Autonomous operation system and program

Abstract

To preferably control the charge rate of a storage battery in a self-sustained operation system.SOLUTION: The self-sustained operation system is capable of a self-sustained operation dependent from a power system, and includes: a power storage device; at least one of a fuel battery and an internal combustion power generation facility; and a load facility. The self-sustained operation system sets a target charge rate as a target value of the charge rate of the power storage device on the basis of the power demand of the load facility and the charge rate of the power storage device in a predetermined period of time of a day.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an autonomous operation system and a program. [Background technology]

[0002] Patent document 1 states, "Due to the principles of how fuel cells generate power, the amount of power they generate cannot be changed suddenly. Therefore, even if load following control is applied to fuel cells, if the power consumption of the load increases suddenly, the output power of the fuel cell will be insufficient compared to the power consumption of the load" (paragraph 0004). Patent document 2 states that "the amount of hydrogen produced and stored, the amount of charge in the storage battery, and the amount of power generated by the fuel cell are controlled based on the results of a comparison between the predicted and actual surplus power values ​​and the results of a comparison between the charging rate of the storage battery and a first set value" (Claim 1). Patent Document 3 states, "A power supply system comprising a fuel cell capable of generating power and having a load following function for generating power as needed, and..." (Claim 1). [Prior art document] [Patent documents] [Patent Document 1] JP 2013-74757 A [Patent Document 2] JP 2020-54085 A [Patent Document 3] JP 2015-226353 A Summary of the Invention [Problem to be solved by the invention]

[0003] In an isolated operation system, it is preferable that the charging rate of the storage battery is appropriately controlled. [Means for solving the problem]

[0004] In a first aspect of the present invention, there is provided an independent operation system. The independent operation system is capable of independent operation independent of a power grid and includes a power storage device, at least one of a fuel cell and an internal combustion power generation device, and a load device. The independent operation system sets a target charging rate, which is a target value of the charging rate of the power storage device, based on the relationship between the power demand of the load device and the charging rate of the power storage device during a predetermined period of one day.

[0005] The target charging rate may change in response to a change in the power demand. The isolated operation system may set the target charging rate based on a predetermined rate of change of the target charging rate in response to a change in the power demand.

[0006] The isolated operation system may set the target charging rate higher than a predetermined rate of change of the target charging rate.

[0007] The isolated operation system may set the target charging rate lower than a predetermined rate of change of the target charging rate.

[0008] The power storage device may have a storage unit that stores a relationship between the power demand and the target charging rate. The independent operation system may set the charging rate of the power storage device based on the relationship between the power demand and the target charging rate stored in the storage unit.

[0009] The isolated operation system may control the charging rate of the power storage device based on the type of the power storage device.

[0010] The autonomous operation system may set the target charging rate at the start of a predetermined period in a day to be higher than the target charging rate at a predetermined time before the start of the predetermined period.

[0011] The isolated operation system may set the target charging rate at the end of a predetermined period in a day to be lower than the target charging rate at a predetermined time before the end of the predetermined period.

[0012] The autonomous operation system may further include a renewable energy power generation facility. The autonomous operation system may set a target charging rate based on a relationship between a limited power obtained by subtracting a generated power output from the renewable energy power generation facility from a demand power during a predetermined period and the target charging rate.

[0013] In a second aspect of the present invention, there is provided a program that causes a computer to function as an autonomous operation system.

[0014] The above summary of the invention does not list all of the necessary features of the present invention. Also, subcombinations of these features may also be inventions. [Brief description of the drawings]

[0015] [Figure 1] FIG. 1 is a diagram illustrating an example of an independent operation system 100 according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a diagram showing an example of control of a frequency f of the isolated operation system 100. [Figure 3A] 1 is a block diagram showing an example of output control of a fuel cell or the like 30 when an independent operation system 100 is operating independently from a power grid 200. FIG. [Figure 3B] 4 is a block diagram showing an example of control for deriving a corrected stored power Pa from a charging rate S. FIG. [Figure 4] This is a conceptual diagram showing an example of the changes over time in one day of the demand power Pdm of the load equipment 40, the output power Pf of the fuel cell etc. 30, and the generated power Pg of the renewable energy power generation equipment 10 when the independent operation system 100 is operating independently from the power grid 200. [Diagram 5] 4 is a diagram showing an example of a relationship between a power demand Pdm and a target charging rate Sd of a power storage device 20. FIG. [Figure 6]This figure shows an example of the changes over time in the demand power Pdm of the load equipment 40, the output power Pf of the fuel cell etc. 30, the generated power Pg of the renewable energy power generation equipment 10, the discharge power Pd of the power storage device 20 or the charging power Pc to the power storage device 20, and the charging rate S of the power storage device 20 during a predetermined period of one day when the independent operation system 100 is operating independently from the power grid 200. [Figure 7] This figure shows a first comparative example of the changes over time in the demand power Pdm, the output power Pf, the generated power Pg, the discharged power Pd or the charged power Pc, and the charging rate S in one day when the independent operation system 100 is operating independently from the power grid 200. [Figure 8] This figure shows an example of the changes over time in the demand power Pdm of the load equipment 40, the output power Pf of the fuel cell etc. 30, the discharge power Pd of the power storage device 20 or the charging power Pc to the power storage device 20, and the charging rate S of the power storage device 20 during a predetermined period of one day when the independent operation system 100 is operating independently from the power grid 200. [Figure 9] This figure shows a second comparative example of the changes over time in the demand power Pdm, the output power Pf, the discharge power Pd or the charge power Pc, and the charging rate S in one day when the independent operation system 100 is operating independently from the power grid 200. [Figure 10] FIG. 22 illustrates an example of a computer 2200 in which aspects of the autonomous driving system 100 may be embodied, in whole or in part. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] The present invention will be described below through embodiments of the invention, but the following embodiments do not limit the scope of the invention according to the claims. Furthermore, not all of the combinations of features described in the embodiments are necessarily essential to the solution of the invention.

[0017] Fig. 1 is a diagram showing an example of an independent operation system 100 according to an embodiment of the present invention. The independent operation system 100 includes a power storage device 20, a fuel cell or the like 30, and a load facility 40. The independent operation system 100 may include a renewable energy power generation facility 10. In this example, the independent operation system 100 includes the renewable energy power generation facility 10. In Fig. 1, the scope of the independent operation system 100 is indicated by a dashed line.

[0018] The fuel cells etc. 30 refer to at least one of a fuel cell and an internal combustion power generation facility. The internal combustion power generation facility refers to a power generation facility using an internal combustion engine. The internal combustion engine is, for example, a diesel engine, a gasoline engine, etc. Electricity from the power system 200 is supplied to the power storage device 20, the fuel cells etc. 30, and the load facility 40 via the power transmission line 60 and the wiring 62. Electricity from the power system 200 may be supplied to the renewable energy power generation facility 10 via the power transmission line 60 and the wiring 62.

[0019] The renewable energy power generation facility 10 is, for example, at least one of a solar cell and a wind power generation device. The power storage device 20 may include a storage battery 22 and a PCS (power conditioner) 24. The PCS 24 converts the discharge power of the storage battery 22 from DC to AC, and converts the charge power from AC to DC.

[0020] The power storage device 20 may include a storage battery 22, a PCS (power conditioner) 24, and a memory unit 26. The PCS 24 converts the discharge power of the storage battery 22 from DC to AC, and converts the charge power from AC to DC. The memory unit 26 stores the relationship between the upper limit power Pmax (described later) or the demand power Pdm (described later) and a target charging rate Sd (described later). The memory unit 26 will be described later.

[0021] The load equipment 40 is equipment that operates by receiving power supply. The load equipment 40 may be a so-called consumer load.

[0022] The interrupting means 50 interrupts the electrical connection between the power transmission line 60 and the wiring 62 when lightning strikes the power system 200. This interrupts the supply of power from the power system 200 to the renewable energy power generation facility 10, the power storage device 20, the fuel cell etc. 30, and the load facility 40. The independent operation system 100 is capable of independent operation independent of the power system 200. In other words, when the supply of power from the power system 200 is interrupted by the interrupting means 50, the independent operation system 100 independently operates the power storage device 20, the fuel cell etc. 30, and the load facility 40 connected to the wiring 62.

[0023] The control means 90 acquires the output power from the fuel cell etc. 30, the discharge power of the power storage device 20 or the charging power to the power storage device 20, and the generated power of the renewable energy power generation facility 10 through the communication line 64. The control means 90 controls the output power of the fuel cell etc. 30 based on the output power, the discharge power or the charging power, and the generated power acquired through the communication line 64.

[0024] FIG. 2 is a diagram showing an example of frequency f control in the independent operation system 100. The charging rate of the power storage device 20 is defined as charging rate S. The charging rate S is the ratio of the remaining capacity to the total storage capacity of the power storage device 20. In this example, the charging rate S is the ratio of the remaining storage amount to the total storage capacity of the storage battery 22. The charging rate S is also referred to as SOC (State of Charge). FIG. 2 includes an example of frequency f control when the charging rate S of the power storage device 20 exceeds an upper limit and falls below a lower limit. The upper and lower limits of the charging rate S are defined as an upper limit UL and a lower limit DL, respectively.

[0025] In this example, the charging rate S is equal to the upper limit UL from time ta to time tb, and is equal to the lower limit DL from time tc to time td. In Fig. 2, the charging rate S from time ta to time tb and the charging rate S from time tc to time td are shown by thick lines.

[0026] The frequency f0 shown in Fig. 2 is a predetermined frequency of the isolated operation system 100. The frequency f0 may be 50 Hz. The frequency of the isolated operation system 100 at times ta and tb is set to frequency fu. The frequency of the isolated operation system 100 at times tc and td is set to frequency fd. The frequencies fu and fd are, for example, 50.2 Hz and 49.8 Hz.

[0027] In this example, the charging rate S is equal to the upper limit UL from time ta to time tb. Therefore, it is difficult for the independent operation system 100 to control the frequency f from time ta to time tb. In this example, the charging rate S is equal to the lower limit DL from time tc to time td. Therefore, it is difficult for the independent operation system 100 to control the frequency f from time tc to time td. In order for the independent operation system 100 to maintain an independent operation independent of the power system 200, it is preferable that the charging rate S is maintained between the upper limit UL and the lower limit DL. In FIG. 2, the frequency f from time ta to time tb and the frequency f from time tc to time td are shown by thick lines.

[0028] 3A is a block diagram showing an example of output control of the fuel cell etc. 30 when the independent operation system 100 is operating independently from the power grid 200. The demand power of the load equipment 40 is assumed to be demand power Pdm. The output power of the fuel cell etc. 30 is assumed to be output power Pf. The generated power of the renewable energy power generation equipment 10 is assumed to be generated power Pg. The discharged power of the power storage device 20 is assumed to be discharged power Pd, and the charging power to the power storage device 20 is assumed to be charged power Pc.

[0029] The independent operation system 100 may include an adder 31, a PI control unit 32, an adder 33, an upper limit limiter 36, and a change rate limiter 34. The discharge power Pd of the power storage device 20 or the charge power Pc to the power storage device 20 is defined as the storage battery power P. The demand power Pdm, or the sum of the output power Pf, the generated power Pg, and the storage battery power P is defined as power P1.

[0030] The adder 31 subtracts the current output power Pf of the fuel cell etc. 30 from the power P1. The adder 31 outputs the power P2. The power P2 is the power obtained by subtracting the output power Pf from the power P1. The PI control unit 32 outputs the power P3 obtained by PI controlling the power P2. The adder 33 adds the power P3 and the corrected stored power Pa. The corrected stored power Pa is the power obtained by correcting the power stored in the power storage device 20. The corrected stored power Pa will be described later. The adder 33 outputs the power P4. The power P4 is the power obtained by adding the power P3 and the corrected stored power Pa.

[0031] The upper limit limiting unit 36 ​​limits the upper limit of the power P4 based on the limited power Pr. The limited power Pr is the power obtained by subtracting the power generated by the renewable energy power generation facility Pg from the upper limit power Pmax or the demand power Pdm, as described below. The upper limit limiting unit 36 ​​limits the upper limit of the output power Pf of the fuel cell etc. 30 by controlling the upper limit of the power P4. The upper limit limiting unit 36 ​​may output power P5 obtained by limiting the upper limit of the power P4.

[0032] The change rate limiting unit 34 limits the time rate of change of the electric power P5. An upper limit of the time rate of change of the output power Pf of the fuel cell etc. 30 may be determined in advance. The upper limit is, for example, a change rate of 1% of 100 kW per minute (1% / min). Therefore, the change rate limiting unit 34 limits the time rate of change of the electric power P5 so that the time rate of change of the output power Pf does not exceed the upper limit. The change rate limiting unit 34 outputs electric power p5 with the time rate of change of the electric power P5 limited. The fuel cell etc. 30 is controlled by the electric power P5.

[0033] 3B is a block diagram showing an example of control for deriving the corrected stored power Pa from the charging rate S. The independent operation system 100 may include an adder 38 and a controller 39.

[0034] A predetermined target charging rate of the power storage device 20, which is between an upper limit UL and a lower limit DL of the charging rate S, is defined as a target charging rate Sd. A current charging rate of the power storage device 20 is defined as a charging rate Sp. A corrected stored power obtained by correcting the power stored in the power storage device 20 is defined as a corrected stored power Pa (see FIG. 3A). The corrected stored power Pa may be calculated based on the charging rate Sp and the target charging rate Sd. In this example, the adder 38 subtracts the charging rate Sp from the target charging rate Sd. In this example, the control unit 39 derives the corrected stored power Pa by controlling the result of subtracting the charging rate Sp from the target charging rate Sd. The control unit 39 may derive the corrected stored power Pa by controlling the gain of the result of subtracting the charging rate Sp from the target charging rate Sd.

[0035] Fig. 4 is a conceptual diagram showing an example of the changes in the power demand Pdm of the load equipment 40, the power output Pf of the fuel cell or the like 30, and the power generation Pg of the renewable energy power generation equipment 10 over a day when the isolated operation system 100 is operating independently of the power grid 200. The output power Pf in Fig. 4 is controlled by the block diagram shown in Fig. 3A.

[0036] The power demand Pdm is the power required to operate the load equipment 40. The power demand Pdm may be the sum of all consumer loads in the isolated operation system 100. When the isolated operation system 100 is operating independently from the power grid 200, the generated power Pg and the output power Pf are supplied to the load equipment 40.

[0037] This is an example of a case where the power generation power Pg of the renewable energy power generation facility 10 is negligibly small compared to the power demand Pdm. In the case of bad weather, etc., the power generation power Pg of the renewable energy power generation facility 10 may become negligibly small compared to the power demand Pdm over a day. Even when the load facilities 40 are increased due to a change in the independent operation system 100, etc., the power generation power Pg of the renewable energy power generation facility 10 may become negligibly small compared to the power demand Pdm over a day. The power generation power Pg being negligibly small compared to the power demand Pdm may be a case where the power generation power Pg is less than 5% of the power demand Pdm, or may be less than 1%.

[0038] 4, the change over time in the demand power Pdm is indicated by a solid line, the output power Pf by a fine dashed line, and the generated power Pg by a dashed line. The demand power Pdm is the power required to operate the load equipment 40. The demand power Pdm may be the sum of all consumer loads in the isolated operation system 100. When the isolated operation system 100 is operating independently from the power grid 200, the generated power Pg and the output power Pf are supplied to the load equipment 40. In this example, the generated power Pg is negligibly small compared to the demand power Pdm, so the output power Pf is supplied to the load equipment 40.

[0039] Time tt1 is the time when the power demand Pdm starts to increase from the lower limit power Pmin. After time tt1, the output power Pf starts to increase to meet the power demand Pdm. The time rate of change of the output power Pf is likely to be smaller than the time rate of change of the power demand Pdm. For this reason, it is difficult for the output power Pf to follow the power demand Pdm. For this reason, the power to meet the power demand Pdm is insufficient. To make up for the power shortage, the discharge power Pd of the power storage device 20 is further supplied to the load equipment 40, as described below. In this example, the power storage device 20 operates the load equipment 40 with charge / discharge control that realizes the supply of "rated voltage and rated frequency" to the load equipment 40. As a result, the frequency and voltage of the wiring 62 in the isolated operation system 100 are maintained within an appropriate range.

[0040] Time tt2 is the time when the demand power Pdm becomes equal to the upper limit power Pmax based on the capacity of the load equipment 40. In this example, from time tt2 to time tt4, the demand power Pdm is equal to the upper limit power Pmax. Time tt3 is the time when the output power Pf becomes equal to the demand power Pdm (upper limit power Pmax). The amount of discharged power from time tt1 to time tt3 is defined as the amount of discharged power Pd1. The amount of discharged power Pd1 is indicated by the area of ​​region D1 in FIG. 4.

[0041] Time tt4 is the time when the demand power Pdm starts to decrease from the upper limit power Pmax. After time tt4, the output power Pf starts to decrease. The time rate of change of the output power Pf tends to be smaller than the time rate of change of the demand power Pdm. For this reason, it is difficult for the output power Pf to follow the demand power Pdm. For this reason, after time tt3, in order to prevent power exceeding the demand power Pdm from being supplied to the load equipment 40, the power exceeding the demand power Pdm is stored (charged) in the power storage device 20, as described below. This power is referred to as charging power Pc.

[0042] Time tt5 is the time when the demand power Pdm becomes equal to the lower limit power Pmin. In this example, from time tt5 to time tt1 in the next day, the demand power Pdm becomes equal to the lower limit power Pmin. Time tt6 is the time when the output power Pf becomes equal to the demand power Pdm (lower limit power Pmin). The amount of charging energy from time tt4 to time tt6 is defined as the amount of charging energy Pc1. The amount of charging energy Pc1 is indicated by the area of ​​region D2 in FIG. 4.

[0043] The independent operation system 100 sets the target charging rate Sd of the power storage device 20 for a predetermined period of one day based on the relationship between the power demand Pdm in the load equipment 40 and the charging rate S of the power storage device 20. Therefore, even if the generated power Pg is negligibly small compared to the power demand Pdm over a one-day period, the charging rate S is likely to be set appropriately.

[0044] The independent operation system 100 may set the target charging rate Sd of the power storage device 20 based on the relationship between the limited power Pr (see FIG. 3A) obtained by subtracting the power generation power Pg of the renewable energy power generation facility from the power demand Pdm, and the charging rate S of the power storage device 20, during a predetermined period of one day. When the power generation power Pg exceeds a predetermined magnitude compared to the power demand Pdm, the independent operation system 100 may control the charging rate S of the power storage device 20 based on the power obtained by subtracting the power generation power Pg from the upper limit power Pmax or the power demand Pdm, and the output power Pf. This makes it easier to control the charging rate S more appropriately. The predetermined magnitude of the power generation power Pg compared to the power demand Pdm is, for example, when the power generation power Pg is 5% or more of the power demand Pdm.

[0045] 5 is a diagram showing an example of the relationship between the power demand Pdm and the target charging rate Sd of the power storage device 20. Between the upper limit UL and the lower limit DL, the maximum value of the target charging rate Sd is set to a maximum target charging rate Sdmax, and the minimum value is set to a minimum target charging rate Sdmin.

[0046] The target charging rate Sd may change according to the change in the demand power Pdm. The standard form Est of the independent operation system 100 is a case where the target charging rate Sd changes at a predetermined rate of change with respect to the change in the demand power Pdm. In this example, in the standard form Est, the target charging rate Sd changes in proportion to the change in the demand power Pdm. The standard form Est is a case where the renewable energy power generation equipment 10 generates a predetermined generated power Pg. The standard form Est may be a case where the renewable energy power generation equipment 10 generates an expected generated power Pg. In FIG. 5, the relationship between the demand power Pdm and the target charging rate Sd in the standard form Est is shown by a dashed line. In the standard form Est of this example, the target charging rate Sd changes linearly with the change in the demand power Pdm. The standard form Est may be a case where the generated power Pg is not negligibly small compared to the demand power Pdm.

[0047] When the target charging rate Sd is set higher than the standard mode Est from the lower limit power Pmin to the upper limit power Pmax, the charging rate is set to a high charging rate mode EH of the isolated operation system 100. When the target charging rate Sd is set lower than the standard mode Est from the lower limit power Pmin to the upper limit power Pmax, the charging rate is set to a low charging rate mode EL of the isolated operation system 100.

[0048] The storage unit 26 (see FIG. 1) may store the relationship between the demand power Pdm and the target charging rate Sd. The storage unit 26 may store the relationship between the demand power Pdm and the target charging rate Sd in each of the standard mode Est, the high charging rate mode EH, and the low charging rate mode EL. The storage unit 26 may store the relationship between the upper limit power Pmax and the target charging rate Sd, and may store the relationship between the lower limit power Pmin and the target charging rate Sd.

[0049] Fig. 6 is a diagram showing an example of time changes in the demand power Pdm of the load equipment 40, the output power Pf of the fuel cell or the like 30, the generated power Pg of the renewable energy power generation equipment 10, the discharge power Pd of the power storage device 20 or the charging power Pc to the power storage device 20, and the charging rate S of the power storage device 20 over a predetermined period of one day when the isolated operation system 100 is operating independently from the power grid 200. In the example shown in Fig. 6, the predetermined period is a daytime period. The output power Pf in Fig. 6 is controlled by the block diagram shown in Fig. 3A.

[0050] In FIG. 6, the time change of the demand power Pdm is shown by a solid line, the output power Pf is shown by a fine dashed line, the generated power Pg is shown by a dashed line, and the time change of the discharge power Pd or the charge power Pc is shown by a coarse dashed line. In FIG. 6, the time change of the charging rate S is shown by a two-dot dashed line. In FIG. 6, each time in a day is shown every four hours from 0:00. In this example, as in the example shown in FIG. 4, the generated power Pg is negligibly small compared to the demand power Pdm. When the generated power Pg is zero, the discharge power Pd is the value obtained by subtracting the output power Pf from the demand power Pdm, and the charge power Pc is the value obtained by subtracting the demand power Pdm from the output power Pf.

[0051] The time at which a predetermined period of a day begins is defined as time t0. Time t0 may be a time before the power demand Pdm starts to increase. In this example, the output power Pf of the fuel cell 30 starts to increase from time t0.

[0052] The time rate of change of the output power Pf is likely to be smaller than the time rate of change of the power demand Pdm. Therefore, at a predetermined timing after time t1, the power demand Pdm is likely to be larger than the output power Pf. This predetermined timing is assumed to be time t1'.

[0053] Time t2 is the time when the power demand Pdm becomes the upper limit power Pmax based on the capacity of the load equipment 40. The upper limit power Pmax may be the rated load of the grid in which the isolated operation system 100 operates independently. Time t3 is the time when the output power Pf becomes equal to the upper limit power Pmax. Time t4 is the time when the power demand Pdm starts to decrease.

[0054] The charging rate S of the power storage device 20 at time t0 is defined as the charging rate S0'. In this example, the output power Pf starts to increase from time t0. As a result, the charging rate S starts to increase from the charging rate S0' at time t0. The charging rate S increases until time t1' when the magnitude relationship between the power demand Pdm and the output power Pf is reversed, and then starts to decrease from time t1'.

[0055] The charging rate S at time t1' (maximum value of the charging rate S) is set as the charging rate S0. In this example, the independent operation system 100 sets the target charging rate Sd at time t0 higher than the target charging rate Sd a predetermined time before time t0. In this example, the power storage device 20 continues to supply discharge power Pd to the load equipment 40 from time t1' to time t3. Therefore, the charging rate S continues to decrease from the charging rate S0 from time t1' to time t3. In this example, the independent operation system 100 sets the charging rate Sd at time t0 higher than the target charging rate Sd before time t0, so that the charging rate S is less likely to become below the lower limit DL.

[0056] Note that this example is an example of setting the charging rate S when the generated power Pg of the renewable energy power generation equipment 10 is negligibly small compared to the demand power Pdm (for example, when the generated power Pg is less than 5% of the demand power Pdm). However, even when the generated power Pg is a predetermined magnitude compared to the demand power Pdm (for example, when the generated power Pg is 5% or more of the demand power Pdm), by setting the target charging rate Sd at time t0 higher than the target charging rate Sd a predetermined time before time t0, the charging rate S is less likely to become below the lower limit DL.

[0057] After time t0, the independent operation system 100 may set the charging rate S of the power storage device 20 to the standard form Est (see FIG. 5). The independent operation system 100 may set the charging rate S to be higher than the charging rate S set by the standard form Est by using the high charging rate form EH. The independent operation system 100 may set the charging rate S to be lower than the charging rate S set by the standard form Est by using the low charging rate form EL.

[0058] The independent operation system 100 may control the charging rate S of the power storage device 20 based on the relationship between the upper limit power Pmax or the demand power Pdm and the target charging rate Sd stored in the memory unit 26 (see FIG. 1). The independent operation system 100 may control the charging rate S based on the relationship between the upper limit power Pmax or the demand power Pdm and the target charging rate Sd in the case of the high charging rate mode EH stored in the memory unit 26.

[0059] FIG. 7 is a diagram showing a first comparative example of the changes in the power demand Pdm, the output power Pf, the generated power Pg, the discharged power Pd or the charged power Pc, and the charging rate S over one day when the isolated operation system 100 is operating independently from the power grid 200. In the first comparative example, the output power Pf of the fuel cell etc. 30 starts to increase from time t1. Therefore, the charging rate S of the power storage device 20 does not start to increase from time t0. The charging rate S is maintained at a charging rate S0' that is lower than the charging rate S0 until time t1. Therefore, in the first comparative example, after time t1, the charging rate S starts to decrease from the charging rate S0'. Therefore, the charging rate S is likely to become less than the lower limit DL.

[0060] Fig. 8 is a diagram showing an example of time changes in the demand power Pdm of the load equipment 40, the output power Pf of the fuel cell or the like 30, the discharge power Pd of the power storage device 20 or the charging power Pc to the power storage device 20, and the charging rate S of the power storage device 20 over a predetermined period of one day when the isolated operation system 100 is operating independently from the power grid 200. The output power Pf in Fig. 8 is controlled by the block diagram shown in Fig. 3A. Note that the generated power Pg of the renewable energy power generation facility 10 is omitted in Fig. 8.

[0061] In this example, the time when a predetermined period in one day ends is set to time t5. Time t5 may be the time when the power demand Pdm starts to decrease. In this example, the output power Pf of the fuel cell 30 starts to decrease from time t5.

[0062] The time rate of change of the output power Pf is likely to be smaller than the time rate of change of the power demand Pdm. Therefore, at a predetermined timing after time t5, the power demand Pdm is likely to be smaller than the output power Pf. The predetermined timing is time t6'. Time t7 is the time when the output power Pf becomes equal to the power demand Pdm (lower limit power Pmin).

[0063] The charging rate S of the power storage device 20 at time t5 is defined as charging rate S1'. In this example, the output power Pf starts to decrease from time t5. As a result, the charging rate S starts to decrease from the charging rate S1' at time t5. The charging rate S decreases until time t6' when the magnitude relationship between the power demand Pdm and the output power Pf is reversed, and then starts to increase from time t6'.

[0064] The charging rate S at time t6' (the minimum value of the charging rate S) is set as the charging rate S1. In this example, the independent operation system 100 sets the target charging rate Sd at time t5 lower than the target charging rate Sd a predetermined time before time t5. In this example, power exceeding the demand power Pdm continues to be supplied to the load equipment 40 from time t6' to time t8. Therefore, the charging rate S continues to increase from the charging rate S1 from time t6' to time t8. In this example, the independent operation system 100 sets the target charging rate Sd at time 5 lower than the target charging rate Sd a predetermined time before time t5, so that the charging rate S is less likely to exceed the upper limit UL.

[0065] The independent operation system 100 may set the target charging rate Sd of the power storage device 20 in the standard form Est (see FIG. 5) before time t5. The independent operation system 100 may set the target charging rate Sd higher than the target charging rate Sd set in the standard form Est by using the high charging rate form EH. The independent operation system 100 may set the target charging rate Sd lower than the target charging rate Sd set in the standard form Est by using the low charging rate form EL. The independent operation system 100 may set the target charging rate Sd to a preset value after time t5. This makes it possible to approach a lower charging rate for suppressing deterioration of the storage battery 22 (see FIG. 1) except for a predetermined period of a day, for example, a nighttime period.

[0066] The independent operation system 100 may control the charging rate S of the power storage device 20 based on the relationship between the upper limit power Pmax or the demand power Pdm and the target charging rate Sd stored in the memory unit 26 (see FIG. 1). The independent operation system 100 may control the charging rate S based on the relationship between the upper limit power Pmax or the demand power Pdm and the target charging rate Sd in the case of the low charging rate mode EL stored in the memory unit 26.

[0067] In the case of the power storage device 20 using a Li (lithium) ion battery, the charging rate S is preferably set lower than the median between the upper limit UL and the lower limit UL during the period from time t6' to time t0 (i.e., the nighttime period). By setting the charging rate lower than the median, the Li (lithium) ion battery is less likely to deteriorate.

[0068] FIG. 9 is a diagram showing a second comparative example of the changes in the power demand Pdm, the output power Pf, the discharge power Pd or the charge power Pc, and the charging rate S over one day when the independent operation system 100 is operating independently from the power grid 200. In the second comparative example, the output power Pf of the fuel cell etc. 30 starts to decrease from time t6. Therefore, the charging rate S of the power storage device 20 does not start to decrease from time t5. The charging rate S is maintained at the charging rate S1', which is higher than the charging rate S1, until time t6. Therefore, in the second comparative example, the charging rate S starts to increase from the charging rate S1' after time t6. Therefore, the charging rate S is likely to exceed the upper limit UL.

[0069] The independent operation system 100 may control the predetermined charging rate of the power storage device 20 based on the type of the power storage device 20. The type of the power storage device 20 may be the type of material of the electrodes of the storage battery 22 (see FIG. 1). When the storage battery 22 is a so-called lead storage battery, it is preferable that the charging rate S is maintained at 90% or more. A lead storage battery is a storage battery in which lead is used for the electrodes of the storage battery 22. When the storage battery 22 is a so-called Li (lithium) ion battery, it is preferable that the charging rate S is maintained at 30% or more and 80% or less. A Li (lithium) ion battery is a storage battery in which Li (lithium) is used for the electrodes of the storage battery 22. The independent operation system 100 may control the charging rate when a lead storage battery is used for the power storage device 20 to be higher than the charging rate when a Li (lithium) ion battery is used.

[0070] The independent operation system 100 may control the target charging rate Sd of the power storage device 20 based on the type of the power storage device 20. The independent operation system 100 may control the target charging rate Sd of the power storage device 20 in a high charging rate mode EH (see FIG. 5) or a low charging rate mode EL (see FIG. 5) based on the type of the power storage device 20.

[0071] When a lead-acid battery is used in the power storage device 20, the independent operation system 100 may control the target charging rate Sd of the power storage device 20 in the high charging rate mode EH. When a Li (lithium) ion battery is used in the power storage device 20, the independent operation system 100 may control the target charging rate Sd of the power storage device 20 in the low charging rate mode EL. When a Li (lithium) ion battery is used in the power storage device 20, if the charging rate S is continuously maintained at more than 80%, the Li (lithium) ion battery is more likely to deteriorate than if the charging rate S is continuously maintained at less than 80%. For this reason, when a Li (lithium) ion battery is used in the power storage device 20, it is preferable that the independent operation system 100 controls the target charging rate Sd of the power storage device 20 in the low charging rate mode EL.

[0072] 10 illustrates an example of a computer 2200 in which aspects of the autonomous driving system 100 may be embodied, in whole or in part. Programs installed on the computer 2200 may cause the computer 2200 to function as or perform operations associated with an apparatus or one or more sections of the apparatus according to embodiments of the present invention, and / or to perform a method or steps of a method according to embodiments of the present invention. Such programs may be executed by the CPU 2212 to cause the computer 2200 to perform specific operations associated with some or all of the blocks of the block diagrams described herein.

[0073] The computer 2200 according to this embodiment includes a CPU 2212, a RAM 2214, a graphic controller 2216, and a display device 2218, which are connected to each other by a host controller 2210. The computer 2200 also includes input / output units such as a communication interface 2222, a hard disk drive 2224, a DVD-ROM drive 2226, and an IC card drive, which are connected to the host controller 2210 via an input / output controller 2220. The computer also includes legacy input / output units such as a ROM 2230 and a keyboard 2242, which are connected to the input / output controller 2220 via an input / output chip 2240.

[0074] The CPU 2212 operates according to a program stored in the ROM 2230 and the RAM 2214, thereby controlling each unit. The graphic controller 2216 retrieves image data generated by the CPU 2212 into a frame buffer or the like provided in the RAM 2214 or into the graphic controller 2216 itself, and causes the image data to be displayed on the display device 2218.

[0075] The communication interface 2222 communicates with other electronic devices via a network. The hard disk drive 2224 stores programs and data used by the CPU 2212 in the computer 2200. The DVD-ROM drive 2226 reads programs or data from the DVD-ROM 2201 and provides the programs or data to the hard disk drive 2224 via the RAM 2214. The IC card drive reads programs and data from an IC card and / or writes programs and data to an IC card.

[0076] The ROM 2230 stores therein a boot program or the like executed by the computer 2200 upon activation, and / or a program that depends on the hardware of the computer 2200. The input / output chip 2240 may also connect various input / output units to the input / output controller 2220 via a parallel port, a serial port, a keyboard port, a mouse port, and the like.

[0077] The programs are provided by a computer-readable medium such as a DVD-ROM 2201 or an IC card. The programs are read from the computer-readable medium, installed in the hard disk drive 2224, the RAM 2214, or the ROM 2230, which are also examples of computer-readable media, and executed by the CPU 2212. Information processing described in these programs is read by the computer 2200, and brings about cooperation between the programs and the various types of hardware resources described above. An apparatus or method may be constructed by realizing information manipulation or processing according to the use of the computer 2200.

[0078] For example, when communication is performed between the computer 2200 and an external device, the CPU 2212 may execute a communication program loaded in the RAM 2214 and instruct the communication interface 2222 to perform communication processing based on the processing described in the communication program. Under the control of the CPU 2212, the communication interface 2222 reads transmission data stored in a transmission buffer processing area provided in the RAM 2214, the hard disk drive 2224, the DVD-ROM 2201, or a recording medium such as an IC card, and transmits the read transmission data to the network, or writes reception data received from the network to a reception buffer processing area or the like provided on the recording medium.

[0079] The CPU 2212 may cause all or a necessary portion of a file or database stored in an external recording medium such as the hard disk drive 2224, the DVD-ROM drive 2226 (DVD-ROM 2201), an IC card, etc. to be read into the RAM 2214, and perform various types of processing on the data on the RAM 2214. The CPU 2212 then writes back the processed data to the external recording medium.

[0080] Various types of information, such as various types of programs, data, tables, and databases, may be stored on the recording medium and may undergo information processing. The CPU 2212 may perform various types of processing on data read from the RAM 2214, including various types of operations, information processing, conditional decisions, conditional branches, unconditional branches, information search / replacement, etc., as described throughout this disclosure and specified by the instruction sequences of the programs, and writes the results back to the RAM 2214.

[0081] CPU2212 may search for information in a file, database, etc. in the recording medium. For example, when a plurality of entries each having an attribute value of a first attribute associated with an attribute value of a second attribute are stored in the recording medium, CPU2212 may search for an entry that matches a condition in which the attribute value of the first attribute is specified from among the plurality of entries, read the attribute value of the second attribute stored in the entry, and thereby obtain the attribute value of the second attribute associated with the first attribute that satisfies a predetermined condition.

[0082] The above-mentioned programs or software modules may be stored in a computer-readable medium on the computer 2200 or in the vicinity of the computer 2200. In addition, a recording medium such as a hard disk or a RAM provided in a server system connected to a dedicated communication network or the Internet can be used as a computer-readable medium, thereby providing the programs to the computer 2200 via the network.

[0083] Although the present invention has been described above using the embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments. It is clear to those skilled in the art that various modifications and improvements can be made to the above embodiments. It is clear from the description of the claims that such modifications and improvements can also be included in the technical scope of the present invention.

[0084] It should be noted that the order of execution of each process, such as operations, procedures, steps, and stages, in the devices, systems, programs, and methods shown in the claims, specifications, and drawings is not specifically stated as "before," "prior to," etc., and may be realized in any order unless the output of a previous process is used in a later process. Even if the operational flow in the claims, specifications, and drawings is explained using "first," "next," etc. for convenience, it does not mean that it is essential to perform the process in this order. [Item 1] An independent operation system capable of independent operation independent of a power grid, comprising a power storage device, at least one of a fuel cell and an internal combustion power generation facility, and a load facility, setting a target charging rate, which is a target value of the charging rate of the power storage device, based on a relationship between a power demand in the load equipment and the charging rate of the power storage device during a predetermined period of one day; Autonomous driving system. [Item 2] The target charging rate changes in response to a change in the power demand, 2. The independent operation system of claim 1, wherein the target charging rate is set based on a predetermined rate of change of the target charging rate in response to a change in the power demand. [Item 3] 3. The autonomous driving system according to item 2, wherein the target charging rate is set higher than the predetermined rate of change of the target charging rate. [Item 4] 3. The autonomous driving system according to item 2, wherein the target charging rate is set lower than the predetermined rate of change of the target charging rate. [Item 5] The power storage device has a storage unit that stores a relationship between the demanded power and the target charging rate, 5. The autonomous operation system according to any one of claims 2 to 4, wherein the charging rate of the power storage device is set based on the relationship between the demanded power and the target charging rate stored in the memory unit. [Item 6] An independent operation system according to any one of items 2 to 4, wherein the charging rate of the power storage device is set based on the type of the power storage device. [Item 7] An autonomous driving system according to any one of items 1 to 6, wherein the target charging rate at the start of the predetermined period in a day is set higher than the target charging rate at a predetermined time before the start of the predetermined period. [Item 8] An autonomous driving system according to any one of items 1 to 7, wherein the target charging rate at the end of the predetermined period in a day is set lower than the target charging rate at a predetermined time before the end of the predetermined period. [Item 9] It will also be equipped with renewable energy power generation facilities. setting the target charging rate based on a relationship between a limited power obtained by subtracting a generated power output from the renewable energy power generation facility from the demanded power during the predetermined period and the target charging rate; An autonomous driving system according to any one of items 1 to 8. [Item 10] A program for causing a computer to function as the autonomous driving system described in any one of items 1 to 9. [Explanation of symbols]

[0085] 10 Renewable energy power generation equipment, 20 Power storage device, 22 Storage battery, 24 PCS, 26 Memory unit, 30 Fuel cell or the like, 31 Addition unit, 32 PI control unit, 33 Addition unit, 34 Rate of change limit unit, 36 Upper limit limit unit, 38 Addition unit, 39 Control unit, 40 Load equipment, 50 Circuit breaker, 60 Transmission line, 62 Wiring, 64 Communication line, 90 Control unit, 100 Isolated operation system, 200 Power system , 2200···Computer, 2201···DVD-ROM, 2210···Host controller, 2212···CPU, 2214···RAM, 2216···Graphics controller, 2218···Display device, 2220···Input / output controller, 2222···Communication interface, 2224···Hard disk drive, 2226···DVD-ROM drive, 2230···ROM, 2240···Input / output chip, 2242···Keyboard

Claims

1. An independent operation system capable of independent operation independent of a power grid, comprising a power storage device, at least one of a fuel cell and an internal combustion power generation facility, a load facility, and a renewable energy power generation facility, A target charging rate is set as a target value of the charging rate of the power storage device based on a relationship between a power demand in the load equipment and a charging rate of the power storage device during a predetermined period of one day; and an upper limit limiting unit that limits an upper limit of the output power of at least one of the fuel cell and the internal combustion power generation facility to an upper limit power based on a capacity of the load facility or the demand power minus the generated power of the renewable energy power generation facility. Autonomous driving system.

2. An autonomous operation system as described in claim 1, further comprising a rate of change limiting unit that controls the time rate of change of the output power, the upper limit of which is limited by the upper limit limiting unit, based on a predetermined upper limit of the time rate of change of the output power.

3. An autonomous operation system as described in Claim 2, wherein the change rate limiting unit controls the time rate of change of the output power, the upper limit of which is limited by the upper limit limiting unit, so that it does not exceed a predetermined upper limit of the time rate of change of the output power.

4. An independent operation system capable of independent operation independent of a power grid, comprising a power storage device, at least one of a fuel cell and an internal combustion power generation device, and a load device, A target charging rate is set as a target value of the charging rate of the power storage device based on a relationship between a power demand in the load equipment and a charging rate of the power storage device during a predetermined period of one day; The target charging rate changes in response to a change in the power demand, The target charging rate is set to be higher than a predetermined rate of change of the target charging rate with respect to a change in the power demand. Autonomous driving system.

5. An independent operation system capable of independent operation independent of a power grid, comprising a power storage device, at least one of a fuel cell and an internal combustion power generation device, and a load device, A target charging rate is set as a target value of the charging rate of the power storage device based on a relationship between a power demand in the load equipment and a charging rate of the power storage device during a predetermined period of one day; The target charging rate changes in response to a change in the power demand, The target charging rate is set to be lower than a predetermined rate of change of the target charging rate with respect to a change in the power demand. Autonomous driving system.

6. The power storage device has a storage unit that stores a relationship between the demanded power and the target charging rate, The independent operation system according to claim 4 or 5, wherein the charging rate of the power storage device is set based on the relationship between the power demand and the target charging rate stored in the storage unit.

7. The independent operation system according to claim 4 or 5, wherein a charging rate of the power storage device is set based on a type of the power storage device.

8. An independent operation system capable of independent operation independent of a power grid, comprising a power storage device, at least one of a fuel cell and an internal combustion power generation device, and a load device, setting a target charging rate, which is a target value of the charging rate of the power storage device, based on a relationship between a power demand in the load equipment and a charging rate of the power storage device during a predetermined period of one day; setting the target charging rate at a start of the predetermined period in one day to be higher than the target charging rate at a predetermined time before the start of the predetermined period; Autonomous driving system.

9. An independent operation system capable of independent operation independent of a power grid, comprising a power storage device, at least one of a fuel cell and an internal combustion power generation device, and a load device, setting a target charging rate, which is a target value of the charging rate of the power storage device, based on a relationship between a power demand in the load equipment and a charging rate of the power storage device during a predetermined period of one day; setting the target charging rate at the end of the predetermined period in one day to be lower than the target charging rate at a predetermined time before the end of the predetermined period; Autonomous driving system.

10. An independent operation system capable of independent operation independent of a power grid, comprising a power storage device, at least one of a fuel cell and an internal combustion power generation facility, a load facility, and a renewable energy power generation facility, setting a target charging rate, which is a target value of the charging rate of the power storage device, based on a relationship between a power demand in the load equipment and a charging rate of the power storage device during a predetermined period of one day; setting the target charging rate based on a relationship between a limited power obtained by subtracting a generated power output from the renewable energy power generation facility from the demanded power during the predetermined period and the target charging rate; Autonomous driving system.

11. A program for causing a computer to function as the autonomous operation system according to any one of claims 1 to 10.

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