable fluctuation width is preset for each time zone with respect to the base charge / discharge power. Yes.

  For example, the allowable charge / discharge fluctuation range pattern shown in FIG. 3 allows charging / discharging of the storage battery 15 to ± 200 kW from midnight to 4 o'clock, and charging to ± 400 kW from 4:30 to 9:30. Allow discharge. Also, charge / discharge of ± 350 kW is allowed from 9 o'clock to 20:30, charge / discharge of ± 400 kW is allowed from 21:00 to 21:30, and charge / discharge of ± 200 kW is allowed from 22:00 to 23:30 This is an allowable charge / discharge fluctuation pattern. Similar to the base charge / discharge pattern, such charge / discharge allowable variation width patterns are different patterns depending on the day of the week, holidays such as May holidays, New Year's holidays, and the like. The charge / discharge allowable fluctuation width pattern is stored.

  The charge / discharge allowable fluctuation width of the charge / discharge allowable fluctuation width pattern is determined in advance by a contract between each consumer and the power supplier. This is because the storage battery 15 installed for the purpose of load leveling does not necessarily need to be fully charged / discharged during the off-season period. This is because the amount of stored electricity that can contribute to the adjustment control of the system frequency is different.

  FIG. 3 shows a case where the allowable fluctuation width on the discharge side and the allowable fluctuation width on the charging side are the same as the allowable fluctuation width on charging and discharging. It is also possible to determine a permissible fluctuation range different from the permissible fluctuation range. The consumer wants to discharge from the storage battery 15 during the daytime and wants to charge the storage battery 15 at night. For example, the allowable fluctuation range on the discharge side is increased during the daytime, and the allowable fluctuation range on the charging side. Make it smaller. On the other hand, at night, it is conceivable to decrease the allowable fluctuation range on the discharge side and increase the allowable fluctuation range on the charging side.

  Next, the adjusted charge / discharge power calculation unit 21 calculates adjusted charge / discharge power that suppresses fluctuations in the frequency of the power system within the range of allowable charge / discharge fluctuation width. The frequency f of the power system is detected by a frequency detector 22 provided on the bus 13, and the frequency f of the power system detected by the frequency detector 22 is input to the adjusted charge / discharge power calculating unit 21. In addition, the charge / discharge allowable fluctuation width (discharge-side allowable fluctuation width and charge-side allowable fluctuation width) stored in the charge / discharge allowable fluctuation width pattern storage unit 20 is also input to the adjusted charge / discharge power calculation unit 21.

  The adjustment charge / discharge power calculation unit 21 calculates adjustment power for suppressing frequency fluctuations according to the frequency f of the power system detected by the frequency detector 22, and the adjustment power is charged / dischargeable fluctuation width (discharge side). When the value deviates from the allowable fluctuation range of the charging side and the allowable fluctuation range on the charging side, the adjustment power is limited so as to be within the range of the allowable charging / discharging fluctuation range, and is output to the addition calculation unit 23 as the adjusted charging / discharging power.

  FIG. 4 is an explanatory diagram showing the calculation content of the adjustment power ΔP that suppresses frequency fluctuations in the adjustment charge / discharge power calculation unit 21. The adjusted charging / discharging power calculation unit 21 calculates a frequency deviation Δf between the frequency f of the power system detected by the frequency detector 22 and the reference frequency f0, and calculates the adjusted power ΔP according to the frequency deviation Δf. In FIG. 4, when the reference frequency f0 is 50 Hz and the frequency deviation Δf is within a range of ± 0.04 Hz (frequency f is 49.96 Hz to 50.04 Hz), the adjustment power ΔP is 0 and the frequency deviation Δf is ± 0. In the range of .04 Hz to ± 0.12 Hz (frequency f is 49.88 Hz to 49.96 Hz, 50.04 Hz to 50.12 Hz), the adjustment power ΔP is ± 100 kW, and the frequency deviation Δf is ± 0.12 Hz. When the frequency f deviates from 49.88 Hz or less and 50.12 Hz or more, the adjustment power ΔP is ± 400 kW.

  For example, when the frequency deviation Δf is +0.1 Hz (frequency f is +50.1 Hz), the adjustment power ΔP is −100 kW, and when the frequency deviation Δf is −0.1 Hz (frequency f is 49.9 Hz) ΔP is +100 kW. That is, when the frequency f of the power system is greater than the reference frequency f0, the adjustment power ΔP is negative and the storage battery 15 is the adjustment power in the charging direction. On the other hand, when the frequency f of the power system is smaller than the reference frequency f0, the adjustment power ΔP is positive and becomes the adjustment power in the discharge direction for the storage battery 15.

  When the calculated adjustment power ΔP deviates from the charge / discharge allowable fluctuation range (allowable fluctuation range on the discharge side and allowable fluctuation range on the charge side), the adjusted charge / discharge power calculation unit 21 calculates the allowable charge / discharge fluctuation range. A limiter is applied so as to be within the range and output as adjusted charge / discharge power. For example, in the case of the charge / discharge allowable fluctuation range shown in FIG. 3, the charge / discharge allowable fluctuation range is ± 300 kW from 4:30 to 5:00. Therefore, when the adjustment power ΔP is ± 400 kW, the charge / discharge allowable fluctuation range is ± 300 kW. The regulated charge / discharge power is limited.

  Next, the addition calculating unit 23 adds the adjusted charging / discharging power calculated by the adjusting charging / discharging power calculating unit 21 to the charging / discharging power serving as the base stored in the base charging / discharging pattern storage unit 19. The charge / discharge target value is output to the power conditioner 17. The power conditioner 17 performs discharge charge control of the storage battery 15 based on the charge / discharge target value calculated by the addition calculation unit 23.

  FIG. 5 is a graph showing an example of charging / discharging power of a storage battery that changes in accordance with frequency fluctuation, FIG. 5 (a) is a graph of frequency fluctuation, and FIG. 5 (b) is a graph of charging / discharging power of the storage battery. . FIG. 5 shows an example of the change in the charge / discharge power of the storage battery in response to the frequency fluctuation from 10:00 to 11:00. From 10:00 to 11:00, as shown in FIG. Since power is discharge power, the vertical axis is described as discharge power in FIG. Further, since the discharge power of the consumer at that time is 600 kW, the adjusted charge / discharge power calculated by the adjusted charge / discharge power calculation unit 21 in accordance with the frequency fluctuation is as shown in FIG. 5B. It will fluctuate based on 600 kW.

  From 10:00 to 11:00, the frequency f is in the range of 49.88 Hz to 49.96 Hz, or 50.04 Hz to 50.12 Hz, in a time zone other than the vicinity of 10:43 and 10:55. Therefore, the adjustment power calculated by the adjustment charge / discharge power calculation unit 21 is ± 100 kW. Since this adjusted power (± 100 kW) is within the allowable charge / discharge fluctuation range (± 350 kW) from 10:00 to 11:00, this adjusted power (± 100 kW) is added as the adjusted charge / discharge power (± 100 kW). Is output to the unit 23. Thereby, the power conditioner 17 performs discharge control of the storage battery 15 so that adjustment charging / discharging electric power (± 100 kW) is superimposed on the discharging electric power 600 kW.

  On the other hand, in the vicinity of 10:43 and 10:55, since the frequency f exceeds 50.12 Hz, the adjusted power calculated by the adjusted charge / discharge power calculating unit 21 is −400 kW. Since this adjustment power (-400 kW) exceeds the range of allowable charge / discharge fluctuation range (-350 kW) from 10:00 to 11:00, this adjustment power (-400 kW) is limited to -350 kW, and adjustment charge / discharge power (−350 kW) is output to the addition operation unit 23. The power conditioner 17 controls the discharge of the storage battery 15 so that the adjusted charge / discharge power (-350 kW) is superimposed on the discharge power 600 kW.

  FIG. 6 is a graph showing the operation of charge / discharge control of the storage battery by the power storage system control device according to the embodiment of the present invention. It is assumed that the base charge / discharge power is the base discharge power PB1 at time t0. When there is no change in the frequency f, the adjusted charge / discharge power, which is the output of the adjusted charge / discharge power calculation unit 21, is 0, so the power conditioner 17 controls the discharge with the base discharge power PB1. On the other hand, assume that the frequency fluctuates at time t1. When the frequency f becomes larger than the reference frequency f0, the adjusted charge / discharge power calculation unit 21 outputs negative adjusted charge / discharge power, and when the frequency f becomes smaller than the reference frequency f0, the adjusted charge / discharge power calculation unit. 21 outputs positive adjustment charge / discharge power.

  The adjusted charging / discharging power calculated by the adjusting charging / discharging power calculating unit 21 is added to the base discharging power PB1 by the adding calculating unit 23, and the power conditioner 17 takes a value obtained by adding the adjusting charging / discharging power to the base discharging power PB1. The storage battery 15 is subjected to charge / discharge control as the charge / discharge target value. At time t2, when the base charge / discharge power becomes 0, the power conditioner 17 performs charge / discharge control of the storage battery 15 using only the adjusted charge / discharge power due to frequency fluctuation as the charge / discharge target value. Next, when the base charge / discharge power reaches base charge power −PB2 at time t3, the power conditioner 17 charges the storage battery 15 using the value obtained by adding the adjusted charge / discharge power to the base charge power −PB2 as the charge / discharge target value. Discharge control.

  In this way, within the range of the allowable discharge fluctuation range and the allowable charge fluctuation range of the consumer, the adjusted charge / discharge power or the adjusted discharge power that suppresses the fluctuation of the frequency f according to the fluctuation of the frequency f of the power system is obtained in advance. Since the storage battery 15 is charged and discharged with a value obtained by superimposing it on the set charge / discharge pattern, the frequency fluctuation of the power system can be achieved without impairing the purpose of load leveling of the storage battery 15 of the consumer. Can be suppressed.

DESCRIPTION OF SYMBOLS 11 ... Electric power system, 12 ... Power receiving transformer, 13 ... Bus, 14 ... Load, 15 ... Storage battery, 16 ... Interconnection transformer, 17 ... Power conditioner, 18 ... Power storage system controller, 19 ... Base charge / discharge pattern storage , 20 ... Charge / discharge allowable fluctuation width pattern storage unit, 21 ... Adjustment charge / discharge power calculation unit, 22 ... Frequency detector, 23 ... Addition calculation unit

Claims (2)

A base charge / discharge pattern storage unit that stores a base charge / discharge pattern in which a charge / discharge power serving as a charge / discharge base of a storage battery installed in a consumer is preset for each time zone;
A charge / discharge allowable variation width pattern storage unit that stores a charge / discharge allowable variation width pattern in which a charge / discharge allowable variation width is preset for each time zone with respect to the base charge / discharge power;
An adjusted charge / discharge power calculation unit that calculates adjusted charge / discharge power that suppresses fluctuations in the frequency within the range of the charge / discharge allowable fluctuation range according to fluctuations in the frequency of the power system;
An addition calculation unit that adds the adjusted charge / discharge power calculated by the adjusted charge / discharge power calculation unit to the base charge / discharge power set in the base charge / discharge pattern;
A power storage system control device comprising: a power conditioner that performs discharge charge control of the storage battery based on a value calculated by the addition calculation unit.   2. The power storage system control device according to claim 1, wherein the charge / discharge allowable fluctuation range has the same discharge-side allowable fluctuation range and charging-side allowable fluctuation range.

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