Electric power regulating system, and control method of electric power regulating system

Abstract

To provide an electric power regulating system capable of planning charge / discharge while considering the optimal ratio of restrictions on electricity purchase charges, charge / discharge capacity, and other uses.SOLUTION: The electric power regulating system is a system for controlling load equipment, battery equipment, and power generation equipment connected to a power grid. The system includes: a cost calculation unit 9 that calculates the cost when the battery equipment responds as a regulating force; a response possible amount calculation unit 10 that calculates the response possible amount as a balancing force after the battery equipment responds; a charging constraint consideration unit 11 that considers battery equipment operation restrictions and the time when the driving constraint occurs; and a charge / discharge planning and determination unit 12 that determines the battery equipment charge / discharge time and the response amount. The charge / discharge planning and determination unit 12 determines the charge / discharge plan based on the cost, the response possible amount, and the operational restriction.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a power regulation system and a control method for the power regulation system.

Background Art

[0002] The number of consumers introducing solar power generation systems (PV) and battery storage systems is increasing in order to improve the ratio of renewable energy and respond to disasters. In particular, electric vehicles (EVs) are being introduced because they can be used as a means of mobility, reduce electricity costs by taking advantage of the price difference depending on the time of day, generate income by providing regulation power to the grid, and supply electricity during disasters.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Patent Document 1 discloses a control method for determining the charging time and amount based on the electricity unit price and the electricity unit price of the electricity charged in the battery. By utilizing Patent Document 1, it is possible to reduce the electricity price. However, there is a problem that sufficient capacity cannot be ensured when used for other purposes such as regulation and vehicle use unless not only the reduction of expenses (purchase electricity charges) but also the electricity for emergency adjustment after executing the charge and discharge plan and the amount of electricity for other uses such as mobility use are considered.

[0005] The present invention is an invention for solving the above problems, and an object thereof is to provide a power regulation system and a control method for the power regulation system capable of planning charge and discharge by considering the constraints for purchase electricity charges, charge and discharge available amount, and other use utilization in an optimal ratio.

Means for Solving the Problems

[0006] To achieve the above object, a power adjustment system according to the present invention is a power adjustment system that controls load equipment, battery equipment, and power generation equipment connected to a power grid, and includes an expense calculation unit that calculates expenses when the battery equipment responds as an adjustment force, a response capacity calculation unit that calculates the response capacity as the adjustment force after the battery equipment responds, a charge constraint consideration unit that considers the operation constraints of the battery equipment and the time when the operation constraints occur, and a charge and discharge plan determination unit that determines the charge and discharge time and response amount of the battery equipment. The charge and discharge plan determination unit is characterized by determining a charge and discharge plan based on the expenses, the response capacity, and the operation constraints. Other aspects of the present invention will be described in the embodiments described below.

Effects of the Invention

[0007] According to the present invention, it is possible to plan charge and discharge by considering the purchase electricity price, the charge and discharge capacity, and the constraints for other uses in an optimal ratio.

Brief Description of the Drawings

[0008]

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Embodiments for Carrying Out the Invention

[0009] Hereinafter, embodiments of the present invention will be described with reference to the drawings and the like. The following description shows specific examples of the content of the present invention, and the present invention is not limited to these descriptions, and various changes and modifications can be made by those skilled in the art within the scope of the technical idea disclosed in this specification. Also, in all the drawings for explaining the present invention, those having the same function are denoted by the same reference numerals, and the repeated description thereof may be omitted.

[0010] <First Embodiment> FIG. 1 is a diagram showing the basic configuration of the power conditioning system 100 according to the first embodiment. FIG. 1 shows the system configuration of a customer including the power conditioning system 100. FIG. 1 assumes a customer's business office such as a factory or a building.

[0011] The business office is supplied with power from the power grid 1 through the switchboard 2 to the loads in the business office. Inside the business office, there are N electric vehicles (EVs) 3 used by company cars etc. and N chargers 4 capable of bidirectional charging and discharging. The business office has a load 5 (load equipment) of the business office, a smart meter 6 for measuring the amount of power consumed by the load, an EV operation management system 7 for managing the operation time of the EVs, and a power conditioning system 100 for performing overall power monitoring and control for power optimization.

[0012] The power conditioning system 100 acquires the power consumption value from the switchboard 2 and the smart meter 6, vehicle information and charging information from the charger 4, and EV operation information from the EV operation management system 7, and outputs an instruction for charging and discharging to the charger 4. This power conditioning system 100 includes an expense calculation unit 9 for calculating expenses when the electric vehicle 3 responds as the regulation power, a response capacity calculation unit 10 for calculating the response capacity as the regulation power after the electric vehicle 3 responds, a charging constraint consideration unit 11 for considering the driving constraints of the electric vehicle 3 and the time when the driving constraints occur, and a charge and discharge plan determination unit 12 for determining the charge and discharge time and response amount of the electric vehicle 3 and determining the charge and discharge plan based on the expenses, response capacity, and driving constraints.

[0013] It is assumed that this business office has a power contract in which the unit price of the power price varies for each time period. The operator can reduce the unit price charge by charging the EV with power during the time period when the power price is low and discharging power from the EV during the time period when the power price is high. On the other hand, since the main use of the EV is originally as a vehicle, it is necessary to grasp the time periods when it is staying and the time when it departs, and maintain a sufficient amount of power for vehicle use. The control for realizing the reduction of the power price based on these constraint conditions will be described using FIG. 2 of the block diagram.

[0014] FIG. 2 is a diagram showing a control block diagram for determining a charge / discharge plan according to the first embodiment. FIG. 2 shows an overview of the calculations within the power conditioning system 100. First, in addition to the expense calculation unit 9, the available response amount calculation unit 10, the charge constraint consideration unit 11, and the charge / discharge plan determination unit 12, the power conditioning system 100 has a SOC transition calculation unit 20. The SOC transition calculation unit 20 takes the SOC of each EV as input and outputs the SOC transition. Specifically, the expense calculation unit 9 takes the demand prediction value and the power price that varies for each time period as input and outputs the power purchase cost. The charge constraint consideration unit 11 takes the SOC transition as input and outputs the total available response amount. The charge constraint consideration unit 11 takes the SOC transition, the required charge amount of each EV, and the time when the required charge amount is needed as input and outputs a charge constraint index. Although the block diagram is described such that the calculations flow in one direction, as will be described later, since the power conditioning system 100 calculates the optimal solution while appropriately changing variables, the optimization planning unit performs the calculations repeatedly any number of times. The variables of this power conditioning system 100 are the charge / discharge power amounts of the EVs at each time, and the charge / discharge power amounts at each time are reflected in the final charge / discharge plan. An image of the finally output charge / discharge plan is shown in FIG. 3.

[0015] FIG. 3 is a diagram showing an example of an EV charge / discharge plan. The charge / discharge plan 30 in FIG. 3 shows the charge / discharge amounts of each EV for each time. Charging / discharging instructions will be given to the charger so that the charge / discharge amounts are as such. Note that discharging is negative and charging is positive.

[0016] The calculation content of the SOC transition calculation unit will be described. In the SOC transition calculation unit 20, based on the current SOC, the future SOC transitions of each EV are calculated. The calculation formula is calculated, for example, by Equation (1).

[0017]

Equation

[0018] Here, SOC(n, t) is the SOC of the EV in each time period. n is an arbitrary number corresponding to the number of EVs, and t indicates time. P(n, t) is a variable of the power adjustment system 100 described above and represents the amount of charge and discharge power at each time. Q max (n) is the full charge capacity of each EV. The current SOC, which is the input, is SOC(n, -1) at t = 0. It is possible to calculate the SOC that changes at each time according to the variable P(n, t) using this formula (1). This SOC(n, t) is output to the subsequent calculation unit.

[0019] The cost calculation unit 9 calculates the power purchase cost from the demand forecast value and the electricity price. The demand forecast value may be the past data of the business office, etc., or the demand forecast value calculated by other energy management may be used. If the electricity price is determined for each time period in advance by contract, it may be set in the power adjustment system in advance, or if it is linked to the retail electricity market price, this price may be used as an input. The cost calculation unit 9 calculates the power purchase cost (cost) considering the charge and discharge in each time period using the following formula (2). That is, the cost is the difference between the electricity charges during charging and discharging, and C buy (t) is calculated to calculate the cost.

[0020]

Equation

[0021] Here, C buy (t) represents the power purchase cost at each time, P demand is the demand forecast value, C electric (t) is the fluctuating electricity price. Since P(n, t) is negative for discharge, C buy (t) decreases due to discharge.

[0022] The available response amount calculation unit 10 calculates the available response amount from the SOC transition. The calculation formulas are, for example, formula (3) and formula (4). Formula (3) is the available discharge amount, and formula (4) is the available charge amount.

[0023]

Equation

[0024] Here, SOC min is the lower limit SOC of the EV, P charger is the maximum output of the charger, T is the calculation time between t and t + 1, and SOC max indicates the upper limit SOC of the EV. Equation (3) is an arithmetic expression for taking the smaller of the dischargeable capacity up to SOC min and the dischargeable capacity within the calculation time T as the dischargeable capacity. Equation (4) is an arithmetic expression for taking the smaller of the chargeable capacity up to SOC max and the chargeable capacity within the calculation time T as the chargeable capacity. P charger is considered the same for charging and discharging this time, but if the maximum outputs for discharging and charging are different, they can be considered separately. SOC min and SOC max can also be set individually for each EV.

[0025] The charge constraint consideration unit 11 calculates a charge constraint index based on the SOC transition, the required charge amount of each EV, and the required time. The arithmetic expression for the charge constraint index is given by the following equation (5). That is, the charge constraint consideration unit 11 considers the operation constraints of the EV (battery facility) and the time when such operation constraints occur. [Number]

[0026] Here, I SOC (n, t) is the charge constraint index, and SOC target (n) is the required charge rate up to a certain time T target (n). Assuming the unit of t is minutes, T target (n) will have a value of 180 if, for example, the time of use as a vehicle is 3 hours later. When this I SOC (n, t) is large, it indicates that the demand for charging at the current time is high. In this embodiment, SOC target(n)-SOC(n,t) is linearized with the difference, but the square of the difference or the like may be used. By using the square, the value becomes larger in square as the difference between SOC(n,t) and SOC target becomes larger, so that the optimization works in the charging direction as the difference from SOC target (n) becomes larger.

[0027] In the charge / discharge plan determination unit 12, optimization is performed by minimizing the term with the following formula (6) as the objective function and P(n,t) as the variable.

Equation

[0028] Here, K1 to K4 are constants for weighted optimization. By minimizing the solution of the objective function, it is possible to calculate the optimal solution according to the weighting coefficient. When K1 is made larger than other weighting coefficients, a charge / discharge plan is made such that the power purchase cost becomes smaller. When K2 is made larger than other weighting coefficients, a charge / discharge plan is made such that the dischargeable amount becomes larger. When K3 is made larger than other weighting coefficients, a charge / discharge plan is made such that the chargeable amount becomes smaller. When K4 is made larger than other weighting coefficients, a charge / discharge plan is made such that the charge constraint index becomes smaller. Thus, by implementing this objective function and weighted optimization, it is possible to plan a charge / discharge that considers the power purchase cost, the charge / dischargeable amount, and the constraints for other uses in an optimal ratio.

[0029] That is, the charge / discharge plan determination unit 12 can determine a charge / discharge plan that minimizes the objective function with the power purchase cost in the expense calculation unit 9, the dischargeable amount and the chargeable amount in the responseable amount calculation unit 10, and the charge constraint index in the charge constraint consideration unit 11 as variables.

[0030] The calculation concept of this planning unit will be described with reference to FIGS. 4 and 5. FIG. 4 is a diagram showing the calculation results of the first plan of the charge and discharge plan. FIG. 5 is a diagram showing the calculation results of the second plan of the charge and discharge plan. Assume a case where the charging timing of one EV is planned. The calculation results in the SOC transition calculation unit 20, the cost calculation unit 9, the available response amount calculation unit 10, and the charging constraint consideration unit 11 are shown in Table 40 and Table 50, the values of K1 to K4 are shown in Table 41 and Table 42, and the calculation results of each term of Equation (6) and the objective function are shown in Table 42 and Display 52.

[0031] Table 40 in FIG. 4 shows the calculation results of each value when 30 minutes is set as the interval of one calculation step. The SOC at the initial t = 0 is 80%, and the SOC target (1) is 90% at the time of t = 3. Therefore, it is necessary to plan to charge up to 90% of the SOC by this point. For example, as shown in FIG. 3, a plan to set the SOC to 90% by charging 2 kWh at the timings of t = 2 and 3 is taken as the first plan of the plan.

[0032] The SOC transition at this time is calculated by the SOC transition calculation unit 20. Since the full charge capacity Q max of the EV is set to 40 kWh, it increases by 5% with a charge of 2 kWh. Based on this SOC transition calculation result, the cost calculation unit 9 calculates C buy (t) according to Equation (2). For example, at the time of t = 2, C buy (2) = (20 + 2) × 10 = 220.

[0033] Also, the available response amount calculation unit 10 calculates the dischargeable amount and the chargeable amount based on Equations (3) and (4). For example, when P charger is 8 kW, T is 0.5, SOC min is 10%, and SOC max is 90%, at the time of t = 2, P Discharge (1, 2) = Min(40 × (85 - 10) / 100, 8 × 0.5) = 4 P charge (1, 2) = Min(40 × (90 - 85) / 100), 8 × 0.5) = 2 becomes.

[0034] In addition, in the charging constraint consideration unit 11, I target (n) is calculated by the difference between the SOC transition and SOC SOC (n,t). For example, at the time point of t = 2, I soc (1,2)=Max((90 - 85) / (3 - 2),0)=10 is obtained. When constants are determined as in K1 to K4 in Table 41, the calculation result of the objective function in Equation (6) is as shown in Table 42 in Figure 4.

[0035] Next, a comparison is made with the second plan of the charging plan implemented at t = 1 and t = 2 as shown in Figure 5. In this case, since the electricity price is lower at t = 0, 1 than in the interval of t = 2, 3, the value of the part of K1×C buy (t) is larger than that of the first plan of the plan. Also, since the SOC also rises early and approaches SOC max , the chargeable amount also becomes smaller, and the calculation result of the part of K3×1 / P charge (n,t) is also a larger value than that of the first plan of the plan. On the other hand, since SOC target (n) reaches earlier than the first plan of the plan, the part of K4×ISOC(n,t) is a smaller value than that of the first plan of the plan. As a result, the objective function becomes a smaller result than that of the first plan of the plan. Therefore, it is determined that the second plan of the plan is more suitable than the first plan of the plan and is determined as the charge and discharge plan. The charge and discharge plan is P(n,t), and based on this plan, the charger performs the charge and discharge of the EV.

[0036] Figure 6 is a diagram showing the transition of each optimization factor in time series. The image of the processing so far is shown in Figure 6. In Figure 6, the timing 60 when the electricity price rises, the timing 61 when the electricity price decreases, and the timing 62 when charging is completed are shown.

[0037] In Figure 6, it is the operation required by the cost calculation unit to perform discharge in the interval where the electricity price is high from 60 to less than 61 and to perform charging in the interval where the electricity price is low from 61 to 62. Also, it is the operation required by the response capacity calculation unit 10 to maximize the sum of the dischargeable amount and the chargeable amount corresponding to the area of the dischargeable amount and the chargeable amount in this figure. Also, SOC target64 (Required Charge), T target It is the operation required of the charging constraint consideration unit 11 to charge so as to reach the target SOC at the earliest possible time considering 63 (required time). In this embodiment, all of these are considered by weighted optimization to determine the charge-discharge plan.

[0038] FIG. 7 is a diagram showing the control flow S10 for determining the charge-discharge plan. The power adjustment system 100 calculates a charge-discharge plan that satisfies the constraint conditions at S11. At S12, it calculates the SOC transition corresponding to the block of the SOC transition calculation unit 20 in the control block diagram of FIG. 2. At S13, it executes the calculations corresponding to the blocks of the cost calculation unit 9, the available response amount calculation unit 10, and the charging constraint consideration unit 11 in the control block diagram, and calculates the purchased electricity fee, the total available response amount, and the charging constraint index (operation constraint). At S14, it executes the calculation of the objective function corresponding to the block of the charge-discharge plan determination unit in the control block diagram, and determines whether the value of the objective function is less than or equal to a predetermined value. If it is determined to be less than or equal to the predetermined value (S14, Yes), it is determined as the charge-discharge plan and output. If the conditions are not satisfied (S14, No), the plan is made again. This iterative calculation process corresponds to the process of the power adjustment system 100. The condition of S14 is that the value of the objective function is less than or equal to a predetermined value, but it may also be possible to formulate a plurality of plan proposals and adopt the one with the smallest value. That is, the charge-discharge plan determination unit 12 determines the charge-discharge plan based on the total cost, the available response amount, and the operation constraint.

[0039] K1 to K4 of this optimization change depending on whether the administrator places importance on cost, available response amount, or charging constraint. Therefore, these constants should be determined based on whether the administrator should grasp where to place importance. For example, it is desirable to determine after conducting a questionnaire at the system interface.

[0040] <Second Embodiment> In the second embodiment, an example of correcting the price considering the deterioration rate will be described. Since the battery deteriorates due to charge and discharge, if this is not considered, unnecessary charge and discharge may be performed, and it may not be possible to meet the assumed life of the vehicle. Therefore, it is necessary to operate considering deterioration. An example of considering this will be described with reference to FIG. 8.

[0041] FIG. 8 is a diagram showing a control block diagram for determining a charge and discharge plan considering deterioration according to the second embodiment. In the power adjustment system 100A of FIG. 8, a deterioration cost calculation unit 80 is added to FIG. 2, and the expense calculation unit 9 becomes a deterioration consideration expense calculation unit 81. The deterioration cost calculation unit 80 takes the deterioration rate as an input and outputs the deterioration cost. In FIG. 8, the deterioration rate is input from the charger 4, but the means such as the method of acquiring it by communication from the charger 4 or the method of estimating it from the charge and discharge behavior of the charger 4 are not limited.

[0042] FIG. 9 is a diagram showing an image of judgment when considering deterioration. In the deterioration cost calculation unit 80, it is judged whether the deterioration rate is above the assumption as shown in FIG. 9. FIG. 9 shows the number of years of use (Time) on the horizontal axis and the deterioration rate of the capacity (State of Health of Q: SOHQ) on the vertical axis. The vertical dotted line indicates the number of years of the vehicle life, for example, the number of years of vehicle warranty. The battery life is set to a value that is dangerous in terms of safety when it is less than that. The curve in the figure is an assumed deterioration curve, which is a deterioration curve calculated by a separately calculated deterioration formula and in which the number of years of vehicle life and the battery life match. For example, if the acquired deterioration rate is above the assumed deterioration curve like pattern A, it means that it has deteriorated less than the assumption, so there is room for use other than vehicle use. On the other hand, if it is below the assumed deterioration curve like pattern B, it means that it has deteriorated more than the assumption, so if it is used other than vehicle use, it may not be possible to meet the assumed life of the vehicle, and it is not appropriate to use it other than vehicle use. In such a case, for example, the deterioration cost is considered separately according to the flowchart shown in FIG. 10.

[0043] FIG. 10 is a diagram showing an operation flow S20 of deterioration cost. The deterioration cost calculation unit 80 acquires a deterioration rate in S21. In S22, it is determined whether the deterioration rate is equal to or higher than the assumed deterioration curve. If the deterioration rate is equal to or higher than the assumed deterioration curve (S22, Yes), the process proceeds to S23 and the deterioration cost is defined by Expression (7).

[0044] [Number]

[0045] Here, C deg (n) is referred to as the deterioration cost and is the cost incurred for each kWh of discharge. A is a constant and has a value between 0 and 1. C product is the cost per kWh of the product. For example, if it is 4 million yen and the lifetime dischargeable capacity is 120,000 kWh, it is 33.3 yen / kWh. Regarding this lifetime discharge capacity, catalog values may be referred to, or it may be calculated separately by deterioration estimation. Thus, it means that a value of 33.3 yen is lost for each kWh of discharge. When the deterioration rate is equal to or higher than the assumed curve, since there is a margin compared to the assumed life of the vehicle, it is treated as having less loss than this C product . Therefore, it is multiplied by A. That is, the deterioration consideration expense calculation unit 81 (expense calculation unit 9) determines that the loss price of the equipment lost due to charge and discharge is small when it has not deteriorated more than the deterioration rate assumed based on the operating years, and corrects the loss price.

[0046] On the other hand, if the deterioration rate is less than the assumed deterioration curve (S22, No), the process proceeds to S24 and the deterioration cost is defined by Expression (8). [Number]

[0047] Next, the deterioration consideration expense calculation unit 81 calculates the total cost (expense) considering the deterioration cost by the following Expression (9). That is, the deterioration consideration expense calculation unit 81 (expense calculation unit) calculates the expense including the loss price of the equipment lost due to discharge. [Number]

[0048] Here, the reason for processing to select the smaller value when comparing with 0 in the part of Min(0, P(n, t)) is to extract only the discharge part. By using this formula, the cost considering the deterioration cost of the discharged capacity can be output to the subsequent stage. Therefore, optimization is executed so that discharge does not occur when the profit is not large enough even though the deterioration is larger than expected. As a result, cases where the assumed life of the vehicle cannot be satisfied can be suppressed. The subsequent calculations are the same as those in the first embodiment such as Equation (6), so they are omitted.

[0049] <Third Embodiment> The third embodiment will explain the calculation of expenses when the target business office has an electricity contract with a basic charge according to the maximum demand. Reducing this basic charge is called peak cut with the aim of reducing the maximum demand. In the case of this business office, achieving peak cut will result in cost reduction.

[0050] FIG. 11 is a diagram showing a control block diagram of charge / discharge plan determination considering peak cut according to the third embodiment. FIG. 12 is a diagram showing an image of calculating the peak cut excess amount. The power adjustment system 100B in FIG. 11 has the expense calculation unit 9 as the peak cut consideration unit 110 compared with FIG. 2. In the peak cut consideration unit 110, the peak cut excess amount is calculated from the demand prediction value and the peak cut target value and reflected in the objective function. The calculation formula is, for example, Equation (10).

[0051]

Equation

[0052] The reference numeral 120 in FIG. 12 within the Max term is the transition of the total demand value within the business office including the charge / discharge output of the EV. P threshold is the peak cut target value 121. P excessshows the peak cut excess amount 122 from the peak cut target value 121. This relationship will be described with reference to FIG. 12. FIG. 12 shows the predicted time-series change of power demand, where the reference numeral 120 represents the transition of the total demand value within the business premises including the charge and discharge output. This is the P of the peak cut target value 121 threshold can be reduced by setting it as follows. Therefore, it is necessary to reduce the P of the peak cut excess amount 122 excess of this. To reduce this P excess the objective function is changed to the following formula (11).

[0053] [Number]

[0054] Here, K5 is a constant for weighted optimization. By minimizing the objective function formula (11), a charge and discharge plan is formulated in a direction to reduce the peak cut excess amount, and control considering the expenses due to peak cut becomes possible.

[0055] That is, when implementing peak cut control aimed at reducing the contract power, the charge and discharge plan determination unit 12 determines the charge and discharge plan based on the amount of power predicted to exceed the contract power value.

[0056] [Fourth Embodiment] FIG. 13 is a diagram showing the basic configuration of a power adjustment system utilizing a stationary battery according to the fourth embodiment. In the fourth embodiment, the same processing as in the embodiment described for the battery facility instead of the EV will be described for the content that can be implemented.

[0057] FIG. 13 has the same configuration as FIG. 1, but the electric vehicle 3 and the charger 4 are changed to a stationary battery 130 and a converter 131. Also, the EV operation management system 7 is changed to a battery management system 132. The stationary battery 130 is, for example, one introduced for the purpose of supplying power to a business office during a power outage. It is assumed that this stationary battery 130 can also be used for other purposes even if it is not for vehicle use. For example, since power consumption is high during the day, there is a constraint that it is kept fully charged in preparation for a power outage. Based on this, it is possible to execute the calculation process in the same manner as in the first embodiment. Since the calculation process is the same as in the first embodiment, it will be omitted. Thus, even for the stationary battery 130 that does not have a clear other use such as an EV, it is possible to secure the capacity for use in other purposes with the same concept.

[0058] <Fifth Embodiment> In the first embodiment, the constant for weighted optimization was to be determined by the system administrator, but the change of this constant due to external factors will be explained.

[0059] FIG. 14 is a diagram showing a control block diagram of charge / discharge plan determination for changing optimization conditions according to external factors according to the fifth embodiment. The power adjustment system 100C in FIG. 14 takes weather information, traffic information, and power information as inputs as external factors. These pieces of information are input from a weather information input unit 140, a traffic information input unit 141, and a power information input unit 142, and are used in calculations by an optimization condition determination unit 143. The optimization condition determination unit 143 determines an optimization constant based on these pieces of information and outputs it to the charge / discharge plan determination unit 12.

[0060] FIG. 15 is a diagram showing the change of the constant according to the weather information. When bad weather occurs and the probability of a power outage or the like increases, a larger amount of dischargeable power should be secured from the EV. Also, during bad weather, it is conceivable to use the EV and move earlier than expected. Therefore, for example, the precipitation probability is input as an indicator of bad weather, and K2 and K4 are increased as shown in FIG. 15. By doing so, when the probability of bad weather is high, it is possible to secure the dischargeable amount and the SOC target can be secured at an early stage.

[0061] That is, the power adjustment system further includes an optimization condition determination unit 143 that determines the weighting of cost, response capacity, and operation constraints based on external factors. When determining the charge and discharge plan based on cost, response capacity, and operation constraints, the optimization condition determination unit 143 takes weather information as an input, and when it is determined that the weather is bad, increases the weight of the determination of response capacity and operation constraints compared to cost.

[0062] FIG. 16 is a diagram showing changes in constants based on traffic information. When the transportation system is disrupted, it is considered that the probability of using the EV at a time earlier than T increases. Therefore, as an indicator of the disruption of the transportation system, the surrounding traffic congestion loss time and the number of delay information of public transportation are input, and K4 is increased as shown in FIG. 16. By doing so, when the transportation system is disrupted, SOC can be ensured early and the vehicle can be used for vehicle applications early. target It is considered that it is more likely to be used earlier than T. Therefore, as an indicator of the disruption of the transportation system, the surrounding traffic congestion loss time and the number of delay information of public transportation are input, and K4 is increased as shown in FIG. 16. By doing so, when the transportation system is disrupted, SOC can be ensured early and the vehicle can be used for vehicle applications early. target can be secured and early use for vehicle applications becomes possible.

[0063] That is, the power adjustment system further includes an optimization condition determination unit 143 that determines the weighting of cost, response capacity, and operation constraints based on external factors. When determining the charge and discharge plan based on cost, response capacity, and operation constraints, the optimization condition determination unit 143 takes traffic information as an input, and when it is determined that traffic congestion occurs, increases the weight of the determination of operation constraints compared to cost and response capacity.

[0064] FIG. 17 is a diagram showing changes in constants based on power information. When the probability of a power outage is high, a large amount of dischargeable power should be secured from the EV. Also, during a power outage, it is considered that the EV should be used and moved earlier than expected. Therefore, for example, the power shortage rate is input as an indicator of the probability of a power outage, and K2 and K4 are increased as shown in FIG. 17. By doing so, when the probability of a power outage is high, it becomes possible to secure the dischargeable amount and SOC early. The subsequent processing in the charge and discharge plan determination unit 12 is the same as that in the first embodiment, so it is omitted. target can be secured. The subsequent processing in the charge and discharge plan determination unit 12 is the same as that in the first embodiment, so it is omitted.

[0065] That is, the power adjustment system further includes an optimization condition determination unit 143 that determines the weighting of costs, the amount of response, and operation constraints based on external factors. When determining the charge and discharge plan based on costs, the amount of response, and operation constraints, the optimization condition determination unit 143 takes power information as input, and when it is determined that power is in short supply and a power outage will occur, it increases the weight of the determination of the amount of response and operation constraints compared to costs.

[0066] <Sixth Embodiment> FIG. 18 is a diagram showing the basic configuration of a power adjustment system 100D having a solar power generation system according to the sixth embodiment. In this embodiment, a power adjustment system that takes into account the self-consumption rate will be described. A power generation facility 180 (solar power generation panel 181, converter 182) is added to the system shown in FIG. 1 of the first embodiment. In order for the business office to improve the self-consumption rate, a solar power generation panel (PV) is introduced. Also, it is assumed that the business office cannot feed power back to the grid through the switchboard. Therefore, when the power generation amount of the PV is large and the load is small, the power generation of the PV must be suppressed and the power generation of the PV cannot be effectively utilized. As a countermeasure, a self-consumption rate consideration unit 190 is added to the optimization calculation as shown in FIG. 19.

[0067] FIG. 19 is a diagram showing a control block diagram of charge and discharge plan determination considering the self-consumption rate according to the sixth embodiment. The power adjustment system 100D in FIG. 19 has a self-consumption rate consideration unit 190 added as a change from the block diagram in FIG. 2 of the first embodiment. The self-consumption rate consideration unit 190 calculates the power generation suppression amount based on the predicted PV power generation amount and the predicted demand value, and outputs it to the subsequent charge and discharge plan determination unit. The power generation suppression amount is calculated by the following formula (12).

[0068]

Equation

[0069] Here, P in formula (12) suppression (t) is the suppression amount of the PV, and P PV represents the predicted PV power generation amount. This P suppression(t) and demand will be described with reference to FIG. 20.

[0070] FIG. 20 is a diagram showing an image of output suppression of a photovoltaic power generation system. The solid black line in the figure indicates the total demand value in the business office including the charge and discharge output, and the dotted black line in the figure indicates the predicted PV power generation amount 200. The PV suppression amount 201 of the double arrow in the figure suppression Since the power generation amount is larger than the demand, the PV power generation in this part is suppressed. Minimizing this amount makes it possible to effectively utilize PV power generation. Therefore, the PV suppression amount is added to the objective function as in Equation (13).

[0071]

Equation

[0072] Here, K6 is a constant for weighted optimization. By minimizing the objective function formula (13), the charge and discharge plan is formulated in the direction of reducing the PV suppression amount.

[0073] That is, the charge and discharge plan determination unit 12 determines the charge and discharge plan based on the suppression amount predicted to suppress the operation of the power generation facility 180.

[0074] As described above, the power adjustment system of the present embodiment has been described. The power adjustment method has the following features. A control method for a power adjustment system that controls a load facility, a storage battery facility, and a power generation facility connected to a power grid, the method including: an expense calculation step for calculating an expense when the storage battery facility responds as an adjustment force; a response capacity calculation step for calculating the response capacity as the adjustment force after the storage battery facility responds; a charge constraint consideration step for considering the operation constraints of the storage battery facility and the time when the operation constraints occur; and a charge and discharge plan determination step for determining the charge and discharge time and response amount of the storage battery facility. The charge and discharge plan determination step is characterized by determining the charge and discharge plan based on the expense, the response capacity, and the operation constraints.

Description of Signs

[0075] 1 Power grid 2 Distribution board 3 Electric vehicle (battery equipment) 4 Charger 5 Load (load equipment) 6 Smart meter 7 EV operation management system 9 Expense calculation section 10 Responsive energy calculation section 11 Charging constraint consideration section 12 Charge-discharge plan determination section 20 SOC transition calculation section 30 Charge-discharge plan 60 Timing when electricity price rises 61 Timing when electricity price decreases 62 Timing when charging is completed 63 T target (Required time) 64 SOC target (Required charge amount) 80 Degradation cost calculation section 81 Degradation consideration expense calculation section 100 Power adjustment system 110 Peak cut consideration section 120 Transition of total demand value within the business premises including EV charge-discharge output 121 Peak cut target value 122 Peak cut excess amount 130 Stationary battery (battery equipment) 131 Converter 132 Battery management system 140 Weather information input section 141 Traffic information input section 142 Power information input section 143 Optimization condition determination section 180 Power generation equipment 181 Solar power generation panel 182 Converter 190 Self-consumption rate consideration section 200 PV power generation prediction value 201 PV suppression amount

Claims

1. A power regulation system for controlling load equipment, battery equipment, and power generation equipment connected to a power system, comprising: a cost calculation unit that calculates costs when the battery equipment responds as a regulation force; a response capacity calculation unit that calculates the response capacity as the regulation force after the battery equipment responds; a charge constraint consideration unit that considers the operation constraints of the battery equipment and the time when the operation constraints occur; a charge and discharge plan determination unit that determines the charge and discharge time and response amount of the battery equipment; The charge and discharge plan determination unit determines a charge and discharge plan based on the cost, the response capacity, and the operation constraints. A power regulation system characterized by this.

2. The power regulation system according to claim 1, wherein the cost is the difference in electricity rates between charging and discharging. A power regulation system characterized by this.

3. The power regulation system according to claim 2, wherein the cost calculation unit calculates the cost including the loss price of equipment that will be lost due to discharge. A power regulation system characterized by this.

4. The power regulation system according to claim 3, wherein when the loss price of equipment that will be lost due to charge and discharge is not deteriorated more than the deterioration rate assumed based on the number of operating years, the cost calculation unit determines that the loss price is small and corrects the loss price. A power regulation system characterized by this.

5. The power regulation system according to claim 1, wherein when implementing peak cut control for the purpose of reducing the contract power, the charge and discharge plan determination unit determines a charge and discharge plan based on the amount of power predicted to exceed the contract power value. A power regulation system characterized by this.

6. The power regulation system according to claim 1, wherein the power regulation system further includes an optimization condition determination unit that determines the weighting of the cost, the response capacity, and the operation constraints based on external factors, and when determining a charge and discharge plan based on the cost, the response capacity, and the operation constraints, the optimization condition determination unit inputs weather information, and when it is determined that the weather is bad weather, the optimization condition determination unit increases the weight of the determination of the response capacity and the operation constraints compared to the cost. A power regulation system characterized by this.

7. The power regulation system according to claim 1, wherein the power regulation system further includes an optimization condition determination unit that determines the weighting of the cost, the response capacity, and the operation constraints based on external factors, When determining the charge-discharge plan based on the cost, the available response amount, and the operation constraints, the optimization condition determination unit takes traffic information as an input. When it is determined that traffic congestion has occurred, the optimization condition determination unit increases the weight of the determination of the operation constraints compared to the cost and the available response amount. A power adjustment system characterized by the above.

8. The power adjustment system according to claim 1, wherein the power adjustment system further includes an optimization condition determination unit that determines the weighting of the cost, the available response amount, and the operation constraints based on external factors. When determining the charge-discharge plan based on the cost, the available response amount, and the operation constraints, the optimization condition determination unit takes power information as an input. When it is determined that power is in short supply and a power outage has occurred, the optimization condition determination unit increases the weight of the determination of the available response amount and the operation constraints compared to the cost. A power adjustment system characterized by the above.

9. The power adjustment system according to claim 1, wherein the charge-discharge plan determination unit determines the charge-discharge plan based on the predicted suppression amount by which the operation of the power generation facility is suppressed. A power adjustment system characterized by the above.

10. The power adjustment system according to claim 1, wherein the charge-discharge plan determination unit determines the charge-discharge plan that minimizes the objective function with the power purchase cost in the cost calculation unit, the dischargeable amount and the chargeable amount in the available response amount calculation unit, and the charge constraint index in the charge constraint consideration unit as variables. A power adjustment system characterized by the above.

11. A control method for a power adjustment system that controls a load facility, a battery facility, and a power generation facility connected to a power grid, including a cost calculation step of calculating the cost when the battery facility responds as the adjustment power, an available response amount calculation step of calculating the available response amount as the adjustment power after the battery facility has responded, a charge constraint consideration step of considering the operation constraints of the battery facility and the time when the operation constraints occur, and a charge-discharge plan determination step of determining the charge-discharge time and the response amount of the battery facility, wherein the charge-discharge plan determination step determines the charge-discharge plan based on the cost, the available response amount, and the operation constraints. A control method for a power adjustment system characterized by the above.

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