JP2013168010A - Power control system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the income and expenditure of a business operator providing an ancillary service using a storage battery.SOLUTION: A control device 20 controls charging and discharging of a storage battery 10 capable of charging from a power system 50 and discharging to the power system 50. The storage battery 10 provides an ancillary service for the power system 50 at cost. The ancillary service is traded on the market per time zone. The control device 20 refers to the histories of prices of provision of the ancillary service on the market to determine a time zone to be bid.

Description

  The present invention relates to a power control system that controls charging and discharging of a storage battery.

  In recent years, generators owned by companies other than major power companies and generators based on natural energy (such as solar power and wind power) are increasingly connected to the power grid for power transmission and distribution. Many of the power generated by these generators is of low quality, and ancillary services are becoming important. Ancillary service refers to a service that maintains power quality such as frequency stabilization of power transmitted and distributed by the power system. Hereinafter, in this specification, the frequency maintenance service is taken up as a representative example of the ancillary service. The ancillary service includes a reactive power supply service for maintaining the voltage.

  The power transmitted and distributed has the property that the frequency decreases instantaneously when the demand exceeds the supply, and the frequency increases instantaneously when the supply exceeds the demand. Therefore, it is conceivable to adjust the output so that the power generation output is increased when the frequency is decreased and the power generation output is decreased when the frequency is increased.

  As a method for adjusting the output, it is conceivable to change the rotational speed of the gas turbine of the thermal power plant. This method can change the power generation output in a few minutes to 10 minutes. As a method capable of adjusting the power supply in a shorter time than this method, a method of connecting a storage battery to the power system and charging / discharging between the power system and the storage battery can be considered. In this method, a storage battery operation management entity charges or discharges from the power system to the storage battery according to a power supply instruction or a power reception instruction from the power system operation management entity.

JP 2007-236085 A

  The storage battery is required to be used within an appropriate range of SOC (State Of Charge) from the viewpoint of life. The same applies when the storage battery is used for ancillary service. The SOC is an index indicating the ratio of the remaining capacity to the full charge capacity.

  By the way, there are cases where ancillary services are implemented exclusively by electric power companies like Japan, but there are also cases where many ancillary service providers such as PJM (Pennsylvania New Jersey Maryland) in the United States do so. is there. In PJM, ancillary services are marketed and ancillary service providers obtain ancillary services and provide ancillary services. That is, many ancillary service providers purchase an accumulator and provide an ancillary service as a business.

  This invention is made | formed in view of such a condition, The objective is to provide the technique which improves the balance of the provider who provides the ancillary service using a storage battery.

  In order to solve the above problems, a power control system according to an aspect of the present invention includes a storage battery that can be charged and discharged from the power system to the power system, and a control device that controls charging and discharging of the storage battery. The storage battery provides ancillary services for the electric power system for a fee, the ancillary services are marketed on a time zone basis, and the control device refers to the consideration history of the ancillary service provision in the market and should be bid To decide.

  Another aspect of the present invention is also a power control system. The electric power control system includes an electric battery including at least one of a storage battery that can be charged and discharged from the electric power system, a load that can consume electric power of the electric power system, and a generator that can supply electric power to the electric power system. And a control device for controlling the facility and the storage battery. Storage batteries and electrical equipment provide ancillary services for the electric power system for a fee, and ancillary services are marketed on a time zone basis, and the combination of storage batteries and electrical equipment participates in market transactions as a single bidder. Decides when to bid by referring to the history of consideration for providing ancillary services in the market.

  According to the present invention, there is provided a technique for improving the balance of a business providing an ancillary service using a storage battery.

It is a figure which shows the whole structure of an electric power supply system. It is a figure for demonstrating a power control system. 2 is a diagram illustrating a configuration of a control device according to Embodiment 1. FIG. FIGS. 4A to 4E are diagrams showing five modes in the case where power is supplied to a power system using a storage battery and electrical equipment in response to a power supply instruction. It is a figure which shows the relationship between SOC of a storage battery, and the electric power feeding form at the time of supplying electric power to an electric power grid | system using a storage battery and an electrical installation. FIGS. 6A to 6E are diagrams showing five forms in the case of receiving power from the power system using a storage battery and electrical equipment in response to a power receiving instruction. It is a figure which shows the relationship between SOC of a storage battery, and the receiving form at the time of receiving electric power from an electric power grid | system using a storage battery and an electrical installation. 4 is a flowchart for explaining an example of power control by the control device according to the first embodiment. FIG. 6 is a diagram illustrating a configuration of a control device according to a second embodiment. It is a figure which shows transition of the service price of a monthly unit. It is a figure which shows transition of the service price of a time unit. It is a figure for demonstrating the score provision to a unit adjustment power supply. It is a figure for demonstrating the calculation example 1 of the discount present value of the storage battery after five years. It is a figure for demonstrating the calculation example 2 of the discount present value of the storage battery after five years. 10 is a flowchart for explaining an operation example of the control device according to the second embodiment. FIG. 10 is a diagram illustrating a configuration of a control device according to a third embodiment. It is a figure which shows the example of a simulation of SOC transition of a storage battery. 12 is a flowchart for explaining an example of processing for determining a time zone for skipping a bid by the control device according to the third embodiment. It is a figure for demonstrating the electric power control system which concerns on a modification.

  FIG. 1 is a diagram illustrating an overall configuration of a power supply system 500. The power supply system 500 is configured such that a plurality of power plants 30, a plurality of power control systems 100, a plurality of consumers 40, and a system operation device 200 are connected to the power system 50. In this specification, in order to simplify the description, the power transmission system and the distribution system are not distinguished from each other and are collectively referred to as a power system 50.

  There are various forms of operation of the power supply system 500. In Japan, the entire power supply system 500 is basically managed by a local monopoly electric power company, and retailing of electric power by non-electric power companies is not permitted (as of January 2012). Each local power company is responsible for supplying power to the local customers 40. In addition, Japanese electric power companies supply high-quality and stable power to consumers 40 by implementing frequency control services (also referred to as frequency adjustment services).

  On the other hand, there are countries and regions where retailing of electricity is liberalized. Typical examples include PJM (Pennsylvania New Jersey Maryland), California, Nord Pool, EDF, Germany, and the like. In these countries and regions, a wholesale power exchange (PX), an independent system operator (ISO), a regional transmission organization (RTO), and the like are established. In general, a power system centered on a transmission line is owned by an electric power company and is operated by ISO or RTO. For example, in PJM, an installed capacity market, a wholesale power market, a frequency adjustment market, and a financial power transmission rights market are established.

  This document focuses on the frequency adjustment market. The frequency adjustment market is a market in which system operators procure regulated power sources that are used for system stable operation from market participants. Specifically, it is a market for procuring a power supply for adjusting a short deviation and a power supply for securing a quick reserve. The power supply for short deviation adjustment is a power supply for coping with a short time load fluctuation in normal times. The instantaneous reserve power is a power source for responding to an emergency such as an accident. In this specification, attention is focused on the short deviation adjustment. Hereinafter, unless otherwise specified, the frequency adjustment market means the short deviation adjustment market.

  The power plant 30 connected to the power system 50 includes various types of power plants such as thermal power, nuclear power, hydropower, wind power, and sunlight. The energy sources of thermal power plants are mainly coal, gas and oil. In some cases, such as Japan, many of the main power plants are owned by local monopoly power companies. In addition to power companies like PJM, many independent power producers (IPP) generate power. In some cases, the locations are distributed and owned.

  The grid operation apparatus 200 is an apparatus managed by an electric power company, ISO, or RTO. The grid operation device 200 detects a load fluctuation (that is, a fluctuation in demand for power) of the power system 50 and gives an instruction to maintain the supply and demand balance of the entire power system 50 to at least one of the power plant 30 and the power control system 100. give. As described above, the grid frequency fluctuates when the supply-demand balance is lost. If the difference between the system frequency and the reference frequency exceeds ± 0.2 Hz, there is a possibility that some devices on the consumer 40 side will be adversely affected. In addition, when the difference between the system frequency and the reference frequency reaches several percent, there is a possibility that problems such as turbine blade resonance and generator shaft twist may occur in the generator.

  The grid operation apparatus 200 can instruct the power plant 30 via the communication network to adjust the power generation output according to the load fluctuation. Specifically, the power generation output is instructed to increase when the power demand exceeds the power supply, and the power generation output is instructed to decrease when the power demand falls below the power supply. Since nuclear power generation and hydropower generation are difficult to adjust the output in a short time, the output adjustment by the power plant is mainly performed by the thermal power plant.

  The grid operation device 200 can instruct the power control system 100 via the communication network to release or absorb power to the power grid 50 according to the load fluctuation. Specifically, when the power demand exceeds the power supply, the power system 50 is instructed to release power, and when the power demand falls below the power supply, the power system 50 is instructed to absorb power.

  Changing the power generation output by the former thermal power plant takes several to 10 minutes. Since adjustment of power supply by the latter power control system 100 is instantaneously possible, it is particularly effective for instantaneous load fluctuations. The establishment of the frequency adjustment market described above facilitates new entry even for IPPs that have only generators that are difficult to adjust output. In other words, by utilizing the frequency adjustment service, it is possible to enter the power generation business without providing facilities relating to frequency adjustment, and it is possible to reduce the initial investment cost.

  In recent years, a mechanism for paying compensation according to frequency adjustment capability is being introduced in the frequency adjustment market. As described above, frequency adjustment using a storage battery or flywheel is superior from the frequency adjustment using a generator in terms of followability, quickness, and accuracy. In recent years, a mechanism has been introduced in which the adjustment power source having a higher adjustment capability, such as the latter, has a higher price. Under such a background, there are an increasing number of business operators (hereinafter referred to as frequency adjustment business operators) aiming to increase profits in the frequency adjustment market using storage batteries without power generation facilities. The power control system 100 is managed by a frequency adjustment operator. Note that when the power company is responsible for frequency adjustment as in Japan, the power control system 100 is managed by the power company.

  FIG. 2 is a diagram for explaining the power control system 100. The power control system 100 includes a storage battery 10, a bidirectional AC-DC converter 11, a BMU (Battery Management Unit) 12, a control device 20, a console terminal device 70, an electrical facility 80, a meter 91, and a meter 92. The storage battery 10 and the electrical equipment 80 can function as a regulated power source for frequency control, respectively or as a unit. Hereinafter, in the present specification, discharging power from the regulated power source to the power system 50 is referred to as power feeding, and absorbing power from the power system 50 by the regulated power source is referred to as power reception.

  The storage battery 10 is a battery that can be charged from the power system 50 and discharged to the power system 50. As the storage battery 10, a lithium ion battery, a nickel metal hydride battery, a lead battery, or the like is employed. The bidirectional AC-DC converter 11 is connected between the storage battery 10 and the power system 50. Bidirectional AC-DC converter 11 converts AC power supplied from power system 50 into DC power when supplied with a charge instruction from BMU 12 and supplies it to storage battery 10, and DC power supplied from storage battery 10 when there is a discharge instruction. Is converted into AC power and supplied to the power system 50.

  The BMU 12 manages the storage battery 10. Specifically, charge / discharge of the storage battery 10, remaining capacity, presence / absence of abnormality, etc. are managed. Specifically, when receiving a power reception instruction from the control device 20, the BMU 12 controls the storage battery 10 and the bidirectional AC-DC converter 11 to execute charging control from the power system 50 to the storage battery 10. On the other hand, when there is a power supply instruction from the control device 20, the storage battery 10 and the bidirectional AC-DC converter 11 are controlled to perform discharge control from the storage battery 10 to the power system 50. Further, the BMU 12 receives voltage, current, and temperature for each cell of the storage battery 10 from a CMU (Cell Management Unit) (not shown), and based on these values, performs SOC calculation, cell balance adjustment, overcharge protection, and overdischarge protection. Execute temperature abnormality detection.

  The electrical equipment 80 is an electrical equipment installed in a facility (for example, a university or a hospital) where the storage battery 10 is installed. The electric facility 80 includes at least one of a load 82 and a generator 81. The generator 81 corresponds to an emergency backup power source or a solar power generation system. The generator 81 can supply power not only to the load 82 in the facility but also to the power system 50. The load 82 is a general term for loads that consume power in the facility. The power supplied mainly from the power system 50 is consumed. For example, air conditioning equipment, lighting equipment, computer related equipment, and the like are applicable. The electrical equipment 80 may include equipment that circulates and stores energy without consuming power, such as a chiller or a storage battery that already exists in the facility. The electric equipment 80 does not necessarily have the generator 81 installed.

  When receiving a power reception instruction from the control device 20, the electric facility 80 consumes the instructed power amount from the power system 50. For example, the power consumption of the load 82 is increased by operating a stopped ventilation fan. Further, the operation of the generator 81 during power generation is stopped or the output power is reduced. In this specification, power consumption from the power system 50 includes stopping the generator 81 that is generating power or lowering the output power. Considering the net, it can be considered that the power consumption of the load 82 increases and the output power of the generator 81 decreases.

  When there is a power supply instruction from the control device 20, the electric facility 80 supplies the instructed amount of power to the power system 50. For example, the operation of the stopped generator 81 is started or the output power is increased. In the present specification, the power supply to the power system 50 includes reducing the power consumption of the load 82. Considering the net, it can be equated that the output power of the generator 81 increases and the power consumption of the load 82 decreases. Specific examples of reducing the power consumption of the load 82 include lowering of the set temperature of the air conditioner, turning off the lighting installed in a place with a low priority.

  The meter 91 is connected to a charge / discharge path between the power system 50 and the bidirectional AC-DC converter 11 and detects the amount of power exchanged between the storage battery 10 and the power system 50. The meter 91 notifies the control device 20 and / or the system operation device 200 of the detected power amount via the communication network 60. The meter 92 is connected to a lead-in line from the electric power system 50 to the electric equipment 80 and detects the amount of electric power exchanged between the electric equipment 80 and the electric power system 50. The meter 92 notifies the detected power amount to the control device 20 and / or the system operation device 200 via the communication network 60.

  A system operation device 200, a frequency adjustment market operation device 300, a control device 20, and a console terminal device 70 are connected to the communication network 60. The communication network 60 is configured by the Internet, a dedicated line, or a combination of both.

  The frequency adjustment market management apparatus 300 is constructed by various servers. The frequency adjustment market management device 300 is a device for operating the frequency adjustment market. The frequency adjustment market operation device 300 receives an offer of a frequency adjustment service from a system operator, and receives a frequency adjustment service from a frequency adjustment operator or a power generation company having a frequency adjustment facility. Accept a bid. The frequency adjustment market operating device 300 basically determines the price of the frequency adjustment service (hereinafter simply referred to as the service price) based on the supply and demand relationship between the offer and the bid.

  The power source for the service price paid by the grid operator to the winning bidder is electricity bills collected from consumers, public funds such as taxes, power generation business that does not have frequency adjustment capability or that has been outsourced to the grid operator At least one of the fees collected from the person will be charged.

  In general, the frequency adjustment market has a one-day advance market and a real-time market in the same manner as the wholesale power market. The day before PJM market is operated as follows. A bidder, such as a frequency adjustment business operator, bids in units of one hour from 0:00 to 18:00 (excluding 12 to 16:00) the day before the frequency adjustment service provision date. The minimum unit for bidding is 0.1 MW. The successful bid result is notified at 20:00 on the day before the service provision date. The service price is determined based on the market price, not the bid price. The market price is a price that matches supply and demand at the exchange, and the service price is determined not to the market price itself but to a price that has been adjusted to a certain degree. The demand is calculated from the predicted value of power demand on the day, the scheduled value of power supply on the day, and the like.

  System operators can secure a power supply for frequency adjustment in the market one day in advance. However, the electricity supply-demand balance may be disrupted more than expected due to changes in the weather of the day and the operating conditions of the power plant. In that case, we will open a real-time market and recruit additional participants in the frequency adjustment service. The real-time market will not be opened if the power supply / demand balance is within the expected range.

  The system operation apparatus 200 is constructed by various servers. The grid operation device 200 is a device for stably operating the power system 50. The grid operation apparatus 200 transmits a power supply instruction or a power reception instruction via the communication network 60 to the control apparatus 20 of the power control system 100 that provides the frequency adjustment service at that time according to fluctuations in the power supply / demand balance. . The grid operation apparatus 200 transmits a power supply instruction or a power reception instruction periodically (for example, once every 2 seconds or 4 seconds). In addition, it is not necessary to transmit an instruction | indication in the period when electric power feeding and electric power reception are not required, and you may transmit a standby instruction | indication.

  More specific description will be given below. The grid operation device 200 monitors the supply and demand balance of power, and when a gap occurs in the supply and demand balance, it calculates the amount of power for filling the gap. When power supply to the power system is necessary, a power supply instruction is transmitted to the control device 20 of the power control system 100 participating in the frequency adjustment service so as to supply the calculated amount of power. Similarly, when power reception is required, a power reception instruction is transmitted to the control device 20 of the power control system 100 participating in the frequency adjustment service so as to receive the calculated power amount. The grid operation apparatus 200 transmits the same power supply instruction or power reception instruction to the control apparatus 20 of the power control system 100 participating in the frequency adjustment service. Each control device 20 executes the frequency adjustment service by converting the amount of power specified by the power supply instruction or the power reception instruction into the amount of power supplied or received by itself according to the successful power amount.

  The console terminal device 70 is constructed by a PC or the like and is used by a frequency adjustment operator. The console terminal device 70 may be installed in the vicinity of the place where the storage battery 10 and the electrical equipment 80 are installed, or may be installed in a distant place. When one frequency adjustment operator operates and manages a plurality of power control systems 100, a common console terminal device 70 of the plurality of power control systems 100 may be installed in the operation room of the frequency adjustment operator.

  The console terminal device 70 accesses the frequency adjustment market management device 300 according to the user operation of the frequency adjustment business operator, bids on the market one day ago or the real time market, and receives the successful bid result. Further, the console terminal device 70 changes the settings of various parameters of the control device 20 according to the user operation of the frequency adjustment operator, or the storage battery 10, the bidirectional AC-DC converter 11, the BMU 12, the generator 81, the load 82, the meter. 91 and 92 are manually controlled. The control device 20 controls the storage battery 10 and the electrical equipment 80. This will be specifically described below.

(Embodiment 1)
FIG. 3 is a diagram illustrating a configuration of the control device 20 according to the first embodiment. The control device 20 includes a power supply / power reception instruction reception unit 21, an SOC acquisition unit 22, a distribution determination unit 23, a power supply / power reception control unit 24, an operation instruction reception unit 25, and a bid unit 26. These configurations can be realized by an arbitrary processor, memory, or other LSI in terms of hardware, and are realized by a program loaded in the memory in terms of software. Draw functional blocks. Accordingly, those skilled in the art will understand that these functional blocks can be realized in various forms by hardware only, software only, or a combination thereof.

  The power supply / power reception instruction receiving unit 21 receives an instruction from the system operation device 200. More specifically, a power supply instruction, a power reception instruction, or a standby instruction is periodically received from the system operation device 200 during a period of providing a frequency adjustment service (hereinafter referred to as a service provision period) that has been successful in the market one day ago or in the real time market. . For those who have made a successful bid for the frequency adjustment service, the service provision period is a period during which the grid operator is obligated to supply power according to the power supply instruction from the system operation apparatus 200 and to receive power according to the power reception instruction.

  The SOC acquisition unit 22 acquires the SOC of the storage battery 10 from the BMU 12. The distribution determining unit 23 determines a distribution rate when power is supplied to the electric power system 50 by the storage battery 10 and the electrical equipment 80 according to the set distribution rate parameter. For example, when the distribution ratio parameter is 100: 0, only the storage battery 10 supplies power and the electrical equipment 80 does not supply power. When the distribution ratio parameter is 0: 100, only the electric equipment 80 supplies power and the electric equipment 80 does not supply power. When the distribution ratio parameter is 50:50, the storage battery 10 and the electric equipment 80 supply the same amount of power. The sum of the distribution rate parameters is always 100. Similarly, the distribution determination unit 23 determines a distribution rate when the storage battery 10 and the electrical equipment 80 receive power from the power system 50 according to the set distribution rate parameter. A detailed specific example of the method for determining the distribution rate parameter will be described in a second embodiment to be described later.

  When the power supply / power reception instruction reception unit 21 receives a power supply instruction or a power reception instruction from the system operation device 200, the distribution determination unit 23 determines whether the storage battery 10 is in the power system according to the SOC of the storage battery 10 acquired by the SOC acquisition unit 22. 50 determines the amount of power to be charged from 50 or discharged to power system 50 and the amount of power consumed by electric facility 80 from power system 50 or the amount of power supplied from electric facility 80 to power system 50. A specific example of this determination process will be described later.

  The power supply / power reception control unit 24 performs charge / discharge control of the storage battery 10 and power supply / consumption control of the electric facility 80 according to the distribution determined by the distribution determination unit 23. The former is executed by instructing the BMU 12, and the latter is executed by remotely controlling the load 82 and the generator 81. When power is supplied or received by the electric facility 80, the power supply / power reception control unit 24 remotely controls the target load 82 and / or the generator 81 according to a preset program. In the program, when power supply or power reception is required, a load for lowering or increasing the power consumption, the order of the load, operation of the generator 81 or presence / absence of output adjustment, a control procedure of the generator 81, and the like are described. Yes.

  The operation instruction receiving unit 25 receives instructions from the console terminal device 70. The bid unit 26 accesses the frequency adjustment market operating device 300 according to an instruction from the console terminal device 70 or the setting program, and bids the specified amount of power to the frequency adjustment service in the specified time zone. The setting program reflects the strategy of the frequency adjustment operator. For example, there are strategies such as bidding as much as possible, bidding only for a set time period, and bidding only when the demand is greater than a predetermined value. . A strategy for bidding only for a set time period includes, for example, bidding only for a time period when the service price tends to be high from past data. A specific example of this bid strategy will be described in a third embodiment described later.

  FIGS. 4A to 4E are diagrams showing five modes in the case where power is supplied to the power system 50 using the storage battery 10 and the electric equipment 80 in response to the power supply instruction. FIG. 4A shows a form in which only the storage battery 10 supplies power to the power system 50. The distribution ratio of the supplied power is 100 for the storage battery 10 and 0 for the electrical equipment 80. FIG. 4B shows a form in which only the electric facility 80 supplies power to the power system 50. The distribution ratio of the supplied power is 0 for the storage battery 10 and 100 for the electric facility 80.

  FIG. 4C shows a form in which both the storage battery 10 and the electric facility 80 supply power to the power system 50. The distribution ratio of the supplied power is m for the storage battery 10 (0 <m <100) and (100−m) for the electric facility 80. FIG. 4D shows a form in which the storage battery 10 receives power from the power system 50 and the electrical equipment 80 supplies power to the power system 50. The distribution ratio of the supplied power is −m (0 <m) for the storage battery 10 and (100 − (− m)) for the electric facility 80. FIG. 4E shows a form in which the storage battery 10 supplies power to the power system 50 while the electrical facility 80 receives power from the power system 50. The distribution ratio of the supplied power is m (100 <m) for the storage battery 10 and (100-m) for the electric facility 80.

  The distribution determining unit 23 selects one of these five power supply modes according to a predetermined condition. In Embodiment 1, it selects according to SOC of the storage battery 10. FIG. For example, when the power supply / power reception instruction reception unit 21 receives a power supply instruction from the system operation device 200, the distribution determination unit 23 approaches the power system from at least one of the storage battery 10 and the electric facility 80 while bringing the SOC of the storage battery 10 close to an appropriate value. The power supply / power reception control unit 24 is instructed to supply power to 50. Among the power supply modes shown in FIGS. 4A to 4E, the SOC of the storage battery 10 is adjusted in the power supply modes of FIGS. 4A, 4C, 4D, and 4E.

  Generally, the appropriate range of SOC is set within a range of 10% to 90%, although it depends on the type of battery. Overcharging or over-discharging outside the appropriate SOC range will cause a reduction in battery life. In particular, in the case of a lithium ion battery, charging to a fully charged state is a major factor that shortens the battery life.

  FIG. 5 is a diagram illustrating a relationship between the SOC of the storage battery 10 and a power supply form when the storage battery 10 and the electric facility 80 are used to supply power to the power system 50. In this example, the appropriate SOC value of the storage battery 10 is set to 50%, the proper lower limit value is set to 20%, and the proper upper limit value is set to 90%. Generally, in frequency adjustment, the demand for power supply to the power system 50 is greater than the demand for receiving power from the power system 50, and the discharge rate is faster than the charge rate, so even if the appropriate value of SOC is set higher than 50%. Good. For example, it may be set to 60%.

  First, among the five power supply modes shown in FIGS. 4A to 4E, when the discharge amount from the storage battery 10 is arranged in descending order, FIGS. 4E, 4A, 4C, and 4 are arranged. (B) and FIG. In the description of FIG. 5, a model for selecting a power supply mode by paying attention to the SOC of the storage battery 10 is considered.

  In case 1, the SOC of the storage battery 10 is positioned at the appropriate upper limit value. In this case, when the power receiving instruction is received next and the storage battery 10 is charged, the SOC exceeds the appropriate upper limit value. Therefore, it is highly necessary to discharge and lower the SOC. In case 1, the distribution determining unit 23 selects any one of the power supply modes shown in FIGS. 4 (e), 4 (a), and 4 (c). In order to greatly reduce the SOC, it is preferable that the discharge amount is large. Therefore, it is preferable to select FIG. 4E from the viewpoint of only the SOC. However, in actuality, the power supply form is determined in consideration of conditions other than the SOC, such as the operating state of the electrical equipment 80, the difference in followability due to the distribution ratio between the storage battery 10 and the electrical equipment 80, and the planned instruction from the grid operation device 200. It is determined. FIG. 4E shows an exceptional power supply form. Therefore, it is also effective to select the power supply form shown in FIGS. 4 (a) and 4 (c).

  In case 2, the SOC of the storage battery 10 is located approximately in the middle between the appropriate upper limit value and the appropriate value. In this case, in order to bring the SOC of the storage battery 10 close to an appropriate value, it is necessary to discharge and lower the SOC. In case 2, the distribution determining unit 23 selects any one of the power supply modes shown in FIGS. 4 (e), 4 (a), 4 (c), and 4 (b). Note that when power supply instructions are scheduled to continue from the grid operation device 200 (for example, when a frequency adjustment service only for power supply is provided), the SOC of the storage battery 10 does not necessarily have to be rapidly reduced, as shown in FIG. It is also effective to select the power supply form b).

  In case 3, the SOC of the storage battery 10 is positioned at an appropriate value. In case 3, the distribution determining unit 23 selects any one of the power supply configurations shown in FIGS. 4B, 4C, and 4A. When the SOC of the storage battery 10 is positioned at an appropriate value, it is preferable to select FIG. 4B from the viewpoint of only the SOC. However, the frequency adjustment of the storage battery 10 is the main use, but the frequency adjustment of the electric equipment 80 is not the main use. Moreover, the storage battery 10 has higher followability to the power supply instruction. Therefore, it is not preferable to continue using only the electric equipment 80, and the storage battery 10 should also be used. FIG. 4D and FIG. 4E are exceptional power feeding modes. Therefore, when the storage battery 10 is used in the case 3, it is effective to select FIGS. 4C and 4A.

  In case 4, the SOC of the storage battery 10 is located approximately in the middle between the appropriate value and the appropriate lower limit value. In case 4, the distribution determination unit 23 selects any one of the power supply modes shown in FIGS. 4D, 4B, 4C, and 4A. In the case 4, in order to bring the SOC of the storage battery 10 close to an appropriate value, it is necessary to charge and raise the SOC. From this point of view, it is preferable to select the power supply form shown in FIG. However, FIG. 4D shows an exceptional power supply form. Therefore, it is also effective to select the power supply form shown in FIGS. 4B, 4C, and 4A.

  In case 5, the SOC of the storage battery 10 is located in the vicinity of the proper lower limit value between the proper value and the proper lower limit value. In case 5, the distribution determination unit 23 selects any one of the power supply modes shown in FIGS. 4D, 4B, and 4C. In case 5, if the power supply form of FIG. 4 (a) is selected, the SOC after discharge falls below the appropriate lower limit value, so unlike case 4, the power supply form of FIG. 4 (a) is excluded from the options. In case 5, the request to bring the SOC closer to the appropriate value is stronger than in case 4, and thus the tolerance for selecting the power supply form in FIG.

  In case 6, the SOC of the storage battery 10 is located at the appropriate lower limit value. In this case, when the power supply instruction is received next and the storage battery 10 is discharged, it falls below the appropriate lower limit value. Therefore, it is highly necessary to charge and raise the SOC. In case 6, the distribution determining unit 23 selects one of the power supply modes shown in FIGS. 4 (d) and 4 (b). 4 (a), FIG. 4 (c), and FIG. 4 (e), which are power supply modes for discharging from the storage battery 10, are excluded from the options.

  FIGS. 6A to 6E are diagrams showing five modes when power is received from the power system 50 using the storage battery 10 and the electrical equipment 80 in response to the power reception instruction. FIG. 6A shows a form in which only the storage battery 10 receives power from the power system 50. The distribution ratio of the received power is 100 for the storage battery 10 and 0 for the electrical equipment 80. FIG. 6B shows a form in which only the electric facility 80 receives power from the power system 50. The distribution ratio of the received power is 0 for the storage battery 10 and 100 for the electric facility 80.

  FIG. 6C shows a form in which both the storage battery 10 and the electric facility 80 receive power from the power system 50. The distribution ratio of the received power is m for the storage battery 10 (0 <m <100) and (100−m) for the electric facility 80. FIG. 6D illustrates a form in which the electric facility 80 receives power from the power system 50 while the storage battery 10 supplies power to the power system 50. The distribution ratio of the received power is −m (0 <m) for the storage battery 10 and (100 − (− m)) for the electric facility 80. FIG. 6E shows a form in which the storage battery 10 receives power from the power system 50 while the electric facility 80 supplies power to the power system 50. The distribution rate of the received power is m (100 <m) for the storage battery 10 and (100-m) for the electric facility 80.

  The distribution determining unit 23 selects one of these five power receiving modes according to a predetermined condition. In Embodiment 1, it selects according to SOC of the storage battery 10. FIG. For example, when the power supply / power reception instruction reception unit 21 receives a power reception instruction from the grid operation device 200, the distribution determination unit 23 brings the SOC of the storage battery 10 close to an appropriate value, while at least the storage battery 10 and the electric facility 80 from the power system 50. The power supply / power reception control unit 24 is instructed to receive power on one side. Among the power receiving modes shown in FIGS. 6A to 6E, the SOC of the storage battery 10 is adjusted in the power receiving modes shown in FIGS. 6A, 6C, 6D, and 6E.

  FIG. 7 is a diagram illustrating a relationship between the SOC of the storage battery 10 and a power receiving mode when receiving power from the power system 50 using the storage battery 10 and the electric facility 80. Also in this example, the appropriate value of SOC of the storage battery 10 is set to 50%, the appropriate lower limit value is set to 20%, and the appropriate upper limit value is set to 90%.

  First, among the five power receiving modes shown in FIGS. 6A to 6E, when the storage battery 10 is arranged in descending order of charge amount, FIG. 6E, FIG. 6A, FIG. 6C, and FIG. (B) and FIG. 6 (d). In the description of FIG. 7, a model for selecting a power supply mode by paying attention to the SOC of the storage battery 10 is considered.

  In case 1, the SOC of the storage battery 10 is located at the appropriate lower limit value. In this case, when the power supply instruction is received next and the battery 10 is discharged, the SOC falls below the appropriate lower limit value. Therefore, it is highly necessary to charge and raise the SOC. In case 1, the distribution determination unit 23 selects one of the power receiving modes shown in FIGS. 6E, 6A, and 6C. In order to increase the SOC greatly, it is preferable that the charge amount is large. Therefore, it is preferable to select FIG. 6E from the viewpoint of only the SOC. However, in practice, the power receiving mode is determined in consideration of conditions other than the SOC. FIG. 6E shows an exceptional power receiving mode. Therefore, it is also effective to select the power receiving mode shown in FIGS. 6 (a) and 6 (c).

  In case 2, the SOC of the storage battery 10 is positioned approximately in the middle between the appropriate lower limit value and the appropriate value. In this case, in order to bring the SOC of the storage battery 10 close to an appropriate value, it is necessary to charge and raise the SOC. In case 2, the distribution determining unit 23 selects one of the power receiving modes shown in FIGS. 6 (e), 6 (a), 6 (c), and 6 (b). In addition, when it is scheduled that the power reception instruction from the grid operation device 200 will continue (for example, when a frequency adjustment service only for power reception is provided), it is not always necessary to rapidly increase the SOC of the storage battery 10 (FIG. 6 ( It is also effective to select the power receiving form b).

  In case 3, the SOC of the storage battery 10 is positioned at an appropriate value. In case 3, the distribution determination unit 23 selects one of the power receiving modes shown in FIGS. 6B, 6C, and 6A. When the SOC of the storage battery 10 is positioned at an appropriate value, it is preferable to select FIG. 6B from the viewpoint of only the SOC. However, the frequency adjustment of the storage battery 10 is the main use, but the frequency adjustment of the electric equipment 80 is not the main use. Moreover, the storage battery 10 has higher followability to the power reception instruction. Therefore, it is not preferable to continue using only the electric equipment 80, and the storage battery 10 should also be used. FIG. 6D and FIG. 6E are exceptional power receiving modes. Therefore, when the storage battery 10 is used in the case 3, it is effective to select FIGS. 6C and 6A.

  In case 4, the SOC of the storage battery 10 is located approximately in the middle between the appropriate value and the appropriate upper limit value. In case 4, the distribution determining unit 23 selects any one of the power receiving modes shown in FIGS. 6D, 6B, 6C, and 6A. In the case 4, in order to bring the SOC of the storage battery 10 close to an appropriate value, it is necessary to discharge and lower the SOC. From this point of view, it is preferable to select the power receiving form shown in FIG. However, FIG. 6D shows an exceptional power supply form. Accordingly, it is also effective to select the power receiving mode shown in FIGS. 6B, 6C, and 6A.

  In case 5, the SOC of the storage battery 10 is located in the vicinity of the proper upper limit value between the proper value and the proper upper limit value. In case 5, the distribution determining unit 23 selects any one of the power supply modes shown in FIGS. 6D, 6B, and 6C. In case 5, if the power receiving form in FIG. 6A is selected, the SOC after charging exceeds the appropriate upper limit value, and unlike case 4, the power receiving form in FIG. 6A is excluded from the options. In case 5, the request to bring the SOC closer to the appropriate value is stronger than in case 4, and therefore, the tolerance for selecting the power receiving form shown in FIG.

  In case 6, the SOC of the storage battery 10 is located at the appropriate upper limit value. In this case, when the power receiving instruction is received next and the storage battery 10 is charged, it exceeds the appropriate upper limit value. Therefore, it is highly necessary to discharge and lower the SOC. In case 6, the distribution determining unit 23 selects one of the power supply modes shown in FIGS. 6 (d) and 6 (b). The power receiving modes shown in FIGS. 6A, 6C, and 6E, which are power receiving modes for charging the storage battery 10, are excluded from the options.

  In this way, the distribution determination unit 23 supplies power to the power system 50 or supplies power from the power system 50 while the SOC of the storage battery 10 approaches an appropriate value in accordance with a power supply instruction or power reception instruction from the system operation device 200. The power supply / power reception control unit 24 can be instructed to execute the control to be consumed. The control for bringing the SOC of the storage battery 10 close to an appropriate value may be executed only when the SOC is located in a specific range. For example, the control is executed only when the SOC is above the appropriate upper limit value or when the SOC is below the appropriate lower limit value, and when the SOC is located between the appropriate upper limit value and the appropriate lower limit value, the SOC of the storage battery 10 is brought closer to the appropriate value. Do not execute.

  The control for bringing the SOC of the storage battery 10 close to an appropriate value refers to control for charging / discharging the storage battery 10 to intentionally perform SOC adjustment in response to a power supply instruction or a power reception instruction. As a result of charging / discharging the storage battery 10 according to the power supply instruction or the power reception instruction, the SOC does not approach the appropriate value as a result.

  FIG. 8 is a flowchart for explaining an example of power control by the control device 20 according to the first embodiment. This flowchart shows the processing for executing the control to bring the SOC of the storage battery 10 close to the appropriate value only when the SOC is above the appropriate upper limit value and below the appropriate lower limit value.

  First, the power supply / reception control unit 24 causes the BMU 12 to initially set the storage battery 10 (S10). For example, the storage battery 10 is charged or discharged by the BMU 12 so that the SOC of the storage battery 10 becomes an appropriate value. While the frequency adjustment service is being provided (N in S12), the following processing is repeatedly executed. When the provision of the frequency adjustment service is finished (Y in S12), the following process is finished.

  The power supply / power reception instruction reception unit 21 waits for a power supply instruction or a power reception instruction from the grid operation device 200 (N in S14), and receives the instruction when the instruction is transmitted (Y in S14). In the case of a power supply instruction (Y in S16), the distribution determination unit 23 compares the SOC of the storage battery 10 acquired by the SOC acquisition unit 22 with the appropriate lower limit value (S18). When the SOC is larger than the appropriate lower limit (N in S18), the distribution determination unit 23 instructs the power supply / power reception control unit 24 to execute the discharge control of the storage battery 10 and the power supply control of the electric facility 80 according to the set distribution rate. Instruct. The power supply / power reception control unit 24 executes discharge control of the storage battery 10 and power supply control of the electric equipment 80 in accordance with the instruction (S20).

  This distribution ratio is not limited to the distribution ratio determined by paying attention to the above-described SOC, and distribution ratios determined based on various conditions can be used. When the distribution rate of the storage battery 10 is 0, the actual discharge control is not executed. Similarly, when the distribution rate of the electrical equipment 80 is 0, the actual power supply control is not executed.

  When the SOC is above the appropriate upper limit value, the distribution determination unit 23 instructs the power supply / power reception control unit 24 to execute at least the discharge control of the storage battery 10, and the power supply / power reception control unit 24 responds to the instruction. At least discharge control of the storage battery 10 may be executed. That is, the distribution determination unit 23 sets the distribution rate of the storage battery 10 to a value greater than zero.

  When the SOC is equal to or less than the appropriate lower limit value in step S18 (Y in S18), the distribution determination unit 23 supplies / receives power according to the set distribution rate so as to execute the charging control of the storage battery 10 and the power supply control of the electric facility 80. The control unit 24 is instructed. In response to the instruction, the power supply / power reception control unit 24 executes charge control of the storage battery 10 and power supply control of the electrical equipment 80 (S22). In the power supply control in step S22, the above-described power supply form shown in FIG. More specifically, the power supply / reception control unit 24 charges the storage battery 10 with a predetermined charge amount from the power system 50 and adds the charge amount to the power amount specified by the power supply instruction to the electrical facility 80. Is supplied to the power system 50.

  When the instruction received by the power supply / reception instruction reception unit 21 is a charge instruction (N in S16), the distribution determination unit 23 compares the SOC of the storage battery 10 acquired by the SOC acquisition unit 22 with the appropriate upper limit value (S24). . When the SOC is smaller than the appropriate upper limit value (N in S24), the distribution determination unit 23 instructs the power supply / power reception control unit 24 to execute the charge control of the storage battery 10 and the power consumption control of the electric facility 80 according to the set distribution rate. Instruct. In response to the instruction, the power supply / power reception control unit 24 executes charge control for the storage battery 10 and power consumption control for the electrical facility 80 (S26).

  This distribution rate is not limited to the distribution rate determined by paying attention to the above-described SOC, and a distribution rate determined based on various conditions can be used. In addition, when the distribution rate of the storage battery 10 is 0, the actual charge control is not executed. Similarly, when the distribution rate of the electrical equipment 80 is 0, the actual power consumption control is not executed.

  When the SOC is below the appropriate lower limit value, the distribution determination unit 23 instructs the power supply / power reception control unit 24 to execute at least charge control of the storage battery 10, and the power supply / power reception control unit 24 responds to the instruction. At least charge control of the storage battery 10 may be executed. That is, the distribution determination unit 23 sets the distribution rate of the storage battery 10 to a value greater than zero.

  When the SOC is equal to or greater than the appropriate upper limit value in step S24 (Y in S24), the distribution determination unit 23 supplies / receives power according to the set distribution rate so as to execute the discharge control of the storage battery 10 and the power consumption control of the electrical equipment 80. The control unit 24 is instructed. The power supply / power reception control unit 24 executes the discharge control of the storage battery 10 and the power consumption control of the electric facility 80 in accordance with the instruction (S28). In the power reception control in step S28, the above-described power reception form of FIG. More specifically, the power supply / power reception control unit 24 causes the storage battery 10 to discharge a predetermined discharge amount to the power system 50, and adds the discharge amount to the power amount specified by the power reception instruction to the electrical facility 80. Is consumed from the electric power system 50.

  As described above, according to the first embodiment, when feeding and receiving power to the power system 50 are performed using the storage battery 10 and the electrical equipment 80, for example, when performing the frequency adjustment service using the storage battery 10 and the electrical equipment 80 The battery 10 can be sufficiently exerted while protecting the storage battery 10. That is, when the frequency adjustment service is executed only by the storage battery 10, if the SOC of the storage battery 10 is out of the proper range, the power supply instruction or the power reception instruction from the grid operation device 200 is ignored or the reduction of the battery life is not accepted. Don't be. Although it can be considered to increase the capacity of the storage battery 10 to suppress the SOC from deviating from the appropriate range, the cost increases. Therefore, by utilizing the electric facility 80 as a power source for frequency adjustment service, the possibility that the SOC of the storage battery 10 falls outside the appropriate range can be reduced. In particular, when the load 82 in the electric facility 80 is subscribed to the demand response service, the control device 20 can divert the demand response system to power supply control and power consumption control by the load 82.

  Further, when power is supplied to or received from the power system 50 using the storage battery 10 and the electrical equipment 80 in accordance with a power supply instruction or a power reception instruction from the system operation device 200, power is supplied while the SOC of the storage battery 10 is close to an appropriate value. Or by receiving electric power, possibility that SOC of the storage battery 10 will remove | deviate from an appropriate range can be reduced.

  In addition, the storage battery 10 can be charged when power is supplied to the power system 50 by discharging an amount of power larger than the amount of power specified by the power supply instruction from the electric facility 80. Similarly, when the electric facility 80 absorbs an amount of power larger than the amount of power specified by the power reception instruction, the storage battery 10 can be discharged when receiving power from the power system 50. Therefore, regardless of whether a power supply instruction or a power reception instruction is received, the SOC of the storage battery 10 can be controlled in any direction, that is, in a charging direction or a discharging direction.

(Embodiment 2)
Next, a second embodiment will be described. In the first embodiment, the example in which the distribution ratio between the storage battery 10 and the electrical equipment 80 is determined mainly from the viewpoint of the SOC of the storage battery 10 has been described, but in the second embodiment, the distribution of the storage battery 10 and the electrical equipment 80 from the viewpoint of economy. An example of determining the rate will be described. In the second embodiment, the SOC limit of the storage battery 10 is ignored for easy understanding. For the same purpose, the power supply capacity and power consumption capacity limits of the electrical equipment 801 are ignored.

  As described above, the storage battery 10 has a cycle life. Therefore, the usable period becomes shorter as the charging frequency is higher, and the usable period becomes longer as the charging frequency is lower. Meanwhile, in the frequency adjustment service market, a mechanism is being introduced in which the price of the frequency adjustment service by the storage battery 10 is set higher than the price of the frequency adjustment service by the electrical equipment 80.

  This is due to the fact that the storage battery 10 is of higher quality than the electrical equipment 80 as a power source for frequency adjustment services. That is, the storage battery 10 is superior to the electric facility 80 in terms of followability, accuracy, and speed with respect to instructions from the system operation device 200. Thus, it can be said that the mechanism in which the price changes according to the quality of the frequency adjustment service is fair and reasonable.

  If quality and consideration are not linked, it is more economical and costly for the frequency adjustment service provider to bid on a low-cost, low-quality power source (for example, power consumption adjustment with an existing load, output adjustment with an existing generator). Therefore, the incentive to introduce a high-quality power source (for example, a storage battery) is reduced. It can be said that it is desirable for the system operator to introduce many high-quality power supplies and to provide the frequency adjustment service with these power supplies because the stability of the power system 50 is increased.

  Therefore, the system operator assigns a score to each frequency adjustment service providing entity (hereinafter referred to as a unit adjustment power supply) regarded as one power source as a bid unit. This score is basically set higher as the followability to the power supply instruction or the power reception instruction from the grid operation apparatus 200 is higher. The unit adjustment power source may be a physical form as long as it is a facility controlled by the same control entity. For example, the storage battery 10, the electrical equipment 80, or the combination of the storage battery 10 and the electrical equipment 80 controlled by the same control entity can be a unit regulated power source. In addition, a single generator, a single load, or a combination of a plurality of loads can be a unit adjustment power source.

  The second embodiment will be described on the assumption that the combination of the storage battery 10 and the electrical equipment 80 controlled by the same control entity is a unit adjustment power source. Further, the description will be made on the assumption that the price of the frequency adjustment service is determined based on the receiving relationship in the frequency adjustment service market and the score of each unit adjustment power source.

  FIG. 9 is a diagram illustrating a configuration of the control device 20 according to the second embodiment. In the control device 20 according to the second embodiment, a service price history holding unit 27, a charge / discharge history holding unit 28, and an optimum distribution rate calculation unit 29 are added to the configuration of the control device 20 according to the first embodiment in FIG. It is a configuration. Hereinafter, differences from the control device 20 according to the first embodiment will be described.

  The service price history holding unit 27 holds a service price history in the frequency adjustment service market. The service price history holding unit 27 holds original service prices and their statistical values. The original service price may be discarded from the oldest.

  FIG. 10 is a diagram showing the transition of monthly service prices. The graph of FIG. 10 shows the monthly average unit price of the frequency adjustment service traded in PJM from January to November 2011. The price for providing 1 MW of power per hour to the frequency adjustment service is displayed in dollars. FIG. 11 is a diagram showing the transition of the service price in time units. The graph of FIG. 11 shows the time average unit price of the frequency adjustment service traded in PJM for each of the five days from October 31 (Monday) 2011 to November 4 (Friday) 2011. Yes.

  The service prices shown in FIGS. 10 and 11 are prices before the adjustment based on the above-described score. That is, the price basically reflects only the supply-demand relationship. The service price tends to increase as the time zone in which the power of the power system 50 becomes unstable and the time zone with fewer bidders.

  The service price history holding unit 27 holds at least one of an average value, a median value, and a mode value of service prices by time zone as a statistical value. Hereinafter, an example in which an average value is used is assumed. The average value of the service price by time zone may be calculated for each group classified according to two conditions of month and weekday or holiday. For example, an average value of service prices by time zone on weekdays in November of the past 10 years, an average value of service prices by time zone on holidays in November of the past 10 years, and the like are calculated. This classification method is an example, and another classification method may be adopted. For example, the average value of the service price for each time zone may be calculated for each group classified under two conditions of month and day of the week.

  FIG. 12 is a diagram for explaining score assignment to the unit adjustment power source. The graph of FIG. 12 shows the transition (solid line) of the amount of power that should be supplied to the power system 50 or received from the power system 50 in accordance with the power supply instruction or the power reception instruction issued from the system operation device 200. A transition (dotted line) of the amount of power actually supplied to the power system 50 from the unit adjustment power supply or received from the power system 50 in accordance with the power supply instruction or power reception instruction is depicted. A higher score is given as the degree of coincidence between the solid line and the dotted line is higher. For example, a solid line and a dotted line are completely coincident with 1.0, and a score closer to 0.0 is given as the degree of divergence between the solid line and the dotted line increases.

  The unit-adjusted power supply score is certified by tests performed regularly by the grid operator. The frequency adjustment operator who uses the storage battery 10 and the electric equipment 80 obtains a higher score as the distribution ratio of the storage battery 10 is increased and the distribution ratio of the electric equipment 80 is lowered when the test is performed. Conversely, the lower the distribution rate of the storage battery 10 and the higher the distribution rate of the electrical equipment 80, the lower the score. The frequency adjustment business operator who has acquired the score needs to operate the storage battery 10 and the electric equipment 80 by matching the distribution rate at the time of the test and the distribution rate at the time of service provision as much as possible. If the unit-adjusted power supply with a score has a large difference between the followability at the time of testing and the followability at the time of service provision, the system operator may impose a penalty such as a fine on the frequency adjustment operator.

  The grid operation apparatus 200 may acquire the amount of power that the unit adjustment power supply supplies or receives via the communication network 60 in real time. In this case, the system operator can grasp in real time the degree of divergence between the followability at the time of testing and the followability at the time of service provision. Based on this divergence, the unit adjustment power supply score may be updated in a shorter span (for example, a 1-day span or a 6-hour span).

  Returning to FIG. 9, the charge / discharge history holding unit 28 holds the charge / discharge history of the storage battery 10. The charge / discharge history holding unit 28 holds the original charge / discharge history and statistical values thereof. Note that the original charge / discharge history may be discarded in the oldest order. The charge / discharge history holding unit 28 holds, for example, an average value of charge amount per day and an average value of the number of times of charge per day as statistical values. The average value of the number of times of charging per day can be calculated by dividing the average value of the charged amount per day by the capacity of the storage battery 10.

  The optimal distribution rate calculation unit 29 calculates the optimal distribution rate of the storage battery 10 and the electrical equipment 80 in which the discounted present value of the storage battery 10 is maximized. As described above, in the case of the unit adjustment power source using the storage battery 10 and the electric facility 80, a higher score can be obtained as the distribution ratio of the storage battery 10 is increased and the distribution ratio of the electric facility 80 is decreased. Therefore, the higher the distribution ratio of the storage batteries 10 is, the higher the value obtained by providing the frequency adjustment service. Further, as described above, since the storage battery 10 has a cycle life corresponding to the number of times of charging, the usable period of the storage battery 10 becomes shorter as the number of times of charging per day increases. As the distribution ratio of the storage batteries 10 is increased, the usable period of the storage batteries 10 is shortened, and the replacement frequency of the storage batteries 10 is increased. That is, the procurement cost of the storage battery 10, specifically, the depreciation cost increases.

  As described above, when the distribution ratio of the storage batteries 10 is increased, the income increases, but the cost also increases. Because of such a trade-off relationship, simply increasing the distribution rate of the storage battery 10 does not mean that it is better.

  Hereinafter, a method for calculating the optimum distribution ratio between the storage battery 10 and the electrical equipment 80 using the DCF (Discounted Cash Flow) method will be described. Specifically, a distribution rate that maximizes the discounted present value of the storage battery 10 after n (n is a natural number) years is obtained. The discounted present value is calculated by the following (Formula 1).

DPV = CF / (r + 1) + CF / (r + 1) ² +... CF / (r + 1) ⁿ + RV / (r + 1) ^n.
DPV = discounted present value of storage battery 10 after n years CF = service price r = discount rate RV = residual value of storage battery 10

  Thus, in the DCF method, the asset value (the value of the storage battery 10 in the present embodiment) is calculated by the sum of the discounted present value of the future cash flow and the discounted present value of the residual value. In the present embodiment, no particular attention is paid to the determination method of the discount rate r. For example, a rate obtained by adding a predetermined risk premium rate to a risk free rate (generally a yield of a 10-year government bond in a developed country) can be used. The risk premium rate should be higher as the service price fluctuates.

  Based on the service price history held in the service price history holding unit 27 and the reference parameter for score generation of the unit adjusted power supply (hereinafter referred to as score generation parameter), the optimum distribution ratio calculation unit 29 Years later ... Estimate service prices obtained after n years. In this embodiment, in order to simplify the model, it is assumed that service prices obtained after one year, two years,... Further, as the score generation parameter, a proportional constant “a” proportional to the followability to the power supply instruction or the power reception instruction from the system operation device 200 is used. Under this assumption, the service price CF is calculated by the following (formula 2).

CF = Sp · a (Formula 2)
Sp = Average value of total service price per year a = Score generation parameter

  The optimum distribution ratio calculation unit 29 predicts the remaining value RV of the storage battery 10 after n years based on the charge history held in the charge / discharge history holding unit 28, the capacity of the storage battery 10 and the cycle life. The remaining value RV of the storage battery 10 after n years is calculated by the following (formula 3).

RV = (TCmax−TCp) · Bc · b (Formula 3)
TCmax = cycle life (maximum number of charge)
TCp = number of times of charging until n years later Bc = capacity of storage battery 10 b = conversion constant

  In the above (Formula 3), the remaining value RV of the storage battery 10 after n years is defined as a function of the remaining number of times of charging (TCmax−TCp) and the capacity Bc of the storage battery 10. The number of times of charge TCp until n years later is calculated from the charge history held in the charge / discharge history holding unit 28. Since the remaining charge / discharge capacity retained by the storage battery 10 after n years is determined by the product of the two parameters of the remaining charge count (TCmax−TCp) and the capacity Bc of the storage battery 10, it becomes a value standard for the storage battery 10. The conversion constant b is a constant for converting the remaining charge / discharge capacity and the price, and is determined based on the market price.

  In the above (Equation 2) and (Equation 3), the score generation parameter a and the number of times of charging TCp until n years later are values that vary depending on the distribution rate m of the storage battery 10 and the distribution rate (100-m) of the electrical equipment 80. (A = f (m), TCp = f (m)). Based on the above, the optimal distribution rate calculation unit 29 calculates the distribution rate m that maximizes the discounted present value DPV of the storage battery 10 after n years of the above (Equation 1).

  FIG. 13 is a diagram for explaining a calculation example 1 of discounted present value of the storage battery 10 after five years. FIG. 14 is a diagram for explaining a calculation example 2 of the discounted present value of the storage battery 10 after five years. The vertical axis in FIGS. 13 and 14 indicates the flow of cash flow. First, cashout occurs due to the purchase of the storage battery 10. In the subsequent five years, cash-in occurs by providing a frequency adjustment service using the purchased storage battery 10 and electrical equipment 80.

  Comparing FIG. 13 and FIG. 14, the latter has a higher distribution rate m of the storage battery 10. Therefore, the score generation parameter a is higher in the latter, and the cash-in for each year increases. However, in the latter case, the number of remaining charges TCp until five years later increases, so the remaining number of charges decreases, and the remaining value RV of the storage battery 10 after five years decreases. In the examples of FIGS. 13 and 14, the discounted present value DPV of the storage battery 10 after five years is higher in the latter case. The price obtained by subtracting the purchase price of the storage battery 10 from the discounted current value DPV is the net current value NPV of the storage battery 10.

  FIG. 15 is a flowchart for explaining an operation example of the control device 20 according to the second embodiment. The optimum distribution ratio calculation unit 29 acquires the service price history from the service price history holding unit 27 and the charge frequency history from the charge / discharge history holding unit 28. Further, the score generation parameter, the capacity of the storage battery 10, and the cycle life of the storage battery 10 are acquired as external setting parameters (S40).

  The optimal distribution ratio calculation unit 29 calculates the distribution ratio m: (100−m) between the storage battery 10 and the electrical equipment 80 in which the discounted present value DPV of the storage battery 10 after n years is maximized based on the acquired data. Calculate (S42). The optimal distribution rate calculation unit 29 sets the calculated distribution rate m: (100−m) of the storage battery 10 and the electrical equipment 80 in the distribution determination unit 23.

  The distribution determination unit 23 follows the distribution ratio m: (100−m) set by the optimal distribution ratio calculation unit 29 in the test for giving a score to the unit adjustment power supply periodically performed by the system operator. The power supply / reception control unit 24 is instructed to execute the charge / discharge control of the storage battery 10 and the power supply / consumption control of the electric facility 80. The power supply / reception control unit 24 executes charge / discharge control of the storage battery 10 and power supply / consumption control of the electric facility 80 in accordance with the instruction. Thereby, the power control system 100 acquires a score corresponding to the distribution ratio m: (100−m) between the storage battery 10 and the electrical equipment 80 calculated by the optimal distribution ratio calculation unit 29 (S44).

  While the storage battery 10 and the electrical equipment 80 are providing the frequency adjustment service, the power supply / power reception control unit 24 calculates the optimum distribution ratio in response to the power supply instruction or the power reception instruction from the system operation device 200 received by the power supply / power reception instruction reception unit 21. The charge / discharge control of the storage battery 10 and the power supply / consumption control of the electrical equipment 80 are executed according to the distribution ratio m calculated by the unit 29 and specified by the distribution determination unit 23 (S46).

  As described above, according to the second embodiment, it is possible to improve the balance of the frequency adjustment provider that provides the frequency adjustment service by combining the storage battery 10 and the electric equipment 80. That is, by optimizing the distribution ratio m: (100-m) of the storage battery 10 and the electrical equipment 80 when power is supplied to or received from the power system 50 in the frequency adjustment service, the balance of the frequency adjustment business is maximized. Can be

(Embodiment 3)
In the third embodiment, attention is paid to the bid strategy for the frequency adjustment service market. In the third embodiment, a case where the distribution ratio of the storage battery 10 and the electric equipment 80 is 100: 0 will be described as an example. This is for the purpose of simplifying the explanation and clearly indicating that the bid strategy according to the third embodiment can be applied to a unit adjustment power source that uses only the storage battery 10. In addition, since the frequency adjustment provider provides the frequency adjustment service as a business, the basic strategy is to bid for the frequency adjustment service in as many time zones as possible.

  FIG. 16 is a diagram illustrating a configuration of the control device 20 according to the third embodiment. In the control device 20 according to the third embodiment, a service price history holding unit 27, a power supply / power reception history holding unit 211, and a bid time zone determination unit 212 are added to the configuration of the control device 20 according to the first embodiment in FIG. It is the structure which was made. Hereinafter, differences from the control device 20 according to the first embodiment will be described.

  The service price history holding unit 27 holds a service price history in the frequency adjustment service market. The service price history holding unit 27 holds original service prices and their statistical values. The original service price may be discarded from the oldest. This is the same as the service price history holding unit 27 included in the control device 20 according to the second embodiment.

  The power supply / power reception history holding unit 211 stores the power amount instructed by the system operation device 200 to supply power to the power control system 100 by a power supply instruction and the time transition of the power amount instructed to receive power by a power reception instruction in units of days.

  As a basic process, the bid time zone determining unit 212 refers to the service price history held in the service price history holding unit 27, determines a time zone to be bid and / or not to be bid, and the bid unit 26 Set to. More specifically, the bid time zone determination unit 212 refers to the service price history for each time zone held in the service price history holding unit 27, and the service price is predicted to be reduced in the time zone of the day. Specify at least one time zone in ascending order. The bid unit 26 skips the bid to the frequency adjustment service in the time zone set by the bid time zone determination unit 212.

  For example, the bid time zone determination unit 212 calculates the average value of the service price for each time zone from 1 o'clock to 24 o'clock, and sorts the average value in ascending order. Then, for example, four are specified in ascending order of the average value. The four time zones are set in the bid part 26. In the example of FIG. 11, the average value of the service price is small in the order of 8 o'clock, 19 o'clock, 20 o'clock, and 1 o'clock. The bid part 26 skips the bid to the frequency adjustment service in these time zones.

  FIG. 17 is a diagram illustrating a simulation example of the SOC transition of the storage battery 10. This SOC transition shows the SOC transition when the storage battery 10 is charged / discharged in accordance with all the power supply instructions and power reception instructions transmitted from the grid operation device 200 in one day. Note that the amount of power actually discharged from the storage battery 10 to the power system 50 or charged from the power system 50 to the storage battery 10 is the amount of power specified by the power supply instruction or the power reception instruction from the system operation device 200. It is normalized by the amount of power that should be awarded within the range. Moreover, the SOC transition of FIG. 17 is obtained by averaging the SOC transition of a plurality of days.

  The bid time zone determination unit 212 specifies a time zone in which the SOC of the storage battery 10 is predicted to be outside the appropriate range, and sets the time zone in the bid unit 26. The bid unit 26 skips the bid to the frequency adjustment service in the time zone set by the bid time zone determination unit 212.

  For example, the time zone when the SOC of the storage battery 10 is outside the appropriate range can be predicted from the SOC transition of FIG. In the SOC transition of FIG. 17, it can be predicted that the SOC at 24:00 falls below the appropriate lower limit value. Further, the SOC transition based only on the past history as shown in FIG. 17 may be corrected in consideration of the weather forecast information on the forecast date. For example, there is a correlation between temperature and power demand, with a positive correlation in summer and a negative correlation in winter. This is because power consumption by air conditioning increases. Moreover, since the electric power demand has a positive correlation with the economy, the SOC transition based only on the past history may be corrected by an economic index (for example, industrial production index).

  As shown in FIG. 17, in the frequency adjustment service, the amount of power supplied to the power system 50 may be greater than the amount of power received from the power system 50. In this case, if the storage battery 10 is continuously used, the remaining capacity of the storage battery 10 is lost. Therefore, it is necessary to charge the storage battery 10 in any time zone.

  The bid time zone determination unit 212 also sets a time zone during which a bid should be skipped in the power supply / power reception control unit 24. The power supply / power reception control unit 24 adjusts the SOC of the storage battery 10 in a time zone in which the bid is skipped. Usually, charge control for the storage battery 10 is executed. In addition, when SOC is more than an appropriate upper limit, the discharge control with respect to the storage battery 10 is performed.

  FIG. 18 is a flowchart for explaining a processing example for determining a time zone for skipping a bid by the control device 20 according to the third embodiment. First, the bid time zone determination unit 212 acquires a service price history (S50). Next, the bid time zone determining unit 212 refers to the history and provisionally determines a time zone in which the bid should be skipped from the viewpoint of economy (S52). Here, one time zone with the lowest service price is selected.

  Next, the bid time zone determination unit 212 predicts the SOC transition of the storage battery 10 based on the history of the power supply instruction and the power reception instruction (S54). At that time, it is taken into account that the SOC adjustment is performed in a time zone in which the bid of the SOC transition is skipped. The bid time zone determination unit 212 determines whether or not a time zone outside the appropriate range occurs as a result of the prediction of the SOC transition (S56). If it occurs (Y in S56), the bid time zone determination unit 212 increases the number of time zones in which the bid should be skipped (S58). Here, one time zone with the lowest service price in the time zone excluding the time zone that has already been skipped is selected and set to the time zone to be skipped. Thereafter, the process proceeds to operation S54.

  As a result of the prediction of the SOC transition, if a time zone outside the appropriate range does not occur (N in S56), the time zone for skipping the bid set so far is determined as the time zone for skipping the official bid. (S60).

  As described above, according to the third embodiment, the frequency adjustment that provides the frequency adjustment service using the storage battery 10 by determining the time zone to be bid based on the history of consideration of the frequency adjustment service. The balance of business can be improved. That is, by participating in a frequency adjustment service in a time zone with a high unit price and adjusting the SOC of the storage battery 10 in a time zone with a low unit price, higher profits can be obtained within an appropriate range of SOC.

  The present invention has been described based on the embodiments. Those skilled in the art will understand that these embodiments are exemplifications, and that various modifications can be made to the combinations of the respective constituent elements and processing processes, and such modifications are also within the scope of the present invention. By the way.

  In the description of the third embodiment, the case where the distribution ratio of the storage battery 10 and the electric equipment 80 is 100: 0 has been described as an example. That is, the example which provides a frequency adjustment service with the storage battery 10 single-piece | unit was given. In this regard, the distribution ratio of the storage battery 10 and the electric equipment 80 may be m (0 <m <100) :( 100−m). That is, you may provide a frequency adjustment service using both the storage battery 10 and the electrical equipment 80.

  In this case, the bid time zone determination unit 212 multiplies the simulation result of the SOC transition when the distribution ratio of the storage battery 10 is 100 by the distribution ratio m (0 <m <100) of the storage battery 10 to obtain the distribution ratio m (0 < The SOC transition when m <100) is predicted. Other processes are the same as those described in the third embodiment. In this case, since the electrical equipment 80 is used, the possibility that the SOC of the storage battery 10 falls outside the appropriate range is reduced. Therefore, the number of bids can be increased, leading to an increase in the profits of the frequency adjustment operator.

  In the description of the first to third embodiments, the storage battery 10 is used only for the frequency adjustment service, but can also be used to supply power to the load 82 used in the facility where the storage battery 10 is installed. FIG. 19 is a diagram for explaining a power control system 100 according to a modification. The power control system 100 according to the modification has a configuration in which a switch 13 is added to the power control system 100 of FIG. The switch 13 selects whether the connection destination of the bidirectional AC-DC converter 11 is the power system 50 or the lead-in line of the electric equipment 80 according to the selection signal from the control device 20. In this variation, the frequency adjustment operator can also increase profits by selling power to the facility. For example, the bid time zone determination unit 212 compares the price of the frequency adjustment service with the power sale price to the facility, and decides to bid the frequency adjustment service when the former is high and to sell power to the facility when the latter is high. .

  The service price history holding unit 27, the charge / discharge history holding unit 28, and the optimum distribution rate calculating unit 29 of the control device 20 according to Embodiment 2 of FIG. 9 may be provided in another device on the communication network 60. In this case, the distribution determination unit 23 of the control device 20 receives and uses the optimum distribution ratio of the storage battery 10 and the electrical equipment 80 calculated by the external device. Service price history holding unit 27, power supply / power reception history holding unit 211, and bid time zone determination unit 212 of control device 20 according to Embodiment 3 in FIG. 16 may also be provided in another device on communication network 60. .

  In addition, the power system 50 in this specification includes a microgrid that is a small-scale energy network. In the first to third embodiments, an auxiliary facility of a facility where the storage battery 10 is installed is assumed as the electric facility 80, but the geographical relationship between the storage battery 10 and the electric facility 80 is not questioned. If the storage battery 10 and the electrical equipment 80 are managed by the same control device 20, both can be unit adjusted power supplies. In addition, the distribution ratio between storage battery 10 and electrical facility 80 in Embodiments 2 and 3 includes the usage frequency of storage battery 10 and electrical facility 80. For example, if the distribution ratio between the storage battery 10 and the electrical equipment 80 is 75:25, the electrical equipment 80 is used once every 4 times in response to the power supply instruction or the power reception instruction.

  DESCRIPTION OF SYMBOLS 100 Power control system, 200 system operation apparatus, 500 Power supply system, 10 Storage battery, 11 Bidirectional AC-DC converter, 12 BMU, 13 Switch, 20 Control apparatus, 21 Power supply / power receiving instruction reception part, 22 SOC acquisition part, 23 Distribution determination unit, 24 power supply / reception control unit, 25 operation instruction reception unit, 26 bid unit, 27 service price history holding unit, 28 charge / discharge history holding unit, 29 optimum distribution rate calculation unit, 211 power supply / power reception history holding unit, 212 bid time zone determination unit, 30 power plant, 40 consumer, 50 power system, 80 electrical equipment, 81 generator, 82 load, 91,92 meter, 200 system operation device, 300 frequency adjustment market operation device, 60 communication network 70 Console terminal device.

Claims (5)

A storage battery capable of charging from and discharging to the power system;
A control device for controlling charging and discharging of the storage battery,
The storage battery provides an ancillary service for the electric power system for a fee, and the ancillary service is marketed on a time zone basis,
The said control apparatus determines the time slot | zone which should be bid with reference to the log | history of consideration of the ancillary service provision in the said market, The power control system characterized by the above-mentioned. A storage battery capable of charging from and discharging to the power system;
A load capable of consuming the power of the power system, an electrical facility including at least one generator capable of supplying power to the power system, and a control device for controlling the storage battery,
The storage battery and the electrical equipment provide ancillary service for the power system for a fee, and the ancillary service is marketed on a time zone basis, and the combination of the storage battery and the electrical equipment serves as a bid subject in the market. Participate in the transaction,
The said control apparatus determines the time slot | zone which should be bid with reference to the log | history of consideration of the ancillary service provision in the said market, The power control system characterized by the above-mentioned.   The control device refers to the history of the ancillary service providing consideration for each time zone, and in the order in which the price is expected to be reduced in the time zone of the day, the control device supplies the ancillary service to at least one time zone. The power control system according to claim 1, wherein the bid is skipped.   The said control apparatus skips the bid to the ancillary service of the time slot | zone when it is estimated that SOC (State Of Charge) of the said storage battery remove | deviates from an appropriate range, The one in any one of Claim 1 to 3 characterized by the above-mentioned. Power control system   The said control apparatus adjusts SOC of the said storage battery in the time slot | zone which skips a bid, The electric power control system in any one of Claim 1 to 4 characterized by the above-mentioned.

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