Demand control device, hydrogen production system, and demand control method

Abstract

To reduce an excess amount from contract power in a hydrogen production plant in which renewable energy power is used.SOLUTION: According to an embodiment, a demand control device 100 includes: an input unit that receives input information including conditions concerning transfer power including a hydrogen production planned value, an actual value of a power load of a hydrogen production apparatus, an actual value of transfer power, and maximum received electric energy; a storage unit that stores them; a first control target command value calculation unit 141 that outputs a first control command calculation value using predetermined electric energy and the actual value of transfer power; a second control target command value calculation unit 142 that outputs a second control command calculation value using the hydrogen production planned value and an actual value of a hydrogen production quantity; a safety factor calculation unit 145 that calculates a safety factor that defines the degree of compliance of a condition of the maximum received electric energy; and a command value calculation unit 146 that, based on the first control command calculation value, the second control command calculation value, and the safety factor, calculates a power load command value of the hydrogen production apparatus.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] FIELD An embodiment of the present invention relates to a demand control device and a demand control method. [Background technology]

[0002] In hydrogen production plants that use renewable energy (hereafter referred to as "renewable energy"), electricity charges account for a large proportion of operating costs. Regarding electricity charges, a metered charge is paid for the amount of electricity received from the power grid, while a basic charge is paid based on, for example, the maximum 30-minute amount of electricity used in a year (hereafter referred to as "contracted power"). For example, if hydrogen production volume is low due to hydrogen demand or if renewable energy generation is very high, it is possible that almost no electricity is received from the power grid for a month. Even in this case, a basic charge equivalent to the contracted power must be paid. For this reason, in order to reduce the operating costs of a hydrogen production plant, it is desirable to keep the contracted power as low as possible. However, if the 30-minute amount of electricity exceeds the contracted power even once, a penalty may be paid for that amount, and the contracted power may also increase from the following month. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-96709 [Patent Document 2] Patent No. 7134043 Summary of the Invention [Problem to be solved by the invention]

[0004] Hydrogen production plants that use renewable energy must produce enough hydrogen to meet demand while making effective use of renewable energy-generated power. While there is a target for the amount of hydrogen to be produced in a given period (for example, one day), if the amount of renewable energy-generated power suddenly decreases, it is possible that the 30-minute amount of power will exceed the contracted power. Therefore, while assuming that hydrogen will be produced by making effective use of renewable energy-generated power, it is necessary to control the amount of hydrogen produced so that the 30-minute amount of power does not exceed the contracted power as much as possible, taking into account fluctuations in renewable energy-generated power.

[0005] An object of the present invention is to provide a demand control device and a demand control method that can suppress the amount of excess power over the contracted power for a hydrogen production plant that uses power generated from renewable energy. [Means for solving the problem]

[0006] In order to achieve the above-mentioned object, a demand control device according to an embodiment of the present invention is a demand control device that controls the power load of a hydrogen production device in a hydrogen production plant that is connected to an external power grid and that is provided with a renewable energy power generation device, a hydrogen production device to which a hydrogen production plan value is given, and a power meter for trade that measures the power exchanged with the power grid, and that includes an input unit that receives input information including the hydrogen production plan value, an actual value of the power load of the hydrogen production device, an actual value of the power exchanged by the power meter, and conditions related to the power exchanged, including a maximum amount of power to be received, and a memory unit that stores the input information received by the input unit. a first control target command value calculation unit that calculates a first control command calculation value by control calculation using a predetermined amount of power as a target value and an actual value of the power exchanged as a feedback signal; a second control target command value calculation unit that calculates a second control command calculation value by control calculation using the planned hydrogen production value as a target value and an actual value of the amount of hydrogen produced by the hydrogen production device as a feedback signal; a safety factor calculation unit that calculates a safety factor that specifies the degree of compliance with the condition of the maximum amount of power received; and a command value calculation unit that calculates a power load command value for the hydrogen production device based on the first control command calculation value, the second control command calculation value, and the safety factor. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a block diagram showing the configuration of a hydrogen production system according to a first embodiment. [Figure 2] 1 is a block diagram showing a configuration of a demand control device according to a first embodiment. [Figure 3] FIG. 2 is a control block diagram showing the operation of the demand control device according to the first embodiment. [Figure 4] FIG. 2 is a block diagram showing a configuration of a demand control device according to a modified example of the first embodiment. [Figure 5] FIG. 2 is a flowchart showing the procedure of a demand control method according to the first embodiment. [Figure 6] FIG. 10 is a block diagram showing the configuration of a demand control device according to a second embodiment. [Figure 7] FIG. 10 is a block diagram showing the configuration of a hydrogen production system according to a third embodiment. [Figure 8] FIG. 10 is a block diagram showing the configuration of a demand control device according to a third embodiment. [Figure 9] FIG. 10 is a block diagram showing the configuration of a hydrogen production system according to a fourth embodiment. [Figure 10] FIG. 10 is a block diagram showing the configuration of a demand control device according to a fourth embodiment. [Figure 11] FIG. 10 is a block diagram showing the configuration of a hydrogen production system according to a fifth embodiment. [Figure 12] FIG. 10 is a block diagram showing a configuration of a demand control device according to a fifth embodiment. [Figure 13] FIG. 10 is a block diagram showing the configuration of a demand control device according to a sixth embodiment. [Figure 14] FIG. 13 is a flowchart showing the procedure of a demand control method according to a sixth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, a demand control device, a hydrogen production system, and a demand control method according to embodiments of the present invention will be described with reference to the drawings. Hereinafter, identical or similar parts will be denoted by common reference numerals, and duplicated explanations will be omitted.

[0009] [First embodiment] FIG. 1 is a block diagram showing the configuration of a hydrogen production system 40 according to the first embodiment.

[0010] The hydrogen production system 40 includes a hydrogen production plant 10 , a hydrogen production planning device 41 and a demand control device 100 .

[0011] The hydrogen production plant 10 includes a renewable energy power generation device 11 , a hydrogen production device 21 , and an in-house bus 31 .

[0012] The renewable energy power generation device 11 is, for example, a power generation device that uses solar power generation, wind power generation, or the like. Electric power generated by the renewable energy power generation device 11 is supplied to an in-station bus 31. In this embodiment, an example is shown in which the renewable energy power generation device 11 generates electricity in accordance with environmental conditions such as solar power or wind power, and supplies the electricity to the in-station bus 31 without output being restricted by a power conditioner (not shown) or the like.

[0013] The hydrogen production device 21 receives power as a power load from the in-house bus 31 and produces hydrogen by water electrolysis. The hydrogen production device 21 produces hydrogen based on a power load command value from the demand control device 100. That is, the hydrogen production device 21 has its own control device, and converts the power load command value received by the control device into a hydrogen production amount command value, and the hydrogen production device 21 produces hydrogen based on the hydrogen production amount command value. The hydrogen production device 21 also outputs an actual hydrogen production value.

[0014] The on-site bus 31 is connected to an external power system 1, and is capable of supplying and receiving power to and from the external power system 1. A power meter 1a is provided for measuring the power supplied and received from the power system 1. In FIG. 1, circuit breakers, transformers, and the like provided between the power system 1 and the on-site bus 31 are not shown.

[0015] The hydrogen production planning device 41 plans the hydrogen production schedule of the hydrogen production plant 10 and outputs the hydrogen production plan value.

[0016] The demand control device 100 receives as input information the hydrogen production planning value from the hydrogen production planning device 41, the measured value of the power exchanged by the power market meter 1a, and the actual hydrogen production value from the hydrogen production device 21, and controls the amount of power received by the hydrogen production plant 10 from the power grid 1 that exceeds the contracted power. In addition, although not shown, the demand control device 100 receives as input information the actual output value of the renewable energy power generation device 11, as necessary.

[0017] FIG. 2 is a block diagram showing the configuration of the demand control device 100 according to the first embodiment.

[0018] Before explaining the configuration of the demand control device 100, we will define the indices used in relation to time. First, as an index related to the exchange of power with the power grid 1, for example, the time width of a divided unit time obtained by dividing a day, that is, from 0:00 to 24:00, into multiple parts will be called the divided unit time width T. For example, if a day is divided into 48 parts, the divided unit time width T of 30 minutes will be called one frame. Furthermore, the total number of divided unit times in a day will be represented as M (M = 1 day / T), and the order of a certain divided unit time in a day will be represented as m (m = 1 to M).

[0019] As an index related to the calculation, the interval between each calculation time t (interval between calculation steps) within the division unit time width T is called the calculation step width and is represented by Δt. The calculation step width Δt is, for example, one minute. In this case, if the division unit time width T is 30 minutes, 30 steps of calculation will be performed within the division unit time width T. The total number of calculation steps within the division unit time T is represented as N (N=T / Δt), the order of a calculation step within the division unit time T is represented as n (n=1 to N), and the time is represented as time t. For example, if the division unit time width T is 30 minutes and the calculation step width Δt is one minute, N is 30 and n is 1 to 30. The period during which the demand control device 100 continuously executes control will be referred to as the control period. The control period is, for example, one year.

[0020] The demand control device 100 includes an input unit 110 , a storage unit 120 , a calculation unit 140 , and an output unit 160 .

[0021] The input unit 110 accepts as input information the planned hydrogen production value from the hydrogen production planning device 41, the measured value of the power received and sent from the power market meter 1a, and the actual hydrogen production value from the hydrogen production device 21. The input unit 110 also accepts as input information the time periods during which the maximum amount of received power must be observed as a condition for receiving and sending power, the maximum amount of received power Gmax that must be observed in each time period, the capacity of the renewable energy power generation device 11, and control parameters such as PID constants and control periods for control calculations in the calculation unit 140. The input unit 110 may accept other information as input information in addition to the above information. The maximum amount of received power is given, for example, as the total value (integral value) of the received power over the division unit time width T.

[0022] The storage unit 120 includes a performance value storage unit 121 , a maximum received power amount storage unit 122 , a control parameter storage unit 124 , a hydrogen production plan storage unit 125 , and a calculation result storage unit 126 .

[0023] The actual value storage unit 121 stores and stores information relating to actual values ​​such as the measured value of the power transferred by the power meter 1a received by the input unit 110 and the actual value of hydrogen production from the hydrogen production device 21.

[0024] The maximum receiving power amount storage unit 122 stores and memorizes the maximum receiving power amount and the time period to be observed as conditions related to power transmission and reception received by the input unit 110. Hereinafter, the maximum receiving power amount over the division unit time width will be referred to as the maximum receiving power amount Gmax.

[0025] The control parameter storage unit 124 stores and stores the control parameters for the control calculations received by the input unit 110 .

[0026] The hydrogen production plan storage unit 125 stores and stores the hydrogen production plan values ​​from the hydrogen production planning device 41 received by the input unit 110.

[0027] The calculation result storage unit 126 stores and stores the results of calculations performed by each element of the calculation unit 140.

[0028] The calculation unit 140 has a first control target command value calculation unit 141 , a second control target command value control calculation unit 142 , a safety factor calculation unit 145 , a command value calculation unit 146 , an extension remaining time calculation unit 147 , and a determination unit 155 .

[0029] The first control target command value calculation unit 141 performs control calculation using a predetermined amount of power as a target value and the actual value of the power transfer as a feedback signal to calculate a first control command calculation value. Details of the first control target command value calculation unit 141 will be described later with reference to FIG. 3.

[0030] The second control target command value control calculation unit 142 performs control calculation using the planned hydrogen production value as a target value and the actual value of the amount of hydrogen produced by the hydrogen production plant 10 as a feedback signal to calculate a second control command calculation value. Details of the second control target command value calculation unit 141 will be described later with reference to FIG. 3.

[0031] The safety factor calculation unit 145 calculates a safety factor Safe that specifies the degree of compliance with the condition for the maximum amount of received power. The safety factor Safe has a value between 0 and 1. The closer the safety factor Safe is to 1, the greater the degree of compliance with the condition for the maximum amount of received power Gmax. When the safety factor Safe is 1, hydrogen production is suppressed so that the received power completely satisfies the condition for the maximum amount of received power Gmax. The safety factor Safe may be calculated at each time, in which case it is represented by the safety factor safe(t).

[0032] The command value calculation unit 146 calculates a power load command value as a command for the power load of the hydrogen production device 21 of the hydrogen production plant 10 based on the first control command calculation value calculated by the first control target command value calculation unit 141, the second control command calculation value calculated by the second control target command value calculation unit 141, and the safety factor safe calculated by the safety factor calculation unit 145.

[0033] For example, the hydrogen production planning device 41 may have scheduled the end of hydrogen production for a particular day at 6:00 PM. However, depending on the maximum amount of power received, the actual amount of hydrogen produced that day may not reach the scheduled end time. In such cases, the remaining extension time calculation unit 147 calculates the amount of extension needed to reach the scheduled end time of 6:00 PM.

[0034] The determination unit 155 determines whether or not the control calculation period has ended.

[0035] The output unit 160 has a command value output unit 161 and a display unit 162. The command value output unit 161 outputs the power load command value calculated by the command value calculation unit 146 to the hydrogen production device 21 of the hydrogen production plant 10. The display unit 162 displays the input information received by the input unit 110 or the calculation results stored in the calculation result storage unit 126.

[0036] The input unit 110 and the display unit 162 of the output unit 160 may be, for example, an interactive type that displays necessary instructions and information in response to a request.

[0037] Fig. 3 is a control block diagram showing the operation of the demand control device 100 according to the first embodiment. Fig. 3 shows the configurations of the first control target command value calculation unit 141 and the second control target command value control calculation unit 142 of the calculation unit 140 in the demand control device 100, and the relationship between these and the safety factor calculation unit 145 and the command value calculation unit 146.

[0038] The first control target command value calculation unit 141 has a first control target value calculation unit 141a and a first control calculation unit 141b.

[0039] The first control target value calculation unit 141a uses the maximum amount of received power Gmax over the division unit time width T to calculate a first control command calculation value, which is a first real-time control target value r1(t) at each calculation time t within the division unit time width T, using the following equation (1): Note that the first real-time control target value r1(t) is reset to zero (kWh) every time the division unit time width T ends. r1(t)=r1(t-Δt)+Gmax / N …(1)

[0040] The first control calculation unit 141b performs control calculation using the first real-time control target value r1(t) as a control target value and the actual received power value G(t) based on the output of the power meter 1a as a feedback signal. To this end, the first control calculation unit 141b includes a subtractor that subtracts the actual received power value G(t) from the first real-time control target value r1(t) to output a power deviation e1(t), and a PID calculation circuit that calculates a first control command calculation value SV1(t) by PID calculation using the following equations (2) and (3) based on the power deviation e1(t). The actual received power value G(t) is the integral of the received power from the start time of the division unit time span T to the calculation time t. Therefore, although not shown, the actual received power value G(t) is also reset to zero (kWh) each time the division unit time span T ends. The PID calculation circuit may be a PI calculation circuit if rapid response is not required compared to the characteristics of the hydrogen production plant 10. Furthermore, although FIG. 3 shows an example in which the first control calculation unit 141b has only a subtractor and a PID calculation circuit, it may also have functions of model control and advanced control. e1(t)=r1(t)-G(t) …(2)

[0041]

number

[0042] The second control target command value calculation unit 142 has a second control target value calculation unit 142a and a second control calculation unit 142b.

[0043] The second control target value calculation unit 142a calculates the second real-time control target value r2(t) at each calculation time t within the division unit time span T by using the hydrogen production planned value H(m) (m=1 to M) over the m-th division unit time, according to the following formula (4). Note that the second real-time control target value r2(t) is set to zero (Nm 3 ) is reset to r2(t)=r2(t-Δt)+H(m) / N …(4)

[0044] The second control calculation unit 142b performs control calculation using the second real-time control target value r2(t) as the control target value and the hydrogen production amount H(t) from the hydrogen production device 21 as a feedback signal. For this purpose, it has a subtractor that subtracts the hydrogen production amount H(t) from the second real-time control target value r2(t) to output the hydrogen production amount deviation e2(t), and a PID calculation circuit that calculates the second control command calculation value SV2(t) by PID calculation using the following equations (5) and (6) based on e2(t). The hydrogen production amount H(t) is the integral value of the received power from the start time of the division unit time width T to the calculation time t. For this reason, although not shown, the hydrogen production amount H(t) also returns to zero (Nm 3 ) The PID calculation circuit may be a PI calculation circuit when rapid response is not required compared to the characteristics of the hydrogen production plant 10. Furthermore, while FIG. 3 shows an example in which the second control calculation unit 142b has only a subtractor and a PID calculation circuit, it may also have functions of model control and advanced control. e2(t)=r2(t)-H(t) …(5)

[0045]

number

[0046] The safety factor calculation unit 145 may set the safety factor safe by an external input, or may calculate it as time-dependent using the following formula (7) for each divided unit time. safe(t)=n / N …(7)

[0047] As described above, the command value calculation unit 146 outputs the power load command value set(t) to the hydrogen production device 21 based on the first control command calculation value SV1(t), the second control command calculation value SV2(t), and the safety factor safe(t).

[0048] Below, several specific examples of the calculation of the power load command value set(t) to the hydrogen production device 21 will be shown.

[0049] In a first specific example, as shown in the following equations (8) and (9), an intermediate value SVtmp(t) is calculated by interpolating the first control command calculation value SV1(t) and the second control command calculation value SV2(t) according to the safety factor safe(t), and the minimum value of this intermediate value SVtmp(t) and the second control command calculation value SV2(t) is selected to calculate the power load command value set(t). Note that the interpolated intermediate value SVtmp(t) may also be used as the power load command value set(t). SVtmp(t) =SV1(t)+(1-safe(t))·(SV2(t)-SV1(t)) ...(8) set(t)=min(SVtmp(t),SV2(t)) …(9)

[0050] As a result, when the safety factor safe(t) is 1 (100%), the value of the intermediate value SVtmp(t) becomes the value of the first control command calculation value SV1(t), and even if the value of the second control command calculation value command value SV2(t) calculated by the second control target command value calculation unit 142 is large, the value of the power load command value set(t) is limited to the value of the first control command calculation value SV1(t), and operation follows the first control command calculation value SV1(t). Also, when the value of the second control command calculation value command value SV2(t) calculated by the second control target command value calculation unit 142 is small, operation follows the second control command calculation value command value SV2(t), and the amount of hydrogen produced is as planned.

[0051] In the second specific example, the second real-time control target value r2(t) is calculated using the shortage Hlack(t) with respect to the hydrogen production planned value H(n) over the n-th division unit time (for example, 30 minutes). At this time, the second real-time control target value r2(t) is calculated by dividing the second real-time control target value r2(t) by 0 Nm per division unit time. 3 However, the shortage amount Hlack(t) is not reset for each divided unit time, but is reset at the end of the hydrogen production plan for one day. The following equation (10) shows, for example, a case in which a premium is added to the hydrogen production plan value for the next divided unit time width T (for example, 30 minutes). r2(t)=r2(t-Δt)+(H(t)+Hlack(t)) / N …(10)

[0052] Alternatively, in order to minimize changes to the hydrogen production plan, the shortage Hlack(t) may be eliminated by the time the hydrogen production plan is completed. In this case, the second real-time control target value r2(t) is set to the time T toEnd (t) can be used to calculate the following equation (11). r2(t) =r2(t-Δt)+H(t) / N+Hlack(t) / T toEnd (t) …(11)

[0053] FIG. 4 is a block diagram showing the configuration of a demand control device 100a according to a modification of the first embodiment.

[0054] The third specific example is a variation of the first embodiment, and the calculation unit 140a has a calculation unit first control target upper limit value calculation unit 143 instead of the first control target command value 141 of the calculation unit 140, and a calculation unit second control target upper limit value calculation unit 144 instead of the second control target command value 142.

[0055] In the calculation unit 140a, the first control target upper limit value calculation unit 143 calculates the upper limit value SVmax(t) of the control command value to the hydrogen production device 21 using the maximum amount of received power Gmax, the actual value of received power G(t), and the actual value of instantaneous PV power generation power PV(t) at step n (time t) within the division unit time T, so as to limit the upper limit of the command value to the hydrogen production plant 10. The command value calculation unit 146 calculates the power load command value set(t) based on the intermediate value SVtmp(t), which is an interpolated value between the first control command calculation value and the second control command calculation value, as in the following formulas (13) and (14). SVmax(t)=(Gmax-G(t)) / (Nn)+PV(t) …(12) SVtmp(t) =SV1(t)+(1-safe(t))·(SV2(t)-SV1(t)) …(13)

[0056] set(t) =min(min(SVtmp(t),SV2(t)),SVmax(t)) …(14)

[0057] When the safety factor safe(t) is changed according to the power load of the hydrogen production plant 10, if the amount of hydrogen production is significantly less than the planned hydrogen production value, there is a possibility that the value of the power load command value set(t) will always be the value of the second control command calculation value command value SV2(t). In other words, there is a possibility that the condition of the amount of received power, which is the first control target, will not be met. This specific example solves this problem and makes it possible to meet the condition of the amount of received power, which is the first control target.

[0058] The command value calculation unit 146 may calculate the power load command value set(t) as shown in the following equation (15) using the upper limit value SVmax(t) of the control command value for the hydrogen production device 21 calculated by the first control target upper limit value calculation unit 143 and the safety factor safe. In this case, the value of the safety factor safe(t) is greater than 0 and less than or equal to 1, for example, a value greater than or equal to 0.1 and less than or equal to 1.0. set(t)=min(SVmax(t)·safe(t),SV2(t)) …(15)

[0059] FIG. 5 is a flowchart showing the procedure of the demand control method according to the first embodiment.

[0060] The demand control method includes a reading step S10, a control step S20, and an extension calculation step S30.

[0061] The reading step S10 includes reading of control parameters (step S11), reading of a hydrogen production plan including planned hydrogen production values ​​(step S12), and reading of conditions for renewable energy capacity and maximum amount of received power (step S13), all of which are performed by the input unit 110. Note that although steps S11 to S13 are described in this order in Fig. 5, the order of steps S11 to S13 does not matter, and they may also be performed in parallel.

[0062] In the control step S20 following the reading step S10, first, the input unit 110 reads each performance value (step S21).

[0063] In the control step S20, calculations are repeatedly performed for each calculation step width Δt between reading each actual value (step S21) and the step of determining the end of the final control period (S26).

[0064] After reading each actual value (step S21), the first control target command value calculation unit 141 calculates a first control target command calculation value SV1(t) (step S22), and the second control target command value calculation unit 142 calculates a second control target command calculation value SV2(t) (step S23). Here, steps S22 and S23 can be performed in any order, or can be performed in parallel with each other. Next, the safety factor calculation unit 145 calculates the safety factor safe(t) (step S24). Next, the command value calculation unit 146 calculates the power load command value set(t) based on the first control target command calculation value SV1(t), the second control target command calculation value SV2(t), and the safety factor safe(t), and the output unit 160 outputs this as a command signal to the hydrogen production device 21 of the hydrogen production plant 10 (step S25).

[0065] Next, the determination unit 155 determines whether the control period has ended (step S26). Here, the control period is a period during which the demand control device 100 continuously performs control, and the control period is, for example, one year or several months, and the value is read by the input unit 110 when the control parameters are read in step S11.

[0066] If the determination unit 155 does not determine that the control period has ended (NO in step S26), steps S21 to S26 are repeated. If the determination unit 155 determines that the control period has ended (YES in step S26), the control step S20 is ended.

[0067] Although not shown in FIG. 5, in step S26, the determination unit 155 determines whether the calculation step is the last step of the division unit time width T. If the determination unit 155 determines that the calculation step is the last step of the division unit time width T, it instructs the first control target command value calculation unit 141 and the second control target command value control calculation unit 142 to set the first real-time control target value r1(t) to zero (kWh) and the second real-time control target value r2(t) to zero (Nm 3 ) to reset each of them.

[0068] The extension calculation step S30 is executed in parallel with the control step S20.

[0069] In the extension calculation step S30, in the repeated calculation of the control step S20, each time a division unit time width T ends, the extension remaining time calculation unit 147 accumulates the hydrogen production amount H(t) obtained in that division unit time width T and predicts the hydrogen production amount that will be obtained by the scheduled end time of that day (step S31).

[0070] Next, the extended remaining time calculation unit 147 compares the total value of the hydrogen production plan value H(m) (m = 1 to M) for the divided unit times up to the mth, and determines whether there is a prospect of achieving the required amount of hydrogen production for that day by the scheduled end time of that day (step S32).

[0071] If the extension remaining time calculation unit 147 determines that there is a possibility that the required amount of hydrogen production will be achieved by the scheduled end time of the day (YES in step S32), steps S31 and S32 are repeated.

[0072] If the extension remaining time calculation unit 147 determines that the required amount of hydrogen production is unlikely to be achieved by the scheduled end time of the day (step S32 NO), the extension remaining time calculation unit 147 performs an end time extension calculation (step S33). That is, it calculates the end time extension time, such as the need to extend the end time from the scheduled end time of 6:00 PM for that day and produce hydrogen for an additional three hours.

[0073] As described above, according to this embodiment, the amount of hydrogen produced by the hydrogen production plant 10 can be secured by effectively utilizing renewable energy generated electricity while minimizing the excess of the maximum amount of power received Gmax, which is a condition for the power to be received and sent.

[0074] [Second embodiment] 6 is a block diagram showing the configuration of a demand control device 100b according to a second embodiment. This embodiment is a modification of the first embodiment.

[0075] In this embodiment, the memory unit 120b includes an actual value memory unit 121, a maximum received power amount memory unit 122, a target power memory unit 123, a control parameter memory unit 124, and a hydrogen production plan memory unit 125, as well as a margin power memory unit 127, a PV power generation amount predicted value memory unit 128, a weather information memory unit 129, and a penalty allowance memory unit 130.

[0076] The input unit 110 also accepts, as external inputs, a power value Margin that is a margin for the maximum amount of received power Gmax, the actual value and predicted value of the PV power generation amount which is the power generation amount of the renewable energy power generation device 11, weather information for the installation location of the renewable energy power generation device 11, and an allowable amount that may exceed the maximum amount of received power Gmax.

[0077] The margin power storage unit 127 stores the power value of the margin Margin for the maximum amount of received power Gmax read by the input unit 110. The margin power value may be stored as an absolute value in kWh or as a ratio.

[0078] The PV power generation amount predicted value storage unit 128 stores a predicted value related to the PV power generation amount read by the input unit 110. The predicted value may be not only a PV power generation amount predicted value for each divided unit time but also information on the confidence interval of the predicted value. Although an example has been described in which the PV power generation amount predicted value or the confidence interval information is read from the input unit 110, this is not limiting. For example, the predicted value may be calculated from past actual PV power generation values. Alternatively, the confidence interval information may be calculated by assuming that the PV power generation amount error follows a normal distribution, but is not limited to this.

[0079] The weather information storage unit 129 stores the weather information read by the input unit 110. The weather information includes, for example, past weather information such as sunny, cloudy, and rainy, time-series data of actual PV power generation amount and predicted PV power generation amount, and current weather information.

[0080] The penalty allowance storage unit 130 stores an allowable amount that can exceed the maximum amount of received power Gmax read by the input unit 110. The allowable amount includes an excess power amount (Excess), the number of times of exceeding, or a penalty amount due to an exceeding amount.

[0081] The safety factor calculation unit 145 uses the margin power Margin from the maximum received power Gmax stored in the margin power memory unit 127, the PV power generation prediction value and confidence interval information stored in the PV power generation prediction value memory unit 128, the past PV power generation actual values, PV power generation prediction values ​​and weather information stored in the weather information memory unit 129, and the excess power amount Excess that is allowed to exceed the maximum received power Gmax stored in the penalty allowance memory unit 130 to calculate the safety factor safe, which represents the degree of compliance with the first control target, as shown in the following specific example.

[0082] At time t, the first control target command value calculation unit 141 calculates the first real-time control target value r1(t) for each calculation period Δt using the maximum receiving power amount Gmax during the division unit time width T at the current time and the margin power Margin from the maximum receiving power amount Gmax using the following equation (16). r1(t)=r1(t-Δt)+(Gmax-Margin) / N …(16)

[0083] In this way, by controlling the first real-time control target value r1(t) as a target, which is determined in advance with a certain margin taken into account for the maximum amount of received power, the risk of exceeding the maximum amount of received power Gmax can be further reduced.

[0084] Furthermore, when the penalty allowable amount storage unit 130 stores an excess power amount Excess that is allowed to exceed the maximum amount of received power Gmax, the first real-time control target value r1(t) may be calculated by the following equation (17). r1(t) =r1(t-Δt)+(Gmax-Margin+Excess) / N …(17)

[0085] The safety factor calculation unit 145 may calculate the safety factor safe using the PV power generation prediction value PVpre(t) and the error amount PVpre1σ(t) (hereinafter referred to as confidence interval information) where the prediction error of the PV power generation amount is ±σ, as shown in the following equation (18). For example, when the PV power generation prediction value PVpre(t) is 1000 kWh and the confidence interval information PVpre1σ(t) is 200 kW, the safety factor safe(t) is 80%. safe=(PVpre(t)-PVpre1σ(t)) / PVpre(t) …(18)

[0086] If the ratio of the confidence interval information PVpre1σ(t) to the predicted PV power generation value PVpre(t) is small, the safety factor safe will also be small, and if the ratio of the confidence interval information PVpre1σ(t) is large, the safety factor safe will also be large. In other words, the larger the ratio of the confidence interval information PVpre1σ(t), the greater the possibility that the error in the predicted PV power generation value PVpre(t) will be large, so the safety factor safe can be set higher. This makes it possible to reduce the risk of exceeding the maximum received power amount Gmax even if the predicted PV power generation value PVpre(t) is significantly off.

[0087] Additionally, by using past actual and predicted PV power generation values ​​and weather information, it is possible to further reduce the risk of exceeding the maximum received power Gmax. For example, past time-series data that matches the current weather information is extracted, and the PV power generation error rate is calculated from the extracted past time-series data, the actual PV power generation value and the predicted PV power generation value PVpre(t). By using this PV power generation error PVerror(t) (greater than or equal to 0 and less than or equal to 1) to calculate the safety factor safe as shown in the following equation (19), it becomes possible to take into account the error in PV power generation based on past weather information. safe(t) =[(PVpre(t)-PVpre1σ(t)) / PVpre(t)] PV error (t) … (19)

[0088] In the safety factor calculation unit 145, the PV power generation predicted value PVpre(t) for the division unit time at the current time and the PV power generation actual value PVkWh(t) up to n steps within the division unit time width T at the current time may be used to calculate the safety factor safe in real time while taking into account the error from the predicted value as shown in the following equation (20). safe(t)=PVkWh(t) / [(PVpre(t)·(n / N)] …(20)

[0089] In addition, the information stored in the penalty allowance memory unit 130 is not the excess power amount (Excess) that may exceed the maximum received power amount Gmax, but the number of times that the maximum received power amount Gmax may be exceeded, or, in the case of the penalty amount due to an exceedance, a safety factor corresponding to that is set.

[0090] In the above example, the safety factor calculation unit 145 calculates the safety factor safe using the PV power generation prediction value PVpre(t) and the confidence interval information PVpre1σ(t). In this case, if the confidence interval information PVpre1σ(t) is greater than the PV power generation prediction value PVpre(t) or if the confidence interval information PVpre1σ(t) is erroneously a negative value, it is possible that the safety factor deviates from the range of 0 to 1 (0% to 100%). In this case, upper and lower limits may be set, or, for example, a sigmoid function may be used to convert from 0 to 1 (0% to 100%). Note that any function other than the sigmoid function may be used as long as it converts from 0% to 100%.

[0091] According to this embodiment, in addition to the effects of the first embodiment, the risk of exceeding the maximum amount of received power due to various factors can be reduced by taking into account a margin of power so as not to exceed the maximum amount of received power Gmax and by using a predicted PV power generation amount and weather information. Furthermore, if there is an allowable penalty, operation can be performed taking this into consideration. The penalty allowable amount storage unit 130 may also store a "time period" during which a penalty is allowed, rather than a "tolerance." In this case, during a time period during which a penalty is allowed, the allowable amount of the maximum amount of received power may be increased (or there may be no limit on the maximum amount of received power), and a power load command value for the hydrogen production device 21 is calculated according to this allowable amount.

[0092] [Third embodiment] 7 is a block diagram showing the configuration of a hydrogen production system 40c according to the third embodiment. This embodiment is a modification of the first embodiment, and differs in that the hydrogen production plant 10c further includes a load facility 22 that consumes electric power. This difference is reflected in the demand control device 100c. In other respects, this embodiment is similar to the first embodiment.

[0093] FIG. 8 is a block diagram showing the configuration of a demand control device 100c according to the third embodiment.

[0094] The storage unit 120 of the demand control device 100c further includes an equipment model storage unit 131 that stores a load equipment model for predicting the power consumption of the load equipment 22. The data stored in the equipment model storage unit 131 is received by the input unit 110. In addition, the calculation unit 140 of the demand control device 100c further includes a load equipment power consumption prediction unit 148.

[0095] The load equipment model is not limited to a prediction method as long as it predicts the power consumption of the load equipment 22 in the next division unit time width T. For example, it may be an ARMA (autoregressive moving average model), which is one of the time series analysis methods, or it may be a deep learning method such as a neural network or a random forest using a tree structure.

[0096] The load equipment power consumption prediction unit 148 uses the load equipment model stored in the equipment model memory unit 131 to predict the power consumption (load equipment power consumption) Laod(t) of the load equipment 22 in the next division unit time width T using the actual values ​​stored in the actual value memory unit 121 that are required for the prediction calculation.

[0097] The first control target command value calculation unit 141 calculates a control command value for the hydrogen production device 21 using the predicted value of the load equipment power consumption calculated by the load equipment power consumption prediction unit 148 so that the actual value G(t) of the amount of received power matches the maximum amount of received power Gmax. At this time, the first real-time control target value r1(t) is calculated by the following equation (21) using the load equipment power consumption Laod(t) in the next division unit time width T.

[0098] r1(t)=r1(t-Δt)+(Gmax-Load(t)) / N …(21)

[0099] Thus, in this embodiment, in addition to the effects of the first embodiment, if there is load equipment 22 other than the hydrogen production device 21 within the hydrogen production plant 10c, the risk of exceeding the maximum received power amount Gmax due to fluctuations in the power consumption of the load equipment 22 can be reduced by predicting the power consumption of the load equipment 22.

[0100] [Fourth embodiment] FIG. 9 is a block diagram showing the configuration of a hydrogen production system 40d according to the fourth embodiment.

[0101] This embodiment is a modification of the first embodiment and further includes a power planning device 42. The power planning device 42 is a device that creates a power exchange plan with the power grid, such as a power sales plan in the hydrogen production plant 10, and the target power is the amount of power sold per divided unit time. Alternatively, the power planning device 42 may be a device that creates a plan with the instantaneous value of power sales or the instantaneous value of power received as the target power, as a device aimed at stabilizing the power grid 1. Alternatively, the hydrogen production plant 10 may be linked to an external power storage facility, and the target power may be a power specified by the power storage facility. In other words, the power planning device 42 is not limited to these, as long as it is a device that creates a plan based on a power-related target.

[0102] FIG. 10 is a block diagram showing the configuration of a demand control device 100d according to the fourth embodiment.

[0103] The storage unit 120d of the demand control device 100d has a target power storage unit 123 instead of the maximum received power amount storage unit 122.

[0104] The demand control device 100d receives the target power from the power planning device 42 and stores it in the target power storage unit 123. The calculation unit 140 calculates a command value for the hydrogen production device 21 to achieve the hydrogen production plan set by the hydrogen production planning device 41 as much as possible while adhering to this target power.

[0105] At time t, the first control target command value calculation unit 141 calculates the first real-time control target value r1(t) in each calculation cycle Δt using the amount of power sold Gs(t) of the current division unit time by the following equation (22). Note that the amount of power sold Gs(t) of the division unit time is a negative value. r1(t)=r1(t-Δt)+Gs(t) / N …(22)

[0106] On the other hand, when the target power is the instantaneous value Gsinstant(t) of the power sale at time t in the target power storage unit 123, the first real-time control target value r1(t) in each calculation cycle is calculated by the following equation (23). r1(t)=Gsinstant(t) …(23)

[0107] In the case of the instantaneous value of the power sold Gsinstant(t), the control command value SV1(t) to the hydrogen production device 21 is calculated using the following equations (24) and (25) so that the instantaneous actual value of the power sold g(t) matches the first real-time control target value r1(t). Note that the same calculation can be performed when the target power is the instantaneous value of the received power. e1(t)=r1(t)-g(t) …(24)

[0108]

number

[0109] According to this embodiment, in addition to the effects of the first embodiment, when there is an external power command (amount of power sold, instantaneous value of power sold, instantaneous value of power received), it is possible to achieve the second control target as much as possible while adhering to the target power.

[0110] [Fifth embodiment] Fig. 11 is a block diagram showing the configuration of a hydrogen production system 40e according to the fifth embodiment, and Fig. 12 is a block diagram showing the configuration of a demand control device 100e according to the fifth embodiment.

[0111] This embodiment is a modification of the first, third, and fourth embodiments, and as shown in Fig. 12, in a hydrogen production system 40e, a hydrogen production plant 10e has a load facility 22 similar to that of the third embodiment. The hydrogen production system 40e also has a power planning device 42e.

[0112] Here, the power planning device 42e is a device that aims to stabilize the power system 1, similar to the power planning device 42 in the fourth embodiment, but the power planning device 42e in this embodiment is characterized in that it formulates a plan in which the instantaneous value of the power to be sold or the instantaneous value of the power received is set as the target power.

[0113] As shown in FIG. 13 , the demand control device 100e has a load equipment power consumption prediction unit 148 similar to that of the third embodiment, and further has a load equipment start / stop plan confirmation unit 149. The load equipment start / stop plan confirmation unit 149 confirms the start and stop timing of the load equipment 22 that occurs in relation to the operation plan of the hydrogen production equipment 21 planned by the hydrogen production planning device 41, and outputs a change command related to the start and / or stop (start / stop) of the load equipment 22 as necessary. A command value output unit 161 of the output unit 160 outputs the changed start / stop command to the load equipment 22. The change command related to the start / stop is, for example, a change command for the start / stop timing or a change command for the number of auxiliary equipment to be started / stopped.

[0114] <Explanation of action and effect> The load equipment 22 has auxiliary equipment, such as a compressor that increases the pressure of hydrogen, whose start / stop operation greatly affects fluctuations in its power consumption. The load equipment 22 also has a control device that receives a change command regarding start / stop from the demand control device 100e and operates in accordance with the command.

[0115] The load equipment start / stop plan confirmation unit 149 confirms and monitors whether the start / stop of the load equipment 22 will affect compliance with the power transfer conditions with the power grid 1 stored in the maximum received power amount storage unit 122, for example, whether the instantaneous value of the power sale or the instantaneous value of the power reception falls within a time period in which the target power must be maintained. If there is a possibility that the start / stop of the load equipment 22 will affect compliance with the power transfer conditions with the power grid 1, the load equipment start / stop plan confirmation unit 149 outputs an instruction to avoid the effect. For example, if the instantaneous value of the power sale or the instantaneous value of the power reception falls within a time period in which the maximum received power must be maintained, the start / stop timing plan is corrected to avoid start / stop during this time period. The command value output unit 161 outputs the result as a command timing to the load equipment 22.

[0116] According to this embodiment, the timing of the command to start / stop the load equipment 22 is set to avoid the time when the power transfer conditions must be observed, so that the power transfer conditions can be observed even when the power consumption fluctuates significantly due to the start / stop of the load equipment 22. If the start / stop of the load equipment 22 affects the hydrogen production plan, the hydrogen production plan of the hydrogen production planning device 41 may be corrected according to the command timing. Furthermore, the demand control device 100e may calculate the start / stop timing of the load equipment 22 and notify the operator of the load equipment of the command timing by outputting it to a monitoring screen or by email.

[0117] [Sixth embodiment] 13 is a block diagram showing the configuration of a demand control device 100f according to a sixth embodiment. This embodiment is a modification of the first embodiment.

[0118] The storage unit 120f further includes an equipment model storage unit 131 that stores a model of each piece of equipment in the hydrogen production plant 10. The calculation unit 140f further includes an operating cost calculation unit 150 and an optimization calculation unit 151. The output unit 160 further includes an optimization variable output unit 163. The input unit 110 further receives the renewable energy power generation actual value of the renewable energy power generation device 11. The actual value storage unit 121f further stores and stores the renewable energy power generation actual value received by the input unit 110. The renewable energy power generation actual value stored in the actual value storage unit 121f is, for example, time-series actual data for one year.

[0119] The operating cost calculation unit 150 performs a one-year simulation using the renewable energy power generation data stored in the actual value storage unit 121f, the model of the hydrogen production device 21 stored in the equipment model storage unit 131, and the control command values ​​for the hydrogen production device 21 calculated by the command value calculation unit 146, and calculates the operating costs of the hydrogen production plant 10. The operating costs are calculated based on electricity rates, hydrogen sales fees, etc. The operating costs may also be calculated taking into account capital expenditures for the equipment, etc.

[0120] The optimization calculation unit 151 creates data by multiplying the renewable energy power generation data actual value stored in the actual value storage unit 121f by a constant as a change in renewable energy capacity, changes the maximum received power amount Gmax stored in the maximum received power amount storage unit 122, and calculates the renewable energy capacity and the maximum received power amount that minimize the operating cost. Note that the optimization calculation unit 151 may optimize at least one value of the conditions of the capacity of the renewable energy power generation device 11 and the maximum received power amount that minimize the operating cost.

[0121] The optimization variable output unit 163 outputs the renewable energy capacity and the maximum amount of received power that minimize the operating cost calculated by the optimization calculation unit 151.

[0122] FIG. 14 is a flowchart showing the procedure of a demand control method according to the sixth embodiment.

[0123] The demand control method in this embodiment includes a reading step S10, a control step S20, and an optimization step S40. The reading step S10 and the control step S20 are the same as those in the first embodiment, so their explanations will be omitted, and only the optimization step S40 will be explained.

[0124] Every time it is determined that the control period has ended in control period end determination step S26 of control step S20 (YES in step S26), the operating cost calculation unit 150 calculates the operating cost (step S41). Next, the operating cost calculation unit 150 determines whether the operating cost is minimum or not (step S42).

[0125] If the operating cost is not determined to be the minimum (NO in step S42), the process returns to step S13, new conditions for the renewable energy capacity and the maximum amount of received power are read, and step S20, step S41, and step S42 are repeated.

[0126] If it is determined that the operating cost is minimum (YES in step S42), the optimization variable output unit 163 outputs the renewable energy capacity and the maximum amount of received power that minimize the operating cost.

[0127] While the above has quoted Fig. 14 and shown an example of reading new conditions for the renewable energy capacity and the maximum amount of received power as an external input, the optimization calculation unit 151 shown in Fig. 13 may generate new conditions for the renewable energy capacity and the maximum amount of received power without relying on an external input. Alternatively, the optimization calculation unit 151 may derive optimal solutions for the renewable energy capacity and the maximum amount of received power without relying on iterative calculations.

[0128] According to this embodiment, by calculating control command values ​​for the hydrogen production device so as to achieve the hydrogen production plan as much as possible while adhering to the maximum amount of received power, it is possible to calculate the conditions for the renewable energy capacity and maximum amount of received power that minimize operating costs. For example, it is possible to determine the optimal renewable energy capacity when constructing a hydrogen production plant. Alternatively, it is possible to determine the optimal maximum amount of received power even in an operating hydrogen production plant.

[0129] According to the embodiment described above, it is possible to provide a demand control device and a demand control method that can suppress the amount of excess power over the contracted power in a hydrogen production plant that uses power generated by renewable energy.

[0130] [Other embodiments] Although several embodiments of the present invention have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. Furthermore, since the embodiments are not mutually exclusive, features of multiple or all of the embodiments may be combined. These novel embodiments may be embodied in various other forms, and various omissions, substitutions, and modifications may be made without departing from the spirit of the invention. These embodiments and their modifications are within the scope and spirit of the invention, and are included in the scope of the invention and its equivalents as defined in the claims. [Explanation of symbols]

[0131] 1...power system, 1a...power meter for trading, 10, 10c...hydrogen production plant, 11...renewable energy power generation equipment (PV), 21...hydrogen production equipment, 22...load equipment, 31...in-house bus, 40, 40c, 40d...hydrogen production system, 41...hydrogen production planning device, 42...power planning device, 100, 100a, 100b, 100c, 100d, 100e, 100f...demand control device, 110...input unit, 120...memory unit, 121...actual value memory unit, 122...maximum received power amount memory unit, 123...target power memory unit, 124...control parameter memory unit, 125...hydrogen production plan memory unit, 126...calculation result memory unit, 127...margin power memory unit, 128...PV power generation amount predicted value memory unit, 129...weather information memory unit, 130... Penalty allowance memory unit, 131...equipment model memory unit, 140, 140a...calculation unit, 141...first control target command value calculation unit, 141a...first control target value calculation unit, 141b...first control calculation unit, 142...second control target command value control calculation unit, 142a...second control target value calculation unit, 142b...second control calculation unit, 143...first control target upper limit value calculation unit, 144...first control target upper limit value calculation unit, 145...safety factor calculation unit, 146...command value calculation unit, 147...extension remaining time calculation unit, 148...load equipment power consumption prediction unit, 149...load equipment start / stop plan confirmation unit, 150...operation cost calculation unit, 151...optimization calculation unit, 155...determination unit, 160...output unit, 161...command value output unit, 162...display unit, 163...optimization variable output unit

Claims

1. A demand control device for controlling a power load of a hydrogen production plant that is connected to an external power grid and includes a renewable energy power generation device, a hydrogen production device to which a hydrogen production plan value is assigned, and a power meter for trade that measures power exchanged with the power grid, an input unit that receives input information including the planned hydrogen production value, the actual value of the power load of the hydrogen production device, the actual value of the power transfer measured by the power meter, and conditions related to the power transfer, including a maximum amount of power that can be received; a storage unit that stores the input information received by the input unit; a first control target command value calculation unit that calculates a first control command calculation value by control calculation using a predetermined amount of power as a target value and an actual value of the transferred power as a feedback signal; a second control target command value calculation unit that calculates a second control command calculation value by control calculation using the planned hydrogen production value as a target value and an actual value of the amount of hydrogen produced by the hydrogen production device as a feedback signal; a safety factor calculation unit that calculates a safety factor that defines the degree of compliance with the condition of the maximum amount of received power; a command value calculation unit that calculates a power load command value for the hydrogen production device based on the first control command calculation value, the second control command calculation value, and the safety factor; A demand control device comprising:

2. the safety factor has a value in the range of greater than 0 and less than or equal to 1, 2. The demand control device according to claim 1, wherein the command value calculation unit calculates the power load command value based on an intermediate value that is an interpolated value between the first control command calculation value and the second control command calculation value based on the safety factor.

3. 3. The demand control device according to claim 2, wherein the command value calculation unit further compares the calculated value with the second control command calculation value and outputs the smaller value as the power load command value.

4. the storage unit stores a power load command upper limit value that is an upper limit value of the power load command value, When the calculated power load command value exceeds the power load command upper limit value, the command value calculation unit outputs the power load command upper limit value as the power load command value instead of the calculated power load command value.

2. The demand control device according to claim 1, wherein the demand control device is a power supply device.

5. the storage unit stores a power load command upper limit value that is an upper limit value of the power load command value, the command value calculation unit outputs, as the power load command value, the smaller of a value obtained by multiplying the power load command upper limit value by the safety factor and the second control command calculation value.

3. The demand control device according to claim 2.

6. the second control target command value calculation unit adds a shortage with respect to the hydrogen production planned value to a subsequent control target value; 2. The demand control device according to claim 1, wherein the demand control device is a power supply device.

7. the input unit receives, as a further input, power corresponding to a margin from the maximum amount of received power; the first control target command value calculation unit calculates the first control command calculation value using the margin of power; 2. The demand control device according to claim 1, wherein the demand control device is a power supply device.

8. the input unit accepts, as a further input, a predicted value or confidence interval information of the predicted value regarding the amount of PV power generation by the renewable energy power generation device; the safety rate calculation unit calculates the safety rate using the predicted value or the confidence interval information.

2. The demand control device according to claim 1, wherein the demand control device is a power supply device.

9. the hydrogen production plant further includes load equipment that consumes electricity; the storage unit further includes a load equipment model storage unit that stores a load equipment model for predicting the power consumption of the load equipment; The demand control device includes: a load equipment power consumption prediction unit that predicts the power consumption of the load equipment using the load equipment model; the command value calculation unit calculates the power load command value to the hydrogen production device using a predicted value of power consumption of the load equipment.

2. The demand control device according to claim 1, wherein the demand control device is a power supply device.

10. The demand control device according to claim 9, further comprising a load equipment start / stop plan confirmation unit that outputs instructions to avoid the impact of starting or stopping the load equipment that is likely to have an impact on compliance with the power transfer conditions with the power grid.

11. The demand control device described in claim 1, further comprising an extension remaining time calculation unit that calculates an extension time for the scheduled end time when the actual value of the hydrogen production amount does not reach the hydrogen production planned value even when the scheduled end time for the day is reached.

12. an operating cost calculation unit that calculates the operating cost of the hydrogen production plant for a predetermined period; an optimization calculation unit that optimizes at least one value of the capacity of the renewable energy power generation device and the maximum amount of received power, so that the operating cost is minimized; 2. The demand control device according to claim 1, further comprising:

13. A hydrogen production plant according to any one of claims 1 to 12; The demand control device according to any one of claims 1 to 12; A hydrogen production system comprising:

14. A demand control method for controlling a power load of a hydrogen production plant that is connected to an external power grid and includes a renewable energy power generation device, a hydrogen production device to which a hydrogen production plan value is assigned, and a power meter for trade that measures power exchanged with the power grid, the method comprising: an input unit receiving input information including the hydrogen production planned value, the actual value of the power load of the hydrogen production device, the actual value of the power transfer measured by the power market meter, and a maximum amount of power that can be received as a condition for the power transfer, and a storage unit storing the input information; a step in which a first control target command value calculation unit outputs a first control command calculation value by control calculation using a predetermined amount of power as a target value and an actual value of the transferred power as a feedback signal; a step in which a second control target command value calculation unit outputs a second control command calculation value by control calculation using the hydrogen production planned value as a target value and an actual value of the amount of hydrogen produced by the hydrogen production device as a feedback signal; a step in which a safety factor calculation unit calculates a safety factor that specifies a degree of compliance with the condition of the maximum amount of received power; a command value calculation unit calculating an electric power load command value for the hydrogen production device based on the first control command calculation value, the second control command calculation value, and the safety factor; A demand control method comprising:

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